itsgoin/crates/core/src/node.rs

use std::net::SocketAddr;
use std::path::{Path, PathBuf};
use std::sync::atomic::{AtomicBool, AtomicU64, Ordering as AtomicOrdering};
use std::sync::Arc;

use tracing::{debug, info, warn};

use crate::activity::{ActivityCategory, ActivityEvent, ActivityLevel, ActivityLog};
use crate::blob::BlobStore;
use crate::content::compute_post_id;
use crate::crypto;
use crate::network::Network;
use crate::storage::StoragePool;
use crate::types::{
    Attachment, Circle,
    DeviceProfile, DeviceRole, NodeId, PeerRecord, PeerSlotKind, PeerWithAddress, Post, PostId,
    PostVisibility, PublicProfile, ReachMethod, RevocationMode, SessionReachMethod, SocialRelation,
    SocialRouteEntry, SocialStatus, VisibilityIntent, WormResult,
};

/// Built-in default anchor — always available as a bootstrap fallback.
const DEFAULT_ANCHOR: &str = "17af141956ae0b50dc1cb9248cadf5fca371ea2d8531ac9add3c03caffc61441@itsgoin.net:4433";

/// A distsoc node: ties together identity, storage, and networking
pub struct Node {
    pub data_dir: PathBuf,
    pub storage: Arc<StoragePool>,
    pub network: Arc<Network>,
    /// Network identity — used for QUIC connections / routing. Stays hidden
    /// from peers after the posting-key split ships end-to-end.
    pub node_id: NodeId,
    pub blob_store: Arc<BlobStore>,
    /// Active default posting identity's public NodeId. Used as `author` on
    /// content signed by this device.
    pub default_posting_id: NodeId,
    /// Active default posting identity's secret seed. Used to sign content
    /// (posts, manifests, reactions, comments, deletes) and to wrap/unwrap
    /// encryption keys.
    default_posting_secret: [u8; 32],
    bootstrap_anchors: tokio::sync::Mutex<Vec<(NodeId, iroh::EndpointAddr)>>,
    /// True if an anchor reported another instance of this identity is already active
    pub duplicate_detected: Arc<AtomicBool>,
    #[allow(dead_code)]
    profile: DeviceProfile,
    pub activity_log: Arc<std::sync::Mutex<ActivityLog>>,
    pub last_rebalance_ms: Arc<AtomicU64>,
    pub last_anchor_register_ms: Arc<AtomicU64>,
    /// CDN replication budget: bytes remaining we're willing to pull and cache this hour
    replication_budget_remaining: Arc<AtomicU64>,
    /// CDN delivery budget: bytes remaining we're willing to serve this hour
    delivery_budget_remaining: Arc<AtomicU64>,
    /// Last budget reset timestamp (ms)
    budget_last_reset_ms: Arc<AtomicU64>,
}

impl Node {
    /// Create or open a node in the given data directory (Desktop profile)
    pub async fn open(data_dir: impl AsRef<Path>) -> anyhow::Result<Self> {
        Self::open_with_bind(data_dir, None, DeviceProfile::Desktop).await
    }

    /// Create or open a mobile node in the given data directory
    pub async fn open_mobile(data_dir: impl AsRef<Path>) -> anyhow::Result<Self> {
        Self::open_with_bind(data_dir, None, DeviceProfile::Mobile).await
    }

    /// Create or open a node, optionally binding to a specific address
    pub async fn open_with_bind(
        data_dir: impl AsRef<Path>,
        bind_addr: Option<SocketAddr>,
        profile: DeviceProfile,
    ) -> anyhow::Result<Self> {
        let data_dir = data_dir.as_ref().to_path_buf();
        std::fs::create_dir_all(&data_dir)?;

        // Load or generate identity key (network secret — QUIC endpoint only,
        // never used as content author under the v0.6.1+ clean model).
        let key_path = data_dir.join("identity.key");
        let (mut secret_key, mut secret_seed) = if key_path.exists() {
            let key_bytes = std::fs::read(&key_path)?;
            let bytes: [u8; 32] = key_bytes
                .try_into()
                .map_err(|_| anyhow::anyhow!("invalid key file"))?;
            (iroh::SecretKey::from_bytes(&bytes), bytes)
        } else {
            let key = iroh::SecretKey::generate(&mut rand::rng());
            let seed = key.to_bytes();
            std::fs::write(&key_path, seed)?;
            info!("Generated new network identity key");
            (key, seed)
        };

        // Open storage
        let db_path = data_dir.join("itsgoin.db");
        let storage = Arc::new(StoragePool::open(&db_path)?);

        // Startup sweep: clear stale N2/N3 and mesh_peers from prior session
        {
            let s = storage.get().await;
            let n_cleared = s.clear_all_n2_n3().unwrap_or(0);
            let m_cleared = s.clear_all_mesh_peers().unwrap_or(0);
            if n_cleared > 0 || m_cleared > 0 {
                info!(n2_n3 = n_cleared, mesh_peers = m_cleared, "Startup sweep: cleared stale entries");
            }
        }

        // Ensure a default posting identity exists, INDEPENDENT of the network
        // key. On a fresh install we generate a new random ed25519 key as the
        // default persona. Peers who see our posts never learn our network key.
        {
            let s = storage.get().await;
            if s.count_posting_identities()? == 0 {
                let pk = iroh::SecretKey::generate(&mut rand::rng());
                let seed = pk.to_bytes();
                let nid: NodeId = *pk.public().as_bytes();
                let now = std::time::SystemTime::now()
                    .duration_since(std::time::UNIX_EPOCH)?
                    .as_millis() as u64;
                s.upsert_posting_identity(&crate::types::PostingIdentity {
                    node_id: nid,
                    secret_seed: seed,
                    display_name: String::new(),
                    created_at: now,
                })?;
                s.set_default_posting_id(&nid)?;
                info!(posting_id = %hex::encode(nid), "Generated initial posting identity (independent of network key)");
            }
        }

        // v0.6.0 → v0.6.1 migration: if the default posting key equals the
        // network key (which is what the Phase 4 migration did on upgrade from
        // v0.5), rotate the network key so they become independent. The old
        // key stays as the default posting identity — peers keep seeing the
        // same author; only the QUIC NodeId changes.
        {
            let s = storage.get().await;
            if let Some(default_id) = s.get_default_posting_id()? {
                if let Some(default_pi) = s.get_posting_identity(&default_id)? {
                    if default_pi.secret_seed == secret_seed {
                        let new_key = iroh::SecretKey::generate(&mut rand::rng());
                        let new_seed = new_key.to_bytes();
                        std::fs::write(&key_path, new_seed)?;
                        info!("v0.6.1 migration: rotated network key to decouple from default posting key");
                        secret_key = new_key;
                        secret_seed = new_seed;
                    }
                }
            }
        }

        // Open blob store
        let blob_store = Arc::new(BlobStore::open(&data_dir)?);

        // Activity log + timer atomics
        let activity_log = Arc::new(std::sync::Mutex::new(ActivityLog::new()));
        let last_rebalance_ms = Arc::new(AtomicU64::new(0));
        let last_anchor_register_ms = Arc::new(AtomicU64::new(0));

        // Start network (v2: single ALPN, connection manager)
        let network = Arc::new(
            Network::new(secret_key, Arc::clone(&storage), bind_addr, secret_seed, Arc::clone(&blob_store), profile, Arc::clone(&activity_log)).await?,
        );
        let node_id = network.node_id_bytes();

        // Resolve default posting identity (now guaranteed to exist).
        let (default_posting_id, default_posting_secret) = {
            let s = storage.get().await;
            let default_id = s.get_default_posting_id()?
                .ok_or_else(|| anyhow::anyhow!("default posting identity missing after initialization"))?;
            let pi = s.get_posting_identity(&default_id)?
                .ok_or_else(|| anyhow::anyhow!("default posting identity row missing"))?;
            (pi.node_id, pi.secret_seed)
        };

        // Auto-follow our default posting identity so our own posts show in
        // the feed. The network NodeId is not followed — it's never an author.
        {
            let s = storage.get().await;
            s.add_follow(&default_posting_id)?;
        }

        // Build the node (fast path — no network I/O beyond endpoint creation)
        let activity_log_ref = Arc::clone(&activity_log);
        let last_rebalance_ms = Arc::new(AtomicU64::new(0));
        let last_anchor_register_ms = Arc::new(AtomicU64::new(0));

        let role = network.device_role();
        let (replication_budget, delivery_budget) = (role.replication_limit(), role.delivery_limit());
        let replication_budget_remaining = Arc::new(AtomicU64::new(replication_budget));
        let delivery_budget_remaining = Arc::new(AtomicU64::new(delivery_budget));
        let budget_last_reset_ms = Arc::new(AtomicU64::new(
            std::time::SystemTime::now().duration_since(std::time::UNIX_EPOCH)
                .unwrap_or_default().as_millis() as u64
        ));
        blob_store.set_delivery_budget(delivery_budget);

        let mut node = Self {
            data_dir: data_dir.clone(),
            storage: Arc::clone(&storage),
            network: Arc::clone(&network),
            node_id,
            blob_store,
            default_posting_id,
            default_posting_secret,
            bootstrap_anchors: tokio::sync::Mutex::new(Vec::new()),
            duplicate_detected: Arc::new(AtomicBool::new(false)),
            profile,
            activity_log: activity_log_ref,
            last_rebalance_ms,
            last_anchor_register_ms,
            replication_budget_remaining,
            delivery_budget_remaining,
            budget_last_reset_ms,
        };

        Ok(node)
    }

    /// Bootstrap: connect to anchors, pull initial data, NAT probe, referrals.
    /// Can be called during open_with_bind (blocking startup) or deferred to background.
    pub async fn run_bootstrap(&self, data_dir: &Path) -> anyhow::Result<()> {
        let storage = &self.storage;
        let network = &self.network;
        let node_id = self.node_id;

        // Bootstrap: if peers table is empty, try bootstrap.json then default anchor
        {
            let s = storage.get().await;
            let has_peers = s.has_peers()?;
            drop(s);

            if !has_peers {
                let mut entries = Vec::new();
                let bootstrap_path = data_dir.join("bootstrap.json");
                if bootstrap_path.exists() {
                    info!("Loading bootstrap peers from {:?}", bootstrap_path);
                    if let Ok(data) = std::fs::read_to_string(&bootstrap_path) {
                        if let Ok(file_entries) = serde_json::from_str::<Vec<String>>(&data) {
                            entries.extend(file_entries);
                        }
                    }
                }
                let default = DEFAULT_ANCHOR.to_string();
                if !entries.contains(&default) {
                    entries.push(default);
                }

                for entry in entries {
                    match crate::parse_connect_string(&entry) {
                        Ok((nid, addr)) => {
                            if nid == node_id {
                                continue;
                            }
                            info!(peer = hex::encode(nid), "Bootstrap: connecting to peer");
                            let ip_addrs: Vec<_> = addr.ip_addrs().copied().collect();
                            {
                                let s = storage.get().await;
                                if ip_addrs.is_empty() {
                                    let _ = s.add_peer(&nid);
                                } else {
                                    let _ = s.upsert_peer(&nid, &ip_addrs, None);
                                }
                                // Mark as anchor — bootstrap peers are infrastructure, not social follows
                                let _ = s.set_peer_anchor(&nid, true);
                            }
                            // Connect persistently
                            match network.connect_to_peer(nid, addr).await {
                                Ok(()) => {
                                    info!(peer = hex::encode(nid), "Bootstrap: connected");
                                    // Pull posts from the bootstrap peer
                                    match network.pull_from_all().await {
                                        Ok(stats) => {
                                            info!(
                                                "Bootstrap pull: {} posts from {} peers",
                                                stats.posts_received, stats.peers_pulled
                                            );
                                        }
                                        Err(e) => warn!(error = %e, "Bootstrap pull failed"),
                                    }
                                    // Always store anchor in known_anchors (even before referrals)
                                    // so the periodic cycle can re-register and request referrals later
                                    {
                                        let s = storage.get().await;
                                        let anchor_addrs: Vec<std::net::SocketAddr> = s.get_peer_record(&nid)
                                            .ok().flatten()
                                            .map(|r| r.addresses).unwrap_or_default();
                                        if !anchor_addrs.is_empty() {
                                            let _ = s.upsert_known_anchor(&nid, &anchor_addrs);
                                        } else if !ip_addrs.is_empty() {
                                            let _ = s.upsert_known_anchor(&nid, &ip_addrs);
                                        }
                                    }

                                    // Request referrals from anchor (10s timeout)
                                    match tokio::time::timeout(std::time::Duration::from_secs(10), network.request_anchor_referrals(&nid)).await {
                                        Ok(Ok(referrals)) if !referrals.is_empty() => {
                                            info!(count = referrals.len(), "Bootstrap: got anchor referrals");
                                            // Spawn referral connections in background — don't block startup
                                            let net = Arc::clone(&network);
                                            let my_id = node_id;
                                            let anchor = nid;
                                            tokio::spawn(async move {
                                                for referral in referrals {
                                                    if referral.node_id == my_id {
                                                        continue;
                                                    }
                                                    if let Some(addr_str) = referral.addresses.first() {
                                                        let connect_str = format!(
                                                            "{}@{}",
                                                            hex::encode(referral.node_id),
                                                            addr_str,
                                                        );
                                                        if let Ok((rid, raddr)) = crate::parse_connect_string(&connect_str) {
                                                            let connect_fut = async {
                                                                match net.connect_to_peer(rid, raddr).await {
                                                                    Ok(()) => { info!(peer = hex::encode(rid), "Connected to referred peer"); Ok(()) },
                                                                    Err(e) => {
                                                                        debug!(error = %e, peer = hex::encode(rid), "One-sided connect failed, requesting introduction from anchor");
                                                                        match net.connect_via_introduction(rid, anchor).await {
                                                                            Ok(()) => { info!(peer = hex::encode(rid), "Connected to referred peer via hole punch"); Ok(()) },
                                                                            Err(e2) => Err(e2),
                                                                        }
                                                                    }
                                                                }
                                                            };
                                                            match tokio::time::timeout(std::time::Duration::from_secs(15), connect_fut).await {
                                                                Ok(Ok(())) => {},
                                                                Ok(Err(e)) => debug!(error = %e, peer = hex::encode(rid), "Bootstrap referral connect failed"),
                                                                Err(_) => debug!(peer = hex::encode(rid), "Bootstrap referral connect timed out"),
                                                            }
                                                        }
                                                    }
                                                }
                                                net.notify_growth().await;
                                            });
                                        }
                                        Ok(Ok(_)) => debug!("Bootstrap: no referrals from anchor (first to register)"),
                                        Ok(Err(e)) => debug!(error = %e, "Bootstrap: referral request failed"),
                                        Err(_) => debug!("Bootstrap: referral request timed out"),
                                    }
                                    break;
                                }
                                Err(e) => {
                                    warn!(error = %e, "Bootstrap peer failed, trying next");
                                }
                            }
                        }
                        Err(e) => {
                            warn!(entry = %entry, error = %e, "Invalid bootstrap entry");
                        }
                    }
                }
            }
        }

        // Load bootstrap anchors: anchors.json + built-in default
        let mut bootstrap_anchors = Vec::new();
        let mut anchor_ids = std::collections::HashSet::new();

        let anchors_path = data_dir.join("anchors.json");
        if anchors_path.exists() {
            if let Ok(data) = std::fs::read_to_string(&anchors_path) {
                if let Ok(entries) = serde_json::from_str::<Vec<String>>(&data) {
                    for entry in entries {
                        match crate::parse_connect_string(&entry) {
                            Ok((nid, addr)) => {
                                info!(peer = hex::encode(nid), "Loaded bootstrap anchor");
                                anchor_ids.insert(nid);
                                bootstrap_anchors.push((nid, addr));
                            }
                            Err(e) => {
                                warn!(entry = %entry, error = %e, "Invalid bootstrap anchor entry");
                            }
                        }
                    }
                }
            }
        }

        if let Ok((nid, addr)) = crate::parse_connect_string(DEFAULT_ANCHOR) {
            if nid != node_id && !anchor_ids.contains(&nid) {
                info!("Including built-in default anchor");
                bootstrap_anchors.push((nid, addr));
            }
        }

        // Collect bootstrap anchor node IDs so we can deprioritize them
        let bootstrap_anchor_ids: std::collections::HashSet<NodeId> =
            bootstrap_anchors.iter().map(|(nid, _)| *nid).collect();

        // Update known_anchors + peers with freshly DNS-resolved bootstrap addresses.
        // Without this, stale IPv6 addresses from previous sessions can block reconnection
        // on devices without IPv6 connectivity (see bugs-fixed.md #1).
        {
            let s = storage.get().await;
            for (nid, addr) in &bootstrap_anchors {
                let ip_addrs: Vec<std::net::SocketAddr> = addr.ip_addrs().copied().collect();
                if !ip_addrs.is_empty() {
                    let _ = s.upsert_known_anchor(nid, &ip_addrs);
                    let _ = s.upsert_peer(nid, &ip_addrs, None);
                }
            }
        }

        // Rebuild social routes from follows + audience
        {
            let s = storage.get().await;
            match s.rebuild_social_routes() {
                Ok(count) if count > 0 => info!(count, "Rebuilt social routes on startup"),
                _ => {}
            }
        }

        // Startup connection: try discovered anchors FIRST, bootstrap anchors LAST.
        // This keeps load off bootstrap anchors — they're only needed when nothing else works.
        // Order: known non-bootstrap anchors → mDNS (via iroh) → bootstrap anchors
        {
            let conn_count = network.connection_count().await;
            if conn_count < 5 {
                let known = {
                    let s = storage.get().await;
                    s.list_known_anchors().unwrap_or_default()
                };
                // Split into discovered anchors (priority) and bootstrap anchors (fallback)
                let (discovered, bootstrap_known): (Vec<_>, Vec<_>) = known.into_iter()
                    .partition(|(nid, _)| !bootstrap_anchor_ids.contains(nid));

                // Phase 1: Try discovered (non-bootstrap) anchors first
                let mut connected_anchor = None;
                for (anchor_nid, anchor_addrs) in &discovered {
                    if *anchor_nid == node_id || network.is_peer_connected_or_session(anchor_nid).await {
                        continue;
                    }
                    let endpoint_id = match iroh::EndpointId::from_bytes(anchor_nid) {
                        Ok(eid) => eid,
                        Err(_) => continue,
                    };
                    let mut addr = iroh::EndpointAddr::from(endpoint_id);
                    for sa in anchor_addrs {
                        addr = addr.with_ip_addr(*sa);
                    }
                    info!(peer = hex::encode(anchor_nid), "Trying discovered anchor");
                    match tokio::time::timeout(std::time::Duration::from_secs(10), network.connect_to_anchor(*anchor_nid, addr)).await {
                        Ok(Ok(())) => {
                            info!(peer = hex::encode(anchor_nid), "Connected to discovered anchor");
                            connected_anchor = Some(*anchor_nid);
                            break;
                        }
                        Ok(Err(e)) => debug!(error = %e, peer = hex::encode(anchor_nid), "Discovered anchor: connect failed"),
                        Err(_) => debug!(peer = hex::encode(anchor_nid), "Discovered anchor: connect timed out"),
                    }
                }

                // Phase 2: Fall back to bootstrap anchors only if no discovered anchor worked
                if connected_anchor.is_none() {
                    for (anchor_nid, anchor_addrs) in &bootstrap_known {
                        if *anchor_nid == node_id || network.is_peer_connected_or_session(anchor_nid).await {
                            continue;
                        }
                        let endpoint_id = match iroh::EndpointId::from_bytes(anchor_nid) {
                            Ok(eid) => eid,
                            Err(_) => continue,
                        };
                        let mut addr = iroh::EndpointAddr::from(endpoint_id);
                        for sa in anchor_addrs {
                            addr = addr.with_ip_addr(*sa);
                        }
                        info!(peer = hex::encode(anchor_nid), "Trying bootstrap anchor (fallback)");
                        match tokio::time::timeout(std::time::Duration::from_secs(10), network.connect_to_anchor(*anchor_nid, addr)).await {
                            Ok(Ok(())) => {
                                info!(peer = hex::encode(anchor_nid), "Connected to bootstrap anchor");
                                connected_anchor = Some(*anchor_nid);
                                break;
                            }
                            Ok(Err(e)) => debug!(error = %e, peer = hex::encode(anchor_nid), "Bootstrap anchor: connect failed"),
                            Err(_) => debug!(peer = hex::encode(anchor_nid), "Bootstrap anchor: connect timed out"),
                        }
                    }
                }

