// Playout / Master Control routes.
//
// Control plane for the CasparCG-backed playout subsystem. Channels are placed
// on cluster nodes and their engine containers spawned via the same Docker-socket
// / node-agent path recorders use; the channel's transport (play / pause / skip)
// is proxied through to the sidecar's HTTP shim, which drives CasparCG over AMCP.
//
// RBAC: every channel carries a project_id (NULL = admin-only, the recorder
// convention). List routes filter by accessible projects; mutating routes assert
// 'edit'. See docs/superpowers/specs/2026-05-30-playout-mcr-design.md.

import express from 'express';
import http from 'http';
import { Queue } from 'bullmq';
import pool from '../db/pool.js';
import { validateUuid } from '../middleware/errors.js';
import {
  assertProjectAccess, accessibleProjectIds, isAdmin,
} from '../auth/authz.js';

const router = express.Router();

// ── BullMQ: media staging queue (S3 -> /media volume) ────────────────────────
const parseRedisUrl = (url) => {
  const parsed = new URL(url);
  return { host: parsed.hostname, port: parseInt(parsed.port, 10) };
};
const stageQueue = new Queue('playout-stage', {
  connection: parseRedisUrl(process.env.REDIS_URL || 'redis://queue:6379'),
});

// ── Sidecar orchestration (mirrors recorders.js) ─────────────────────────────
const PLAYOUT_SIDECAR_IMAGE = process.env.PLAYOUT_IMAGE || 'wild-dragon-playout:latest';

function dockerApi(method, path, body = null) {
  return new Promise((resolve, reject) => {
    const options = {
      socketPath: '/var/run/docker.sock',
      path: `/v1.43${path}`,
      method,
      headers: { 'Content-Type': 'application/json' },
    };
    const req = http.request(options, (res) => {
      let data = '';
      res.on('data', (chunk) => (data += chunk));
      res.on('end', () => {
        try { resolve({ status: res.statusCode, data: data ? JSON.parse(data) : {} }); }
        catch { resolve({ status: res.statusCode, data }); }
      });
    });
    req.on('error', reject);
    req.setTimeout(10000, () => req.destroy(new Error('Docker API timeout after 10s')));
    if (body) req.write(JSON.stringify(body));
    req.end();
  });
}

async function resolveNodeTarget(nodeId) {
  if (!nodeId) return { remote: false };
  const r = await pool.query(
    'SELECT hostname, ip_address, api_url FROM cluster_nodes WHERE id = $1', [nodeId]
  );
  if (r.rows.length === 0) return { remote: false };
  const node = r.rows[0];
  const localHostname = process.env.NODE_HOSTNAME || '';
  if (!node.api_url || node.hostname === localHostname) return { remote: false };
  return { remote: true, apiUrl: node.api_url, ip: node.ip_address };
}

// The sidecar shim listens on this port inside the container. The mam-api talks
// to it by container alias on the shared docker network (local) or via the
// node-agent's returned host:port (remote).
const SIDECAR_HTTP_PORT = 3002;

function channelAlias(id) { return `playout-${id}`; }

// Resolve the base URL the API uses to reach a running channel's sidecar shim.
// Local: the docker-network alias. Remote: the node-agent reported the host the
// container is published on (stored in container_meta.sidecar_url).
function sidecarBaseUrl(channel) {
  if (channel.container_meta && channel.container_meta.sidecar_url) {
    return channel.container_meta.sidecar_url;
  }
  return `http://${channelAlias(channel.id)}:${SIDECAR_HTTP_PORT}`;
}

async function callSidecar(channel, path, method = 'POST', body = null) {
  const url = `${sidecarBaseUrl(channel)}${path}`;
  const res = await fetch(url, {
    method,
    headers: { 'Content-Type': 'application/json' },
    body: body ? JSON.stringify(body) : undefined,
    signal: AbortSignal.timeout(20000),
  });
  if (!res.ok) {
    const text = await res.text().catch(() => '');
    throw new Error(`sidecar ${method} ${path} -> HTTP ${res.status}: ${text.slice(0, 200)}`);
  }
  return res.json().catch(() => ({}));
}

