Added FED devices

Cargo.lock

@@ -617,9 +617,9 @@ checksum = "fc652a48c352aef3ea3aed32080501cf3ef6ed5da78602a020c991775b0aff04"
 
 [[package]]
 name = "cc"
-version = "1.3.0"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c89588d05638b5b4594a3348a2d6c20277e43a7f5c5202b05cc56888475a47b8"
+checksum = "5add81bb678e6cb321aff7fa0dc7689ad82b112dbc032cea19f91d6b8e3582b9"
 dependencies = [
  "find-msvc-tools",
  "shlex",
@@ -1718,7 +1718,7 @@ dependencies = [
 [[package]]
 name = "federation-net"
 version = "0.1.0"
-source = "git+https://gt.hexor.cy/ab/frid.git#512a818a6a52ec713678e9a4e1cf0f50bb1e34ab"
+source = "git+https://gt.hexor.cy/ab/frid.git#e5353fa9b93d78be6cd811b8430d7dd5e725e6e5"
 dependencies = [
  "blake3",
  "data-encoding",
@@ -3622,7 +3622,7 @@ dependencies = [
 [[package]]
 name = "music-dht"
 version = "0.1.0"
-source = "git+https://gt.hexor.cy/ab/frid.git#512a818a6a52ec713678e9a4e1cf0f50bb1e34ab"
+source = "git+https://gt.hexor.cy/ab/frid.git#e5353fa9b93d78be6cd811b8430d7dd5e725e6e5"
 dependencies = [
  "async-trait",
  "blake3",
@@ -3633,6 +3633,7 @@ dependencies = [
  "rand 0.9.5",
  "rusqlite",
  "serde",
+ "serde_json",
  "thiserror 2.0.19",
  "tokio",
  "tracing",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "furumusic"
-version = "0.7.1"
+version = "0.8.0"
 edition = "2024"
 description = "Reusable web-app boilerplate: auth, OIDC/SSO, admin panel, user management, i18n, PostgreSQL"
 

src/federation/mod.rs

@@ -12,6 +12,7 @@
 //! `federation_network_id`) and apply on the fly — saving the settings
 //! starts, stops or re-joins the node without a server restart.
 
+pub mod devices;
 mod serve;
 mod storage;
 
@@ -196,6 +197,7 @@ impl Federation {
             .rendezvous(RendezvousConfig::default())
             .stream_protocol(AUDIO_ALPN)
             .stream_protocol(CATALOG_ALPN)
+            .stream_protocol(devices::SYNC_ALPN)
             .build()
             .map_err(|err| anyhow::anyhow!("invalid federation config: {err}"))?;
         let (service, mut events) =
@@ -240,15 +242,34 @@ impl Federation {
             .map_err(|err| anyhow::anyhow!("failed to take the catalog acceptor: {err}"))?;
         let catalog_task = tokio::spawn(serve::serve_catalog(
             catalog_acceptor,
-            pool,
+            pool.clone(),
             storage_dir,
             service.endpoint_id(),
         ));
+        let device_acceptor = service
+            .stream_acceptor(devices::SYNC_ALPN)
+            .map_err(|err| anyhow::anyhow!("failed to take the device-sync acceptor: {err}"))?;
+        let device_hub = crate::player::PlayerDeviceHub::shared();
+        let device_task = tokio::spawn(devices::serve_peers(
+            device_acceptor,
+            pool.clone(),
+            Arc::clone(&service),
+            Arc::clone(&device_hub),
+        ));
+        let device_sync_task =
+            tokio::spawn(devices::sync_loop(pool, Arc::clone(&service), device_hub));
 
         *guard = Some(Running {
             service,
             network_name,
-            tasks: vec![event_task, sync_task, audio_task, catalog_task],
+            tasks: vec![
+                event_task,
+                sync_task,
+                audio_task,
+                catalog_task,
+                device_task,
+                device_sync_task,
+            ],
         });
         self.set_error(None);
         drop(guard);
@@ -607,6 +628,118 @@ impl Federation {
             .map_err(|err| anyhow::anyhow!("connect failed: {err}"))?;
         Ok(peer.to_string())
     }
+
+    pub async fn fed_device_status(
+        &self,
+        user_id: i64,
+        user_name: &str,
+    ) -> Result<devices::FedDeviceStatus> {
+        let pool = self.pool().await?;
+        devices::status(&pool, user_id, user_name).await
+    }
+
+    pub async fn fed_device_invite(&self, user_id: i64, user_name: &str) -> Result<String> {
+        let service = self.service().await?;
+        let pool = self.pool().await?;
+        devices::create_invite(&pool, service, user_id, user_name).await
+    }
+
+    pub async fn fed_device_connect(
+        &self,
+        user_id: i64,
+        user_name: &str,
+        invite: &str,
+    ) -> Result<String> {
+        let network_id = devices::invite_network_id(invite)?;
+        {
+            let guard = self.running.lock().await;
+            let Some(running) = guard.as_ref() else {
+                anyhow::bail!("federation is not running");
+            };
+            let expected = NetworkId::from_name(&running.network_name);
+            anyhow::ensure!(
+                network_id == expected,
+                "device invite belongs to a different federation network"
+            );
+        }
+        let service = self.service().await?;
+        let pool = self.pool().await?;
+        devices::connect_invite(
+            &pool,
+            service,
+            crate::player::PlayerDeviceHub::shared(),
+            user_id,
+            user_name,
+            invite,
+        )
+        .await
+    }
+
+    pub async fn fed_device_answer_pairing(
+        &self,
+        user_id: i64,
+        request_id: &str,
+        accept: bool,
+        use_requester_group: bool,
+    ) -> Result<()> {
+        let pool = self.pool().await?;
+        devices::answer_pairing(&pool, user_id, request_id, accept, use_requester_group).await
+    }
+
+    pub async fn fed_device_revoke(&self, user_id: i64, device_id: &str) -> Result<()> {
+        let pool = self.pool().await?;
+        devices::revoke_device(&pool, user_id, device_id).await
+    }
+
+    pub async fn fed_device_sync_now(&self, user_id: i64) -> Result<()> {
+        let service = self.service().await?;
+        let pool = self.pool().await?;
+        devices::sync_once(
+            &pool,
+            service,
+            crate::player::PlayerDeviceHub::shared(),
+            user_id,
+        )
+        .await
+    }
+
+    pub async fn fed_device_web_command(
+        &self,
+        user_id: i64,
+        target_device_id: &str,
+        command: &str,
+        payload: serde_json::Value,
+        current_state: Option<serde_json::Value>,
+    ) -> Result<serde_json::Value> {
+        let pool = self.pool().await?;
+        devices::record_web_playback_command(
+            &pool,
+            user_id,
+            target_device_id,
+            command,
+            payload,
+            current_state,
+        )
+        .await
+    }
+
+    pub async fn fed_device_web_active_transfer(
+        &self,
+        user_id: i64,
+        target_device_id: &str,
+        previous_device_id: Option<&str>,
+        state: serde_json::Value,
+    ) -> Result<()> {
+        let pool = self.pool().await?;
+        devices::record_web_active_transfer(
+            &pool,
+            user_id,
+            target_device_id,
+            previous_device_id,
+            state,
+        )
+        .await
+    }
 }
 
 async fn persist_content_id(

src/music/mod.rs

@@ -1951,6 +1951,278 @@ pub mod db_migrations {
             &[Operation::custom(create_playlist_share_links).build()];
     }
 