                // Phase 3: NAT probe + referrals from whichever anchor we connected to
                if let Some(anchor_nid) = connected_anchor {
                    match tokio::time::timeout(
                        std::time::Duration::from_secs(15),
                        network.request_nat_filter_probe(&anchor_nid),
                    ).await {
                        Ok(Ok(())) => info!("NAT filter probe completed during bootstrap"),
                        Ok(Err(e)) => warn!(error = %e, "NAT filter probe failed during bootstrap"),
                        Err(_) => warn!("NAT filter probe timed out during bootstrap"),
                    }
                    match tokio::time::timeout(std::time::Duration::from_secs(10), network.request_anchor_referrals(&anchor_nid)).await {
                        Ok(Ok(referrals)) if !referrals.is_empty() => {
                            info!(count = referrals.len(), "Got anchor referrals");
                            let net = Arc::clone(&network);
                            let my_id = node_id;
                            let anchor = anchor_nid;
                            tokio::spawn(async move {
                                for referral in referrals {
                                    if referral.node_id == my_id {
                                        continue;
                                    }
                                    if let Some(addr_str) = referral.addresses.first() {
                                        let connect_str = format!(
                                            "{}@{}",
                                            hex::encode(referral.node_id),
                                            addr_str,
                                        );
                                        if let Ok((rid, raddr)) = crate::parse_connect_string(&connect_str) {
                                            let connect_fut = async {
                                                match net.connect_to_peer(rid, raddr).await {
                                                    Ok(()) => { info!(peer = hex::encode(rid), "Connected to referred peer"); Ok(()) },
                                                    Err(_) => {
                                                        match net.connect_via_introduction(rid, anchor).await {
                                                            Ok(()) => { info!(peer = hex::encode(rid), "Connected via hole punch"); Ok(()) },
                                                            Err(e) => Err(e),
                                                        }
                                                    }
                                                }
                                            };
                                            match tokio::time::timeout(std::time::Duration::from_secs(15), connect_fut).await {
                                                Ok(Ok(())) => {},
                                                Ok(Err(e)) => debug!(error = %e, peer = hex::encode(rid), "Referral connect failed"),
                                                Err(_) => debug!(peer = hex::encode(rid), "Referral connect timed out"),
                                            }
                                        }
                                    }
                                }
                                net.notify_growth().await;
                            });
                        }
                        Ok(Ok(_)) => debug!("No referrals from anchor"),
                        Ok(Err(e)) => debug!(error = %e, "Referral request failed"),
                        Err(_) => debug!("Referral request timed out"),
                    }
                }
            }
        }

        // Store bootstrap anchors on the node
        *self.bootstrap_anchors.lock().await = bootstrap_anchors;

        Ok(())
    }

    /// Get recent activity events (for diagnostics UI).
    pub fn get_activity_log(&self, limit: usize) -> Vec<ActivityEvent> {
        self.activity_log.lock().unwrap().recent(limit)
    }

    /// Get timer state: (last_rebalance_ms, last_anchor_register_ms).
    pub fn timer_state(&self) -> (u64, u64) {
        (
            self.last_rebalance_ms.load(AtomicOrdering::Relaxed),
            self.last_anchor_register_ms.load(AtomicOrdering::Relaxed),
        )
    }

    /// Get the secret seed bytes (for crypto operations by consumers like Tauri)
    pub fn secret_seed_bytes(&self) -> [u8; 32] {
        self.default_posting_secret
    }

    // --- CDN Replication Budget ---

    /// Reset budgets if an hour has elapsed since last reset.
    fn maybe_reset_budgets(&self) {
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)
            .unwrap_or_default()
            .as_millis() as u64;
        let last = self.budget_last_reset_ms.load(AtomicOrdering::Relaxed);
        if now.saturating_sub(last) >= 3_600_000 {
            let role = self.network.device_role();
            self.replication_budget_remaining.store(role.replication_limit(), AtomicOrdering::Relaxed);
            self.delivery_budget_remaining.store(role.delivery_limit(), AtomicOrdering::Relaxed);
            self.budget_last_reset_ms.store(now, AtomicOrdering::Relaxed);
            debug!(role = %role, "CDN budgets reset for new hour");
        }
    }

    /// Try to consume replication budget. Returns true if within budget.
    pub fn consume_replication_budget(&self, bytes: u64) -> bool {
        self.maybe_reset_budgets();
        let prev = self.replication_budget_remaining.fetch_update(
            AtomicOrdering::Relaxed,
            AtomicOrdering::Relaxed,
            |current| {
                if current >= bytes { Some(current - bytes) } else { None }
            },
        );
        prev.is_ok()
    }

    /// Try to consume delivery budget. Returns true if within budget.
    pub fn consume_delivery_budget(&self, bytes: u64) -> bool {
        self.maybe_reset_budgets();
        let prev = self.delivery_budget_remaining.fetch_update(
            AtomicOrdering::Relaxed,
            AtomicOrdering::Relaxed,
            |current| {
                if current >= bytes { Some(current - bytes) } else { None }
            },
        );
        prev.is_ok()
    }

    /// Get remaining replication budget bytes.
    pub fn replication_budget_remaining(&self) -> u64 {
        self.maybe_reset_budgets();
        self.replication_budget_remaining.load(AtomicOrdering::Relaxed)
    }

    /// Get remaining delivery budget bytes.
    pub fn delivery_budget_remaining(&self) -> u64 {
        self.maybe_reset_budgets();
        self.delivery_budget_remaining.load(AtomicOrdering::Relaxed)
    }

    // ---- Posting identities (multi-persona) ----

    /// List all posting identities held by this device.
    pub async fn list_posting_identities(&self) -> anyhow::Result<Vec<crate::types::PostingIdentity>> {
        let s = self.storage.get().await;
        s.list_posting_identities()
    }

    /// Create a new posting identity with a fresh ed25519 key. Auto-follows
    /// the new identity so its own posts show in the merged feed.
    pub async fn create_posting_identity(
        &self,
        display_name: String,
    ) -> anyhow::Result<crate::types::PostingIdentity> {
        let key = iroh::SecretKey::generate(&mut rand::rng());
        let seed: [u8; 32] = key.to_bytes();
        let node_id: NodeId = *key.public().as_bytes();
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;
        let identity = crate::types::PostingIdentity {
            node_id,
            secret_seed: seed,
            display_name,
            created_at: now,
        };
        let s = self.storage.get().await;
        s.upsert_posting_identity(&identity)?;
        // Auto-follow this persona so its own posts reach its own feed.
        s.add_follow(&node_id)?;
        Ok(identity)
    }

    /// Delete a posting identity. Refuses to delete the currently default
    /// posting identity unless the caller has already switched the default.
    pub async fn delete_posting_identity(&self, node_id: &NodeId) -> anyhow::Result<()> {
        let s = self.storage.get().await;
        if let Some(default) = s.get_default_posting_id()? {
            if default == *node_id {
                anyhow::bail!("cannot delete the default posting identity; set a different default first");
            }
        }
        s.delete_posting_identity(node_id)?;
        // Best-effort: remove the auto-follow row for this persona.
        let _ = s.remove_follow(node_id);
        Ok(())
    }

    /// Switch the default posting identity. Takes effect on next restart for
    /// the Node's cached fields, but new posts created via create_post_as can
    /// already use the new identity immediately.
    pub async fn set_default_posting_identity(&self, node_id: &NodeId) -> anyhow::Result<()> {
        let s = self.storage.get().await;
        if s.get_posting_identity(node_id)?.is_none() {
            anyhow::bail!("unknown posting identity");
        }
        s.set_default_posting_id(node_id)?;
        Ok(())
    }

    // ---- Identity export/import ----

    pub fn secret_seed(&self) -> [u8; 32] {
        self.default_posting_secret
    }

    pub fn export_identity_hex(&self) -> anyhow::Result<String> {
        let key_path = self.data_dir.join("identity.key");
        let key_bytes = std::fs::read(&key_path)?;
        Ok(hex::encode(key_bytes))
    }

    pub fn import_identity(data_dir: &Path, hex_key: &str) -> anyhow::Result<()> {
        std::fs::create_dir_all(data_dir)?;
        let key_path = data_dir.join("identity.key");
        if key_path.exists() {
            anyhow::bail!("identity.key already exists in {:?} — refusing to overwrite", data_dir);
        }
        let bytes = hex::decode(hex_key)?;
        if bytes.len() != 32 {
            anyhow::bail!("key must be exactly 32 bytes (64 hex chars), got {} bytes", bytes.len());
        }
        std::fs::write(&key_path, &bytes)?;
        Ok(())
    }

    /// Get up to 10 currently-connected peer NodeIds (for recent_peers in profile).
    /// Prefers social peers, then wide.
    async fn current_recent_peers(&self) -> Vec<NodeId> {
        let conns = self.network.connection_info().await;
        let mut social: Vec<NodeId> = Vec::new();
        let mut wide: Vec<NodeId> = Vec::new();
        for (nid, kind, _) in conns {
            if nid == self.node_id {
                continue;
            }
            match kind {
                PeerSlotKind::Preferred | PeerSlotKind::Local => social.push(nid),
                PeerSlotKind::Wide => wide.push(nid),
            }
        }
        let mut result = social;
        result.extend(wide);
        result.truncate(10);
        result
    }

    // ---- Posts ----

    pub async fn create_post(&self, content: String) -> anyhow::Result<(PostId, Post)> {
        let (id, post, _vis) = self
            .create_post_with_visibility(content, VisibilityIntent::Public, vec![])
            .await?;
        Ok((id, post))
    }

    pub async fn create_post_with_visibility(
        &self,
        content: String,
        intent: VisibilityIntent,
        attachment_data: Vec<(Vec<u8>, String)>,
    ) -> anyhow::Result<(PostId, Post, PostVisibility)> {
        self.create_post_inner(
            &self.default_posting_id,
            &self.default_posting_secret,
            content,
            intent,
            attachment_data,
        ).await
    }

    /// Create a post authored by a specific posting identity held by this
    /// device. Looks up the posting secret and routes through the same post
    /// creation pipeline as the default.
    pub async fn create_post_as(
        &self,
        posting_id: &NodeId,
        content: String,
        intent: VisibilityIntent,
        attachment_data: Vec<(Vec<u8>, String)>,
    ) -> anyhow::Result<(PostId, Post, PostVisibility)> {
        let identity = {
            let s = self.storage.get().await;
            s.get_posting_identity(posting_id)?
                .ok_or_else(|| anyhow::anyhow!("unknown posting identity"))?
        };
        self.create_post_inner(
            &identity.node_id,
            &identity.secret_seed,
            content,
            intent,
            attachment_data,
        ).await
    }

    async fn create_post_inner(
        &self,
        posting_id: &NodeId,
        posting_secret: &[u8; 32],
        content: String,
        intent: VisibilityIntent,
        attachment_data: Vec<(Vec<u8>, String)>,
    ) -> anyhow::Result<(PostId, Post, PostVisibility)> {
        // Validate attachments
        if attachment_data.len() > 4 {
            anyhow::bail!("max 4 attachments per post");
        }
        for (data, _) in &attachment_data {
            if data.len() > 10 * 1024 * 1024 {
                anyhow::bail!("attachment exceeds 10MB limit");
            }
        }

        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        // Determine encryption parameters and generate CEK if needed.
        // The CEK is generated BEFORE both content and blob encryption so they share the same key.
        enum EncryptionMode {
            Public,
            Recipient { cek: [u8; 32], recipients: Vec<NodeId> },
            Group { cek: [u8; 32], group_id: [u8; 32], epoch: u64, group_seed: [u8; 32], group_pubkey: [u8; 32] },
        }

        let mode = match &intent {
            VisibilityIntent::Public => EncryptionMode::Public,
            VisibilityIntent::Circle(circle_name) => {
                // Try group encryption first
                let group_info = {
                    let storage = self.storage.get().await;
                    storage.get_group_key_by_circle(circle_name)?
                        .and_then(|gk| {
                            storage.get_group_seed(&gk.group_id, gk.epoch).ok().flatten()
                                .map(|seed| (gk.group_id, gk.epoch, seed, gk.group_public_key))
                        })
                };
                if let Some((group_id, epoch, group_seed, group_pubkey)) = group_info {
                    let mut cek = [0u8; 32];
                    rand::RngCore::fill_bytes(&mut rand::rng(), &mut cek);
                    EncryptionMode::Group { cek, group_id, epoch, group_seed, group_pubkey }
                } else {
                    let recipients = self.resolve_recipients(&intent).await?;
                    if recipients.is_empty() {
                        anyhow::bail!("no recipients resolved for this visibility");
                    }
                    let mut cek = [0u8; 32];
                    rand::RngCore::fill_bytes(&mut rand::rng(), &mut cek);
                    EncryptionMode::Recipient { cek, recipients }
                }
            }
            _ => {
                let recipients = self.resolve_recipients(&intent).await?;
                if recipients.is_empty() {
                    anyhow::bail!("no recipients resolved for this visibility");
                }
                let mut cek = [0u8; 32];
                rand::RngCore::fill_bytes(&mut rand::rng(), &mut cek);
                EncryptionMode::Recipient { cek, recipients }
            }
        };

        // Store blob files — for encrypted posts, encrypt each blob with the shared CEK.
        // CID is computed on the ciphertext so peers can verify what they store.
        let mut attachments = Vec::with_capacity(attachment_data.len());
        for (data, mime) in &attachment_data {
            let (store_data, size) = match &mode {
                EncryptionMode::Public => {
                    (data.clone(), data.len() as u64)
                }
                EncryptionMode::Recipient { cek, .. } | EncryptionMode::Group { cek, .. } => {
                    let encrypted = crypto::encrypt_bytes_with_cek(data, cek)?;
                    let sz = encrypted.len() as u64;
                    (encrypted, sz)
                }
            };
            let cid = crate::blob::compute_blob_id(&store_data);
            self.blob_store.store(&cid, &store_data)?;
            attachments.push(Attachment {
                cid,
                mime_type: mime.clone(),
                size_bytes: size,
            });
        }

        // Encrypt content and build visibility
        let (final_content, visibility) = match mode {
            EncryptionMode::Public => (content, PostVisibility::Public),
            EncryptionMode::Recipient { cek, recipients } => {
                let (encrypted, wrapped_keys) =
                    crypto::encrypt_post_with_cek(&content, &cek, posting_secret, posting_id, &recipients)?;
                (
                    encrypted,
                    PostVisibility::Encrypted {
                        recipients: wrapped_keys,
                    },
                )
            }
            EncryptionMode::Group { cek, group_id, epoch, group_seed, group_pubkey } => {
                let (encrypted, wrapped_cek) =
                    crypto::encrypt_post_for_group_with_cek(&content, &cek, &group_seed, &group_pubkey)?;
                (
                    encrypted,
                    PostVisibility::GroupEncrypted {
                        group_id,
                        epoch,
                        wrapped_cek,
                    },
                )
            }
        };

        let post = Post {
            author: *posting_id,
            content: final_content,
            attachments,
            timestamp_ms: now,
        };

        let post_id = compute_post_id(&post);

        {
            let storage = self.storage.get().await;
            storage.store_post_with_intent(&post_id, &post, &visibility, &intent)?;
            for att in &post.attachments {
                storage.record_blob(&att.cid, &post_id, posting_id, att.size_bytes, &att.mime_type, now)?;
                // Auto-pin own blobs so they're never evicted before foreign content
                let _ = storage.pin_blob(&att.cid);
            }

            // Initialize encrypted receipt + comment slots for non-public posts
            if !matches!(visibility, PostVisibility::Public) {
                let participant_count = match &visibility {
                    PostVisibility::Encrypted { recipients } => recipients.len(),
                    PostVisibility::GroupEncrypted { .. } => {
                        // For group posts, we don't know exact member count at creation time;
                        // use a reasonable default (the circle members count, resolved earlier)
                        match &intent {
                            VisibilityIntent::Circle(circle_name) => {
                                storage.get_circle_members(circle_name)
                                    .map(|m| m.len() + 1) // +1 for author
                                    .unwrap_or(2)
                            }
                            _ => 2,
                        }
                    }
                    PostVisibility::Public => unreachable!(),
                };

                let receipt_slots: Vec<Vec<u8>> = (0..participant_count)
                    .map(|_| crypto::random_slot_noise(64))
                    .collect();
                let comment_slot_count = (participant_count + 2) / 3; // ceil(participants / 3)
                let comment_slots: Vec<Vec<u8>> = (0..comment_slot_count)
                    .map(|_| crypto::random_slot_noise(256))
                    .collect();

                let blob_header = crate::types::BlobHeader {
                    post_id,
                    author: *posting_id,
                    reactions: vec![],
                    comments: vec![],
                    policy: Default::default(),
                    updated_at: now,
                    thread_splits: vec![],
                    receipt_slots,
                    comment_slots,
                    prior_author: None,
                };
                let header_json = serde_json::to_string(&blob_header)?;
                storage.store_blob_header(&post_id, posting_id, &header_json, now)?;
            }
        }

        // Build and store CDN manifests for blobs
        if !post.attachments.is_empty() {
            let storage = self.storage.get().await;
            let (previous, _following) = storage.get_author_post_neighborhood(posting_id, now, 10)?;
            drop(storage);

            let manifest = crate::types::AuthorManifest {
                post_id,
                author: *posting_id,
                author_addresses: self.network.our_addresses(),
                created_at: now,
                updated_at: now,
                previous_posts: previous,
                following_posts: vec![],
                signature: vec![],
            };
            let sig = crypto::sign_manifest(posting_secret, &manifest);
            let mut manifest = manifest;
            manifest.signature = sig;

            let manifest_json = serde_json::to_string(&manifest)?;
            {
                let storage = self.storage.get().await;
                for att in &post.attachments {
                    storage.store_cdn_manifest(&att.cid, &manifest_json, posting_id, now)?;
                }
            }

            // Update previous posts' manifests to include this new post as a following_post
            self.update_neighbor_manifests_as(posting_id, posting_secret, &post_id, now).await;

            // Push updated manifests to downstream peers
            let manifests_to_push = {
                let storage = self.storage.get().await;
                storage.get_manifests_for_author_blobs(posting_id).unwrap_or_default()
            };
            let our_addrs = self.network.our_addresses();
            for (push_cid, push_json) in &manifests_to_push {
                if let Ok(author_manifest) = serde_json::from_str::<crate::types::AuthorManifest>(push_json) {
                    let cdn_manifest = crate::types::CdnManifest {
                        author_manifest: author_manifest,
                        host: self.node_id,
                        host_addresses: our_addrs.clone(),
                        source: self.node_id,
                        source_addresses: our_addrs.clone(),
                        downstream_count: 0,
                    };
                    self.network.push_manifest_to_downstream(push_cid, &cdn_manifest).await;
                }
            }
        }

        // v0.6.2: posts propagate ONLY via the CDN (pull + header-diff
        // neighbor propagation). Persona-signed direct pushes (PostPush,
        // PostNotification) are gone — they exposed sender→recipient traffic.
        info!(post_id = hex::encode(post_id), "Created new post");
        Ok((post_id, post, visibility))
    }