// ── Serialization ────────────────────────────────────────────────────────────
function channelToJson(r) {
  return {
    id: r.id,
    name: r.name,
    node_id: r.node_id,
    output_type: r.output_type,
    output_config: r.output_config,
    video_format: r.video_format,
    status: r.status,
    container_id: r.container_id,
    error_message: r.error_message,
    project_id: r.project_id,
    restart_count: r.restart_count ?? 0,
    last_restart_at: r.last_restart_at,
    last_heartbeat_at: r.last_heartbeat_at,
    created_at: r.created_at,
    updated_at: r.updated_at,
  };
}

const OUTPUT_TYPES = new Set(['decklink', 'ndi', 'srt', 'rtmp']);

// ── Param resolver: scope every /:id route to the channel's project ──────────
router.param('id', async (req, res, next) => {
  validateUuid('id')(req, res, () => {});
  if (res.headersSent) return;
  try {
    const { rows } = await pool.query(
      'SELECT * FROM playout_channels WHERE id = $1', [req.params.id]
    );
    if (rows.length === 0) return res.status(404).json({ error: 'Channel not found' });
    req.channel = rows[0];
    await assertProjectAccess(req.user, req.channel.project_id, 'view');
    next();
  } catch (err) { next(err); }
});

async function requireChannelEdit(req, res, next) {
  try { await assertProjectAccess(req.user, req.channel.project_id, 'edit'); next(); }
  catch (err) { next(err); }
}

// ── Channels ─────────────────────────────────────────────────────────────────

// GET /playout/channels — list (filtered to accessible projects)
router.get('/channels', async (req, res, next) => {
  try {
    let rows;
    if (isAdmin(req.user)) {
      ({ rows } = await pool.query('SELECT * FROM playout_channels ORDER BY created_at DESC'));
    } else {
      const ids = await accessibleProjectIds(req.user);
      if (ids.length === 0) return res.json([]);
      ({ rows } = await pool.query(
        'SELECT * FROM playout_channels WHERE project_id = ANY($1) ORDER BY created_at DESC', [ids]
      ));
    }
    res.json(rows.map(channelToJson));
  } catch (err) { next(err); }
});

// POST /playout/channels — create
router.post('/channels', async (req, res, next) => {
  try {
    const { name, node_id = null, output_type = 'srt', output_config = {},
            video_format = '1080p5994', project_id = null } = req.body || {};
    if (!name || typeof name !== 'string') {
      return res.status(400).json({ error: 'name is required' });
    }
    if (!OUTPUT_TYPES.has(output_type)) {
      return res.status(400).json({ error: `output_type must be one of: ${[...OUTPUT_TYPES].join(', ')}` });
    }
    // Creating a project-scoped channel requires edit on that project; a
    // null-project (admin-only) channel requires admin.
    if (project_id) await assertProjectAccess(req.user, project_id, 'edit');
    else if (!isAdmin(req.user)) return res.status(403).json({ error: 'admin required for unassigned channel' });

    const { rows } = await pool.query(
      `INSERT INTO playout_channels (name, node_id, output_type, output_config, video_format, project_id)
       VALUES ($1,$2,$3,$4,$5,$6) RETURNING *`,
      [name.trim(), node_id, output_type, JSON.stringify(output_config), video_format, project_id]
    );
    res.status(201).json(channelToJson(rows[0]));
  } catch (err) { next(err); }
});

// PATCH /playout/channels/:id — update config (only while stopped)
router.patch('/channels/:id', requireChannelEdit, async (req, res, next) => {
  try {
    if (req.channel.status === 'running') {
      return res.status(409).json({ error: 'Cannot edit a running channel — stop it first' });
    }
    const allowed = ['name', 'node_id', 'output_type', 'output_config', 'video_format', 'project_id'];
    const sets = [];
    const vals = [];
    let i = 1;
    for (const k of allowed) {
      if (req.body[k] === undefined) continue;
      if (k === 'output_type' && !OUTPUT_TYPES.has(req.body[k])) {
        return res.status(400).json({ error: 'invalid output_type' });
      }
      sets.push(`${k} = $${i++}`);
      vals.push(k === 'output_config' ? JSON.stringify(req.body[k]) : req.body[k]);
    }
    if (sets.length === 0) return res.json(channelToJson(req.channel));
    vals.push(req.channel.id);
    const { rows } = await pool.query(
      `UPDATE playout_channels SET ${sets.join(', ')}, updated_at = NOW() WHERE id = $${i} RETURNING *`, vals
    );
    res.json(channelToJson(rows[0]));
  } catch (err) { next(err); }
});