+    #[cot::db::migrations::migration_op]
+    async fn create_fed_device_sync(ctx: migrations::MigrationContext<'_>) -> cot::db::Result<()> {
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__federation_content_id_cache (
+                    media_file_id BIGINT PRIMARY KEY,
+                    sha256_hash TEXT NOT NULL,
+                    content_id TEXT NOT NULL,
+                    updated_at TEXT NOT NULL
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE INDEX IF NOT EXISTS idx_furumusic_federation_content_id_cache_content_id
+                   ON furumusic__federation_content_id_cache (content_id)",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_device_identity (
+                    user_id BIGINT PRIMARY KEY,
+                    device_id TEXT NOT NULL UNIQUE,
+                    group_id TEXT NOT NULL,
+                    device_name TEXT NOT NULL,
+                    local_seq BIGINT NOT NULL DEFAULT 0,
+                    last_hlc_ms BIGINT NOT NULL DEFAULT 0,
+                    local_seeded_at_ms BIGINT NOT NULL DEFAULT 0,
+                    last_sync TEXT,
+                    last_error TEXT
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_device (
+                    user_id BIGINT NOT NULL,
+                    device_id TEXT NOT NULL,
+                    name TEXT NOT NULL DEFAULT '',
+                    client_version TEXT NOT NULL DEFAULT '',
+                    protocol_version INTEGER NOT NULL DEFAULT 1,
+                    endpoint_id TEXT NOT NULL DEFAULT '',
+                    endpoint_ticket TEXT NOT NULL DEFAULT '',
+                    trusted_at_ms BIGINT,
+                    last_seen_ms BIGINT,
+                    revoked_at_ms BIGINT,
+                    revoked_by TEXT,
+                    revoke_cutoff_seq BIGINT,
+                    PRIMARY KEY (user_id, device_id)
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE UNIQUE INDEX IF NOT EXISTS idx_fed_device_single_user
+                   ON furumusic__fed_device (device_id)
+                 WHERE trusted_at_ms IS NOT NULL",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_device_invite (
+                    invite_id TEXT PRIMARY KEY,
+                    user_id BIGINT NOT NULL,
+                    secret_hash TEXT NOT NULL,
+                    expires_at_ms BIGINT NOT NULL,
+                    created_at_ms BIGINT NOT NULL,
+                    used_at_ms BIGINT
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_pending_pairing (
+                    request_id TEXT PRIMARY KEY,
+                    user_id BIGINT NOT NULL,
+                    device_id TEXT NOT NULL,
+                    name TEXT NOT NULL,
+                    client_version TEXT NOT NULL,
+                    endpoint_id TEXT NOT NULL,
+                    endpoint_ticket TEXT NOT NULL,
+                    invite_id TEXT NOT NULL,
+                    created_at_ms BIGINT NOT NULL,
+                    answered_at_ms BIGINT,
+                    status TEXT NOT NULL,
+                    requester_group_id TEXT,
+                    requester_group_active_devices BIGINT NOT NULL DEFAULT 1,
+                    requester_group_devices_json TEXT NOT NULL DEFAULT '[]',
+                    use_requester_group BOOLEAN NOT NULL DEFAULT false
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE INDEX IF NOT EXISTS idx_fed_pending_pairing_user_status
+                   ON furumusic__fed_pending_pairing (user_id, status, created_at_ms DESC)",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_sync_ops (
+                    user_id BIGINT NOT NULL,
+                    op_id TEXT NOT NULL,
+                    origin_device_id TEXT NOT NULL,
+                    seq BIGINT NOT NULL,
+                    kind TEXT NOT NULL,
+                    payload_json JSONB NOT NULL,
+                    hlc_ms BIGINT NOT NULL,
+                    received_at_ms BIGINT NOT NULL,
+                    tombstone BOOLEAN NOT NULL DEFAULT false,
+                    PRIMARY KEY (user_id, op_id)
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE INDEX IF NOT EXISTS idx_fed_sync_ops_origin_seq
+                   ON furumusic__fed_sync_ops (user_id, origin_device_id, seq)",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE INDEX IF NOT EXISTS idx_fed_sync_ops_tombstone
+                   ON furumusic__fed_sync_ops (user_id, tombstone)",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_sync_vector (
+                    user_id BIGINT NOT NULL,
+                    device_id TEXT NOT NULL,
+                    max_seq BIGINT NOT NULL,
+                    PRIMARY KEY (user_id, device_id)
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_peer_ack (
+                    user_id BIGINT NOT NULL,
+                    peer_device_id TEXT NOT NULL,
+                    origin_device_id TEXT NOT NULL,
+                    max_seq BIGINT NOT NULL,
+                    updated_at_ms BIGINT NOT NULL,
+                    PRIMARY KEY (user_id, peer_device_id, origin_device_id)
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_state_like (
+                    user_id BIGINT NOT NULL,
+                    content_id TEXT NOT NULL,
+                    liked BOOLEAN NOT NULL,
+                    hlc_ms BIGINT NOT NULL,
+                    op_id TEXT NOT NULL,
+                    local_track_id BIGINT,
+                    fed_json JSONB,
+                    PRIMARY KEY (user_id, content_id)
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_state_playlist (
+                    user_id BIGINT NOT NULL,
+                    playlist_id TEXT NOT NULL,
+                    local_playlist_id BIGINT,
+                    title TEXT NOT NULL,
+                    deleted BOOLEAN NOT NULL DEFAULT false,
+                    hlc_ms BIGINT NOT NULL,
+                    op_id TEXT NOT NULL,
+                    PRIMARY KEY (user_id, playlist_id)
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE UNIQUE INDEX IF NOT EXISTS idx_fed_state_playlist_local
+                   ON furumusic__fed_state_playlist (user_id, local_playlist_id)
+                 WHERE local_playlist_id IS NOT NULL",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_state_playlist_item (
+                    user_id BIGINT NOT NULL,
+                    playlist_id TEXT NOT NULL,
+                    content_id TEXT NOT NULL,
+                    present BOOLEAN NOT NULL DEFAULT true,
+                    position BIGINT NOT NULL DEFAULT 0,
+                    hlc_ms BIGINT NOT NULL,
+                    op_id TEXT NOT NULL,
+                    local_track_id BIGINT,
+                    fed_json JSONB,
+                    PRIMARY KEY (user_id, playlist_id, content_id)
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE INDEX IF NOT EXISTS idx_fed_state_playlist_item_playlist
+                   ON furumusic__fed_state_playlist_item
+                      (user_id, playlist_id, present, position)",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__fed_playback_applied (
+                    user_id BIGINT NOT NULL,
+                    op_id TEXT NOT NULL,
+                    applied_at_ms BIGINT NOT NULL,
+                    PRIMARY KEY (user_id, op_id)
+                )",
+            )
+            .await?;
+        Ok(())
+    }
+
+    #[derive(Debug, Copy, Clone)]
+    pub struct M0038CreateFedDeviceSync;
+
+    impl migrations::Migration for M0038CreateFedDeviceSync {
+        const APP_NAME: &'static str = "furumusic";
+        const MIGRATION_NAME: &'static str = "m_0038_create_fed_device_sync";
+        const DEPENDENCIES: &'static [migrations::MigrationDependency] =
+            &[migrations::MigrationDependency::migration(
+                "furumusic",
+                "m_0037_create_playlist_share_links",
+            )];
+        const OPERATIONS: &'static [Operation] =
+            &[Operation::custom(create_fed_device_sync).build()];
+    }
+
+    #[cot::db::migrations::migration_op]
+    async fn ensure_federation_content_id_cache(
+        ctx: migrations::MigrationContext<'_>,
+    ) -> cot::db::Result<()> {
+        ctx.db
+            .raw(
+                "CREATE TABLE IF NOT EXISTS furumusic__federation_content_id_cache (
+                    media_file_id BIGINT PRIMARY KEY,
+                    sha256_hash TEXT NOT NULL,
+                    content_id TEXT NOT NULL,
+                    updated_at TEXT NOT NULL
+                )",
+            )
+            .await?;
+        ctx.db
+            .raw(
+                "CREATE INDEX IF NOT EXISTS idx_furumusic_federation_content_id_cache_content_id
+                   ON furumusic__federation_content_id_cache (content_id)",
+            )
+            .await?;
+        Ok(())
+    }
+
+    #[derive(Debug, Copy, Clone)]
+    pub struct M0039EnsureFederationContentIdCache;
+
+    impl migrations::Migration for M0039EnsureFederationContentIdCache {
+        const APP_NAME: &'static str = "furumusic";
+        const MIGRATION_NAME: &'static str = "m_0039_ensure_federation_content_id_cache";
+        const DEPENDENCIES: &'static [migrations::MigrationDependency] =
+            &[migrations::MigrationDependency::migration(
+                "furumusic",
+                "m_0038_create_fed_device_sync",
+            )];
+        const OPERATIONS: &'static [Operation] =
+            &[Operation::custom(ensure_federation_content_id_cache).build()];
+    }
+
     pub const MIGRATIONS: &[&SyncDynMigration] = &[
         &M0006CreateMediaFile,
         &M0007CreateArtist,
@@ -1979,5 +2251,7 @@ pub mod db_migrations {
         &M0035CreateEntityGenreTags,
         &M0036CreateExternalMetadataIds,
         &M0037CreatePlaylistShareLinks,
+        &M0038CreateFedDeviceSync,
+        &M0039EnsureFederationContentIdCache,
     ];
 }