    /// Update the manifests of recent prior posts to include a newly created post
    /// in their following_posts list. Re-signs each updated manifest.
    async fn update_neighbor_manifests_as(
        &self,
        posting_id: &NodeId,
        posting_secret: &[u8; 32],
        new_post_id: &PostId,
        new_timestamp_ms: u64,
    ) {
        let storage = self.storage.get().await;
        let manifests = match storage.get_manifests_for_author_blobs(posting_id) {
            Ok(m) => m,
            Err(e) => {
                warn!("Failed to get manifests for neighbor update: {}", e);
                return;
            }
        };
        drop(storage);

        let new_entry = crate::types::ManifestEntry {
            post_id: *new_post_id,
            timestamp_ms: new_timestamp_ms,
            has_attachments: true,
        };

        for (cid, json) in manifests {
            let mut manifest: crate::types::AuthorManifest = match serde_json::from_str(&json) {
                Ok(m) => m,
                Err(_) => continue,
            };
            // Only update if this manifest's post was created before the new post
            if manifest.created_at >= new_timestamp_ms {
                continue;
            }
            // Don't add duplicate
            if manifest.following_posts.iter().any(|e| e.post_id == *new_post_id) {
                continue;
            }
            // Keep max 10 following_posts
            if manifest.following_posts.len() >= 10 {
                continue;
            }
            manifest.following_posts.push(new_entry.clone());
            manifest.updated_at = new_timestamp_ms;
            manifest.signature = crypto::sign_manifest(posting_secret, &manifest);

            let updated_json = match serde_json::to_string(&manifest) {
                Ok(j) => j,
                Err(_) => continue,
            };
            let storage = self.storage.get().await;
            let _ = storage.store_cdn_manifest(&cid, &updated_json, posting_id, new_timestamp_ms);
            drop(storage);
        }
    }

    async fn resolve_recipients(&self, intent: &VisibilityIntent) -> anyhow::Result<Vec<NodeId>> {
        let storage = self.storage.get().await;
        match intent {
            VisibilityIntent::Public => Ok(vec![]),
            VisibilityIntent::Friends => storage.list_public_follows(),
            VisibilityIntent::Circle(name) => storage.get_circle_members(name),
            VisibilityIntent::Direct(ids) => Ok(ids.clone()),
            // Control and Profile posts are always Public on the wire; they
            // never go through encryption recipient resolution.
            VisibilityIntent::Control | VisibilityIntent::Profile => Ok(vec![]),
        }
    }

    pub async fn get_feed(
        &self,
    ) -> anyhow::Result<Vec<(PostId, Post, PostVisibility, Option<String>)>> {
        let (raw, group_seeds, personas) = {
            let storage = self.storage.get().await;
            let posts = storage.get_feed()?;
            let seeds = storage.get_all_group_seeds_map().unwrap_or_default();
            let personas = storage.list_posting_identities().unwrap_or_default();
            (posts, seeds, personas)
        };
        Ok(Self::decrypt_posts(raw, &group_seeds, &personas))
    }

    pub async fn get_all_posts(
        &self,
    ) -> anyhow::Result<Vec<(PostId, Post, PostVisibility, Option<String>)>> {
        let (raw, group_seeds, personas) = {
            let storage = self.storage.get().await;
            let posts = storage.list_posts_reverse_chron()?;
            let seeds = storage.get_all_group_seeds_map().unwrap_or_default();
            let personas = storage.list_posting_identities().unwrap_or_default();
            (posts, seeds, personas)
        };
        Ok(Self::decrypt_posts(raw, &group_seeds, &personas))
    }

    pub async fn get_feed_page(
        &self,
        before_ms: Option<u64>,
        limit: usize,
    ) -> anyhow::Result<Vec<(PostId, Post, PostVisibility, Option<String>)>> {
        let (raw, group_seeds, personas) = {
            let storage = self.storage.get().await;
            let posts = storage.get_feed_page(before_ms, limit)?;
            let seeds = storage.get_all_group_seeds_map().unwrap_or_default();
            let personas = storage.list_posting_identities().unwrap_or_default();
            (posts, seeds, personas)
        };
        Ok(Self::decrypt_posts(raw, &group_seeds, &personas))
    }

    pub async fn get_all_posts_page(
        &self,
        before_ms: Option<u64>,
        limit: usize,
    ) -> anyhow::Result<Vec<(PostId, Post, PostVisibility, Option<String>)>> {
        let (raw, group_seeds, personas) = {
            let storage = self.storage.get().await;
            let posts = storage.list_posts_page(before_ms, limit)?;
            let seeds = storage.get_all_group_seeds_map().unwrap_or_default();
            let personas = storage.list_posting_identities().unwrap_or_default();
            (posts, seeds, personas)
        };
        Ok(Self::decrypt_posts(raw, &group_seeds, &personas))
    }

    /// Attempt to decrypt each post using all held posting identities as
    /// candidate recipients. The first persona whose secret matches a
    /// wrapped_key recipient wins; if none match, the post remains opaque.
    fn decrypt_posts(
        posts: Vec<(PostId, Post, PostVisibility)>,
        group_seeds: &std::collections::HashMap<(crate::types::GroupId, crate::types::GroupEpoch), ([u8; 32], [u8; 32])>,
        personas: &[crate::types::PostingIdentity],
    ) -> Vec<(PostId, Post, PostVisibility, Option<String>)> {
        posts
            .into_iter()
            .map(|(id, post, vis)| {
                let decrypted = match &vis {
                    PostVisibility::Public => None,
                    PostVisibility::Encrypted { recipients } => {
                        personas.iter().find_map(|pi| {
                            crypto::decrypt_post(
                                &post.content,
                                &pi.secret_seed,
                                &pi.node_id,
                                &post.author,
                                recipients,
                            )
                            .ok()
                            .flatten()
                        })
                    }
                    PostVisibility::GroupEncrypted { group_id, epoch, wrapped_cek } => {
                        group_seeds.get(&(*group_id, *epoch))
                            .and_then(|(seed, pubkey)| {
                                crypto::decrypt_group_post(
                                    &post.content,
                                    seed,
                                    pubkey,
                                    wrapped_cek,
                                ).ok()
                            })
                    }
                };
                (id, post, vis, decrypted)
            })
            .collect()
    }

    // ---- Follows ----

    pub async fn follow(&self, node_id: &NodeId) -> anyhow::Result<()> {
        let connected = self.network.is_connected(node_id).await;
        let storage = self.storage.get().await;
        storage.add_follow(node_id)?;

        // Upsert social route. v0.6.2: audience removed; only Follow exists.
        let addresses = storage.get_peer_record(node_id)?
            .map(|r| r.addresses).unwrap_or_default();
        let peer_addresses = storage.build_peer_addresses_for(node_id)?;
        let now = std::time::SystemTime::now().duration_since(std::time::UNIX_EPOCH)
            .unwrap_or_default().as_millis() as u64;
        let preferred_tree = storage.build_preferred_tree_for(node_id).unwrap_or_default();
        storage.upsert_social_route(&SocialRouteEntry {
            node_id: *node_id,
            addresses,
            peer_addresses,
            relation: SocialRelation::Follow,
            status: if connected { SocialStatus::Online } else { SocialStatus::Disconnected },
            last_connected_ms: 0,
            last_seen_ms: now,
            reach_method: ReachMethod::Direct,
            preferred_tree,
        })?;

        Ok(())
    }

    pub async fn unfollow(&self, node_id: &NodeId) -> anyhow::Result<()> {
        let storage = self.storage.get().await;
        storage.remove_follow(node_id)?;
        // v0.6.2: audience removed; unfollow drops the social route entirely.
        storage.remove_social_route(node_id)?;
        Ok(())
    }

    pub async fn list_follows(&self) -> anyhow::Result<Vec<NodeId>> {
        let storage = self.storage.get().await;
        storage.list_follows()
    }

    // ---- Profiles ----

    /// Set the default posting identity's profile (display_name, bio,
    /// preserving any existing avatar). Creates a signed
    /// `VisibilityIntent::Profile` post authored by the posting identity and
    /// propagates it via the normal neighbor-manifest CDN path. The locally
    /// stored profile row is keyed by the posting identity — peers who pull
    /// the profile post apply the same update on their side.
    pub async fn set_profile(&self, display_name: String, bio: String) -> anyhow::Result<PublicProfile> {
        let posting_id = self.default_posting_id;
        let posting_secret = self.default_posting_secret;

        // Preserve existing avatar if present.
        let avatar_cid = {
            let storage = self.storage.get().await;
            storage.get_profile(&posting_id).ok().flatten().and_then(|p| p.avatar_cid)
        };

        let profile_post = crate::profile::build_profile_post(
            &posting_id,
            &posting_secret,
            &display_name,
            &bio,
            avatar_cid,
        );
        let profile_post_id = crate::content::compute_post_id(&profile_post);
        let timestamp_ms = profile_post.timestamp_ms;

        // Store post with VisibilityIntent::Profile + apply (upserts profile row).
        {
            let storage = self.storage.get().await;
            storage.store_post_with_intent(
                &profile_post_id,
                &profile_post,
                &PostVisibility::Public,
                &VisibilityIntent::Profile,
            )?;
            crate::profile::apply_profile_post_if_applicable(
                &*storage,
                &profile_post,
                Some(&VisibilityIntent::Profile),
            )?;
        }

        // Propagate via neighbor-manifest header diffs like any other post.
        self.update_neighbor_manifests_as(
            &posting_id,
            &posting_secret,
            &profile_post_id,
            timestamp_ms,
        ).await;

        let profile = {
            let storage = self.storage.get().await;
            storage.get_profile(&posting_id)?
                .unwrap_or_else(|| PublicProfile {
                    node_id: posting_id,
                    display_name: display_name.clone(),
                    bio: bio.clone(),
                    updated_at: timestamp_ms,
                    anchors: vec![],
                    recent_peers: vec![],
                    preferred_peers: vec![],
                    public_visible: true,
                    avatar_cid,
                })
        };

        info!(
            posting_id = hex::encode(posting_id),
            profile_post_id = hex::encode(profile_post_id),
            "Published profile post"
        );
        Ok(profile)
    }

    pub async fn set_anchors(&self, anchors: Vec<NodeId>) -> anyhow::Result<PublicProfile> {
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        let recent_peers = self.current_recent_peers().await;
        let profile = {
            let storage = self.storage.get().await;
            let existing = storage.get_profile(&self.node_id)?;
            let (display_name, bio, public_visible, avatar_cid) = match existing {
                Some(p) => (p.display_name, p.bio, p.public_visible, p.avatar_cid),
                None => (String::new(), String::new(), true, None),
            };
            let preferred_peers = storage.list_preferred_peers().unwrap_or_default();

            let profile = PublicProfile {
                node_id: self.node_id,
                display_name,
                bio,
                updated_at: now,
                anchors,
                recent_peers,
                preferred_peers,
                public_visible,
                avatar_cid,
            };

            storage.store_profile(&profile)?;
            profile
        };

        let pushed = self.network.push_profile(&profile).await;
        if pushed > 0 {
            info!(pushed, "Pushed anchor update to peers");
        }

        Ok(profile)
    }

    pub async fn get_peer_anchors(&self, node_id: &NodeId) -> anyhow::Result<Vec<NodeId>> {
        let storage = self.storage.get().await;
        storage.get_peer_anchors(node_id)
    }

    pub async fn get_profile(&self, node_id: &NodeId) -> anyhow::Result<Option<PublicProfile>> {
        let storage = self.storage.get().await;
        storage.get_profile(node_id)
    }

    /// v0.6.2: the user's own display profile lives under the default
    /// posting identity (published as a signed Profile post), not the
    /// network NodeId.
    pub async fn my_profile(&self) -> anyhow::Result<Option<PublicProfile>> {
        let storage = self.storage.get().await;
        storage.get_profile(&self.default_posting_id)
    }

    pub async fn has_profile(&self) -> anyhow::Result<bool> {
        let storage = self.storage.get().await;
        Ok(storage.get_profile(&self.default_posting_id)?.is_some())
    }

    pub async fn get_display_name(&self, node_id: &NodeId) -> anyhow::Result<Option<String>> {
        let storage = self.storage.get().await;
        storage.get_display_name(node_id)
    }

    // ---- Blobs ----

    /// Get a blob by CID from local store.
    pub async fn get_blob(&self, cid: &[u8; 32]) -> anyhow::Result<Option<Vec<u8>>> {
        let data = self.blob_store.get(cid)?;
        if data.is_some() {
            let storage = self.storage.get().await;
            let _ = storage.touch_blob_access(cid);
        }
        Ok(data)
    }

    /// Decrypt a blob in the context of a post's visibility.
    /// Public posts pass through unchanged. Encrypted/group-encrypted posts decrypt with the CEK.
    fn decrypt_blob_for_post(
        &self,
        data: Vec<u8>,
        post: &Post,
        visibility: &PostVisibility,
        group_seeds: &std::collections::HashMap<([u8; 32], u64), ([u8; 32], [u8; 32])>,
    ) -> anyhow::Result<Option<Vec<u8>>> {
        match visibility {
            PostVisibility::Public => Ok(Some(data)),
            PostVisibility::Encrypted { recipients } => {
                let cek = crypto::unwrap_cek_for_recipient(
                    &self.default_posting_secret,
                    &self.node_id,
                    &post.author,
                    recipients,
                )?;
                match cek {
                    Some(cek) => {
                        let plaintext = crypto::decrypt_bytes_with_cek(&data, &cek)?;
                        Ok(Some(plaintext))
                    }
                    None => Ok(None),
                }
            }
            PostVisibility::GroupEncrypted { group_id, epoch, wrapped_cek } => {
                if let Some((seed, pubkey)) = group_seeds.get(&(*group_id, *epoch)) {
                    let cek = crypto::unwrap_group_cek(seed, pubkey, wrapped_cek)?;
                    let plaintext = crypto::decrypt_bytes_with_cek(&data, &cek)?;
                    Ok(Some(plaintext))
                } else {
                    Ok(None)
                }
            }
        }
    }

    /// Get a blob by CID, decrypting it in the context of the given post.
    /// For public posts, returns raw blob data. For encrypted posts, decrypts with the post's CEK.
    pub async fn get_blob_for_post(
        &self,
        cid: &[u8; 32],
        post_id: &PostId,
    ) -> anyhow::Result<Option<Vec<u8>>> {
        // Get raw blob data (local — no lock needed)
        let raw_data = match self.blob_store.get(cid)? {
            Some(d) => d,
            None => return Ok(None),
        };

        // Single lock acquisition for all DB reads
        let (post, visibility, group_seeds) = {
            let storage = self.storage.get().await;
            let _ = storage.touch_blob_access(cid);
            match storage.get_post_with_visibility(post_id)? {
                Some((post, vis)) => {
                    let seeds = if matches!(vis, PostVisibility::GroupEncrypted { .. }) {
                        storage.get_all_group_seeds_map().unwrap_or_default()
                    } else {
                        std::collections::HashMap::new()
                    };
                    (post, vis, seeds)
                }
                None => return Ok(Some(raw_data)), // No post context — return raw
            }
        };
        // Lock released — decrypt without lock
        match &visibility {
            PostVisibility::Public => Ok(Some(raw_data)),
            _ => self.decrypt_blob_for_post(raw_data, &post, &visibility, &group_seeds),
        }
    }

    /// Prefetch blobs for recently synced posts from a peer.
    /// Scans recent posts (newest first) for missing blobs, caps at 20 per cycle.
    /// Runs outside any locks.
    const MAX_PREFETCH_PER_CYCLE: usize = 20;

    pub async fn prefetch_blobs_from_peer(&self, peer_id: &NodeId) {
        // Brief lock: get post IDs and their attachment info
        let posts_with_atts: Vec<(PostId, NodeId, Vec<crate::types::Attachment>)> = {
            let storage = self.storage.get().await;
            let post_ids = storage.list_post_ids().unwrap_or_default();
            let mut result = Vec::new();
            for pid in post_ids {
                if result.len() >= Self::MAX_PREFETCH_PER_CYCLE { break; }
                if let Ok(Some(post)) = storage.get_post(&pid) {
                    if !post.attachments.is_empty() {
                        result.push((pid, post.author, post.attachments.clone()));
                    }
                }
            }
            result
        };
        // Lock released — check blob store and filter without lock
        let mut missing: Vec<(PostId, NodeId, Vec<crate::types::Attachment>)> = Vec::new();
        let mut total_missing = 0usize;
        for (pid, author, atts) in posts_with_atts {
            if total_missing >= Self::MAX_PREFETCH_PER_CYCLE { break; }
            let missing_atts: Vec<_> = atts.into_iter()
                .filter(|a| !self.blob_store.has(&a.cid))
                .collect();
            if !missing_atts.is_empty() {
                total_missing += missing_atts.len();
                missing.push((pid, author, missing_atts));
            }
        }

        if missing.is_empty() {
            return;
        }

        let mut fetched = 0usize;
        for (post_id, author, attachments) in &missing {
            for att in attachments {
                if fetched >= Self::MAX_PREFETCH_PER_CYCLE { break; }
                match self.fetch_blob_with_fallback(
                    &att.cid, post_id, author, &att.mime_type, 0,
                ).await {
                    Ok(Some(_)) => { fetched += 1; }
                    Ok(None) => {}
                    Err(e) => {
                        tracing::debug!(
                            cid = hex::encode(att.cid),
                            error = %e,
                            "Blob prefetch failed"
                        );
                    }
                }
            }
        }
        if fetched > 0 {
            tracing::info!(fetched, peer = hex::encode(peer_id), "Prefetched blobs after sync");
        }
    }

    /// Check if a blob exists locally.
    pub fn has_blob(&self, cid: &[u8; 32]) -> bool {
        self.blob_store.has(cid)
    }

    /// Fetch a blob from a peer, storing it locally and recording CDN metadata.
    pub async fn fetch_blob_from_peer(
        &self,
        cid: &[u8; 32],
        from_peer: &NodeId,
        post_id: &PostId,
        author: &NodeId,
        mime_type: &str,
        created_at: u64,
    ) -> anyhow::Result<Option<Vec<u8>>> {
        // Check local first
        if let Some(data) = self.blob_store.get(cid)? {
            return Ok(Some(data));
        }

        // Fetch with CDN metadata
        let (data, response) = self.network.fetch_blob_full(cid, from_peer).await?;
        if let Some(ref data) = data {
            // Store blob locally
            self.blob_store.store(cid, data)?;
            let storage = self.storage.get().await;
            storage.record_blob(cid, post_id, author, data.len() as u64, mime_type, created_at)?;

            // Store AuthorManifest if provided (extract from CdnManifest wrapper)
            if let Some(ref cdn_manifest) = response.manifest {
                if crypto::verify_manifest_signature(&cdn_manifest.author_manifest) {
                    let author_json = serde_json::to_string(&cdn_manifest.author_manifest).unwrap_or_default();
                    let _ = storage.store_cdn_manifest(
                        cid,
                        &author_json,
                        &cdn_manifest.author_manifest.author,
                        cdn_manifest.author_manifest.updated_at,
                    );
                }
            }

            // Record upstream source
            let source_addrs: Vec<String> = response.manifest.as_ref()
                .map(|m| m.host_addresses.clone())
                .unwrap_or_default();
            let _ = storage.touch_file_holder(
                cid,
                from_peer,
                &source_addrs,
                crate::storage::HolderDirection::Received,
            );
        }
        Ok(data)
    }

    /// Fetch a blob with CDN-aware cascade, preferring non-anchor sources to save anchor
    /// delivery budget:
    /// 1. Local → 2. Existing upstream → 3. Lateral peers (non-anchor first)
    /// → 4. Replicas → 5. Author → 6. Redirect peers
    /// Anchors are deprioritized at each step via storage-level ordering.
    pub async fn fetch_blob_with_fallback(
        &self,
        cid: &[u8; 32],
        post_id: &PostId,
        author: &NodeId,
        mime_type: &str,
        created_at: u64,
    ) -> anyhow::Result<Option<Vec<u8>>> {
        // 1. Check local
        if let Some(data) = self.blob_store.get(cid)? {
            let storage = self.storage.get().await;
            let _ = storage.touch_blob_access(cid);
            return Ok(Some(data));
        }

        // Collect redirect peers from responses in case we need them later
        let mut redirect_peers: Vec<crate::types::PeerWithAddress> = Vec::new();

        // 2. Try known holders (up to 5 most-recent peers we've interacted
        //    with about this file).
        let known_holders = {
            let storage = self.storage.get().await;
            storage.get_file_holders(cid).unwrap_or_default()
        };
        for (holder_nid, _addrs) in &known_holders {
            match self.fetch_blob_from_peer(cid, holder_nid, post_id, author, mime_type, created_at).await {
                Ok(Some(data)) => return Ok(Some(data)),
                Ok(None) => {}
                Err(e) => warn!(error = %e, "blob fetch from known holder failed"),
            }
        }

        // 3. Lateral N0-N2: mesh peers + N2 peers who have the author's posts
        //    (sorted by get_lateral_blob_sources: non-anchors first)
        let lateral_sources = {
            let storage = self.storage.get().await;
            storage.get_lateral_blob_sources(author, post_id).unwrap_or_default()
        };
        for lateral in lateral_sources {
            if lateral == *author {
                continue; // Author tried separately below
            }
            match self.network.fetch_blob_full(cid, &lateral).await {
                Ok((Some(data), response)) => {
                    self.blob_store.store(cid, &data)?;
                    let storage = self.storage.get().await;
                    storage.record_blob(cid, post_id, author, data.len() as u64, mime_type, created_at)?;
                    if let Some(ref cdn_manifest) = response.manifest {
                        if crypto::verify_manifest_signature(&cdn_manifest.author_manifest) {
                            let author_json = serde_json::to_string(&cdn_manifest.author_manifest).unwrap_or_default();
                            let _ = storage.store_cdn_manifest(cid, &author_json, &cdn_manifest.author_manifest.author, cdn_manifest.author_manifest.updated_at);
                        }
                    }
                    let _ = storage.touch_file_holder(
                        cid,
                        &lateral,
                        &[],
                        crate::storage::HolderDirection::Received,
                    );
                    return Ok(Some(data));
                }
                Ok((None, response)) => {
                    redirect_peers.extend(response.cdn_redirect_peers);
                }
                Err(e) => warn!(peer = hex::encode(lateral), error = %e, "lateral blob fetch failed"),
            }
        }

        // 4. Try replica peers (before author — replicas are often closer/cheaper)
        let replicas = {
            let storage = self.storage.get().await;
            storage.get_replica_peers(post_id, 3_600_000)?
        };
        for replica in replicas {
            match self.fetch_blob_from_peer(cid, &replica, post_id, author, mime_type, created_at).await {
                Ok(Some(data)) => return Ok(Some(data)),
                Ok(None) => {}
                Err(e) => warn!(peer = hex::encode(replica), error = %e, "blob fetch from replica failed"),
            }
        }