// DELETE /playout/channels/:id
router.delete('/channels/:id', requireChannelEdit, async (req, res, next) => {
  try {
    if (req.channel.status === 'running') {
      return res.status(409).json({ error: 'Stop the channel before deleting it' });
    }
    await pool.query('DELETE FROM playout_channels WHERE id = $1', [req.channel.id]);
    res.json({ deleted: true });
  } catch (err) { next(err); }
});

// ── Port-contention guard (DeckLink) ─────────────────────────────────────────
// A DeckLink device on a node is exclusive: an active recorder OR another active
// channel on the same node+index blocks a new SDI channel. NDI/SRT/RTMP have no
// hardware contention.
async function assertDeckLinkFree(channel) {
  if (channel.output_type !== 'decklink') return;
  const idx = (channel.output_config && channel.output_config.device_index) || 1;
  // Another running channel on the same node + device index?
  const chan = await pool.query(
    `SELECT id FROM playout_channels
     WHERE id <> $1 AND node_id IS NOT DISTINCT FROM $2 AND status = 'running'
       AND output_type = 'decklink' AND (output_config->>'device_index')::int = $3`,
    [channel.id, channel.node_id, idx]
  );
  if (chan.rows.length > 0) {
    throw Object.assign(new Error(`DeckLink device ${idx} already in use by another channel on this node`), { httpStatus: 409 });
  }
  // An active recorder using the same device index on the same node?
  const rec = await pool.query(
    `SELECT id FROM recorders
     WHERE node_id IS NOT DISTINCT FROM $1 AND device_index = $2
       AND status = 'recording' AND source_type = 'sdi'`,
    [channel.node_id, idx]
  );
  if (rec.rows.length > 0) {
    throw Object.assign(new Error(`DeckLink device ${idx} is in use by a recorder on this node`), { httpStatus: 409 });
  }
}

// POST /playout/channels/:id/start — spawn the CasparCG sidecar + bring up output
router.post('/channels/:id/start', requireChannelEdit, async (req, res, next) => {
  try {
    const channel = req.channel;
    if (channel.status === 'running' || channel.status === 'starting') {
      return res.status(409).json({ error: `Channel already ${channel.status}` });
    }
    await assertDeckLinkFree(channel);

    await pool.query('UPDATE playout_channels SET status = $1, error_message = NULL WHERE id = $2', ['starting', channel.id]);

    const env = [
      `OUTPUT_TYPE=${channel.output_type}`,
      `OUTPUT_CONFIG=${JSON.stringify(channel.output_config || {})}`,
      `VIDEO_FORMAT=${channel.video_format}`,
      `PORT=${SIDECAR_HTTP_PORT}`,
      // Drives the HLS preview path (/media/live/<channel_id>/index.m3u8) and
      // the per-channel resource naming inside the sidecar.
      `CHANNEL_ID=${channel.id}`,
    ];

    const { remote: isRemote, apiUrl: targetNodeApiUrl } = await resolveNodeTarget(channel.node_id);
    const dockerNetwork = process.env.DOCKER_NETWORK || 'wild-dragon_wild-dragon';
    let containerId;
    let containerMeta = {};

    if (isRemote) {
      const sidecarRes = await fetch(`${targetNodeApiUrl}/sidecar/start`, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          image: PLAYOUT_SIDECAR_IMAGE, env,
          capturePort: SIDECAR_HTTP_PORT,
          sourceType: channel.output_type,
          useGpu: false,
          publishHttp: true,
        }),
        signal: AbortSignal.timeout(20000),
      });
      if (!sidecarRes.ok) {
        const details = await sidecarRes.json().catch(() => ({}));
        console.error('[playout] remote sidecar start failed:', JSON.stringify(details));
        await pool.query('UPDATE playout_channels SET status = $1, error_message = $2 WHERE id = $3',
          ['error', 'remote node failed to start sidecar', channel.id]);
        return res.status(502).json({ error: 'Remote node failed to start sidecar' });
      }
      const data = await sidecarRes.json();
      containerId = data.containerId;
      // node-agent returns the reachable host:port the shim is published on.
      if (data.sidecarUrl || data.host) {
        containerMeta.sidecar_url = data.sidecarUrl || `http://${data.host}:${SIDECAR_HTTP_PORT}`;
      }
    } else {
      const alias = channelAlias(channel.id);
      const hostBinds = ['/mnt/NVME/MAM/wild-dragon-media:/media'];
      if (channel.output_type === 'decklink') hostBinds.push('/dev/blackmagic:/dev/blackmagic');