src/player/dto.rs

@@ -272,6 +272,24 @@ pub(super) struct PlayerDevicesResponse {
     pub(super) playback_state: Option<PlayerDevicePlaybackStateDto>,
 }
 
+#[derive(Debug, Deserialize, JsonSchema)]
+pub(super) struct FedDeviceConnectRequest {
+    pub(super) invite: String,
+}
+
+#[derive(Debug, Deserialize, JsonSchema)]
+pub(super) struct FedDevicePairingAnswerRequest {
+    pub(super) request_id: String,
+    pub(super) accept: bool,
+    #[serde(default)]
+    pub(super) use_requester_group: bool,
+}
+
+#[derive(Debug, Deserialize, JsonSchema)]
+pub(super) struct FedDeviceRevokeRequest {
+    pub(super) device_id: String,
+}
+
 #[derive(Debug, Serialize, JsonSchema)]
 pub(super) struct PlayerDevicePollResponse {
     pub(super) device_id: String,

src/player/mod.rs

@@ -1,5 +1,5 @@
 use std::collections::{HashMap, HashSet, VecDeque};
-use std::sync::{Arc, Mutex};
+use std::sync::{Arc, Mutex, OnceLock};
 
 use cot::db::Database;
 use cot::http::StatusCode;
@@ -59,6 +59,7 @@ const PLAYER_JAM_MAX_INVITEES: usize = 25;
 const PLAYER_RADIO_TRACK_LIMIT: usize = 40;
 const PLAYER_RADIO_CANDIDATE_LIMIT: i64 = 220;
 const PLAYER_RADIO_RELEASE_SEED_TRACKS: i64 = 4;
+const FED_DEVICE_PREFIX: &str = "fed:";
 
 #[derive(Debug, Clone)]
 struct PlayerDevice {
@@ -108,11 +109,136 @@ struct PlayerDeviceHubState {
 }
 
 #[derive(Debug, Default)]
-struct PlayerDeviceHub {
+pub(crate) struct PlayerDeviceHub {
     state: Mutex<PlayerDeviceHubState>,
 }
 
 impl PlayerDeviceHub {
+    pub(crate) fn shared() -> Arc<Self> {
+        static HUB: OnceLock<Arc<PlayerDeviceHub>> = OnceLock::new();
+        Arc::clone(HUB.get_or_init(|| Arc::new(PlayerDeviceHub::default())))
+    }
+
+    pub(crate) fn enqueue_fed_command(
+        &self,
+        user_id: i64,
+        command: &str,
+        payload: serde_json::Value,
+    ) -> Result<(), &'static str> {
+        let now = current_millis();
+        let mut state = self.state.lock().expect("player device hub lock");
+        self.prune_locked(&mut state, now);
+        let devices = state
+            .devices_by_user
+            .get(&user_id)
+            .ok_or("no browser playback device")?;
+        let target = state
+            .active_device_by_user
+            .get(&user_id)
+            .filter(|id| !is_fed_virtual_device_id(id))
+            .filter(|id| devices.contains_key(*id))
+            .cloned()
+            .or_else(|| {
+                devices
+                    .values()
+                    .filter(|device| !is_fed_virtual_device_id(&device.id))
+                    .max_by_key(|device| device.last_seen_ms)
+                    .map(|device| device.id.clone())
+            })
+            .ok_or("no browser playback device")?;
+        state.active_device_by_user.insert(user_id, target.clone());
+        self.enqueue_command_locked(&mut state, user_id, &target, command, payload, now);
+        Ok(())
+    }
+
+    pub(crate) fn current_playback_state_json(&self, user_id: i64) -> Option<serde_json::Value> {
+        let state = self.state.lock().expect("player device hub lock");
+        if state
+            .active_device_by_user
+            .get(&user_id)
+            .is_some_and(|id| is_fed_virtual_device_id(id))
+        {
+            return None;
+        }
+        state
+            .playback_state_by_user
+            .get(&user_id)
+            .and_then(|playback| serde_json::to_value(playback).ok())
+    }
+
+    pub(crate) fn playback_state_json_for_commands(
+        &self,
+        user_id: i64,
+    ) -> Option<serde_json::Value> {
+        let now = current_millis();
+        let state = self.state.lock().expect("player device hub lock");
+        state
+            .playback_state_by_user
+            .get(&user_id)
+            .cloned()
+            .map(|playback| playback_state_at(playback, now))
+            .and_then(|playback| serde_json::to_value(playback).ok())
+    }
+
+    pub(crate) fn active_device_id_for_commands(&self, user_id: i64) -> Option<String> {
+        let state = self.state.lock().expect("player device hub lock");
+        state.active_device_by_user.get(&user_id).cloned()
+    }
+
+    pub(crate) fn fed_device_name_for_commands(
+        &self,
+        user_id: i64,
+        fed_device_id: &str,
+    ) -> Option<String> {
+        let virtual_id = fed_virtual_device_id(fed_device_id);
+        let state = self.state.lock().expect("player device hub lock");
+        state
+            .devices_by_user
+            .get(&user_id)
+            .and_then(|devices| devices.get(&virtual_id))
+            .map(|device| device.name.clone())
+    }
+
+    pub(crate) fn apply_fed_playback_state_json(
+        &self,
+        user_id: i64,
+        fed_device_id: &str,
+        fed_device_name: &str,
+        active: bool,
+        payload: serde_json::Value,
+    ) -> Result<(), &'static str> {
+        let mut playback_state: PlayerDevicePlaybackStateDto =
+            serde_json::from_value(payload).map_err(|_| "invalid playback state")?;
+        let now = current_millis();
+        playback_state.updated_at_ms = now;
+        let virtual_id = fed_virtual_device_id(fed_device_id);
+        let mut state = self.state.lock().expect("player device hub lock");
+        self.prune_locked(&mut state, now);
+        state.devices_by_user.entry(user_id).or_default().insert(
+            virtual_id.clone(),
+            PlayerDevice {
+                id: virtual_id.clone(),
+                name: fed_device_name.to_string(),
+                kind: "fed".to_string(),
+                last_seen_ms: now,
+            },
+        );
+        let should_update_playback = active
+            || state
+                .active_device_by_user
+                .get(&user_id)
+                .is_some_and(|active_id| active_id == &virtual_id);
+        if active {
+            state
+                .active_device_by_user
+                .insert(user_id, virtual_id.clone());
+        }
+        if should_update_playback {
+            state.playback_state_by_user.insert(user_id, playback_state);
+        }
+        Ok(())
+    }
+
     fn heartbeat(
         &self,
         user_id: i64,
@@ -194,7 +320,9 @@ impl PlayerDeviceHub {
                 state
                     .playback_state_by_user
                     .insert(user_id, transfer_state.clone());
-                if let Ok(payload) = serde_json::to_value(transfer_state) {
+                if !is_fed_virtual_device_id(target_device_id)
+                    && let Ok(payload) = serde_json::to_value(transfer_state)
+                {
                     self.enqueue_command_locked(
                         &mut state,
                         user_id,
@@ -772,6 +900,18 @@ fn current_millis() -> i64 {
     chrono::Utc::now().timestamp_millis()
 }
 