        // 5. Try author
        match self.fetch_blob_from_peer(cid, author, post_id, author, mime_type, created_at).await {
            Ok(Some(data)) => return Ok(Some(data)),
            Ok(None) => {}
            Err(e) => warn!(error = %e, "blob fetch from author failed"),
        }

        // 6. Try redirect peers (from any step that returned cdn_redirect_peers)
        for rp in &redirect_peers {
            if let Ok(nid_bytes) = hex::decode(&rp.n) {
                if let Ok(nid) = <[u8; 32]>::try_from(nid_bytes.as_slice()) {
                    match self.fetch_blob_from_peer(cid, &nid, post_id, author, mime_type, created_at).await {
                        Ok(Some(data)) => return Ok(Some(data)),
                        Ok(None) => {}
                        Err(e) => warn!(peer = &rp.n, error = %e, "redirect blob fetch failed"),
                    }
                }
            }
        }

        Ok(None)
    }

    // ---- Circles ----

    pub async fn create_circle(&self, name: String) -> anyhow::Result<()> {
        let storage = self.storage.get().await;
        storage.create_circle(&name)?;
        drop(storage);
        self.create_group_key_for_circle(&name).await?;
        Ok(())
    }

    pub async fn delete_circle(&self, name: String) -> anyhow::Result<()> {
        let storage = self.storage.get().await;
        // Delete group key and associated data
        if let Ok(Some(gk)) = storage.get_group_key_by_circle(&name) {
            let _ = storage.delete_group_key(&gk.group_id);
        }
        storage.delete_circle(&name)
    }

    pub async fn add_to_circle(&self, circle_name: String, node_id: NodeId) -> anyhow::Result<()> {
        {
            let storage = self.storage.get().await;
            storage.add_circle_member(&circle_name, &node_id)?;
        }

        // Wrap current group key for new member and distribute
        let distribute_payload = {
            let storage = self.storage.get().await;
            if let Ok(Some(gk)) = storage.get_group_key_by_circle(&circle_name) {
                if gk.admin == self.node_id {
                    if let Ok(Some(seed)) = storage.get_group_seed(&gk.group_id, gk.epoch) {
                        match crypto::wrap_group_key_for_member(&self.default_posting_secret, &node_id, &seed) {
                            Ok(wrapped) => {
                                let mk = crate::types::GroupMemberKey {
                                    member: node_id,
                                    epoch: gk.epoch,
                                    wrapped_group_key: wrapped,
                                };
                                let _ = storage.store_group_member_key(&gk.group_id, &mk);
                                Some(crate::protocol::GroupKeyDistributePayload {
                                    group_id: gk.group_id,
                                    circle_name: circle_name.clone(),
                                    epoch: gk.epoch,
                                    group_public_key: gk.group_public_key,
                                    admin: self.node_id,
                                    member_keys: vec![mk],
                                })
                            }
                            Err(e) => {
                                warn!(error = %e, "Failed to wrap group key for new member");
                                None
                            }
                        }
                    } else { None }
                } else { None }
            } else { None }
        };

        if let Some(payload) = distribute_payload {
            self.network.push_group_key(&node_id, &payload).await;
        }

        Ok(())
    }

    pub async fn remove_from_circle(
        &self,
        circle_name: String,
        node_id: NodeId,
    ) -> anyhow::Result<()> {
        {
            let storage = self.storage.get().await;
            storage.remove_circle_member(&circle_name, &node_id)?;
        }

        // Rotate group key if we're the admin
        self.rotate_group_key(&circle_name).await;

        Ok(())
    }

    /// Create a group key for a circle (called on circle creation).
    async fn create_group_key_for_circle(&self, circle_name: &str) -> anyhow::Result<()> {
        let (seed, pubkey) = crypto::generate_group_keypair();
        let group_id = crypto::compute_group_id(&pubkey);
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        let record = crate::types::GroupKeyRecord {
            group_id,
            circle_name: circle_name.to_string(),
            epoch: 1,
            group_public_key: pubkey,
            admin: self.node_id,
            created_at: now,
        };

        let storage = self.storage.get().await;
        storage.create_group_key(&record, Some(&seed))?;
        storage.store_group_seed(&group_id, 1, &seed)?;

        // Wrap for ourselves
        let self_wrapped = crypto::wrap_group_key_for_member(&self.default_posting_secret, &self.node_id, &seed)?;
        let self_mk = crate::types::GroupMemberKey {
            member: self.node_id,
            epoch: 1,
            wrapped_group_key: self_wrapped,
        };
        storage.store_group_member_key(&group_id, &self_mk)?;

        // Wrap for existing circle members and distribute
        let members = storage.get_circle_members(circle_name)?;
        drop(storage);

        for member in &members {
            if *member == self.node_id {
                continue;
            }
            match crypto::wrap_group_key_for_member(&self.default_posting_secret, member, &seed) {
                Ok(wrapped) => {
                    let mk = crate::types::GroupMemberKey {
                        member: *member,
                        epoch: 1,
                        wrapped_group_key: wrapped,
                    };
                    {
                        let storage = self.storage.get().await;
                        let _ = storage.store_group_member_key(&group_id, &mk);
                    }
                    let payload = crate::protocol::GroupKeyDistributePayload {
                        group_id,
                        circle_name: circle_name.to_string(),
                        epoch: 1,
                        group_public_key: pubkey,
                        admin: self.node_id,
                        member_keys: vec![mk],
                    };
                    self.network.push_group_key(member, &payload).await;
                }
                Err(e) => {
                    warn!(member = hex::encode(member), error = %e, "Failed to wrap group key for member");
                }
            }
        }

        info!(circle = %circle_name, group_id = hex::encode(group_id), "Created group key for circle");
        Ok(())
    }

    /// Rotate the group key for a circle (called on member removal).
    async fn rotate_group_key(&self, circle_name: &str) {
        let rotate_result = {
            let storage = self.storage.get().await;
            let gk = match storage.get_group_key_by_circle(circle_name) {
                Ok(Some(gk)) if gk.admin == self.node_id => gk,
                _ => return,
            };
            let remaining_members = match storage.get_circle_members(circle_name) {
                Ok(m) => m,
                Err(_) => return,
            };
            // Always include ourselves
            let mut all_members = remaining_members;
            if !all_members.contains(&self.node_id) {
                all_members.push(self.node_id);
            }
            match crypto::rotate_group_key(&self.default_posting_secret, gk.epoch, &all_members) {
                Ok((new_seed, new_pubkey, new_epoch, member_keys)) => {
                    Some((gk.group_id, new_seed, new_pubkey, new_epoch, member_keys, circle_name.to_string()))
                }
                Err(e) => {
                    warn!(error = %e, "Failed to rotate group key");
                    None
                }
            }
        };

        if let Some((group_id, new_seed, new_pubkey, new_epoch, member_keys, circle_name)) = rotate_result {
            // Update storage
            {
                let storage = self.storage.get().await;
                let _ = storage.update_group_epoch(&group_id, new_epoch, &new_pubkey, Some(&new_seed));
                let _ = storage.store_group_seed(&group_id, new_epoch, &new_seed);
                for mk in &member_keys {
                    let _ = storage.store_group_member_key(&group_id, mk);
                }
            }

            // Distribute to each member
            for mk in &member_keys {
                if mk.member == self.node_id {
                    continue;
                }
                let payload = crate::protocol::GroupKeyDistributePayload {
                    group_id,
                    circle_name: circle_name.clone(),
                    epoch: new_epoch,
                    group_public_key: new_pubkey,
                    admin: self.node_id,
                    member_keys: vec![mk.clone()],
                };
                self.network.push_group_key(&mk.member, &payload).await;
            }

            info!(circle = %circle_name, epoch = new_epoch, "Rotated group key");
        }
    }

    pub async fn list_circles(&self) -> anyhow::Result<Vec<Circle>> {
        let storage = self.storage.get().await;
        storage.list_circles()
    }

    // ---- Circle Profiles ----

    /// Set a circle profile: store locally, encrypt with group key, push to connected peers.
    pub async fn set_circle_profile(
        &self,
        circle_name: String,
        display_name: String,
        bio: String,
        avatar_cid: Option<[u8; 32]>,
    ) -> anyhow::Result<crate::types::CircleProfile> {
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        let cp = crate::types::CircleProfile {
            author: self.default_posting_id,
            circle_name: circle_name.clone(),
            display_name,
            bio,
            avatar_cid,
            updated_at: now,
        };

        // Get group key for this circle
        let (encrypted_payload, wrapped_cek, group_id, epoch) = {
            let storage = self.storage.get().await;
            // Verify circle exists
            let circles = storage.list_circles()?;
            if !circles.iter().any(|c| c.name == circle_name) {
                anyhow::bail!("circle '{}' does not exist", circle_name);
            }

            let gk = storage.get_group_key_by_circle(&circle_name)?
                .ok_or_else(|| anyhow::anyhow!("no group key for circle '{}'", circle_name))?;

            if gk.admin != self.node_id {
                anyhow::bail!("not admin of circle '{}'", circle_name);
            }

            let seed = storage.get_group_seed(&gk.group_id, gk.epoch)?
                .ok_or_else(|| anyhow::anyhow!("group seed not found for circle '{}'", circle_name))?;

            // Encrypt circle profile as JSON
            let json = serde_json::to_string(&cp)?;
            let (encrypted, wrapped) = crypto::encrypt_post_for_group(&json, &seed, &gk.group_public_key)?;

            // Store plaintext + encrypted form
            storage.set_circle_profile(&cp)?;
            storage.store_remote_circle_profile(
                &self.node_id,
                &circle_name,
                &cp,
                &encrypted,
                &wrapped,
                &gk.group_id,
                gk.epoch,
            )?;

            (encrypted, wrapped, gk.group_id, gk.epoch)
        };

        // Push to all connected mesh peers
        let payload = crate::protocol::CircleProfileUpdatePayload {
            author: self.default_posting_id,
            circle_name,
            group_id,
            epoch,
            encrypted_payload,
            wrapped_cek,
            updated_at: now,
        };
        let pushed = self.network.push_circle_profile(&payload).await;
        if pushed > 0 {
            info!(pushed, "Pushed circle profile update to peers");
        }

        Ok(cp)
    }

    /// Delete a circle profile and push tombstone.
    pub async fn delete_circle_profile(&self, circle_name: String) -> anyhow::Result<()> {
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        let payload = {
            let storage = self.storage.get().await;
            let gk = storage.get_group_key_by_circle(&circle_name)?
                .ok_or_else(|| anyhow::anyhow!("no group key for circle '{}'", circle_name))?;
            let seed = storage.get_group_seed(&gk.group_id, gk.epoch)?
                .ok_or_else(|| anyhow::anyhow!("group seed not found"))?;

            // Encrypt empty string as tombstone
            let (encrypted, wrapped) = crypto::encrypt_post_for_group("", &seed, &gk.group_public_key)?;

            storage.delete_circle_profile(&self.node_id, &circle_name)?;

            crate::protocol::CircleProfileUpdatePayload {
                author: self.default_posting_id,
                circle_name,
                group_id: gk.group_id,
                epoch: gk.epoch,
                encrypted_payload: encrypted,
                wrapped_cek: wrapped,
                updated_at: now,
            }
        };

        self.network.push_circle_profile(&payload).await;
        Ok(())
    }

    /// Set public_visible flag and push profile update.
    pub async fn set_public_visible(&self, visible: bool) -> anyhow::Result<()> {
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        let recent_peers = self.current_recent_peers().await;
        let profile = {
            let storage = self.storage.get().await;
            let existing = storage.get_profile(&self.node_id)?;
            let (display_name, bio, avatar_cid) = match existing {
                Some(p) => (p.display_name, p.bio, p.avatar_cid),
                None => (String::new(), String::new(), None),
            };
            let existing_anchors = storage.get_peer_anchors(&self.node_id).unwrap_or_default();
            let preferred_peers = storage.list_preferred_peers().unwrap_or_default();

            let profile = PublicProfile {
                node_id: self.node_id,
                display_name,
                bio,
                updated_at: now,
                anchors: existing_anchors,
                recent_peers,
                preferred_peers,
                public_visible: visible,
                avatar_cid,
            };

            storage.store_profile(&profile)?;
            profile
        };

        self.network.push_profile(&profile).await;
        Ok(())
    }

    /// Resolve display info for any peer, taking circle profiles into account.
    pub async fn resolve_display_name(
        &self,
        author: &NodeId,
    ) -> anyhow::Result<(String, String, Option<[u8; 32]>)> {
        let storage = self.storage.get().await;
        storage.resolve_display_for_peer(author, &self.node_id)
    }

    /// Get our own circle profile for a given circle.
    pub async fn get_circle_profile(
        &self,
        circle_name: &str,
    ) -> anyhow::Result<Option<crate::types::CircleProfile>> {
        let storage = self.storage.get().await;
        storage.get_circle_profile(&self.node_id, circle_name)
    }

    /// Get the public_visible setting for our own profile.
    pub async fn get_public_visible(&self) -> anyhow::Result<bool> {
        let storage = self.storage.get().await;
        Ok(storage
            .get_profile(&self.node_id)?
            .map(|p| p.public_visible)
            .unwrap_or(true))
    }

    // ---- Settings ----

    /// Get a setting value by key.
    pub async fn get_setting(&self, key: &str) -> anyhow::Result<Option<String>> {
        let storage = self.storage.get().await;
        storage.get_setting(key)
    }

    /// Set a setting value (upsert).
    pub async fn set_setting(&self, key: &str, value: &str) -> anyhow::Result<()> {
        let storage = self.storage.get().await;
        storage.set_setting(key, value)
    }

    // ---- Cache stats & pressure ----

    /// Get cache statistics: (used_bytes, max_bytes, blob_count).
    /// max_bytes comes from the `cache_size_bytes` setting (default 1 GB, 0 = unlimited).
    pub async fn get_cache_stats(&self) -> anyhow::Result<(u64, u64, u64)> {
        let storage = self.storage.get().await;
        let used = storage.total_blob_bytes()?;
        let count = storage.count_blobs()?;
        let max_str = storage.get_setting("cache_size_bytes")?.unwrap_or_default();
        let max: u64 = max_str.parse().unwrap_or(1_073_741_824);
        Ok((used, max, count))
    }

    /// Compute cache pressure score (0-255).
    /// 0 = no pressure (plenty of room or cache empty).
    /// 255 = maximum pressure (lowest-priority blob is >72 h old).
    /// Scales linearly: 0 h → 0, 36 h → 128, 72 h → 255.
    pub async fn compute_cache_pressure(&self) -> anyhow::Result<u8> {
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        let staleness_ms = 3600 * 1000;

        let (candidates, follows) = {
            let storage = self.storage.get().await;
            let candidates = storage.get_eviction_candidates(staleness_ms)?;
            let follows = storage.list_follows().unwrap_or_default();
            (candidates, follows)
        };

        if candidates.is_empty() {
            return Ok(255); // Empty cache = max willingness to accept
        }

        // Filter to non-elevated blobs (not pinned, not own content, not followed author)
        let non_elevated: Vec<_> = candidates.iter().filter(|c| {
            !c.pinned && c.author != self.node_id && !follows.contains(&c.author)
        }).collect();

        if non_elevated.is_empty() {
            return Ok(255); // All blobs are elevated — plenty of room for new content
        }

        // Find the lowest priority (oldest/least-valuable) blob
        let mut min_priority = f64::MAX;
        let mut min_created_at = u64::MAX;
        for c in &non_elevated {
            let priority = self.compute_blob_priority(c, &follows, now);
            if priority < min_priority {
                min_priority = priority;
                min_created_at = c.created_at;
            }
        }

        // Scale based on age of the oldest non-elevated blob
        let age_hours = now.saturating_sub(min_created_at) as f64 / (3600.0 * 1000.0);
        let pressure = if age_hours >= 72.0 {
            255
        } else {
            ((age_hours / 72.0) * 255.0) as u8
        };

        Ok(pressure)
    }

    // ---- Seen engagement tracking ----

    /// Get seen engagement counts for a post.
    pub async fn get_seen_engagement(&self, post_id: &PostId) -> anyhow::Result<(u32, u32)> {
        let storage = self.storage.get().await;
        storage.get_seen_engagement(post_id)
    }

    /// Mark a post's engagement as seen (upsert).
    pub async fn set_seen_engagement(&self, post_id: &PostId, react_count: u32, comment_count: u32) -> anyhow::Result<()> {
        let storage = self.storage.get().await;
        storage.set_seen_engagement(post_id, react_count, comment_count)
    }

    /// Get last-read timestamp for a conversation partner.
    pub async fn get_last_read_message(&self, partner_id: &NodeId) -> anyhow::Result<u64> {
        let storage = self.storage.get().await;
        storage.get_last_read_message(partner_id)
    }

    /// Mark a conversation as read up to the given timestamp.
    pub async fn set_last_read_message(&self, partner_id: &NodeId, timestamp_ms: u64) -> anyhow::Result<()> {
        let storage = self.storage.get().await;
        storage.set_last_read_message(partner_id, timestamp_ms)
    }

    // ---- Delete / Revocation ----

    pub async fn delete_post(&self, post_id: &PostId) -> anyhow::Result<()> {
        // Load the target post and the posting identity of its author. Only
        // the author can delete their own content, so the signing key must be
        // one we hold in posting_identities.
        let (target_author, author_secret) = {
            let storage = self.storage.get().await;
            let post = storage
                .get_post(post_id)?
                .ok_or_else(|| anyhow::anyhow!("post not found"))?;
            let pi = storage
                .get_posting_identity(&post.author)?
                .ok_or_else(|| anyhow::anyhow!("cannot delete: not authored by a persona on this device"))?;
            (pi.node_id, pi.secret_seed)
        };

        // Build the control-delete post signed by the target's author.
        let control_post = crate::control::build_delete_control_post(
            &target_author,
            &author_secret,
            post_id,
        );
        let control_post_id = crate::content::compute_post_id(&control_post);
        let now = control_post.timestamp_ms;

        // Clean up blob storage local-side. Blobs in remote holders become
        // orphans and get evicted naturally via LRU — BlobDeleteNotice is
        // gone in v0.6.2.
        let blob_cids = {
            let storage = self.storage.get().await;
            let cids = storage.delete_blobs_for_post(post_id)?;
            for cid in &cids {
                let _ = storage.cleanup_cdn_for_blob(cid);
            }
            cids
        };
        for cid in &blob_cids {
            if let Err(e) = self.blob_store.delete(cid) {
                warn!(cid = hex::encode(cid), error = %e, "Failed to delete blob file");
            }
        }

        // Store the control post locally with VisibilityIntent::Control so
        // feeds filter it and propagation queries find it. Apply the op under
        // the same guard so delete recording + target cleanup happen with the
        // control-post insert atomically.
        {
            let storage = self.storage.get().await;
            storage.store_post_with_intent(
                &control_post_id,
                &control_post,
                &PostVisibility::Public,
                &VisibilityIntent::Control,
            )?;
            crate::control::apply_control_post_if_applicable(
                &*storage,
                &control_post,
                Some(&VisibilityIntent::Control),
            )?;
        }

        // Propagate via the normal neighbor-manifest CDN path: include the
        // control post in the author's other posts' `following_posts` lists
        // and push manifest diffs to their file_holders. Peers who follow
        // any of the author's posts pick up the control post and apply it.
        self.update_neighbor_manifests_as(
            &target_author,
            &author_secret,
            &control_post_id,
            now,
        ).await;

        info!(
            post_id = hex::encode(post_id),
            control_post_id = hex::encode(control_post_id),
            blobs_removed = blob_cids.len(),
            "Deleted post via control post",
        );
        Ok(())
    }

    pub async fn revoke_post_access(
        &self,
        post_id: &PostId,
        revoked: &NodeId,
        mode: RevocationMode,
    ) -> anyhow::Result<Option<PostId>> {
        let (post, visibility) = {
            let storage = self.storage.get().await;
            storage
                .get_post_with_visibility(post_id)?
                .ok_or_else(|| anyhow::anyhow!("post not found"))?
        };

        if post.author != self.node_id {
            anyhow::bail!("cannot revoke: you are not the author");
        }

        let existing_recipients = match &visibility {
            PostVisibility::Public => anyhow::bail!("cannot revoke access on a public post"),
            PostVisibility::Encrypted { recipients } => recipients,
            PostVisibility::GroupEncrypted { .. } => {
                anyhow::bail!("cannot revoke individual access on a group-encrypted post; remove from circle instead")
            }
        };

        let new_recipient_ids: Vec<NodeId> = existing_recipients
            .iter()
            .map(|wk| wk.recipient)
            .filter(|r| r != revoked)
            .collect();

        if new_recipient_ids.len() == existing_recipients.len() {
            anyhow::bail!("revoked node was not a recipient of this post");
        }

        match mode {
            RevocationMode::SyncAccessList => {
                let new_wrapped = crypto::rewrap_visibility(
                    &self.default_posting_secret,
                    &self.node_id,
                    existing_recipients,
                    &new_recipient_ids,
                )?;
                let new_vis = PostVisibility::Encrypted {
                    recipients: new_wrapped,
                };
                {
                    let storage = self.storage.get().await;
                    storage.update_post_visibility(post_id, &new_vis)?;
                }