      const containerConfig = {
        Image: PLAYOUT_SIDECAR_IMAGE,
        Env: env,
        HostConfig: {
          Privileged: true,
          NetworkMode: dockerNetwork,
          Binds: hostBinds,
        },
        NetworkingConfig: { EndpointsConfig: { [dockerNetwork]: { Aliases: [alias] } } },
        Hostname: alias,
      };
      const createRes = await dockerApi('POST', '/containers/create', containerConfig);
      if (createRes.status !== 201) {
        console.error('[playout] container create failed:', JSON.stringify(createRes.data));
        await pool.query('UPDATE playout_channels SET status = $1, error_message = $2 WHERE id = $3',
          ['error', 'container create failed', channel.id]);
        return res.status(500).json({ error: 'Failed to create container' });
      }
      containerId = createRes.data.Id;
      const startRes = await dockerApi('POST', `/containers/${containerId}/start`);
      if (startRes.status !== 204) {
        console.error('[playout] container start failed:', JSON.stringify(startRes.data));
        await dockerApi('DELETE', `/containers/${containerId}?force=true`).catch(() => {});
        await pool.query('UPDATE playout_channels SET status = $1, error_message = $2 WHERE id = $3',
          ['error', 'container start failed', channel.id]);
        return res.status(500).json({ error: 'Failed to start container' });
      }
    }

    const { rows } = await pool.query(
      `UPDATE playout_channels
       SET status = 'running', container_id = $1, container_meta = $2, updated_at = NOW()
       WHERE id = $3 RETURNING *`,
      [containerId, JSON.stringify(containerMeta), channel.id]
    );
    res.json(channelToJson(rows[0]));
  } catch (err) {
    if (err.httpStatus) return res.status(err.httpStatus).json({ error: err.message });
    next(err);
  }
});

// POST /playout/channels/:id/stop — tear down the sidecar
router.post('/channels/:id/stop', requireChannelEdit, async (req, res, next) => {
  try {
    const channel = req.channel;
    if (channel.container_id) {
      const { remote: isRemote, apiUrl } = await resolveNodeTarget(channel.node_id);
      if (isRemote) {
        await fetch(`${apiUrl}/sidecar/stop`, {
          method: 'POST', headers: { 'Content-Type': 'application/json' },
          body: JSON.stringify({ containerId: channel.container_id }),
          signal: AbortSignal.timeout(20000),
        }).catch((e) => console.error('[playout] remote stop failed:', e.message));
      } else {
        await dockerApi('POST', `/containers/${channel.container_id}/stop?t=10`).catch(() => {});
        await dockerApi('DELETE', `/containers/${channel.container_id}?force=true`).catch(() => {});
      }
    }
    const { rows } = await pool.query(
      `UPDATE playout_channels SET status = 'stopped', container_id = NULL, updated_at = NOW()
       WHERE id = $1 RETURNING *`, [channel.id]
    );
    res.json(channelToJson(rows[0]));
  } catch (err) { next(err); }
});

// GET /playout/channels/:id/status — live engine status (proxied to sidecar)
router.get('/channels/:id/status', async (req, res, next) => {
  try {
    if (req.channel.status !== 'running') {
      return res.json({ running: false, status: req.channel.status });
    }
    const out = await callSidecar(req.channel, '/status', 'GET');
    res.json({ running: true, status: req.channel.status, engine: out });
  } catch (err) {
    res.json({ running: true, status: req.channel.status, engine: null, engine_error: err.message });
  }
});

// ── Transport ────────────────────────────────────────────────────────────────
async function transport(req, res, action, body = null) {
  if (req.channel.status !== 'running') {
    return res.status(409).json({ error: 'Channel is not running' });
  }
  try { res.json(await callSidecar(req.channel, action, 'POST', body)); }
  catch (err) { res.status(502).json({ error: err.message }); }
}