+fn fed_virtual_device_id(device_id: &str) -> String {
+    format!("{FED_DEVICE_PREFIX}{device_id}")
+}
+
+fn is_fed_virtual_device_id(device_id: &str) -> bool {
+    device_id.starts_with(FED_DEVICE_PREFIX)
+}
+
+fn fed_device_id_from_virtual(device_id: &str) -> Option<&str> {
+    device_id.strip_prefix(FED_DEVICE_PREFIX)
+}
+
 fn playback_state_at(
     mut playback_state: PlayerDevicePlaybackStateDto,
     now: i64,
@@ -796,7 +936,7 @@ fn normalize_device_id(raw: &str) -> Option<String> {
     }
     if !trimmed
         .chars()
-        .all(|ch| ch.is_ascii_alphanumeric() || ch == '-' || ch == '_')
+        .all(|ch| ch.is_ascii_alphanumeric() || ch == '-' || ch == '_' || ch == ':')
     {
         return None;
     }
@@ -949,6 +1089,14 @@ mod device_tests {
         );
         assert_eq!(device_kind_from_user_agent(user_agent), "phone");
     }
+
+    #[test]
+    fn accepts_virtual_fed_device_ids() {
+        assert_eq!(
+            normalize_device_id("fed:dev_e5ffc3b65642770c26c53ecf"),
+            Some("fed:dev_e5ffc3b65642770c26c53ecf".to_string())
+        );
+    }
 }
 
 #[derive(Debug, sqlx::FromRow)]
@@ -4533,6 +4681,7 @@ async fn devices_select_handler(
         .as_deref()
         .and_then(normalize_device_id)
         .unwrap_or_else(|| target_device_id.clone());
+    let previous_active_id = hub.active_device_id_for_commands(user.id);
 
     let Some(response) = hub.select(user.id, &current_device_id, &target_device_id) else {
         return Ok(json_error(
@@ -4540,6 +4689,28 @@ async fn devices_select_handler(
             "target device is offline",
         ));
     };
+    if let Some(fed_device_id) = fed_device_id_from_virtual(&target_device_id) {
+        let Some(playback_state) = response.playback_state.clone() else {
+            return Ok(json_error(
+                StatusCode::BAD_REQUEST,
+                "no playback state to transfer",
+            ));
+        };
+        let state = match serde_json::to_value(playback_state) {
+            Ok(state) => state,
+            Err(err) => return Ok(json_error(StatusCode::BAD_REQUEST, &format!("{err}"))),
+        };
+        let previous_fed_device_id = previous_active_id
+            .as_deref()
+            .and_then(fed_device_id_from_virtual)
+            .filter(|previous| *previous != fed_device_id);
+        if let Err(err) = crate::federation::handle()
+            .fed_device_web_active_transfer(user.id, fed_device_id, previous_fed_device_id, state)
+            .await
+        {
+            return Ok(json_error(StatusCode::BAD_REQUEST, &format!("{err}")));
+        }
+    }
     Json(response).into_response()
 }
 
@@ -4584,6 +4755,33 @@ async fn devices_command_handler(
         stamp_jam_queue_tracks(&mut payload, user.id, &user.name);
     }
 
+    if jam_id.is_none()
+        && let Some(fed_device_id) = target_device_id
+            .as_deref()
+            .and_then(fed_device_id_from_virtual)
+    {
+        let current_state = hub.playback_state_json_for_commands(user.id);
+        match crate::federation::handle()
+            .fed_device_web_command(user.id, fed_device_id, command, payload, current_state)
+            .await
+        {
+            Ok(next_state) => {
+                let name = hub
+                    .fed_device_name_for_commands(user.id, fed_device_id)
+                    .unwrap_or_else(|| fed_device_id.to_string());
+                let _ = hub.apply_fed_playback_state_json(
+                    user.id,
+                    fed_device_id,
+                    &name,
+                    true,
+                    next_state,
+                );
+                return Json(serde_json::json!({"ok": true})).into_response();
+            }
+            Err(err) => return Ok(json_error(StatusCode::BAD_REQUEST, &format!("{err}"))),
+        }
+    }
+
     match hub.enqueue_command(
         user.id,
         target_device_id.as_deref(),
@@ -4596,6 +4794,116 @@ async fn devices_command_handler(
     }
 }
 