                // Propagate via a signed control-visibility post rather than a
                // direct push. Only the target's author can make such a post.
                let author_secret = {
                    let s = self.storage.get().await;
                    s.get_posting_identity(&post.author)?
                        .map(|pi| pi.secret_seed)
                        .ok_or_else(|| anyhow::anyhow!("missing posting secret for post author"))?
                };
                let control_post = crate::control::build_visibility_control_post(
                    &post.author,
                    &author_secret,
                    post_id,
                    &new_vis,
                );
                let control_post_id = crate::content::compute_post_id(&control_post);
                let now = control_post.timestamp_ms;
                {
                    let storage = self.storage.get().await;
                    storage.store_post_with_intent(
                        &control_post_id,
                        &control_post,
                        &PostVisibility::Public,
                        &VisibilityIntent::Control,
                    )?;
                }
                self.update_neighbor_manifests_as(
                    &post.author,
                    &author_secret,
                    &control_post_id,
                    now,
                ).await;
                info!(post_id = hex::encode(post_id), control_post_id = hex::encode(control_post_id), "Revoked access (sync mode) via control post");
                Ok(None)
            }
            RevocationMode::ReEncrypt => {
                let (new_content, new_wrapped) = crypto::re_encrypt_post(
                    &post.content,
                    &self.default_posting_secret,
                    &self.node_id,
                    existing_recipients,
                    &new_recipient_ids,
                )?;
                let new_vis = PostVisibility::Encrypted {
                    recipients: new_wrapped,
                };

                let new_post = Post {
                    author: self.default_posting_id,
                    content: new_content,
                    attachments: post.attachments.clone(),
                    timestamp_ms: post.timestamp_ms,
                };
                let new_post_id = compute_post_id(&new_post);

                {
                    let storage = self.storage.get().await;
                    storage.store_post_with_visibility(&new_post_id, &new_post, &new_vis)?;
                }

                // delete_post already pushes the DeleteRecord.
                // Replacement post propagates via the CDN to remaining recipients.
                self.delete_post(post_id).await?;

                info!(
                    old_id = hex::encode(post_id),
                    new_id = hex::encode(new_post_id),
                    "Re-encrypted post (revoke)"
                );
                Ok(Some(new_post_id))
            }
        }
    }

    pub async fn revoke_circle_access(
        &self,
        circle_name: &str,
        revoked: &NodeId,
        mode: RevocationMode,
    ) -> anyhow::Result<usize> {
        let posts = {
            let storage = self.storage.get().await;
            storage.find_posts_by_circle_intent(circle_name, &self.node_id)?
        };

        let mut count = 0;
        for (post_id, _post, vis) in &posts {
            if let PostVisibility::Encrypted { recipients } = vis {
                if recipients.iter().any(|wk| &wk.recipient == revoked) {
                    match self.revoke_post_access(post_id, revoked, mode).await {
                        Ok(_) => count += 1,
                        Err(e) => {
                            warn!(
                                post_id = hex::encode(post_id),
                                error = %e,
                                "Failed to revoke post access"
                            );
                        }
                    }
                }
            }
        }

        info!(circle = circle_name, count, "Revoked circle access");
        Ok(count)
    }

    pub async fn get_redundancy_summary(&self) -> anyhow::Result<(usize, usize, usize, usize)> {
        let storage = self.storage.get().await;
        storage.get_redundancy_summary(&self.node_id, 3_600_000)
    }

    // ---- Networking ----

    pub fn endpoint_addr(&self) -> iroh::EndpointAddr {
        self.network.endpoint_addr()
    }

    /// Connect to a peer by node ID using address resolution:
    /// 0. Already connected or has session → done
    /// 1. Social route cache → try cached address
    /// 2. Peers table → connect directly
    /// 3. N2/N3 lookup → ask tagged reporter for address
    /// 4. Worm lookup → fan-out search beyond N3
    /// 5. Relay introduction → coordinate hole punch via relay peer
    /// 6. Session relay fallback → pipe through intermediary
    pub async fn connect_by_node_id(&self, peer_id: NodeId) -> anyhow::Result<()> {
        if self.network.is_connected(&peer_id).await {
            return Ok(());
        }

        // Check if we already have a session connection
        if self.network.conn_handle().has_session(&peer_id).await {
            return Ok(());
        }

        // Check if this peer is known to be behind NAT / unreachable directly
        let skip_direct = self.network.conn_handle().is_likely_unreachable(&peer_id).await;

        // Step 0: Try social route cache (skipped for known-unreachable peers)
        if !skip_direct {
            let storage = self.storage.get().await;
            if let Some(route) = storage.get_social_route(&peer_id)? {
                // Try cached addresses directly
                for addr in &route.addresses {
                    let endpoint_id = match iroh::EndpointId::from_bytes(&peer_id) {
                        Ok(eid) => eid,
                        Err(_) => continue,
                    };
                    let ep_addr = iroh::EndpointAddr::from(endpoint_id).with_ip_addr(*addr);
                    drop(storage);
                    if self.network.connect_to_peer(peer_id, ep_addr).await.is_ok() {
                        info!(peer = hex::encode(peer_id), "Connected via social route cache");
                        return Ok(());
                    }
                    // Re-acquire lock for next iteration
                    break; // Only try first address from route directly
                }

                // Try peer_addresses: connect to their known peers and ask for target
                for pa in &route.peer_addresses {
                    if let Ok(pa_nid) = crate::parse_node_id_hex(&pa.n) {
                        if self.network.is_connected(&pa_nid).await {
                            // Already connected to this peer — ask them
                            let resolved = self.network.conn_handle().resolve_address(&peer_id).await.unwrap_or(None);
                            if let Some(addr_str) = resolved {
                                if let Ok((_nid, ep_addr)) = crate::parse_connect_string(
                                    &format!("{}@{}", hex::encode(peer_id), addr_str)
                                ) {
                                    if self.network.connect_to_peer(peer_id, ep_addr).await.is_ok() {
                                        info!(peer = hex::encode(peer_id), via = &pa.n[..12], "Connected via social route peer referral");
                                        return Ok(());
                                    }
                                }
                            }
                        } else if let Some(pa_addr_str) = pa.a.first() {
                            // Try connecting to the peer first, then ask
                            if let Ok(pa_sock) = pa_addr_str.parse::<std::net::SocketAddr>() {
                                let pa_eid = match iroh::EndpointId::from_bytes(&pa_nid) {
                                    Ok(eid) => eid,
                                    Err(_) => continue,
                                };
                                let pa_ep = iroh::EndpointAddr::from(pa_eid).with_ip_addr(pa_sock);
                                if self.network.connect_to_peer(pa_nid, pa_ep).await.is_ok() {
                                    let resolved = self.network.conn_handle().resolve_address(&peer_id).await.unwrap_or(None);
                                    if let Some(addr_str) = resolved {
                                        if let Ok((_nid, ep_addr)) = crate::parse_connect_string(
                                            &format!("{}@{}", hex::encode(peer_id), addr_str)
                                        ) {
                                            if self.network.connect_to_peer(peer_id, ep_addr).await.is_ok() {
                                                info!(peer = hex::encode(peer_id), via = &pa.n[..12], "Connected via social route peer referral (new conn)");
                                                return Ok(());
                                            }
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }

        // Steps 1-4: Direct connection attempts (skipped for known-unreachable peers)
        if !skip_direct {
            // Step 1: Try direct address from peers table
            if let Some(addr) = self.network.addr_from_storage(&peer_id).await {
                if self.network.connect_to_peer(peer_id, addr).await.is_ok() {
                    return Ok(());
                }
            }

            // Step 2-3: Try address resolution via N2/N3
            let resolved = self.network.conn_handle().resolve_address(&peer_id).await.unwrap_or(None);

            if let Some(addr_str) = resolved {
                if let Ok(addr) = crate::parse_connect_string(&format!("{}@{}", hex::encode(peer_id), addr_str)) {
                    if self.network.connect_to_peer(peer_id, addr.1).await.is_ok() {
                        return Ok(());
                    }
                }
            }

            // Step 4: Try worm lookup (fan-out search beyond N3)
            info!(peer = hex::encode(peer_id), "Trying worm lookup...");
            if let Ok(Some(wr)) = self.network.worm_lookup(&peer_id).await {
                if wr.node_id == peer_id {
                    if let Some(addr_str) = wr.addresses.first() {
                        if let Ok(addr) = crate::parse_connect_string(&format!("{}@{}", hex::encode(peer_id), addr_str)) {
                            if self.network.connect_to_peer(peer_id, addr.1).await.is_ok() {
                                return Ok(());
                            }
                        }
                    }
                } else {
                    info!(
                        target = hex::encode(peer_id),
                        found_via = hex::encode(wr.node_id),
                        "Worm found target via recent peer"
                    );
                    if let Some(addr_str) = wr.addresses.first() {
                        if let Ok(needle_addr) = crate::parse_connect_string(&format!("{}@{}", hex::encode(wr.node_id), addr_str)) {
                            if self.network.connect_to_peer(wr.node_id, needle_addr.1).await.is_ok() {
                                let resolved = self.network.conn_handle().resolve_address(&peer_id).await.unwrap_or(None);
                                if let Some(target_addr_str) = resolved {
                                    if let Ok(target_addr) = crate::parse_connect_string(&format!("{}@{}", hex::encode(peer_id), target_addr_str)) {
                                        if self.network.connect_to_peer(peer_id, target_addr.1).await.is_ok() {
                                            return Ok(());
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }

            // All direct attempts failed — mark peer as likely unreachable
            self.network.conn_handle().mark_unreachable(&peer_id);
        }

        // Step 6: Relay introduction — find relay peer(s) and request introduction
        {
            let on_cooldown = {
                let storage = self.storage.get().await;
                storage.is_relay_cooldown(&peer_id, 300_000).unwrap_or(false)
            };

            if !on_cooldown {
                let relay_candidates = self.network.conn_handle().find_relays_for(&peer_id).await;

                let mut had_capacity_reject = false;
                let mut last_intro_id: Option<crate::connection::IntroId> = None;
                let mut last_relay_peer: Option<NodeId> = None;
                let mut last_relay_available = false;

                for (relay_peer, ttl) in &relay_candidates {
                    info!(
                        target = hex::encode(peer_id),
                        relay = hex::encode(relay_peer),
                        ttl,
                        "Attempting relay introduction"
                    );

                    let intro_result = tokio::time::timeout(
                        std::time::Duration::from_secs(15),
                        self.network.send_relay_introduce_standalone(relay_peer, &peer_id, *ttl),
                    ).await;

                    match intro_result {
                        Ok(Ok(result)) if result.accepted => {
                            info!(
                                target = hex::encode(peer_id),
                                addrs = ?result.target_addresses,
                                relay_available = result.relay_available,
                                "Relay introduction accepted, attempting hole punch"
                            );

                            // Save for potential session relay fallback
                            last_intro_id = Some(result.intro_id);
                            last_relay_peer = Some(*relay_peer);
                            last_relay_available = result.relay_available;

                            // Try direct connection to target's addresses (hole punch with scanning)
                            let our_profile = self.network.conn_handle().our_nat_profile().await;
                            let peer_profile = {
                                let s = self.storage.get().await;
                                s.get_peer_nat_profile(&peer_id)
                            };
                            if let Some(conn) = crate::connection::hole_punch_with_scanning(
                                self.network.endpoint(),
                                &peer_id,
                                &result.target_addresses,
                                our_profile,
                                peer_profile,
                            ).await {
                                self.network.conn_handle().add_session(peer_id, conn, SessionReachMethod::HolePunch, None).await;
                                self.network.conn_handle().mark_reachable(&peer_id);
                                info!(peer = hex::encode(peer_id), "Connected via hole punch");
                                return Ok(());
                            }

                            // Intro accepted but hole punch failed — try session relay below
                            break;
                        }
                        Ok(Ok(result)) => {
                            let reason = result.reject_reason.as_deref().unwrap_or("unknown");
                            if reason.contains("capacity") {
                                debug!(
                                    relay = hex::encode(relay_peer),
                                    "Relay at capacity, trying next candidate"
                                );
                                had_capacity_reject = true;
                                continue; // Try next relay candidate
                            }
                            debug!(
                                target = hex::encode(peer_id),
                                reason,
                                "Relay introduction rejected"
                            );
                            // Target explicitly rejected — don't try more relays
                            break;
                        }
                        Ok(Err(e)) => {
                            debug!(error = %e, "Relay introduction failed, trying next candidate");
                            continue; // Network error — try next relay
                        }
                        Err(_) => {
                            debug!("Relay introduction timed out, trying next candidate");
                            continue; // Timeout — try next relay
                        }
                    }
                }

                // Step 7: Session relay fallback — if intro was accepted but hole punch failed
                if let (Some(intro_id), Some(relay_peer)) = (last_intro_id, last_relay_peer) {
                    if last_relay_available {
                        info!(
                            target = hex::encode(peer_id),
                            relay = hex::encode(relay_peer),
                            "Hole punch failed, attempting session relay"
                        );

                        match self.attempt_session_relay(&relay_peer, &peer_id, &intro_id).await {
                            Ok(()) => {
                                info!(peer = hex::encode(peer_id), "Connected via session relay");
                                return Ok(());
                            }
                            Err(e) => {
                                debug!(error = %e, "Session relay failed");
                            }
                        }
                    }
                }

                // Record cooldown on failure (skip if all rejections were capacity-related)
                if !relay_candidates.is_empty() && !had_capacity_reject {
                    let storage = self.storage.get().await;
                    let _ = storage.record_relay_miss(&peer_id);
                }
            }
        }

        anyhow::bail!(
            "cannot resolve address for peer {} (tried social routes, peers table, N2/N3, worm lookup, and relay introduction)",
            hex::encode(peer_id)
        )
    }

    /// Attempt to establish a session relay through an intermediary.
    async fn attempt_session_relay(
        &self,
        relay_peer: &NodeId,
        target: &NodeId,
        intro_id: &crate::connection::IntroId,
    ) -> anyhow::Result<()> {
        use crate::protocol::{
            write_typed_message, MessageType, SessionRelayPayload,
        };

        let relay_conn = self.network.conn_handle().get_connection(relay_peer).await
            .ok_or_else(|| anyhow::anyhow!("relay peer disconnected"))?;

        let (mut send, _recv) = relay_conn.open_bi().await?;

        let payload = SessionRelayPayload {
            intro_id: *intro_id,
            target: *target,
        };
        write_typed_message(&mut send, MessageType::SessionRelay, &payload).await?;

        self.network.conn_handle().add_session(*target, relay_conn, SessionReachMethod::Relayed, None).await;

        Ok(())
    }

    /// Worm lookup: fan-out search for a peer beyond the 3-hop discovery map.
    pub async fn worm_lookup(&self, target: &NodeId) -> anyhow::Result<Option<WormResult>> {
        self.network.worm_lookup(target).await
    }

    /// Connect to a peer and establish a mesh connection
    pub async fn sync_with(&self, peer_id: NodeId) -> anyhow::Result<()> {
        self.connect_by_node_id(peer_id).await?;
        // Reset last_sync_ms for this author so the responder sends ALL posts,
        // not just posts newer than our last sync timestamp.
        {
            let storage = self.storage.get().await;
            let _ = storage.update_follow_last_sync(&peer_id, 0);
        }
        let stats = self.network.conn_handle().pull_from_peer(&peer_id).await?;
        // Also fetch engagement data (reactions, comments) for posts we hold
        let engagement = self.network.conn_handle().fetch_engagement_from_peer(&peer_id).await.unwrap_or(0);
        info!(
            peer = hex::encode(peer_id),
            posts = stats.posts_received,
            engagement_headers = engagement,
            "Sync complete"
        );
        // Prefetch blobs for posts we just received
        if stats.posts_received > 0 {
            self.prefetch_blobs_from_peer(&peer_id).await;
        }
        Ok(())
    }

    /// Connect to a peer using full address
    pub async fn sync_with_addr(&self, addr: iroh::EndpointAddr) -> anyhow::Result<()> {
        let peer_id = *addr.id.as_bytes();
        self.network.connect_to_peer(peer_id, addr).await?;
        let stats = self.network.conn_handle().pull_from_peer(&peer_id).await?;
        info!(
            peer = hex::encode(peer_id),
            posts = stats.posts_received,
            "Sync complete"
        );
        Ok(())
    }

    /// Pull from all connected peers
    pub async fn sync_all(&self) -> anyhow::Result<()> {
        let stats = self.network.pull_from_all().await?;
        info!(
            "Pull complete: {} posts from {} peers",
            stats.posts_received, stats.peers_pulled
        );
        Ok(())
    }

    pub async fn add_peer(&self, peer_id: NodeId) -> anyhow::Result<()> {
        let storage = self.storage.get().await;
        storage.add_peer(&peer_id)?;
        Ok(())
    }

    pub async fn list_peers(&self) -> anyhow::Result<Vec<NodeId>> {
        let storage = self.storage.get().await;
        storage.list_peers()
    }

    pub async fn list_peer_records(&self) -> anyhow::Result<Vec<PeerRecord>> {
        let storage = self.storage.get().await;
        storage.list_peer_records()
    }

    pub async fn list_bootstrap_anchors(&self) -> Vec<(NodeId, iroh::EndpointAddr)> {
        self.bootstrap_anchors.lock().await.clone()
    }

    /// Get connection info for display: (node_id, slot_kind, connected_at)
    pub async fn list_connections(&self) -> Vec<(NodeId, PeerSlotKind, u64)> {
        self.network.connection_info().await
    }

    pub async fn stats(&self) -> anyhow::Result<NodeStats> {
        let storage = self.storage.get().await;
        Ok(NodeStats {
            post_count: storage.post_count()?,
            peer_count: storage.list_peers()?.len(),
            follow_count: storage.list_follows()?.len(),
        })
    }

    /// Start the accept loop (run in background)
    pub fn start_accept_loop(&self) -> tokio::task::JoinHandle<anyhow::Result<()>> {
        let network = Arc::clone(&self.network);
        tokio::spawn(async move { network.run_accept_loop().await })
    }

    /// Start pull cycle: Protocol v4 tiered pull — 60s ticks, full pull on first tick,
    /// then only pull for stale authors (last_sync_ms > 4 hours old).
    pub fn start_pull_cycle(self: &Arc<Self>, _interval_secs: u64) -> tokio::task::JoinHandle<()> {
        let node = Arc::clone(self);
        tokio::spawn(async move {
            let mut interval =
                tokio::time::interval(std::time::Duration::from_secs(60));
            let mut is_first_tick = true;
            loop {
                interval.tick().await;

                if is_first_tick {
                    // Full pull on startup
                    let _ = node.network.pull_from_all().await;
                    is_first_tick = false;
                    // Prefetch after initial sync
                    let peers = node.network.conn_handle().connected_peers().await;
                    for peer_id in peers {
                        node.prefetch_blobs_from_peer(&peer_id).await;
                    }
                    continue;
                }

                // Tiered: only pull for stale authors (4-hour default)
                let stale_authors = {
                    let storage = node.storage.get().await;
                    storage.get_stale_follows(4 * 3600 * 1000).unwrap_or_default()
                };

                if stale_authors.is_empty() {
                    continue; // Most ticks skip — no stale authors
                }

                // Find a connected peer and pull
                let peers = node.network.conn_handle().connected_peers().await;
                if let Some(peer_id) = peers.first() {
                    match node.network.conn_handle().pull_from_peer(peer_id).await {
                        Ok(stats) => {
                            if stats.posts_received > 0 {
                                tracing::debug!(
                                    posts = stats.posts_received,
                                    "Tiered pull complete"
                                );
                                node.prefetch_blobs_from_peer(peer_id).await;
                            }
                        }
                        Err(e) => tracing::debug!(error = %e, "Tiered pull failed"),
                    }
                }
            }
        })
    }

