import { spawn, execFileSync } from 'child_process';
import { mkdirSync, writeFileSync } from 'node:fs';
import { dirname } from 'node:path';
import { v4 as uuidv4 } from 'uuid';
import { createUploadStream } from './s3/client.js';

const S3_BUCKET = process.env.S3_BUCKET || 'wild-dragon';

// Growing-files mode: writes the master to a local SMB-backed share that the
// editor can mount, instead of streaming to S3 in real time. The promotion
// worker uploads the finalized file to S3 after the recording stops.
// Toggled per-recorder via `GROWING_ENABLED=true` on the capture container
// (see routes/recorders.js where the env is composed).
const GROWING_ENABLED = process.env.GROWING_ENABLED === 'true';
const GROWING_PATH    = process.env.GROWING_PATH    || '/growing';

// Approach A: when a CIFS source is supplied, this (privileged) container mounts
// the SMB landing-zone share at GROWING_PATH itself, using credentials supplied
// by the API from global Settings. Empty GROWING_SMB_MOUNT → no system mount
// (the host-bound /growing volume is used instead, or S3 streaming if growing
// is off).
// mount.cifs needs a UNC source (//host/share). Operators (and Settings) often
// store the share as an `smb://host/share` URL or a Windows `\\host\share`
// path; the kernel rejects those outright ("Mounting cifs URL not implemented
// yet"), which silently drops us back to S3. Normalize any of these forms to
// the `//host/share` UNC the mount helper accepts.
function toUncShare(raw) {
  if (!raw) return '';
  let s = String(raw).trim().replace(/\\/g, '/');   // \\host\share -> //host/share
  s = s.replace(/^smb:\/\//i, '//');                // smb://host/share -> //host/share
  if (!s.startsWith('//')) s = '//' + s.replace(/^\/+/, '');  // host/share -> //host/share
  return s;
}
const GROWING_SMB_MOUNT    = toUncShare(process.env.GROWING_SMB_MOUNT || '');
const GROWING_SMB_USERNAME = process.env.GROWING_SMB_USERNAME || '';
const GROWING_SMB_PASSWORD = process.env.GROWING_SMB_PASSWORD || '';
const GROWING_SMB_VERS     = process.env.GROWING_SMB_VERS     || '3.0';
const SMB_CREDS_FILE       = '/run/smb-creds';

// True when GROWING_PATH is already a mountpoint (e.g. a prior session left it
// mounted, or a host bind-mount is present).
function isMounted(path) {
  try { execFileSync('mountpoint', ['-q', path]); return true; }
  catch { return false; }
}

// Mount the CIFS growing share at GROWING_PATH. Credentials go in a root-only
// file (NOT the command line) so they never appear in `ps`/process listings.
// Returns true on success (or if already mounted), false on failure — callers
// fall back to S3 streaming so a recording is never lost.
function mountGrowingShare() {
  if (!GROWING_SMB_MOUNT) return false;
  try {
    if (isMounted(GROWING_PATH)) {
      console.log('[capture] growing share already mounted at', GROWING_PATH);
      return true;
    }
    try { mkdirSync(GROWING_PATH, { recursive: true }); } catch (_) {}
    writeFileSync(
      SMB_CREDS_FILE,
      `username=${GROWING_SMB_USERNAME}\npassword=${GROWING_SMB_PASSWORD}\n`,
      { mode: 0o600 }
    );
    const opts = [
      `credentials=${SMB_CREDS_FILE}`,
      'uid=0', 'gid=0', 'file_mode=0664', 'dir_mode=0775',
      `vers=${GROWING_SMB_VERS}`,
    ].join(',');
    execFileSync('mount', ['-t', 'cifs', GROWING_SMB_MOUNT, GROWING_PATH, '-o', opts],
      { stdio: ['ignore', 'ignore', 'pipe'] });
    console.log('[capture] mounted CIFS growing share', GROWING_SMB_MOUNT, '->', GROWING_PATH);
    return true;
  } catch (err) {
    const stderr = err.stderr ? err.stderr.toString().trim() : err.message;
    console.error('[capture] CIFS mount failed (falling back to S3 streaming):', stderr);
    return false;
  }
}

// Best-effort unmount on session stop. Ignores "not mounted".
function unmountGrowingShare() {
  if (!GROWING_SMB_MOUNT) return;
  try {
    if (isMounted(GROWING_PATH)) {
      execFileSync('umount', [GROWING_PATH], { stdio: ['ignore', 'ignore', 'pipe'] });
      console.log('[capture] unmounted growing share at', GROWING_PATH);
    }
  } catch (err) {
    const stderr = err.stderr ? err.stderr.toString().trim() : err.message;
    console.warn('[capture] growing share unmount failed (ignored):', stderr);
  }
}