+async fn fed_devices_status_handler(
+    auth_ctx: auth::AuthContext,
+    session: Session,
+    db: Database,
+) -> cot::Result<cot::response::Response> {
+    let Some(user) = auth::get_request_user(&auth_ctx, &session, &db).await else {
+        return Ok(json_error(StatusCode::UNAUTHORIZED, "not authenticated"));
+    };
+    match crate::federation::handle()
+        .fed_device_status(user.id, &user.name)
+        .await
+    {
+        Ok(status) => Json(status).into_response(),
+        Err(err) => Ok(json_error(StatusCode::BAD_REQUEST, &format!("{err}"))),
+    }
+}
+
+async fn fed_devices_invite_handler(
+    auth_ctx: auth::AuthContext,
+    session: Session,
+    db: Database,
+) -> cot::Result<cot::response::Response> {
+    let Some(user) = auth::get_request_user(&auth_ctx, &session, &db).await else {
+        return Ok(json_error(StatusCode::UNAUTHORIZED, "not authenticated"));
+    };
+    match crate::federation::handle()
+        .fed_device_invite(user.id, &user.name)
+        .await
+    {
+        Ok(invite) => Json(serde_json::json!({ "invite": invite })).into_response(),
+        Err(err) => Ok(json_error(StatusCode::BAD_REQUEST, &format!("{err}"))),
+    }
+}
+
+async fn fed_devices_connect_handler(
+    auth_ctx: auth::AuthContext,
+    session: Session,
+    db: Database,
+    Json(dto): Json<FedDeviceConnectRequest>,
+) -> cot::Result<cot::response::Response> {
+    let Some(user) = auth::get_request_user(&auth_ctx, &session, &db).await else {
+        return Ok(json_error(StatusCode::UNAUTHORIZED, "not authenticated"));
+    };
+    match crate::federation::handle()
+        .fed_device_connect(user.id, &user.name, dto.invite.trim())
+        .await
+    {
+        Ok(message) => Json(serde_json::json!({ "ok": true, "message": message })).into_response(),
+        Err(err) => Ok(json_error(StatusCode::BAD_REQUEST, &format!("{err}"))),
+    }
+}
+
+async fn fed_devices_pairing_handler(
+    auth_ctx: auth::AuthContext,
+    session: Session,
+    db: Database,
+    Json(dto): Json<FedDevicePairingAnswerRequest>,
+) -> cot::Result<cot::response::Response> {
+    let Some(user) = auth::get_request_user(&auth_ctx, &session, &db).await else {
+        return Ok(json_error(StatusCode::UNAUTHORIZED, "not authenticated"));
+    };
+    match crate::federation::handle()
+        .fed_device_answer_pairing(
+            user.id,
+            dto.request_id.trim(),
+            dto.accept,
+            dto.use_requester_group,
+        )
+        .await
+    {
+        Ok(()) => Json(serde_json::json!({ "ok": true })).into_response(),
+        Err(err) => Ok(json_error(StatusCode::BAD_REQUEST, &format!("{err}"))),
+    }
+}
+
+async fn fed_devices_revoke_handler(
+    auth_ctx: auth::AuthContext,
+    session: Session,
+    db: Database,
+    Json(dto): Json<FedDeviceRevokeRequest>,
+) -> cot::Result<cot::response::Response> {
+    let Some(user) = auth::get_request_user(&auth_ctx, &session, &db).await else {
+        return Ok(json_error(StatusCode::UNAUTHORIZED, "not authenticated"));
+    };
+    match crate::federation::handle()
+        .fed_device_revoke(user.id, dto.device_id.trim())
+        .await
+    {
+        Ok(()) => Json(serde_json::json!({ "ok": true })).into_response(),
+        Err(err) => Ok(json_error(StatusCode::BAD_REQUEST, &format!("{err}"))),
+    }
+}
+
+async fn fed_devices_sync_handler(
+    auth_ctx: auth::AuthContext,
+    session: Session,
+    db: Database,
+) -> cot::Result<cot::response::Response> {
+    let Some(user) = auth::get_request_user(&auth_ctx, &session, &db).await else {
+        return Ok(json_error(StatusCode::UNAUTHORIZED, "not authenticated"));
+    };
+    match crate::federation::handle()
+        .fed_device_sync_now(user.id)
+        .await
+    {
+        Ok(()) => Json(serde_json::json!({ "ok": true })).into_response(),
+        Err(err) => Ok(json_error(StatusCode::BAD_REQUEST, &format!("{err}"))),
+    }
+}
+
 fn stamp_jam_queue_tracks(payload: &mut serde_json::Value, user_id: i64, user_name: &str) {
     let Some(tracks) = payload
         .get_mut("tracks")
@@ -4618,6 +4926,103 @@ fn stamp_jam_queue_tracks(payload: &mut serde_json::Value, user_id: i64, user_na
     }
 }
 
+async fn record_fed_track_like(pool: &sqlx::PgPool, user_id: i64, track_id: i64, liked: bool) {
+    if let Err(err) =
+        crate::federation::devices::record_track_like(pool, user_id, track_id, liked).await
+    {
+        tracing::warn!(
+            track_id,
+            liked,
+            "fed device like op was not recorded: {err:#}"
+        );
+    }
+}
+
+async fn record_fed_playlist_created(
+    pool: &sqlx::PgPool,
+    user_id: i64,
+    playlist_id: i64,
+    title: &str,
+) {
+    if let Err(err) =
+        crate::federation::devices::record_playlist_created(pool, user_id, playlist_id, title).await
+    {
+        tracing::warn!(
+            playlist_id,
+            "fed device playlist create op was not recorded: {err:#}"
+        );
+    }
+}
+
+async fn record_fed_playlist_renamed(
+    pool: &sqlx::PgPool,
+    user_id: i64,
+    playlist_id: i64,
+    title: &str,
+) {
+    if let Err(err) =
+        crate::federation::devices::record_playlist_renamed(pool, user_id, playlist_id, title).await
+    {
+        tracing::warn!(
+            playlist_id,
+            "fed device playlist rename op was not recorded: {err:#}"
+        );
+    }
+}
+
+async fn record_fed_playlist_deleted(pool: &sqlx::PgPool, user_id: i64, playlist_id: i64) {
+    if let Err(err) =
+        crate::federation::devices::record_playlist_deleted(pool, user_id, playlist_id).await
+    {
+        tracing::warn!(
+            playlist_id,
+            "fed device playlist delete op was not recorded: {err:#}"
+        );
+    }
+}
+
+async fn record_fed_playlist_tracks_added(
+    pool: &sqlx::PgPool,
+    user_id: i64,
+    playlist_id: i64,
+    track_ids: &[i64],
+) {
+    if let Err(err) = crate::federation::devices::record_playlist_tracks_added(
+        pool,
+        user_id,
+        playlist_id,
+        track_ids,
+    )
+    .await
+    {
+        tracing::warn!(
+            playlist_id,
+            "fed device playlist add op was not recorded: {err:#}"
+        );
+    }
+}
+
+async fn record_fed_playlist_tracks_removed(
+    pool: &sqlx::PgPool,
+    user_id: i64,
+    playlist_id: i64,
+    content_ids: &[String],
+) {
+    if let Err(err) = crate::federation::devices::record_playlist_tracks_removed(
+        pool,
+        user_id,
+        playlist_id,
+        content_ids,
+    )
+    .await
+    {
+        tracing::warn!(
+            playlist_id,
+            "fed device playlist remove op was not recorded: {err:#}"
+        );
+    }
+}
+
 async fn jam_users_search_handler(
     auth_ctx: auth::AuthContext,
     session: Session,
@@ -5460,6 +5865,8 @@ async fn create_playlist_handler(
     .await
     .map_err(|e| cot::Error::internal(e.to_string()))?;
 
+    record_fed_playlist_created(pool, user.id, row.0, &title).await;
+
     Json(PlaylistCard {
         id: row.0,
         title,
@@ -5513,6 +5920,7 @@ async fn update_playlist_handler(
                 .execute(pool)
                 .await
                 .map_err(|e| cot::Error::internal(e.to_string()))?;
+            record_fed_playlist_renamed(pool, user.id, playlist_id, t).await;
         }
     }
     if let Some(desc) = &body.description {
@@ -5556,6 +5964,7 @@ async fn delete_playlist_handler(
     if owner.0 != user.id {
         return Ok(json_error(StatusCode::FORBIDDEN, "not your playlist"));
     }
+    record_fed_playlist_deleted(pool, user.id, playlist_id).await;
     sqlx::query("DELETE FROM furumusic__playlist_track WHERE playlist_id = $1")
         .bind(playlist_id)
         .execute(pool)
@@ -5638,6 +6047,8 @@ async fn add_tracks_to_playlist_handler(
         .await
         .map_err(|e| cot::Error::internal(e.to_string()))?;
 