    /// Start diff cycle: every interval_secs, broadcast N1/N2 changes to connected peers.
    pub fn start_diff_cycle(&self, interval_secs: u64) -> tokio::task::JoinHandle<()> {
        let network = Arc::clone(&self.network);
        let full_sync_interval = (4 * 60 * 60) / interval_secs; // every 4 hours
        tokio::spawn(async move {
            let mut interval =
                tokio::time::interval(std::time::Duration::from_secs(interval_secs));
            let mut tick_count: u64 = 0;
            loop {
                interval.tick().await;
                tick_count += 1;

                if tick_count % full_sync_interval == 0 {
                    // Full state re-broadcast every 4 hours to catch missed diffs
                    match network.broadcast_full_state().await {
                        Ok(count) => {
                            if count > 0 {
                                tracing::info!(count, "Full N1/N2 state broadcast (4h cycle)");
                            }
                        }
                        Err(e) => {
                            tracing::debug!(error = %e, "Full state broadcast failed");
                        }
                    }
                } else {
                    match network.broadcast_diff().await {
                        Ok(count) => {
                            if count > 0 {
                                tracing::debug!(count, "Broadcast routing diff");
                            }
                        }
                        Err(e) => {
                            tracing::debug!(error = %e, "Routing diff broadcast failed");
                        }
                    }
                }
            }
        })
    }

    /// Start rebalance cycle: every interval_secs, rebalance connection slots.
    pub fn start_rebalance_cycle(&self, interval_secs: u64) -> tokio::task::JoinHandle<()> {
        let network = Arc::clone(&self.network);
        let timer = Arc::clone(&self.last_rebalance_ms);
        tokio::spawn(async move {
            let mut interval =
                tokio::time::interval(std::time::Duration::from_secs(interval_secs));
            loop {
                interval.tick().await;
                let now = std::time::SystemTime::now()
                    .duration_since(std::time::UNIX_EPOCH)
                    .unwrap_or_default()
                    .as_millis() as u64;
                timer.store(now, AtomicOrdering::Relaxed);
                if let Err(e) = network.rebalance().await {
                    tracing::debug!(error = %e, "Rebalance failed");
                }
            }
        })
    }

    /// Start the reactive growth loop: wakes on signal, sequentially fills local
    /// slots with the most diverse N2 candidates. Each connection updates N2/N3
    /// knowledge before picking the next candidate.
    pub fn start_growth_loop(&self) -> tokio::task::JoinHandle<()> {
        let network = Arc::clone(&self.network);
        let (tx, rx) = tokio::sync::mpsc::channel(1);
        tokio::spawn(async move {
            network.set_growth_tx(tx.clone()).await;
            // Initial kick: bootstrap may have already populated N2 before this started
            let _ = tx.try_send(());
            network.run_growth_loop(rx).await;
        })
    }

    /// Start recovery loop: triggered when mesh drops below 2 connections.
    /// Immediately reconnects to anchors and requests referrals.
    pub fn start_recovery_loop(&self) -> tokio::task::JoinHandle<()> {
        let network = Arc::clone(&self.network);
        let storage = Arc::clone(&self.storage);
        let node_id = self.node_id;
        let alog = Arc::clone(&self.activity_log);
        let (tx, mut rx) = tokio::sync::mpsc::channel::<()>(1);
        tokio::spawn(async move {
            let log_evt = |level: ActivityLevel, cat: ActivityCategory, msg: String, peer: Option<NodeId>| {
                if let Ok(mut log) = alog.try_lock() { log.log(level, cat, msg, peer); }
            };
            network.set_recovery_tx(tx).await;
            while rx.recv().await.is_some() {
                tracing::info!("Recovery triggered: reconnecting to anchors");
                log_evt(ActivityLevel::Warn, ActivityCategory::Recovery, "Recovery triggered: mesh empty".into(), None);
                // Debounce: wait briefly for more disconnects to settle
                tokio::time::sleep(std::time::Duration::from_secs(2)).await;
                // Drain any queued signals
                while rx.try_recv().is_ok() {}

                // Gather anchors: known_anchors table, then anchor peers fallback
                let anchors: Vec<(crate::types::NodeId, Vec<std::net::SocketAddr>)> = {
                    let s = storage.get().await;
                    let known = s.list_known_anchors().unwrap_or_default();
                    if !known.is_empty() {
                        known
                    } else {
                        s.list_anchor_peers().unwrap_or_default()
                            .into_iter()
                            .map(|r| (r.node_id, r.addresses))
                            .collect()
                    }
                };

                for (anchor_nid, anchor_addrs) in &anchors {
                    if *anchor_nid == node_id { continue; }
                    // Connect to anchor (mesh or session fallback)
                    if !network.is_peer_connected_or_session(anchor_nid).await {
                        let endpoint_id = match iroh::EndpointId::from_bytes(anchor_nid) {
                            Ok(eid) => eid,
                            Err(_) => continue,
                        };
                        let mut addr = iroh::EndpointAddr::from(endpoint_id);
                        for sa in anchor_addrs {
                            addr = addr.with_ip_addr(*sa);
                        }
                        match network.connect_to_anchor(*anchor_nid, addr).await {
                            Ok(()) => {
                                log_evt(ActivityLevel::Info, ActivityCategory::Recovery, "Connected to anchor".into(), Some(*anchor_nid));
                            }
                            Err(e) => {
                                tracing::debug!(error = %e, "Recovery: anchor connect failed");
                                log_evt(ActivityLevel::Warn, ActivityCategory::Recovery, format!("Anchor connect failed: {}", e), Some(*anchor_nid));
                                continue;
                            }
                        }
                    }
                    // Register with anchor
                    let _ = network.send_anchor_register(anchor_nid).await;
                    // Request referrals
                    match network.request_anchor_referrals(anchor_nid).await {
                        Ok(referrals) => {
                            for referral in referrals {
                                if referral.node_id == node_id { continue; }
                                if let Some(addr_str) = referral.addresses.first() {
                                    let connect_str = format!(
                                        "{}@{}", hex::encode(referral.node_id), addr_str,
                                    );
                                    if let Ok((rid, raddr)) = crate::parse_connect_string(&connect_str) {
                                        match network.connect_to_peer(rid, raddr).await {
                                            Ok(()) => {
                                                tracing::info!(peer = hex::encode(rid), "Recovery: connected to referred peer");
                                                log_evt(ActivityLevel::Info, ActivityCategory::Recovery, "Connected to referred peer".into(), Some(rid));
                                            }
                                            Err(_) => {
                                                match network.connect_via_introduction(rid, *anchor_nid).await {
                                                    Ok(()) => {
                                                        tracing::info!(peer = hex::encode(rid), "Recovery: connected via hole punch");
                                                        log_evt(ActivityLevel::Info, ActivityCategory::Recovery, "Connected via hole punch".into(), Some(rid));
                                                    }
                                                    Err(e) => {
                                                        tracing::debug!(error = %e, peer = hex::encode(rid), "Recovery: hole punch failed");
                                                        log_evt(ActivityLevel::Warn, ActivityCategory::Recovery, format!("Hole punch failed: {}", e), Some(rid));
                                                    }
                                                }
                                            }
                                        }
                                    }
                                }
                            }
                        }
                        Err(e) => tracing::debug!(error = %e, "Recovery: referral request failed"),
                    }
                }
                let conn_count = network.connection_count().await;
                tracing::info!(connections = conn_count, "Recovery complete");
                log_evt(ActivityLevel::Info, ActivityCategory::Recovery, format!("Recovery complete, {} connections", conn_count), None);
            }
        })
    }

    /// Start social checkin cycle: every interval_secs, refresh stale social routes.
    /// Uses ephemeral connections if not persistently connected.
    pub fn start_social_checkin_cycle(&self, interval_secs: u64) -> tokio::task::JoinHandle<()> {
        let network = Arc::clone(&self.network);
        let storage = Arc::clone(&self.storage);
        tokio::spawn(async move {
            let mut interval =
                tokio::time::interval(std::time::Duration::from_secs(interval_secs));
            loop {
                interval.tick().await;
                let stale = {
                    let s = storage.get().await;
                    s.list_stale_social_routes(interval_secs as u64 * 1000).unwrap_or_default()
                };
                for route in stale {
                    let our_addrs: Vec<String> = network.endpoint_addr().ip_addrs()
                        .map(|s| s.to_string()).collect();
                    let result = network.send_social_checkin(
                        &route.node_id, &our_addrs, &[],
                    ).await;
                    match result {
                        Ok(reply) => {
                            let s = storage.get().await;
                            let addrs: Vec<std::net::SocketAddr> = reply.addresses.iter()
                                .filter_map(|a| a.parse().ok()).collect();
                            let _ = s.touch_social_route_connect(
                                &reply.node_id, &addrs, ReachMethod::Direct,
                            );
                            let _ = s.update_social_route_peer_addrs(
                                &reply.node_id, &reply.peer_addresses,
                            );
                        }
                        Err(e) => {
                            tracing::debug!(
                                peer = hex::encode(route.node_id),
                                error = %e,
                                "Social checkin failed"
                            );
                        }
                    }
                }
            }
        })
    }

    /// Register with all connected anchor peers. Returns count registered.
    pub async fn register_with_anchors(&self) -> usize {
        let conns = self.network.connection_info().await;
        let mut count = 0;
        for (nid, _, _) in &conns {
            if self.network.is_anchor_peer(nid).await {
                match self.network.send_anchor_register(nid).await {
                    Ok(()) => {
                        count += 1;
                        info!(anchor = hex::encode(nid), "Registered with anchor");
                    }
                    Err(e) => debug!(error = %e, anchor = hex::encode(nid), "Anchor register failed"),
                }
            }
        }
        count
    }

    /// Start anchor register cycle: periodically re-register with anchors and request referrals
    /// when connection count is low.
    pub fn start_anchor_register_cycle(&self, interval_secs: u64) -> tokio::task::JoinHandle<()> {
        let network = Arc::clone(&self.network);
        let storage = Arc::clone(&self.storage);
        let node_id = self.node_id;
        let alog = Arc::clone(&self.activity_log);
        let timer = Arc::clone(&self.last_anchor_register_ms);
        tokio::spawn(async move {
            let log_evt = |level: ActivityLevel, cat: ActivityCategory, msg: String, peer: Option<NodeId>| {
                if let Ok(mut log) = alog.try_lock() { log.log(level, cat, msg, peer); }
            };
            let mut interval =
                tokio::time::interval(std::time::Duration::from_secs(interval_secs));
            loop {
                interval.tick().await;
                let now = std::time::SystemTime::now()
                    .duration_since(std::time::UNIX_EPOCH)
                    .unwrap_or_default()
                    .as_millis() as u64;
                timer.store(now, AtomicOrdering::Relaxed);

                // Re-register with connected anchors (mesh + session)
                let conns = network.connection_info().await;
                let session_peers = network.session_peer_ids().await;
                let mut registered_anchors = std::collections::HashSet::new();
                // Mesh-connected anchors
                for (nid, _, _) in &conns {
                    if network.is_anchor_peer(nid).await {
                        match network.send_anchor_register(nid).await {
                            Ok(()) => {
                                log_evt(ActivityLevel::Info, ActivityCategory::Anchor, "Re-registered with anchor".into(), Some(*nid));
                                registered_anchors.insert(*nid);
                            }
                            Err(e) => {
                                tracing::debug!(error = %e, "Anchor re-register failed");
                                log_evt(ActivityLevel::Warn, ActivityCategory::Anchor, format!("Re-register failed: {}", e), Some(*nid));
                            }
                        }
                    }
                }
                // Session-connected anchors (e.g. anchor with full mesh)
                for nid in &session_peers {
                    if registered_anchors.contains(nid) { continue; }
                    if network.is_anchor_peer(nid).await {
                        match network.send_anchor_register(nid).await {
                            Ok(()) => {
                                log_evt(ActivityLevel::Info, ActivityCategory::Anchor, "Re-registered with anchor (session)".into(), Some(*nid));
                            }
                            Err(e) => {
                                tracing::debug!(error = %e, "Anchor session re-register failed");
                            }
                        }
                    }
                }

                // If few connections, try requesting referrals from known anchors
                let conn_count = network.connection_count().await;
                if conn_count < 10 {
                    log_evt(ActivityLevel::Info, ActivityCategory::Anchor, format!("Low connections ({}), requesting referrals", conn_count), None);
                    let known = {
                        let s = storage.get().await;
                        s.list_known_anchors().unwrap_or_default()
                    };
                    for (anchor_nid, anchor_addrs) in known {
                        if anchor_nid == node_id {
                            continue;
                        }
                        // Connect if not already connected (mesh or session)
                        if !network.is_peer_connected_or_session(&anchor_nid).await {
                            let endpoint_id = match iroh::EndpointId::from_bytes(&anchor_nid) {
                                Ok(eid) => eid,
                                Err(_) => continue,
                            };
                            let mut addr = iroh::EndpointAddr::from(endpoint_id);
                            for sa in &anchor_addrs {
                                addr = addr.with_ip_addr(*sa);
                            }
                            if let Err(e) = network.connect_to_anchor(anchor_nid, addr).await {
                                tracing::debug!(error = %e, "Anchor cycle: connect failed");
                                continue;
                            }
                        }
                        match network.request_anchor_referrals(&anchor_nid).await {
                            Ok(referrals) => {
                                for referral in referrals {
                                    if referral.node_id == node_id {
                                        continue;
                                    }
                                    if let Some(addr_str) = referral.addresses.first() {
                                        let connect_str = format!(
                                            "{}@{}",
                                            hex::encode(referral.node_id),
                                            addr_str,
                                        );
                                        if let Ok((rid, raddr)) = crate::parse_connect_string(&connect_str) {
                                            match network.connect_to_peer(rid, raddr).await {
                                                Ok(()) => {
                                                    tracing::info!(peer = hex::encode(rid), "Anchor cycle: connected to referred peer");
                                                    log_evt(ActivityLevel::Info, ActivityCategory::Anchor, "Connected to referred peer".into(), Some(rid));
                                                }
                                                Err(_) => {
                                                    match network.connect_via_introduction(rid, anchor_nid).await {
                                                        Ok(()) => {
                                                            tracing::info!(peer = hex::encode(rid), "Anchor cycle: connected via hole punch");
                                                            log_evt(ActivityLevel::Info, ActivityCategory::Anchor, "Connected via hole punch".into(), Some(rid));
                                                        }
                                                        Err(e) => {
                                                            tracing::debug!(error = %e, peer = hex::encode(rid), "Anchor cycle: hole punch failed");
                                                            log_evt(ActivityLevel::Warn, ActivityCategory::Anchor, format!("Hole punch failed: {}", e), Some(rid));
                                                        }
                                                    }
                                                }
                                            }
                                        }
                                    }
                                }
                            }
                            Err(e) => tracing::debug!(error = %e, "Anchor cycle: referral request failed"),
                        }
                    }
                }

                // Anchor self-verification probe
                {
                    let probe_due = network.conn_handle().probe_due().await;
                    if probe_due {
                        log_evt(ActivityLevel::Info, ActivityCategory::Anchor, "Initiating anchor self-verification probe".into(), None);
                        match network.conn_handle().initiate_anchor_probe().await {
                            Ok(true) => {},  // success already logged inside
                            Ok(false) => {}, // failure already logged inside
                            Err(e) => {
                                tracing::debug!(error = %e, "Anchor probe error");
                            }
                        }
                    }
                }
            }
        })
    }

    /// Start bootstrap connectivity check: 24 hours after startup, verify the bootstrap
    /// anchor is within our network knowledge (N1/N2/N3). If not, we may be in an isolated
    /// segment — reconnect to bootstrap and request referrals to bridge back.
    pub fn start_bootstrap_connectivity_check(self: &Arc<Self>) -> tokio::task::JoinHandle<()> {
        let node = Arc::clone(self);
        tokio::spawn(async move {
            // Wait 24 hours before first check
            tokio::time::sleep(std::time::Duration::from_secs(24 * 60 * 60)).await;

            let mut interval = tokio::time::interval(std::time::Duration::from_secs(24 * 60 * 60));
            loop {
                interval.tick().await;

                // Parse bootstrap anchor NodeId
                let bootstrap_nid = match crate::parse_connect_string(DEFAULT_ANCHOR) {
                    Ok((nid, _)) => nid,
                    Err(_) => continue,
                };

                // Skip if we ARE the bootstrap
                if bootstrap_nid == node.node_id {
                    continue;
                }

                // Check if bootstrap is in N1 (mesh), N2, or N3
                let is_reachable = {
                    let connected = node.network.is_connected(&bootstrap_nid).await;
                    if connected {
                        true
                    } else {
                        let storage = node.storage.get().await;
                        let in_n2 = storage.find_in_n2(&bootstrap_nid).unwrap_or_default();
                        if !in_n2.is_empty() {
                            true
                        } else {
                            let in_n3 = storage.find_in_n3(&bootstrap_nid).unwrap_or_default();
                            !in_n3.is_empty()
                        }
                    }
                };

                if is_reachable {
                    tracing::debug!("Bootstrap connectivity check: bootstrap in reach, network OK");
                    continue;
                }

                // Bootstrap not in N1/N2/N3 — we may be isolated
                tracing::info!("Bootstrap connectivity check: bootstrap not in reach, reconnecting");

                // Connect to bootstrap and request referrals
                if let Err(e) = node.connect_by_node_id(bootstrap_nid).await {
                    tracing::warn!(error = %e, "Bootstrap connectivity: failed to connect");
                    continue;
                }

                // Report bootstrap in our N1 for 24 hours so peers learn about it
                node.network.conn_handle().add_sticky_n1(&bootstrap_nid, 24 * 60 * 60 * 1000);

                match node.network.request_anchor_referrals(&bootstrap_nid).await {
                    Ok(referrals) => {
                        tracing::info!(count = referrals.len(), "Bootstrap connectivity: got referrals");
                        for referral in referrals {
                            if referral.node_id == node.node_id { continue; }
                            if let Some(addr_str) = referral.addresses.first() {
                                let connect_str = format!("{}@{}", hex::encode(referral.node_id), addr_str);
                                if let Ok((rid, raddr)) = crate::parse_connect_string(&connect_str) {
                                    let _ = node.network.connect_to_peer(rid, raddr).await;
                                }
                            }
                        }
                    }
                    Err(e) => {
                        tracing::warn!(error = %e, "Bootstrap connectivity: referral request failed");
                    }
                }
            }
        })
    }

    /// Start CDN manifest refresh cycle: periodically ask upstream for newer manifests.
    /// Manifests older than `max_age_ms` are refreshed from their upstream source.
    pub fn start_manifest_refresh_cycle(&self, interval_secs: u64, max_age_ms: u64) -> tokio::task::JoinHandle<()> {
        let network = Arc::clone(&self.network);
        let storage = Arc::clone(&self.storage);
        tokio::spawn(async move {
            let mut interval =
                tokio::time::interval(std::time::Duration::from_secs(interval_secs));
            loop {
                interval.tick().await;
                let cutoff = std::time::SystemTime::now()
                    .duration_since(std::time::UNIX_EPOCH)
                    .unwrap_or_default()
                    .as_millis() as u64 - max_age_ms;
                let stale_cids = {
                    let s = storage.get().await;
                    s.get_stale_manifest_cids(cutoff).unwrap_or_default()
                };
                for cid in &stale_cids {
                    // Get current updated_at + pick a holder to refresh from
                    let (current_updated_at, refresh_source) = {
                        let s = storage.get().await;
                        let updated_at = s.get_cdn_manifest(cid).ok().flatten()
                            .and_then(|json| serde_json::from_str::<crate::types::AuthorManifest>(&json).ok())
                            .map(|m| m.updated_at)
                            .unwrap_or(0);
                        let source = s.get_file_holders(cid)
                            .unwrap_or_default()
                            .into_iter()
                            .next()
                            .map(|(nid, _)| nid);
                        (updated_at, source)
                    };
                    let Some(upstream_nid) = refresh_source else { continue; };
                    match network.request_manifest_refresh(cid, &upstream_nid, current_updated_at).await {
                        Ok(Some(cdn_manifest)) => {
                            if crypto::verify_manifest_signature(&cdn_manifest.author_manifest) {
                                let author_json = serde_json::to_string(&cdn_manifest.author_manifest).unwrap_or_default();
                                let s = storage.get().await;
                                let _ = s.store_cdn_manifest(
                                    cid,
                                    &author_json,
                                    &cdn_manifest.author_manifest.author,
                                    cdn_manifest.author_manifest.updated_at,
                                );
                                // Relay to known holders (flat set)
                                let holders = s.get_file_holders(cid).unwrap_or_default();
                                drop(s);
                                if !holders.is_empty() {
                                    network.push_manifest_to_downstream(cid, &cdn_manifest).await;
                                }
                                tracing::debug!(
                                    cid = hex::encode(cid),
                                    "Refreshed stale manifest from upstream"
                                );
                            }
                        }
                        Ok(None) => {} // No update available
                        Err(e) => {
                            tracing::debug!(
                                cid = hex::encode(cid),
                                upstream = hex::encode(&upstream_nid),
                                error = %e,
                                "Manifest refresh from upstream failed"
                            );
                        }
                    }
                }
            }
        })
    }