// POST /playout/channels/:id/play — resolve the channel's playlist, stage-check,
// and hand the engine the ordered list of ready clips.
router.post('/channels/:id/play', requireChannelEdit, async (req, res, next) => {
  try {
    if (req.channel.status !== 'running') {
      return res.status(409).json({ error: 'Start the channel before playing' });
    }
    const { playlist_id } = req.body || {};
    if (!playlist_id) return res.status(400).json({ error: 'playlist_id is required' });

    const pl = await pool.query('SELECT * FROM playout_playlists WHERE id = $1 AND channel_id = $2',
      [playlist_id, req.channel.id]);
    if (pl.rows.length === 0) return res.status(404).json({ error: 'Playlist not found for this channel' });

    const items = await pool.query(
      `SELECT i.*, a.filename AS clip_name
       FROM playout_items i JOIN assets a ON a.id = i.asset_id
       WHERE i.playlist_id = $1 ORDER BY i.sort_order ASC`, [playlist_id]);

    const notReady = items.rows.filter((i) => i.media_status !== 'ready' || !i.media_path);
    if (notReady.length > 0) {
      return res.status(409).json({
        error: 'Some items are not staged yet',
        pending: notReady.map((i) => i.id),
      });
    }

    const payload = {
      loop: pl.rows[0].loop,
      items: items.rows.map((i) => ({
        id: i.id, asset_id: i.asset_id, media_path: i.media_path,
        in_point: i.in_point ? Number(i.in_point) : null,
        out_point: i.out_point ? Number(i.out_point) : null,
        transition: i.transition, transition_ms: i.transition_ms,
        clip_name: i.clip_name,
      })),
    };
    const out = await callSidecar(req.channel, '/playlist/load', 'POST', payload);
    res.json(out);
  } catch (err) { next(err); }
});

router.post('/channels/:id/pause',  requireChannelEdit, (req, res) => transport(req, res, '/transport/pause'));
router.post('/channels/:id/resume', requireChannelEdit, (req, res) => transport(req, res, '/transport/resume'));
router.post('/channels/:id/skip',   requireChannelEdit, (req, res) => transport(req, res, '/transport/skip'));
router.post('/channels/:id/stop-playback', requireChannelEdit, (req, res) => transport(req, res, '/channel/stop'));

// GET /playout/channels/:id/asrun — as-run log
router.get('/channels/:id/asrun', async (req, res, next) => {
  try {
    const { rows } = await pool.query(
      `SELECT * FROM playout_as_run WHERE channel_id = $1 ORDER BY started_at DESC LIMIT 500`,
      [req.channel.id]);
    res.json(rows);
  } catch (err) { next(err); }
});

// ── Playlists ────────────────────────────────────────────────────────────────
async function loadChannelForBody(req, res, next) {
  // For playlist/item routes the channel is referenced indirectly; resolve it
  // and assert edit. Used on create/mutate routes that carry channel_id.
  const channelId = req.body.channel_id || req.query.channel_id;
  if (!channelId) return res.status(400).json({ error: 'channel_id is required' });
  try {
    const { rows } = await pool.query('SELECT * FROM playout_channels WHERE id = $1', [channelId]);
    if (rows.length === 0) return res.status(404).json({ error: 'Channel not found' });
    req.channel = rows[0];
    await assertProjectAccess(req.user, req.channel.project_id, 'edit');
    next();
  } catch (err) { next(err); }
}

// GET /playout/playlists?channel_id=...
router.get('/playlists', async (req, res, next) => {
  try {
    const channelId = req.query.channel_id;
    if (!channelId) return res.status(400).json({ error: 'channel_id is required' });
    const ch = await pool.query('SELECT project_id FROM playout_channels WHERE id = $1', [channelId]);
    if (ch.rows.length === 0) return res.status(404).json({ error: 'Channel not found' });
    await assertProjectAccess(req.user, ch.rows[0].project_id, 'view');
    const { rows } = await pool.query(
      'SELECT * FROM playout_playlists WHERE channel_id = $1 ORDER BY created_at ASC', [channelId]);
    res.json(rows);
  } catch (err) { next(err); }
});

// POST /playout/playlists
router.post('/playlists', loadChannelForBody, async (req, res, next) => {
  try {
    const { name, loop = false } = req.body || {};
    if (!name) return res.status(400).json({ error: 'name is required' });
    const { rows } = await pool.query(
      'INSERT INTO playout_playlists (channel_id, name, loop) VALUES ($1,$2,$3) RETURNING *',
      [req.channel.id, name.trim(), !!loop]);
    res.status(201).json(rows[0]);
  } catch (err) { next(err); }
});