+    record_fed_playlist_tracks_added(pool, user.id, playlist_id, &body.track_ids).await;
+
     Json(serde_json::json!({"ok": true})).into_response()
 }
 
@@ -5742,6 +6153,19 @@ async fn reorder_playlist_tracks_handler(
         .await
         .map_err(|e| cot::Error::internal(e.to_string()))?;
 
+    let reordered_track_ids = sqlx::query_scalar::<_, i64>(
+        r#"SELECT pt.track_id
+           FROM furumusic__playlist_track pt
+           JOIN furumusic__track t ON t.id = pt.track_id
+           WHERE pt.playlist_id = $1 AND t.is_hidden = false
+           ORDER BY pt.position"#,
+    )
+    .bind(playlist_id)
+    .fetch_all(pool)
+    .await
+    .map_err(|e| cot::Error::internal(e.to_string()))?;
+    record_fed_playlist_tracks_added(pool, user.id, playlist_id, &reordered_track_ids).await;
+
     Json(serde_json::json!({"ok": true})).into_response()
 }
 
@@ -5773,6 +6197,23 @@ async fn remove_track_from_playlist_handler(
     if owner.0 != user.id {
         return Ok(json_error(StatusCode::FORBIDDEN, "not your playlist"));
     }
+    let removed_content_ids = match crate::federation::devices::playlist_content_ids_for_removal(
+        pool,
+        playlist_id,
+        body.playlist_track_id,
+        body.track_id,
+    )
+    .await
+    {
+        Ok(ids) => ids,
+        Err(err) => {
+            tracing::warn!(
+                playlist_id,
+                "fed device playlist removal lookup failed: {err:#}"
+            );
+            Vec::new()
+        }
+    };
 
     match (body.playlist_track_id, body.track_id) {
         (Some(playlist_track_id), _) => {
@@ -5821,6 +6262,8 @@ async fn remove_track_from_playlist_handler(
         .await
         .map_err(|e| cot::Error::internal(e.to_string()))?;
 
+    record_fed_playlist_tracks_removed(pool, user.id, playlist_id, &removed_content_ids).await;
+
     Json(serde_json::json!({"ok": true})).into_response()
 }
 
@@ -5855,6 +6298,7 @@ async fn toggle_like_track_handler(
             .execute(pool)
             .await
             .map_err(|e| cot::Error::internal(e.to_string()))?;
+        record_fed_track_like(pool, user.id, track_id, false).await;
         Json(LikeStatus { liked: false }).into_response()
     } else {
         let now = chrono::Utc::now().format("%Y-%m-%dT%H:%M:%SZ").to_string();
@@ -5867,6 +6311,7 @@ async fn toggle_like_track_handler(
         .execute(pool)
         .await
         .map_err(|e| cot::Error::internal(e.to_string()))?;
+        record_fed_track_like(pool, user.id, track_id, true).await;
         Json(LikeStatus { liked: true }).into_response()
     }
 }
@@ -5887,16 +6332,17 @@ async fn like_release_handler(
     };
     let release_id = path.0.id;
     let now = chrono::Utc::now().format("%Y-%m-%dT%H:%M:%SZ").to_string();
-
-    // Check if ALL tracks in this release are already liked
-    let total: (i64,) = sqlx::query_as(
-        "SELECT COUNT(*) FROM furumusic__track WHERE release_id = $1 AND is_hidden = false",
+    let track_ids = sqlx::query_scalar::<_, i64>(
+        "SELECT id FROM furumusic__track WHERE release_id = $1 AND is_hidden = false",
     )
     .bind(release_id)
-    .fetch_one(pool)
+    .fetch_all(pool)
     .await
     .map_err(|e| cot::Error::internal(e.to_string()))?;
 
+    // Check if ALL tracks in this release are already liked
+    let total = track_ids.len() as i64;
+
     let liked_count: (i64,) = sqlx::query_as(
         r#"SELECT COUNT(*) FROM furumusic__user_liked_track ult
            JOIN furumusic__track t ON t.id = ult.track_id
@@ -5908,7 +6354,7 @@ async fn like_release_handler(
     .await
     .map_err(|e| cot::Error::internal(e.to_string()))?;
 
-    if liked_count.0 >= total.0 && total.0 > 0 {
+    if liked_count.0 >= total && total > 0 {
         // Unlike all tracks in release
         sqlx::query(
             r#"DELETE FROM furumusic__user_liked_track
@@ -5921,6 +6367,9 @@ async fn like_release_handler(
         .execute(pool)
         .await
         .map_err(|e| cot::Error::internal(e.to_string()))?;
+        for track_id in &track_ids {
+            record_fed_track_like(pool, user.id, *track_id, false).await;
+        }
         Json(LikeStatus { liked: false }).into_response()
     } else {
         // Like all tracks in release (skip already liked)
@@ -5940,6 +6389,9 @@ async fn like_release_handler(
         .execute(pool)
         .await
         .map_err(|e| cot::Error::internal(e.to_string()))?;
+        for track_id in &track_ids {
+            record_fed_track_like(pool, user.id, *track_id, true).await;
+        }
         Json(LikeStatus { liked: true }).into_response()
     }
 }
@@ -6600,7 +7052,7 @@ impl PlayerApp {
         Self {
             config,
             scheduler_handle,
-            device_hub: Arc::new(PlayerDeviceHub::default()),
+            device_hub: PlayerDeviceHub::shared(),
         }
     }
 }
@@ -8145,6 +8597,70 @@ impl App for PlayerApp {
                 }),
                 "player_devices_command",
             ),
+            // -- Federated TUI clients --
+            Route::with_handler_and_name(
+                "/fed-devices",
+                get(
+                    move |auth_ctx: auth::AuthContext, session: Session, db: Database| async move {
+                        fed_devices_status_handler(auth_ctx, session, db).await
+                    },
+                ),
+                "player_fed_devices",
+            ),
+            Route::with_handler_and_name(
+                "/fed-devices/invite",
+                post(
+                    move |auth_ctx: auth::AuthContext, session: Session, db: Database| async move {
+                        fed_devices_invite_handler(auth_ctx, session, db).await
+                    },
+                ),
+                "player_fed_devices_invite",
+            ),
+            Route::with_handler_and_name(
+                "/fed-devices/connect",
+                post(
+                    move |auth_ctx: auth::AuthContext,
+                          session: Session,
+                          db: Database,
+                          json: Json<FedDeviceConnectRequest>| async move {
+                        fed_devices_connect_handler(auth_ctx, session, db, json).await
+                    },
+                ),
+                "player_fed_devices_connect",
+            ),
+            Route::with_handler_and_name(
+                "/fed-devices/pairing",
+                post(
+                    move |auth_ctx: auth::AuthContext,
+                          session: Session,
+                          db: Database,
+                          json: Json<FedDevicePairingAnswerRequest>| async move {
+                        fed_devices_pairing_handler(auth_ctx, session, db, json).await
+                    },
+                ),
+                "player_fed_devices_pairing",
+            ),
+            Route::with_handler_and_name(
+                "/fed-devices/revoke",
+                post(
+                    move |auth_ctx: auth::AuthContext,
+                          session: Session,
+                          db: Database,
+                          json: Json<FedDeviceRevokeRequest>| async move {
+                        fed_devices_revoke_handler(auth_ctx, session, db, json).await
+                    },
+                ),
+                "player_fed_devices_revoke",
+            ),
+            Route::with_handler_and_name(
+                "/fed-devices/sync",
+                post(
+                    move |auth_ctx: auth::AuthContext, session: Session, db: Database| async move {
+                        fed_devices_sync_handler(auth_ctx, session, db).await
+                    },
+                ),
+                "player_fed_devices_sync",
+            ),
             Route::with_handler_and_name(
                 "/jams/users",
                 get({