    /// Build our N+10:Addresses (our connected peers with their addresses).
    pub async fn build_peer_addresses(&self) -> Vec<PeerWithAddress> {
        let conns = self.network.connection_info().await;
        let storage = self.storage.get().await;
        let mut result = Vec::new();
        for (nid, kind, _) in conns {
            if nid == self.node_id {
                continue;
            }
            // Prefer social peers
            if kind != PeerSlotKind::Local && result.len() >= 10 {
                continue;
            }
            let addrs: Vec<String> = storage.get_peer_record(&nid)
                .ok()
                .flatten()
                .map(|r| r.addresses.iter().map(|a| a.to_string()).collect())
                .unwrap_or_default();
            result.push(PeerWithAddress {
                n: hex::encode(nid),
                a: addrs,
            });
            if result.len() >= 10 {
                break;
            }
        }
        result
    }

    /// List all social routes (for CLI/Tauri display).
    pub async fn list_social_routes(&self) -> anyhow::Result<Vec<SocialRouteEntry>> {
        let storage = self.storage.get().await;
        storage.list_social_routes()
    }

    // ---- Blob Eviction ----

    /// Compute priority score for a blob. Higher score = keep longer.
    pub fn compute_blob_priority(
        &self,
        candidate: &crate::storage::EvictionCandidate,
        follows: &[NodeId],
        now_ms: u64,
    ) -> f64 {
        compute_blob_priority_standalone(candidate, &self.node_id, follows, now_ms)
    }

    /// Delete a blob locally. BlobDeleteNotice was removed in v0.6.2; remote
    /// holders notice eviction via their own LRU / replica-miss handling.
    pub async fn delete_blob_local(&self, cid: &[u8; 32]) -> anyhow::Result<()> {
        {
            let storage = self.storage.get().await;
            storage.cleanup_cdn_for_blob(cid)?;
            storage.remove_blob(cid)?;
        }
        let _ = self.blob_store.delete(cid);

        Ok(())
    }

    /// Evict lowest-priority blobs until total storage is under max_bytes.
    pub async fn evict_blobs(&self, max_bytes: u64) -> anyhow::Result<usize> {
        let total = {
            let storage = self.storage.get().await;
            storage.total_blob_bytes()?
        };

        if total <= max_bytes {
            return Ok(0);
        }

        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        // 1-hour staleness for replica counts
        let staleness_ms = 3600 * 1000;

        let (candidates, follows) = {
            let storage = self.storage.get().await;
            let candidates = storage.get_eviction_candidates(staleness_ms)?;
            let follows = storage.list_follows().unwrap_or_default();
            (candidates, follows)
        };

        // Score and sort ascending (lowest priority first)
        let mut scored: Vec<(f64, &crate::storage::EvictionCandidate)> = candidates
            .iter()
            .map(|c| (self.compute_blob_priority(c, &follows, now), c))
            .collect();
        scored.sort_by(|a, b| a.0.partial_cmp(&b.0).unwrap_or(std::cmp::Ordering::Equal));

        let mut bytes_freed: u64 = 0;
        let target_free = total - max_bytes;
        let mut evicted = 0;

        for (score, candidate) in &scored {
            if bytes_freed >= target_free {
                break;
            }
            if let Err(e) = self.delete_blob_local(&candidate.cid).await {
                warn!(cid = hex::encode(candidate.cid), error = %e, "Failed to evict blob");
                continue;
            }
            bytes_freed += candidate.size_bytes;
            evicted += 1;
            info!(
                cid = hex::encode(candidate.cid),
                score = score,
                size = candidate.size_bytes,
                "Evicted blob"
            );
        }

        info!(evicted, bytes_freed, "Blob eviction complete");
        Ok(evicted)
    }

    /// Start a periodic eviction cycle.
    pub fn start_eviction_cycle(
        node: Arc<Self>,
        interval_secs: u64,
        max_bytes: u64,
    ) -> tokio::task::JoinHandle<()>
    where
        Self: Send + Sync + 'static,
    {
        tokio::spawn(async move {
            let mut interval = tokio::time::interval(std::time::Duration::from_secs(interval_secs));
            loop {
                interval.tick().await;
                match node.evict_blobs(max_bytes).await {
                    Ok(0) => {}
                    Ok(n) => info!(evicted = n, "Eviction cycle complete"),
                    Err(e) => warn!(error = %e, "Eviction cycle failed"),
                }
            }
        })
    }

    /// Start UPnP lease renewal cycle. Renews every lease_secs/2.
    /// On 3 consecutive failures: clears is_anchor and logs a warning.
    pub fn start_upnp_renewal_cycle(&self) -> Option<tokio::task::JoinHandle<()>> {
        let mapping = self.network.upnp_mapping()?;
        let local_port = mapping.local_port;
        let external_port = mapping.external_addr.port();
        let interval_secs = (mapping.lease_secs / 2) as u64;
        let network = Arc::clone(&self.network);
        let alog = Arc::clone(&self.activity_log);

        Some(tokio::spawn(async move {
            let mut interval =
                tokio::time::interval(std::time::Duration::from_secs(interval_secs));
            let mut consecutive_failures: u32 = 0;
            loop {
                interval.tick().await;
                if crate::upnp::renew_upnp_mapping(local_port, external_port).await {
                    consecutive_failures = 0;
                    debug!("UPnP: lease renewed (port {})", external_port);
                } else {
                    consecutive_failures += 1;
                    warn!("UPnP: renewal failed ({}/3)", consecutive_failures);
                    if consecutive_failures >= 3 {
                        network.clear_anchor();
                        if let Ok(mut log) = alog.try_lock() {
                            log.log(
                                ActivityLevel::Warn,
                                ActivityCategory::Connection,
                                "UPnP lease lost after 3 renewal failures, auto-anchor disabled".into(),
                                None,
                            );
                        }
                        warn!("UPnP: 3 consecutive renewal failures, auto-anchor disabled");
                        return; // stop the cycle
                    }
                }
            }
        }))
    }

    // --- HTTP Post Delivery ---

    /// Start the HTTP server for serving public posts to browsers.
    /// Only starts if this node is publicly TCP-reachable.
    pub fn start_http_server(&self) -> Option<tokio::task::JoinHandle<()>> {
        if !self.network.is_http_capable() {
            debug!("HTTP server not started: node is not publicly TCP-reachable");
            return None;
        }
        let port = self.network.bound_port();
        if port == 0 {
            return None;
        }
        let storage = Arc::clone(&self.storage);
        let blob_store = Arc::clone(&self.blob_store);
        let downstream_addrs = Arc::new(tokio::sync::Mutex::new(
            std::collections::HashMap::<[u8; 32], Vec<std::net::SocketAddr>>::new(),
        ));

        // Advertise HTTP capability to peers
        let http_addr = self.network.http_addr();
        self.network.conn_handle().set_http_info(true, http_addr.clone());
        // Also update the ConnectionManager's fields for payload construction
        {
            let rt = tokio::runtime::Handle::current();
            let conn_mgr = Arc::clone(&self.network.conn_mgr_arc());
            rt.spawn(async move {
                let mut cm = conn_mgr.lock().await;
                cm.http_capable = true;
                cm.http_addr = http_addr;
            });
        }

        info!("Starting HTTP server on TCP port {}", port);
        Some(tokio::spawn(async move {
            if let Err(e) = crate::http::run_http_server(port, storage, blob_store, downstream_addrs).await {
                warn!("HTTP server stopped: {}", e);
            }
        }))
    }

    /// Start the web redirect handler (itsgoin.net share link resolution).
    pub fn start_web_handler(self: &Arc<Self>, port: u16) -> tokio::task::JoinHandle<()> {
        let node = Arc::clone(self);
        info!("Starting web redirect handler on port {}", port);
        tokio::spawn(async move {
            if let Err(e) = crate::web::run_web_handler(port, node).await {
                warn!("Web redirect handler stopped: {}", e);
            }
        })
    }

    /// Start UPnP TCP lease renewal cycle alongside the UDP renewal.
    pub fn start_upnp_tcp_renewal_cycle(&self) -> Option<tokio::task::JoinHandle<()>> {
        if !self.network.has_upnp_tcp() {
            return None;
        }
        let mapping = self.network.upnp_mapping()?;
        let local_port = mapping.local_port;
        let external_port = mapping.external_addr.port();
        let interval_secs = (mapping.lease_secs / 2) as u64;

        Some(tokio::spawn(async move {
            let mut interval =
                tokio::time::interval(std::time::Duration::from_secs(interval_secs));
            loop {
                interval.tick().await;
                if !crate::upnp::renew_upnp_tcp_mapping(local_port, external_port).await {
                    warn!("UPnP: TCP lease renewal failed");
                    // Don't stop the cycle — TCP is best-effort
                }
            }
        }))
    }

    /// Generate a share link URL for a public post.
    /// Returns None if post is not public or not found.
    pub async fn generate_share_link(&self, post_id: &PostId) -> anyhow::Result<Option<String>> {
        // Look up the post to verify it's public and get the author
        let (post, visibility) = {
            let store = self.storage.get().await;
            match store.get_post_with_visibility(post_id)? {
                Some(pv) => pv,
                None => return Ok(None),
            }
        };

        if !matches!(visibility, PostVisibility::Public) {
            return Ok(None);
        }

        let post_hex = hex::encode(post_id);
        let author_hex = hex::encode(post.author);
        Ok(Some(format!("https://itsgoin.net/p/{}/{}", post_hex, author_hex)))
    }

    // --- Engagement API ---

    /// React to a post with an emoji. If `private`, encrypts payload for post author only.
    pub async fn react_to_post(
        &self,
        post_id: PostId,
        emoji: String,
        private: bool,
    ) -> anyhow::Result<crate::types::Reaction> {
        let our_node_id = self.default_posting_id;
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        // For private reactions, look up the post author and encrypt
        let encrypted_payload = if private {
            let storage = self.storage.get().await;
            let post = storage.get_post(&post_id)?
                .ok_or_else(|| anyhow::anyhow!("post not found"))?;
            drop(storage);
            let seed = self.default_posting_secret;
            let payload_json = serde_json::json!({
                "emoji": emoji,
                "reactor": hex::encode(our_node_id),
                "timestamp_ms": now,
            }).to_string();
            Some(crate::crypto::encrypt_private_reaction(&seed, &post.author, &payload_json)?)
        } else {
            None
        };

        let signature = crate::crypto::sign_reaction(&self.default_posting_secret, &our_node_id, &post_id, &emoji, now);
        let reaction = crate::types::Reaction {
            reactor: our_node_id,
            emoji: emoji.clone(),
            post_id,
            timestamp_ms: now,
            encrypted_payload,
            deleted_at: None,
            signature,
        };

        // Store locally
        let storage = self.storage.get().await;
        storage.store_reaction(&reaction)?;
        drop(storage);

        // Propagate via BlobHeaderDiff to downstream + upstream
        {
            let network = &self.network;
            let diff = crate::protocol::BlobHeaderDiffPayload {
                post_id,
                author: our_node_id,
                ops: vec![crate::types::BlobHeaderDiffOp::AddReaction(reaction.clone())],
                timestamp_ms: now,
            };
            // propagate_engagement_diff targets all file_holders (flat set, max 5)
            // which already subsumes what used to be upstream + downstream.
            network.propagate_engagement_diff(&post_id, &diff, &our_node_id).await;
        }

        Ok(reaction)
    }

    /// Remove a reaction from a post.
    pub async fn remove_reaction(&self, post_id: PostId, emoji: String) -> anyhow::Result<()> {
        let our_node_id = self.default_posting_id;
        let storage = self.storage.get().await;
        storage.remove_reaction(&our_node_id, &post_id, &emoji)?;
        drop(storage);

        // Propagate removal
        {
            let network = &self.network;
            let now = std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)?
                .as_millis() as u64;
            let diff = crate::protocol::BlobHeaderDiffPayload {
                post_id,
                author: our_node_id,
                ops: vec![crate::types::BlobHeaderDiffOp::RemoveReaction {
                    reactor: our_node_id,
                    emoji,
                    post_id,
                }],
                timestamp_ms: now,
            };
            network.propagate_engagement_diff(&post_id, &diff, &our_node_id).await;
        }

        Ok(())
    }

    /// Get all reactions for a post. Decrypts private reactions if we're the post author.
    pub async fn get_reactions(&self, post_id: PostId) -> anyhow::Result<Vec<crate::types::Reaction>> {
        let storage = self.storage.get().await;
        let reactions = storage.get_reactions(&post_id)?;
        let post_info = storage.get_post(&post_id)?;
        drop(storage);

        let our_node_id = self.default_posting_id;

        // If we're the author, decrypt private reactions
        if let Some(post) = post_info {
            if post.author == our_node_id {
                let seed = self.default_posting_secret;
                return Ok(reactions.into_iter().map(|mut r| {
                    if let Some(ref enc) = r.encrypted_payload {
                        if let Ok(decrypted) = crate::crypto::decrypt_private_reaction(&seed, &r.reactor, enc) {
                            r.encrypted_payload = Some(decrypted);
                        }
                    }
                    r
                }).collect());
            }
        }

        Ok(reactions)
    }

    /// Get reaction counts grouped by emoji for a post.
    pub async fn get_reaction_counts(&self, post_id: PostId) -> anyhow::Result<Vec<(String, u64, bool)>> {
        let our_node_id = self.default_posting_id;
        let storage = self.storage.get().await;
        let counts = storage.get_reaction_counts(&post_id, &our_node_id)?;
        Ok(counts)
    }

    /// Add a plain inline comment to a post (signed with our posting key).
    /// The comment's `content` is the full text; `ref_post_id` is None.
    pub async fn comment_on_post(
        &self,
        post_id: PostId,
        content: String,
    ) -> anyhow::Result<crate::types::InlineComment> {
        self.comment_on_post_inner(post_id, content, None).await
    }

    /// Add a rich comment: the full body lives in `ref_post_id` (typically a
    /// newly-created public post by the commenter that carries attachments
    /// or a long body). The inline `preview` text appears in the parent
    /// post's header-diff and is what most clients render by default; the
    /// expanded view fetches the referenced post. Signature binds the
    /// preview + ref_post_id so a peer can't rewrite either independently.
    pub async fn comment_on_post_with_ref(
        &self,
        post_id: PostId,
        preview: String,
        ref_post_id: PostId,
    ) -> anyhow::Result<crate::types::InlineComment> {
        self.comment_on_post_inner(post_id, preview, Some(ref_post_id)).await
    }

    async fn comment_on_post_inner(
        &self,
        post_id: PostId,
        content: String,
        ref_post_id: Option<PostId>,
    ) -> anyhow::Result<crate::types::InlineComment> {
        let our_node_id = self.default_posting_id;
        let seed = self.default_posting_secret;
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        let signature = crate::crypto::sign_comment(
            &seed,
            &our_node_id,
            &post_id,
            &content,
            now,
            ref_post_id.as_ref(),
        );

        let comment = crate::types::InlineComment {
            author: our_node_id,
            post_id,
            content,
            timestamp_ms: now,
            signature,
            deleted_at: None,
            ref_post_id,
        };

        let storage = self.storage.get().await;
        storage.store_comment(&comment)?;
        drop(storage);

        // Propagate via BlobHeaderDiff to the target post's known holders.
        {
            let network = &self.network;
            let diff = crate::protocol::BlobHeaderDiffPayload {
                post_id,
                author: our_node_id,
                ops: vec![crate::types::BlobHeaderDiffOp::AddComment(comment.clone())],
                timestamp_ms: now,
            };
            network.propagate_engagement_diff(&post_id, &diff, &our_node_id).await;
        }

        Ok(comment)
    }

    /// Edit one of your own comments on a post.
    pub async fn edit_comment(
        &self,
        post_id: PostId,
        timestamp_ms: u64,
        new_content: String,
    ) -> anyhow::Result<()> {
        let our_node_id = self.default_posting_id;
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        let storage = self.storage.get().await;
        storage.edit_comment(&our_node_id, &post_id, timestamp_ms, &new_content)?;
        drop(storage);

        // Propagate via BlobHeaderDiff
        {
            let network = &self.network;
            let diff = crate::protocol::BlobHeaderDiffPayload {
                post_id,
                author: our_node_id,
                ops: vec![crate::types::BlobHeaderDiffOp::EditComment {
                    author: our_node_id,
                    post_id,
                    timestamp_ms,
                    new_content,
                }],
                timestamp_ms: now,
            };
            network.propagate_engagement_diff(&post_id, &diff, &our_node_id).await;
        }
        Ok(())
    }

    /// Delete one of your own comments on a post.
    pub async fn delete_comment(
        &self,
        post_id: PostId,
        timestamp_ms: u64,
    ) -> anyhow::Result<()> {
        let our_node_id = self.default_posting_id;
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        let storage = self.storage.get().await;
        storage.delete_comment(&our_node_id, &post_id, timestamp_ms)?;
        drop(storage);

        // Propagate via BlobHeaderDiff
        {
            let network = &self.network;
            let diff = crate::protocol::BlobHeaderDiffPayload {
                post_id,
                author: our_node_id,
                ops: vec![crate::types::BlobHeaderDiffOp::DeleteComment {
                    author: our_node_id,
                    post_id,
                    timestamp_ms,
                }],
                timestamp_ms: now,
            };
            network.propagate_engagement_diff(&post_id, &diff, &our_node_id).await;
        }
        Ok(())
    }

    /// Get all comments for a post.
    pub async fn get_comments(&self, post_id: PostId) -> anyhow::Result<Vec<crate::types::InlineComment>> {
        let storage = self.storage.get().await;
        let comments = storage.get_comments(&post_id)?;
        Ok(comments)
    }

    /// Set the comment/reaction policy for a post (author-only).
    pub async fn set_comment_policy(
        &self,
        post_id: PostId,
        policy: crate::types::CommentPolicy,
    ) -> anyhow::Result<()> {
        let storage = self.storage.get().await;
        storage.set_comment_policy(&post_id, &policy)?;
        drop(storage);

        // Propagate policy change
        {
            let network = &self.network;
            let our_node_id = self.default_posting_id;
            let now = std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)?
                .as_millis() as u64;
            let diff = crate::protocol::BlobHeaderDiffPayload {
                post_id,
                author: our_node_id,
                ops: vec![crate::types::BlobHeaderDiffOp::SetPolicy(policy)],
                timestamp_ms: now,
            };
            network.propagate_engagement_diff(&post_id, &diff, &our_node_id).await;
        }

        Ok(())
    }

    /// Get the comment policy for a post.
    pub async fn get_comment_policy(&self, post_id: PostId) -> anyhow::Result<Option<crate::types::CommentPolicy>> {
        let storage = self.storage.get().await;
        let policy = storage.get_comment_policy(&post_id)?;
        Ok(policy)
    }

    /// Get the full comment thread for a post (inline comments + split posts merged).
    pub async fn get_comment_thread(&self, post_id: PostId) -> anyhow::Result<Vec<crate::types::InlineComment>> {
        let storage = self.storage.get().await;

        // 1. Inline comments
        let mut comments = storage.get_comments(&post_id)?;

        // 2. Split posts (thread children)
        let children = storage.get_thread_children(&post_id)?;
        for child_id in children {
            if let Ok(Some(child_post)) = storage.get_post(&child_id) {
                // Split posts store comments as JSON in content
                if let Ok(split_comments) = serde_json::from_str::<Vec<crate::types::InlineComment>>(&child_post.content) {
                    comments.extend(split_comments);
                }
            }
        }

        // Dedup by (author, timestamp_ms) and sort
        let mut seen = std::collections::HashSet::new();
        comments.retain(|c| seen.insert((c.author, c.timestamp_ms)));
        comments.sort_by_key(|c| c.timestamp_ms);

        Ok(comments)
    }

    // --- Encrypted receipt/comment slot methods ---

    /// Unwrap the CEK for a post we are a participant of, returning (cek, sorted_participants).
    /// Returns None if this is a public post or we cannot decrypt.
    async fn get_post_cek_and_participants(
        &self,
        post_id: &PostId,
    ) -> anyhow::Result<Option<([u8; 32], Vec<NodeId>)>> {
        let storage = self.storage.get().await;
        let (post, visibility) = match storage.get_post_with_visibility(post_id)? {
            Some(pv) => pv,
            None => return Ok(None),
        };
        drop(storage);

        match &visibility {
            PostVisibility::Public => Ok(None),
            PostVisibility::Encrypted { recipients } => {
                let cek = crypto::unwrap_cek_for_recipient(
                    &self.default_posting_secret,
                    &self.node_id,
                    &post.author,
                    recipients,
                )?;
                match cek {
                    Some(cek) => {
                        let mut participants: Vec<NodeId> = recipients.iter().map(|wk| wk.recipient).collect();
                        participants.sort();
                        participants.dedup();
                        Ok(Some((cek, participants)))
                    }
                    None => Ok(None),
                }
            }
            PostVisibility::GroupEncrypted { group_id, epoch, wrapped_cek } => {
                let storage = self.storage.get().await;
                let group_seeds = storage.get_all_group_seeds_map().unwrap_or_default();
                let group_key_record = storage.get_group_key(group_id)?;
                let members = if let Some(ref gk) = group_key_record {
                    storage.get_circle_members(&gk.circle_name).unwrap_or_default()
                } else {
                    vec![]
                };
                drop(storage);

                if let Some((seed, pubkey)) = group_seeds.get(&(*group_id, *epoch)) {
                    let cek = crypto::unwrap_group_cek(seed, pubkey, wrapped_cek)?;
                    let mut participants: Vec<NodeId> = members;
                    // Ensure the author is included
                    if !participants.contains(&post.author) {
                        participants.push(post.author);
                    }
                    participants.sort();
                    participants.dedup();
                    Ok(Some((cek, participants)))
                } else {
                    Ok(None)
                }
            }
        }
    }