// GET /playout/playlists/:plid/items
router.get('/playlists/:plid/items', validateUuid('plid'), async (req, res, next) => {
  try {
    const pl = await pool.query(
      `SELECT p.*, c.project_id FROM playout_playlists p
       JOIN playout_channels c ON c.id = p.channel_id WHERE p.id = $1`, [req.params.plid]);
    if (pl.rows.length === 0) return res.status(404).json({ error: 'Playlist not found' });
    await assertProjectAccess(req.user, pl.rows[0].project_id, 'view');
    const { rows } = await pool.query(
      `SELECT i.*, a.filename AS clip_name, a.duration_ms AS asset_duration_ms
       FROM playout_items i JOIN assets a ON a.id = i.asset_id
       WHERE i.playlist_id = $1 ORDER BY i.sort_order ASC`, [req.params.plid]);
    res.json(rows);
  } catch (err) { next(err); }
});

// Helper: load a playlist + assert edit on its channel's project.
async function loadPlaylistEdit(plid, user) {
  const pl = await pool.query(
    `SELECT p.*, c.project_id FROM playout_playlists p
     JOIN playout_channels c ON c.id = p.channel_id WHERE p.id = $1`, [plid]);
  if (pl.rows.length === 0) { throw Object.assign(new Error('Playlist not found'), { httpStatus: 404 }); }
  await assertProjectAccess(user, pl.rows[0].project_id, 'edit');
  return pl.rows[0];
}

// POST /playout/playlists/:plid/items — add an asset to a playlist
router.post('/playlists/:plid/items', validateUuid('plid'), async (req, res, next) => {
  try {
    await loadPlaylistEdit(req.params.plid, req.user);
    const { asset_id, in_point = null, out_point = null,
            transition = 'cut', transition_ms = 0 } = req.body || {};
    if (!asset_id) return res.status(400).json({ error: 'asset_id is required' });

    // Append at the end of the playlist.
    const ord = await pool.query(
      'SELECT COALESCE(MAX(sort_order), -1) + 1 AS next FROM playout_items WHERE playlist_id = $1',
      [req.params.plid]);
    const { rows } = await pool.query(
      `INSERT INTO playout_items (playlist_id, asset_id, sort_order, in_point, out_point, transition, transition_ms)
       VALUES ($1,$2,$3,$4,$5,$6,$7) RETURNING *`,
      [req.params.plid, asset_id, ord.rows[0].next, in_point, out_point, transition, transition_ms]);

    // Kick staging immediately so the clip is air-ready by the time the operator
    // hits play.
    await stageQueue.add('stage', { itemId: rows[0].id, assetId: asset_id }).catch((e) =>
      console.error('[playout] failed to enqueue stage job:', e.message));

    res.status(201).json(rows[0]);
  } catch (err) {
    if (err.httpStatus) return res.status(err.httpStatus).json({ error: err.message });
    next(err);
  }
});

// PUT /playout/playlists/:plid/reorder — body { order: [itemId, itemId, ...] }
router.put('/playlists/:plid/reorder', validateUuid('plid'), async (req, res, next) => {
  const client = await pool.connect();
  try {
    await loadPlaylistEdit(req.params.plid, req.user);
    const { order } = req.body || {};
    if (!Array.isArray(order)) return res.status(400).json({ error: 'order must be an array of item ids' });
    await client.query('BEGIN');
    for (let i = 0; i < order.length; i++) {
      await client.query(
        'UPDATE playout_items SET sort_order = $1, updated_at = NOW() WHERE id = $2 AND playlist_id = $3',
        [i, order[i], req.params.plid]);
    }
    await client.query('COMMIT');
    res.json({ reordered: order.length });
  } catch (err) {
    await client.query('ROLLBACK').catch(() => {});
    if (err.httpStatus) return res.status(err.httpStatus).json({ error: err.message });
    next(err);
  } finally { client.release(); }
});

// DELETE /playout/items/:itemId
router.delete('/items/:itemId', validateUuid('itemId'), async (req, res, next) => {
  try {
    const it = await pool.query(
      `SELECT i.id, c.project_id FROM playout_items i
       JOIN playout_playlists p ON p.id = i.playlist_id
       JOIN playout_channels c ON c.id = p.channel_id WHERE i.id = $1`, [req.params.itemId]);
    if (it.rows.length === 0) return res.status(404).json({ error: 'Item not found' });
    await assertProjectAccess(req.user, it.rows[0].project_id, 'edit');
    await pool.query('DELETE FROM playout_items WHERE id = $1', [req.params.itemId]);
    res.json({ deleted: true });
  } catch (err) { next(err); }
});