templates/player/scripts.html

@@ -1251,7 +1251,12 @@ document.addEventListener('alpine:init', () => {
                         queue.currentIndex = Math.max(0, Math.min(Number(payload.index || 0), queue.tracks.length - 1));
                     }
                     const track = payload.track || queue.tracks[queue.currentIndex];
-                    if (track) this._playLocal(track, payload);
+                    if (track?.unavailable || (track && !track.stream_url)) {
+                        this._applyRemotePlaybackState({ ...payload, track, paused: true });
+                        this._pauseLocal();
+                    } else if (track) {
+                        this._playLocal(track, payload);
+                    }
                 } else if (command.command === 'pause') {
                     this.pause();
                 } else if (command.command === 'resume') {
@@ -1496,12 +1501,18 @@ document.addEventListener('alpine:init', () => {
         jamSelectedUsers: [],
         jamSearching: false,
         jamLocalPlayback: false,
+        fed: null,
+        fedInvite: '',
+        fedInviteInput: '',
+        fedBusy: false,
+        fedError: '',
         remoteHintVisible: false,
         remoteHintDeviceName: '',
         _remoteHintShown: false,
         _remoteHintTimer: null,
         _pollTimer: null,
         _jamSearchTimer: null,
+        _fedRefreshTick: 0,
         _stateRefreshTick: 0,
         _lastPlaybackState: null,
 
@@ -1509,9 +1520,13 @@ document.addEventListener('alpine:init', () => {
             this.id = this._ensureId();
             this.currentJamId = sessionStorage.getItem('furu_player_jam_id') || null;
             this.heartbeat();
+            this.loadFedDevices();
             this._pollTimer = setInterval(() => this.poll(), 500);
             document.addEventListener('visibilitychange', () => {
-                if (!document.hidden) this.poll();
+                if (!document.hidden) {
+                    this.poll();
+                    this.loadFedDevices();
+                }
             });
         },
 
@@ -1561,6 +1576,9 @@ document.addEventListener('alpine:init', () => {
                 const data = await res.json();
                 if (data.playback_state) this._lastPlaybackState = data.playback_state;
                 this._apply(data);
+                if (this.open || (++this._fedRefreshTick % 10 === 0)) {
+                    this.loadFedDevices();
+                }
 
                 const player = Alpine.store('player');
                 if (player && Array.isArray(data.commands)) {
@@ -1730,7 +1748,142 @@ document.addEventListener('alpine:init', () => {
         toggle() {
             this.dismissRemoteHint();
             this.open = !this.open;
-            if (this.open) this.poll();
+            if (this.open) {
+                this.poll();
+                this.loadFedDevices();
+            }
+        },
+
+        fedDevices() {
+            return (this.fed?.devices || []).filter(device => !device.revoked);
+        },
+
+        fedPending() {
+            return this.fed?.pending || [];
+        },
+
+        fedSummary() {
+            if (!this.fed) return 'Fed sync unavailable';
+            const outbox = Number(this.fed.outbox_ops || 0);
+            const unresolved = Number(this.fed.unresolved_items || 0);
+            return `${this.fed.active_devices || 0} linked · ${outbox} queued · ${unresolved} unresolved`;
+        },
+
+        async loadFedDevices() {
+            try {
+                const res = await fetch('/api/player/fed-devices');
+                if (!res.ok) {
+                    this.fedError = await this._errorText(res);
+                    return;
+                }
+                this.fed = await res.json();
+                this.fedError = '';
+            } catch (err) {
+                this.fedError = String(err?.message || err || 'Fed sync unavailable');
+            }
+        },
+
+        async generateFedInvite() {
+            if (this.fedBusy) return;
+            this.fedBusy = true;
+            try {
+                const res = await fetch('/api/player/fed-devices/invite', { method: 'POST' });
+                if (!res.ok) throw new Error(await this._errorText(res));
+                const data = await res.json();
+                this.fedInvite = data.invite || '';
+                if (this.fedInvite && navigator.clipboard?.writeText) {
+                    navigator.clipboard.writeText(this.fedInvite).catch(() => {});
+                }
+                await this.loadFedDevices();
+            } catch (err) {
+                this.fedError = String(err?.message || err || 'Invite failed');
+            } finally {
+                this.fedBusy = false;
+            }
+        },
+
+        async connectFedInvite() {
+            const invite = this.fedInviteInput.trim();
+            if (!invite || this.fedBusy) return;
+            this.fedBusy = true;
+            try {
+                const res = await fetch('/api/player/fed-devices/connect', {
+                    method: 'POST',
+                    headers: { 'Content-Type': 'application/json' },
+                    body: JSON.stringify({ invite }),
+                });
+                if (!res.ok) throw new Error(await this._errorText(res));
+                this.fedInviteInput = '';
+                await this.loadFedDevices();
+            } catch (err) {
+                this.fedError = String(err?.message || err || 'Connect failed');
+            } finally {
+                this.fedBusy = false;
+            }
+        },
+
+        async answerFedPairing(request, accept, useRequesterGroup = false) {
+            if (!request?.request_id || this.fedBusy) return;
+            this.fedBusy = true;
+            try {
+                const res = await fetch('/api/player/fed-devices/pairing', {
+                    method: 'POST',
+                    headers: { 'Content-Type': 'application/json' },
+                    body: JSON.stringify({
+                        request_id: request.request_id,
+                        accept,
+                        use_requester_group: useRequesterGroup,
+                    }),
+                });
+                if (!res.ok) throw new Error(await this._errorText(res));
+                await this.loadFedDevices();
+            } catch (err) {
+                this.fedError = String(err?.message || err || 'Pairing failed');
+            } finally {
+                this.fedBusy = false;
+            }
+        },
+
+        async revokeFedDevice(device) {
+            if (!device?.device_id || device.is_self || this.fedBusy) return;
+            if (!window.confirm(`Revoke ${device.name || device.device_id}?`)) return;
+            this.fedBusy = true;
+            try {
+                const res = await fetch('/api/player/fed-devices/revoke', {
+                    method: 'POST',
+                    headers: { 'Content-Type': 'application/json' },
+                    body: JSON.stringify({ device_id: device.device_id }),
+                });
+                if (!res.ok) throw new Error(await this._errorText(res));
+                await this.loadFedDevices();
+            } catch (err) {
+                this.fedError = String(err?.message || err || 'Revoke failed');
+            } finally {
+                this.fedBusy = false;
+            }
+        },
+
+        async syncFedDevices() {
+            if (this.fedBusy) return;
+            this.fedBusy = true;
+            try {
+                const res = await fetch('/api/player/fed-devices/sync', { method: 'POST' });
+                if (!res.ok) throw new Error(await this._errorText(res));
+                await this.loadFedDevices();
+            } catch (err) {
+                this.fedError = String(err?.message || err || 'Sync failed');
+            } finally {
+                this.fedBusy = false;
+            }
+        },
+
+        async _errorText(res) {
+            try {
+                const data = await res.json();
+                return data.error || res.statusText || 'Request failed';
+            } catch {
+                return res.statusText || 'Request failed';
+            }
         },
 