    /// Write our receipt slot for an encrypted post.
    /// `state` is the receipt state, `emoji` is optional (only used when state == Reacted).
    pub async fn write_receipt_slot(
        &self,
        post_id: PostId,
        state: crate::types::ReceiptState,
        emoji: Option<String>,
    ) -> anyhow::Result<()> {
        let (cek, participants) = self.get_post_cek_and_participants(&post_id).await?
            .ok_or_else(|| anyhow::anyhow!("not a participant of this encrypted post"))?;
        let slot_key = crypto::derive_slot_key(&cek);

        // Find our slot index (sorted participant position)
        let our_slot = participants.iter().position(|nid| nid == &self.node_id)
            .ok_or_else(|| anyhow::anyhow!("our node_id not found in participants"))?;

        // Build plaintext: [1 byte state][8 bytes timestamp_ms][23 bytes emoji+padding]
        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;
        let mut plaintext = [0u8; 32];
        plaintext[0] = state as u8;
        plaintext[1..9].copy_from_slice(&now.to_le_bytes());
        if let Some(ref emoji_str) = emoji {
            let emoji_bytes = emoji_str.as_bytes();
            let copy_len = emoji_bytes.len().min(23);
            plaintext[9..9 + copy_len].copy_from_slice(&emoji_bytes[..copy_len]);
        }

        let encrypted = crypto::encrypt_slot(&plaintext, &slot_key)?;

        // Update the BlobHeader
        let storage = self.storage.get().await;
        let header = storage.get_blob_header(&post_id)?;
        let mut blob_header = if let Some((json, _ts)) = header {
            serde_json::from_str::<crate::types::BlobHeader>(&json)
                .unwrap_or_else(|_| crate::types::BlobHeader {
                    post_id,
                    author: self.default_posting_id,
                    reactions: vec![],
                    comments: vec![],
                    policy: Default::default(),
                    updated_at: now,
                    thread_splits: vec![],
                    receipt_slots: vec![],
                    comment_slots: vec![],
                    prior_author: None,
                })
        } else {
            crate::types::BlobHeader {
                post_id,
                author: self.default_posting_id,
                reactions: vec![],
                comments: vec![],
                policy: Default::default(),
                updated_at: now,
                thread_splits: vec![],
                receipt_slots: vec![],
                comment_slots: vec![],
                prior_author: None,
            }
        };

        // Ensure enough slots exist
        while blob_header.receipt_slots.len() <= our_slot {
            blob_header.receipt_slots.push(crypto::random_slot_noise(64));
        }
        blob_header.receipt_slots[our_slot] = encrypted.clone();
        blob_header.updated_at = now;

        let header_json = serde_json::to_string(&blob_header)?;
        storage.store_blob_header(&post_id, &blob_header.author, &header_json, now)?;
        drop(storage);

        // Propagate via BlobHeaderDiff
        let diff = crate::protocol::BlobHeaderDiffPayload {
            post_id,
            author: self.default_posting_id,
            ops: vec![crate::types::BlobHeaderDiffOp::WriteReceiptSlot {
                post_id,
                slot_index: our_slot as u32,
                data: encrypted,
            }],
            timestamp_ms: now,
        };
        self.network.propagate_engagement_diff(&post_id, &diff, &self.node_id).await;

        Ok(())
    }

    /// Write a private comment to an encrypted post's comment slot.
    pub async fn write_comment_slot(
        &self,
        post_id: PostId,
        content: String,
    ) -> anyhow::Result<()> {
        let (cek, _participants) = self.get_post_cek_and_participants(&post_id).await?
            .ok_or_else(|| anyhow::anyhow!("not a participant of this encrypted post"))?;
        let slot_key = crypto::derive_slot_key(&cek);

        let now = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_millis() as u64;

        // Build plaintext: [32 bytes author_node_id][8 bytes timestamp_ms][216 bytes content+padding]
        let mut plaintext = [0u8; 256];
        plaintext[..32].copy_from_slice(&self.node_id);
        plaintext[32..40].copy_from_slice(&now.to_le_bytes());
        let content_bytes = content.as_bytes();
        let copy_len = content_bytes.len().min(216);
        plaintext[40..40 + copy_len].copy_from_slice(&content_bytes[..copy_len]);

        let encrypted = crypto::encrypt_slot(&plaintext, &slot_key)?;

        // Find first available comment slot or add new ones
        let storage = self.storage.get().await;
        let header = storage.get_blob_header(&post_id)?;
        let mut blob_header = if let Some((json, _ts)) = header {
            serde_json::from_str::<crate::types::BlobHeader>(&json)
                .unwrap_or_else(|_| crate::types::BlobHeader {
                    post_id,
                    author: self.default_posting_id,
                    reactions: vec![],
                    comments: vec![],
                    policy: Default::default(),
                    updated_at: now,
                    thread_splits: vec![],
                    receipt_slots: vec![],
                    comment_slots: vec![],
                    prior_author: None,
                })
        } else {
            crate::types::BlobHeader {
                post_id,
                author: self.default_posting_id,
                reactions: vec![],
                comments: vec![],
                policy: Default::default(),
                updated_at: now,
                thread_splits: vec![],
                receipt_slots: vec![],
                comment_slots: vec![],
                prior_author: None,
            }
        };

        // Try to find an empty slot by attempting decryption
        let mut target_index = None;
        for (i, slot) in blob_header.comment_slots.iter().enumerate() {
            if let Ok(decrypted) = crypto::decrypt_slot(slot, &slot_key) {
                // Check if all 256 plaintext bytes are zero (empty)
                if decrypted.len() == 256 && decrypted.iter().all(|&b| b == 0) {
                    target_index = Some(i);
                    break;
                }
            } else {
                // Cannot decrypt — could be random noise (empty), use it
                target_index = Some(i);
                break;
            }
        }

        let (slot_index, add_new) = if let Some(idx) = target_index {
            (idx, false)
        } else {
            // No available slots — add one
            let idx = blob_header.comment_slots.len();
            blob_header.comment_slots.push(crypto::random_slot_noise(256));
            (idx, true)
        };

        blob_header.comment_slots[slot_index] = encrypted.clone();
        blob_header.updated_at = now;

        let header_json = serde_json::to_string(&blob_header)?;
        storage.store_blob_header(&post_id, &blob_header.author, &header_json, now)?;
        drop(storage);

        // Propagate
        let op = if add_new {
            crate::types::BlobHeaderDiffOp::AddCommentSlots {
                post_id,
                count: 1,
                slots: vec![encrypted],
            }
        } else {
            crate::types::BlobHeaderDiffOp::WriteCommentSlot {
                post_id,
                slot_index: slot_index as u32,
                data: encrypted,
            }
        };

        let diff = crate::protocol::BlobHeaderDiffPayload {
            post_id,
            author: self.default_posting_id,
            ops: vec![op],
            timestamp_ms: now,
        };
        self.network.propagate_engagement_diff(&post_id, &diff, &self.node_id).await;

        Ok(())
    }

    /// Read and decrypt all receipt slots for an encrypted post.
    pub async fn read_receipt_slots(
        &self,
        post_id: PostId,
    ) -> anyhow::Result<Vec<crate::types::ReceiptSlotData>> {
        let (cek, participants) = self.get_post_cek_and_participants(&post_id).await?
            .ok_or_else(|| anyhow::anyhow!("not a participant of this encrypted post"))?;
        let slot_key = crypto::derive_slot_key(&cek);

        let storage = self.storage.get().await;
        let header = storage.get_blob_header(&post_id)?;
        drop(storage);

        let blob_header = match header {
            Some((json, _ts)) => serde_json::from_str::<crate::types::BlobHeader>(&json)?,
            None => return Ok(vec![]),
        };

        let mut results = Vec::new();
        for (i, slot) in blob_header.receipt_slots.iter().enumerate() {
            let participant_id = participants.get(i).copied();
            match crypto::decrypt_slot(slot, &slot_key) {
                Ok(plaintext) if plaintext.len() >= 9 => {
                    let state = crate::types::ReceiptState::from_u8(plaintext[0]);
                    let timestamp_ms = u64::from_le_bytes(
                        plaintext[1..9].try_into().unwrap_or([0u8; 8]),
                    );
                    let emoji = if state == crate::types::ReceiptState::Reacted && plaintext.len() >= 32 {
                        let emoji_bytes = &plaintext[9..32];
                        let end = emoji_bytes.iter().position(|&b| b == 0).unwrap_or(23);
                        if end > 0 {
                            String::from_utf8(emoji_bytes[..end].to_vec()).ok()
                        } else {
                            None
                        }
                    } else {
                        None
                    };
                    results.push(crate::types::ReceiptSlotData {
                        slot_index: i as u32,
                        node_id: participant_id,
                        state,
                        timestamp_ms,
                        emoji,
                    });
                }
                _ => {
                    // Could not decrypt — noise/uninitialized slot
                    results.push(crate::types::ReceiptSlotData {
                        slot_index: i as u32,
                        node_id: participant_id,
                        state: crate::types::ReceiptState::Empty,
                        timestamp_ms: 0,
                        emoji: None,
                    });
                }
            }
        }

        Ok(results)
    }

    /// Read and decrypt all comment slots for an encrypted post.
    pub async fn read_comment_slots(
        &self,
        post_id: PostId,
    ) -> anyhow::Result<Vec<crate::types::CommentSlotData>> {
        let (cek, _participants) = self.get_post_cek_and_participants(&post_id).await?
            .ok_or_else(|| anyhow::anyhow!("not a participant of this encrypted post"))?;
        let slot_key = crypto::derive_slot_key(&cek);

        let storage = self.storage.get().await;
        let header = storage.get_blob_header(&post_id)?;
        drop(storage);

        let blob_header = match header {
            Some((json, _ts)) => serde_json::from_str::<crate::types::BlobHeader>(&json)?,
            None => return Ok(vec![]),
        };

        let mut results = Vec::new();
        for (i, slot) in blob_header.comment_slots.iter().enumerate() {
            match crypto::decrypt_slot(slot, &slot_key) {
                Ok(plaintext) if plaintext.len() >= 40 => {
                    // Check if it's an empty slot (all zeros)
                    if plaintext.iter().all(|&b| b == 0) {
                        continue;
                    }
                    let mut author = [0u8; 32];
                    author.copy_from_slice(&plaintext[..32]);
                    // Skip if author is all zeros (empty)
                    if author == [0u8; 32] {
                        continue;
                    }
                    let timestamp_ms = u64::from_le_bytes(
                        plaintext[32..40].try_into().unwrap_or([0u8; 8]),
                    );
                    let content_bytes = &plaintext[40..];
                    let end = content_bytes.iter().position(|&b| b == 0).unwrap_or(content_bytes.len());
                    let content = String::from_utf8_lossy(&content_bytes[..end]).to_string();

                    results.push(crate::types::CommentSlotData {
                        slot_index: i as u32,
                        author,
                        timestamp_ms,
                        content,
                    });
                }
                _ => {
                    // Cannot decrypt or too short — skip
                }
            }
        }

        results.sort_by_key(|c| c.timestamp_ms);
        Ok(results)
    }
}

pub struct NodeStats {
    pub post_count: usize,
    pub peer_count: usize,
    pub follow_count: usize,
}

/// Standalone priority scoring for testing.
/// score = pin_boost + (relationship × heart_recency × freshness / (peer_copies + 1))
pub fn compute_blob_priority_standalone(
    candidate: &crate::storage::EvictionCandidate,
    our_node_id: &NodeId,
    follows: &[NodeId],
    now_ms: u64,
) -> f64 {
    let pin_boost = if candidate.pinned { 1000.0 } else { 0.0 };

    // Share-link popularity boost: high downstream count indicates the blob
    // has been shared via share links and is actively being served to others.
    let share_boost = if candidate.downstream_count >= 3 {
        100.0
    } else if candidate.downstream_count >= 1 {
        50.0 * candidate.downstream_count as f64 / 3.0
    } else {
        0.0
    };

    // v0.6.2: audience removed. Relationship is author-of-ours vs followed vs other.
    let relationship = if candidate.author == *our_node_id {
        5.0
    } else if follows.contains(&candidate.author) {
        2.0
    } else {
        0.1
    };

    let thirty_days_ms = 30u64 * 24 * 3600 * 1000;
    let access_age_ms = now_ms.saturating_sub(candidate.last_accessed_at);
    let heart_recency = (1.0 - (access_age_ms as f64 / thirty_days_ms as f64)).max(0.0);

    let post_age_days = now_ms.saturating_sub(candidate.created_at) as f64 / (24.0 * 3600.0 * 1000.0);
    let freshness = 1.0 / (1.0 + post_age_days);

    let copies_factor = 1.0 / (candidate.peer_copies as f64 + 1.0);

    pin_boost + share_boost + (relationship * heart_recency * freshness * copies_factor)
}

// --- Active Replication Cycle ---

impl Node {
    /// Start the active replication cycle: periodically ask peers to hold our
    /// under-replicated recent content. Only Available/Persistent devices initiate.
    pub fn start_replication_cycle(self: &Arc<Self>, interval_secs: u64) -> tokio::task::JoinHandle<()> {
        let node = Arc::clone(self);
        tokio::spawn(async move {
            // Wait 2 minutes before first cycle (let connections establish)
            tokio::time::sleep(std::time::Duration::from_secs(120)).await;
            let mut interval = tokio::time::interval(std::time::Duration::from_secs(interval_secs));
            loop {
                interval.tick().await;
                node.run_replication_check().await;
            }
        })
    }

    /// Single replication check iteration.
    async fn run_replication_check(&self) {
        // All devices initiate replication — phones need their content replicated
        // before they go to sleep.

        // 1. Get own posts < 72h old
        let seventy_two_hours_ms = 72u64 * 3600 * 1000;
        let now_ms = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)
            .unwrap_or_default()
            .as_millis() as u64;
        let since_ms = now_ms.saturating_sub(seventy_two_hours_ms);

        // Get connected peers first (no storage lock needed)
        let connected = self.network.connected_peers().await;
        if connected.is_empty() {
            debug!("No peers for replication");
            return;
        }

        // Priority: Available (desktops) > Persistent (anchors) > Intermittent (phones)
        let role_priority = |role: &DeviceRole| -> u16 {
            match role {
                DeviceRole::Available => 300,   // desktops — best replication targets
                DeviceRole::Persistent => 200,  // anchors — good but save for web
                DeviceRole::Intermittent => 100, // phones — last resort but still useful
            }
        };

        // Single lock: get under-replicated posts AND peer roles/pressure
        let (under_replicated, suitable_peers) = {
            let storage = self.storage.get().await;
            let recent_ids = match storage.get_own_recent_post_ids(&self.node_id, since_ms) {
                Ok(ids) => ids,
                Err(e) => {
                    debug!(error = %e, "Replication: failed to get own recent posts");
                    return;
                }
            };

            // Filter to under-replicated (< 2 holders)
            let mut needs_replication = Vec::new();
            for pid in &recent_ids {
                match storage.get_file_holder_count(pid) {
                    Ok(count) if count < 2 => {
                        needs_replication.push(*pid);
                    }
                    _ => {}
                }
            }

            // Get peer roles + cache pressure in same lock
            let mut candidates = Vec::new();
            for peer_id in &connected {
                if *peer_id == self.node_id { continue; }
                let role_str = storage.get_peer_device_role(peer_id)
                    .ok()
                    .flatten()
                    .unwrap_or_default();
                let role = DeviceRole::from_str_label(&role_str);
                let pressure = storage.get_peer_cache_pressure(peer_id)
                    .ok()
                    .flatten()
                    .unwrap_or(128) as u16;
                // Combined score: role priority + cache pressure
                let score = role_priority(&role) + pressure;
                candidates.push((*peer_id, score));
            }

            (needs_replication, candidates)
        };

        // If none need replication, skip silently
        if under_replicated.is_empty() {
            return;
        }

        if suitable_peers.is_empty() {
            debug!("No peers available for replication");
            return;
        }

        // Pick best candidate (highest combined score)
        let best_peer = suitable_peers
            .iter()
            .max_by_key(|(_, score)| *score)
            .map(|(id, _)| *id)
            .unwrap();

        // 7. Cap at 20 post IDs per request, one request per cycle
        let batch: Vec<PostId> = under_replicated.into_iter().take(20).collect();
        let batch_len = batch.len();

        // 8. Send ReplicationRequest
        match self.network.send_replication_request(&best_peer, batch, 128).await {
            Ok(accepted) => {
                if accepted.is_empty() {
                    debug!(
                        peer = hex::encode(best_peer),
                        "Replication: peer rejected all posts"
                    );
                } else {
                    debug!(
                        peer = hex::encode(best_peer),
                        accepted = accepted.len(),
                        requested = batch_len,
                        "Replication: peer accepted posts"
                    );
                }
            }
            Err(e) => {
                debug!(
                    peer = hex::encode(best_peer),
                    error = %e,
                    "Replication: request failed"
                );
            }
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::storage::EvictionCandidate;

    fn make_node_id(byte: u8) -> NodeId {
        [byte; 32]
    }

    fn make_candidate(
        author: NodeId,
        pinned: bool,
        created_at: u64,
        last_accessed_at: u64,
        peer_copies: u32,
    ) -> EvictionCandidate {
        EvictionCandidate {
            cid: [0u8; 32],
            post_id: [0u8; 32],
            author,
            size_bytes: 1000,
            created_at,
            last_accessed_at,
            pinned,
            peer_copies,
            downstream_count: 0,
        }
    }

    #[test]
    fn own_pinned_scores_highest() {
        let our_id = make_node_id(1);
        let now = 10_000_000_000u64; // ~115 days in ms
        let candidate = make_candidate(our_id, true, now - 86400_000, now, 0);

        let score = compute_blob_priority_standalone(
            &candidate, &our_id, &[], now,
        );
        assert!(score > 1000.0, "own pinned should score >1000, got {}", score);
    }

    #[test]
    fn follow_recent_scores_higher_than_stranger_stale() {
        let our_id = make_node_id(1);
        let follow_id = make_node_id(2);
        let stranger_id = make_node_id(3);
        let now = 10_000_000_000u64;

        let follow_candidate = make_candidate(follow_id, false, now - 86400_000, now, 0);
        let follow_score = compute_blob_priority_standalone(
            &follow_candidate, &our_id, &[follow_id], now,
        );

        let stranger_candidate = make_candidate(
            stranger_id, false,
            now - 10 * 86400_000,
            now - 20 * 86400_000,
            5,
        );
        let stranger_score = compute_blob_priority_standalone(
            &stranger_candidate, &our_id, &[], now,
        );

        assert!(follow_score > stranger_score,
            "follow recent ({}) should score higher than stranger stale ({})",
            follow_score, stranger_score);
    }

    #[test]
    fn no_relationship_scores_near_zero() {
        let our_id = make_node_id(1);
        let stranger = make_node_id(99);
        let now = 10_000_000_000u64;

        let candidate = make_candidate(
            stranger, false,
            now - 30 * 86400_000,
            now - 30 * 86400_000,
            10,
        );
        let score = compute_blob_priority_standalone(
            &candidate, &our_id, &[], now,
        );

        assert!(score < 0.01, "stranger stale should score near 0, got {}", score);
    }

    #[test]
    fn priority_ordering() {
        let our_id = make_node_id(1);
        let follow_id = make_node_id(2);
        let stranger_id = make_node_id(4);
        let now = 10_000_000_000u64;

        let own = make_candidate(our_id, true, now - 86400_000, now, 0);
        let follow = make_candidate(follow_id, false, now - 86400_000, now, 0);
        let stranger = make_candidate(stranger_id, false, now - 30 * 86400_000, now - 30 * 86400_000, 10);

        let own_score = compute_blob_priority_standalone(&own, &our_id, &[follow_id], now);
        let follow_score = compute_blob_priority_standalone(&follow, &our_id, &[follow_id], now);
        let stranger_score = compute_blob_priority_standalone(&stranger, &our_id, &[follow_id], now);

        assert!(own_score > follow_score, "own ({}) > follow ({})", own_score, follow_score);
        assert!(follow_score > stranger_score, "follow ({}) > stranger ({})", follow_score, stranger_score);
    }
}