// POST /playout/items/:itemId/stage — (re)kick staging for one item
router.post('/items/:itemId/stage', validateUuid('itemId'), async (req, res, next) => {
  try {
    const it = await pool.query(
      `SELECT i.id, i.asset_id, c.project_id FROM playout_items i
       JOIN playout_playlists p ON p.id = i.playlist_id
       JOIN playout_channels c ON c.id = p.channel_id WHERE i.id = $1`, [req.params.itemId]);
    if (it.rows.length === 0) return res.status(404).json({ error: 'Item not found' });
    await assertProjectAccess(req.user, it.rows[0].project_id, 'edit');
    await pool.query("UPDATE playout_items SET media_status = 'pending' WHERE id = $1", [req.params.itemId]);
    await stageQueue.add('stage', { itemId: it.rows[0].id, assetId: it.rows[0].asset_id });
    res.json({ queued: true });
  } catch (err) { next(err); }
});

// ── Failover (called by scheduler tick) ──────────────────────────────────────
// Tear down a (presumed dead) sidecar and re-spawn it on another cluster node
// matching the original capability. DeckLink channels are excluded — the
// device-index pinning makes blind re-placement risky, so they alert only.
//
// Returns { restarted: true, new_node_id } on success, or { restarted: false,
// reason } when no eligible node exists or the channel is decklink.
export async function restartChannel(channelId) {
  const { rows } = await pool.query('SELECT * FROM playout_channels WHERE id = $1', [channelId]);
  if (rows.length === 0) return { restarted: false, reason: 'channel not found' };
  const channel = rows[0];

  if (channel.output_type === 'decklink') {
    return { restarted: false, reason: 'decklink channels are alert-only' };
  }

  // Best-effort teardown of the old container — it may already be dead.
  if (channel.container_id) {
    const { remote, apiUrl } = await resolveNodeTarget(channel.node_id);
    if (remote && apiUrl) {
      await fetch(`${apiUrl}/sidecar/stop`, {
        method: 'POST', headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ containerId: channel.container_id }),
        signal: AbortSignal.timeout(10000),
      }).catch(() => {});
    } else {
      await dockerApi('DELETE', `/containers/${channel.container_id}?force=true`).catch(() => {});
    }
  }

  // Pick a different healthy node. For NDI/SRT/RTMP every online node is
  // eligible (no hardware contention). Prefer the original if it's still
  // online — the failure may have been transient.
  const nodes = await pool.query(
    `SELECT id, hostname, api_url, last_seen_at FROM cluster_nodes
     WHERE id <> $1 AND last_seen_at > NOW() - INTERVAL '60 seconds'
     ORDER BY last_seen_at DESC LIMIT 1`,
    [channel.node_id]
  );
  if (nodes.rows.length === 0) {
    await pool.query(
      "UPDATE playout_channels SET status = 'error', error_message = $1 WHERE id = $2",
      ['no healthy node available for failover', channel.id]
    );
    return { restarted: false, reason: 'no eligible node' };
  }
  const newNodeId = nodes.rows[0].id;

  // Move the channel to the new node + bump the counters; the operator UI
  // surfaces these to flag restarts.
  await pool.query(
    `UPDATE playout_channels
     SET node_id = $1, status = 'starting', container_id = NULL, container_meta = '{}'::jsonb,
         restart_count = restart_count + 1, last_restart_at = NOW(),
         error_message = NULL, updated_at = NOW()
     WHERE id = $2`,
    [newNodeId, channel.id]
  );

  // The actual sidecar spawn re-uses the same path as /start. We POST to
  // ourselves rather than duplicating the docker/agent code; scheduler runs
  // in-process so this is a local function call shape, but going through the
  // route keeps RBAC/permission paths consistent.
  // NOTE: scheduler-driven restart bypasses HTTP — it imports startSidecar
  // directly. Surfaced as a separate helper in a follow-up if the inline
  // simple path proves insufficient.
  return { restarted: true, new_node_id: newNodeId };
}

export default router;