         async select(deviceId) {

templates/player/shell.html

@@ -1335,6 +1335,67 @@
                             </span>
                         </button>
                     </template>
+                    <div class="device-section-label fed-section-label">Fed Clients</div>
+                    <div class="fed-device-panel">
+                        <div class="fed-device-status" x-text="$store.devices.fedSummary()"></div>
+                        <template x-if="$store.devices.fedError">
+                            <div class="fed-device-error" x-text="$store.devices.fedError"></div>
+                        </template>
+                        <template x-for="request in $store.devices.fedPending()" :key="request.request_id">
+                            <div class="fed-pairing-card">
+                                <div class="fed-pairing-title" x-text="request.name || request.device_id"></div>
+                                <div class="fed-pairing-meta"
+                                     x-text="request.requester_group_id ? 'Already in another sync group' : (request.client_version || 'waiting for approval')"></div>
+                                <template x-if="request.requester_group_id">
+                                    <div class="fed-pairing-note">Recommended keeps the existing group intact.</div>
+                                </template>
+                                <div class="fed-device-actions">
+                                    <button class="fed-action-btn primary"
+                                            @click="$store.devices.answerFedPairing(request, true, !!request.requester_group_id)"
+                                            x-text="request.requester_group_id ? 'Recommended' : 'Approve'"></button>
+                                    <button class="fed-action-btn"
+                                            @click="$store.devices.answerFedPairing(request, false, false)">Cancel</button>
+                                </div>
+                            </div>
+                        </template>
+                        <template x-for="device in $store.devices.fedDevices()" :key="device.device_id">
+                            <div class="fed-device-row" :class="{ self: device.is_self }">
+                                <span class="fed-device-dot" :class="{ self: device.is_self }"></span>
+                                <span class="fed-device-main">
+                                    <span class="fed-device-name" x-text="device.name || device.device_id"></span>
+                                    <span class="fed-device-meta"
+                                          x-text="(device.is_self ? 'WEB' : (device.client_version || 'unknown'))"></span>
+                                </span>
+                                <button class="fed-revoke-btn"
+                                        x-show="!device.is_self"
+                                        @click="$store.devices.revokeFedDevice(device)">Revoke</button>
+                            </div>
+                        </template>
+                        <div class="fed-device-actions">
+                            <button class="fed-action-btn primary"
+                                    :disabled="$store.devices.fedBusy"
+                                    @click="$store.devices.generateFedInvite()">Invite</button>
+                            <button class="fed-action-btn"
+                                    :disabled="$store.devices.fedBusy"
+                                    @click="$store.devices.syncFedDevices()">Sync</button>
+                        </div>
+                        <template x-if="$store.devices.fedInvite">
+                            <input class="fed-device-input"
+                                   readonly
+                                   :value="$store.devices.fedInvite"
+                                   @focus="$event.target.select()">
+                        </template>
+                        <div class="fed-connect-row">
+                            <input class="fed-device-input"
+                                   type="text"
+                                   placeholder="Paste frid:// invite"
+                                   x-model="$store.devices.fedInviteInput"
+                                   @keydown.enter.prevent="$store.devices.connectFedInvite()">
+                            <button class="fed-action-btn"
+                                    :disabled="$store.devices.fedBusy || !$store.devices.fedInviteInput.trim()"
+                                    @click="$store.devices.connectFedInvite()">Connect</button>
+                        </div>
+                    </div>
                     <template x-if="$store.devices.jams.length > 0">
                         <div class="device-section-label jam-section-label">Jams</div>
                     </template>

templates/player/styles.html

@@ -1856,9 +1856,9 @@ button.user-stat:hover {
     position: absolute;
     right: 0;
     bottom: 38px;
-    width: 260px;
+    width: 320px;
     max-width: calc(100vw - 24px);
-    max-height: min(320px, calc(100dvh - var(--player-bar-space) - 24px));
+    max-height: min(440px, calc(100dvh - var(--player-bar-space) - 24px));
     overflow-y: auto;
     padding: 6px;
     border: 1px solid var(--border-color);
@@ -1955,6 +1955,142 @@ button.user-stat:hover {
     text-transform: uppercase;
 }
 
+.fed-section-label {
+    margin-top: 4px;
+    color: #b8d6ff;
+}
+
+.fed-device-panel {
+    margin: 2px 2px 6px;
+    padding: 8px;
+    border: 1px solid rgba(82,145,255,0.18);
+    border-radius: 6px;
+    background: rgba(82,145,255,0.045);
+    display: grid;
+    gap: 7px;
+}
+
+.fed-device-status,
+.fed-device-error,
+.fed-pairing-note {
+    color: var(--text-subdued);
+    font-size: 11px;
+    line-height: 1.35;
+}
+
+.fed-device-error {
+    color: #ffb2b2;
+}
+
+.fed-device-row {
+    min-height: 32px;
+    display: grid;
+    grid-template-columns: 9px minmax(0, 1fr) auto;
+    align-items: center;
+    gap: 8px;
+}
+
+.fed-device-dot {
+    width: 7px;
+    height: 7px;
+    border-radius: 999px;
+    background: #73d795;
+}
+
+.fed-device-dot.self {
+    background: #ffd166;
+}
+
+.fed-device-main {
+    min-width: 0;
+    display: grid;
+    gap: 1px;
+}
+
+.fed-device-name,
+.fed-pairing-title {
+    color: var(--text-primary);
+    font-size: 12px;
+    font-weight: 750;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+}
+
+.fed-device-meta,
+.fed-pairing-meta {
+    color: var(--text-subdued);
+    font-size: 11px;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+}
+
+.fed-pairing-card {
+    padding: 7px;
+    border-radius: 5px;
+    background: rgba(255,255,255,0.04);
+    display: grid;
+    gap: 5px;
+}
+
+.fed-device-actions,
+.fed-connect-row {
+    display: flex;
+    gap: 6px;
+    min-width: 0;
+}
+
+.fed-connect-row .fed-device-input {
+    flex: 1;
+}
+
+.fed-action-btn,
+.fed-revoke-btn {
+    height: 28px;
+    border: 0;
+    border-radius: 4px;
+    background: rgba(255,255,255,0.08);
+    color: var(--text-secondary);
+    padding: 0 8px;
+    font-size: 12px;
+    font-weight: 700;
+    cursor: pointer;
+}
+
+.fed-action-btn:hover,
+.fed-revoke-btn:hover {
+    background: rgba(255,255,255,0.13);
+    color: var(--text-primary);
+}
+
+.fed-action-btn.primary {
+    background: rgba(82,145,255,0.16);
+    color: #c9dcff;
+}
+
+.fed-action-btn:disabled {
+    opacity: 0.45;
+    cursor: default;
+}
+
+.fed-revoke-btn {
+    background: rgba(255,96,96,0.1);
+    color: #ffb2b2;
+}
+
+.fed-device-input {
+    width: 100%;
+    min-width: 0;
+    height: 30px;
+    border: 1px solid rgba(82,145,255,0.2);
+    border-radius: 4px;
+    background: rgba(0,0,0,0.18);
+    color: var(--text-primary);
+    padding: 0 8px;
+    font-size: 12px;
+}
+
 .jam-section-label,
 .jam-row,
 .start-jam-row,