// ── Codec catalogue ──────────────────────────────────────────────────────
// Each entry maps the UI value to a base ffmpeg flag set. Bitrate / framerate
// / pix_fmt are layered on top from the per-recorder configuration.
const VIDEO_CODECS = {
  prores_hq:    { args: ['-c:v', 'prores_ks', '-profile:v', '3'], bitrateControl: false, pixFmt: 'yuv422p10le' },
  prores_422:   { args: ['-c:v', 'prores_ks', '-profile:v', '2'], bitrateControl: false, pixFmt: 'yuv422p10le' },
  prores_lt:    { args: ['-c:v', 'prores_ks', '-profile:v', '1'], bitrateControl: false, pixFmt: 'yuv422p10le' },
  prores_proxy: { args: ['-c:v', 'prores_ks', '-profile:v', '0'], bitrateControl: false, pixFmt: 'yuv422p10le' },
  dnxhd:        { args: ['-c:v', 'dnxhd'],                          bitrateControl: true,  pixFmt: 'yuv422p' },
  dnxhr_hq:     { args: ['-c:v', 'dnxhd', '-profile:v', 'dnxhr_hq'], bitrateControl: false, pixFmt: 'yuv422p' },
  dnxhr_sq:     { args: ['-c:v', 'dnxhd', '-profile:v', 'dnxhr_sq'], bitrateControl: false, pixFmt: 'yuv422p' },
  h264:         { args: ['-c:v', 'libx264', '-preset', 'medium'],   bitrateControl: true,  pixFmt: 'yuv420p' },
  h264_nvenc:   { args: ['-c:v', 'h264_nvenc', '-preset', 'p5'],    bitrateControl: true,  pixFmt: 'yuv420p' },
  h265:         { args: ['-c:v', 'libx265', '-preset', 'medium'],   bitrateControl: true,  pixFmt: 'yuv420p' },
  // All-Intra HEVC on NVENC — the growing-file master codec.
  // Goal: every frame an IDR (all-intra), so a still-growing file is decodable
  // to its last complete frame — the prerequisite for edit-while-record.
  //
  // NVENC will NOT accept `-g 1`: InitializeEncoder enforces
  // "GopLength > numBFrames + 1", so with -bf 0 the minimum GOP is 2 and -g 1
  // is rejected with EINVAL (validated on the L4, driver 595). The working
  // recipe for true all-intra is therefore:
  //   -bf 0              no B-frames
  //   -g 600             large GOP just to satisfy the init check
  //   -forced-idr 1      forced keyframes are emitted as IDR
  //   -force_key_frames expr:1   force a keyframe on EVERY frame
  // → ffprobe confirms pict_type = I for all frames.
  //
  // Container: fragmented MOV (+frag_keyframe+empty_moov+default_base_moof),
  // NOT MXF — this ffmpeg's MXF muxer rejects HEVC ("Operation not permitted").
  // The frag-MOV index is not deferred to EOF, so the file stays readable while
  // growing. (See docs/design/2026-05-29-all-intra-hevc-ingest.md §8.)
  //
  // -profile:v main10 / p010le: 10-bit 4:2:0 — the closest NVENC HEVC can get
  // to ProRes 4:2:2 10-bit. If strict 4:2:2 is required, use prores_hq (CPU).
  hevc_nvenc:   {
    args: ['-c:v', 'hevc_nvenc', '-preset', 'p4', '-rc', 'vbr', '-bf', '0', '-forced-idr', '1', '-g', '600', '-force_key_frames', 'expr:1', '-profile:v', 'main10'],
    bitrateControl: true,
    pixFmt: 'p010le',
  },
};

const AUDIO_CODECS = {
  pcm_s16le:   { args: ['-c:a', 'pcm_s16le'],   bitrateControl: false },
  pcm_s24le:   { args: ['-c:a', 'pcm_s24le'],   bitrateControl: false },
  pcm_s32le:   { args: ['-c:a', 'pcm_s32le'],   bitrateControl: false },
  aac:         { args: ['-c:a', 'aac'],         bitrateControl: true  },
  ac3:         { args: ['-c:a', 'ac3'],         bitrateControl: true  },
  opus:        { args: ['-c:a', 'libopus'],     bitrateControl: true  },
  flac:        { args: ['-c:a', 'flac'],        bitrateControl: false },
};

const CONTAINER_FMT = {
  mov: 'mov',
  mp4: 'mp4',
  mkv: 'matroska',
  mxf: 'mxf',
  ts:  'mpegts',
};

const CONTAINER_EXT = {
  mov: 'mov', mp4: 'mp4', mkv: 'mkv', mxf: 'mxf', ts: 'ts',
};

function buildEncodeArgs({
  codec, videoBitrate, framerate,
  audioCodec, audioBitrate, audioChannels,
  container, isNetwork, isProxy = false,
}) {
  const v = VIDEO_CODECS[codec] || (isProxy ? VIDEO_CODECS.h264 : VIDEO_CODECS.prores_hq);
  const a = AUDIO_CODECS[audioCodec] || (isProxy ? AUDIO_CODECS.aac : AUDIO_CODECS.pcm_s24le);
  const fmt = CONTAINER_FMT[container] || (isProxy ? 'mp4' : 'mov');

  const args = [];
  if (isNetwork) args.push('-map', '0:v:0?', '-map', '0:a:0?');

  args.push(...v.args);
  if (v.pixFmt) args.push('-pix_fmt', v.pixFmt);
  if (v.bitrateControl && videoBitrate) args.push('-b:v', videoBitrate);
  if (framerate && framerate !== 'native') args.push('-r', framerate);

  args.push(...a.args);
  if (a.bitrateControl && audioBitrate) args.push('-b:a', audioBitrate);
  if (audioChannels) args.push('-ac', String(audioChannels));

  if (fmt === 'mov' || fmt === 'mp4') {
    args.push('-movflags', '+frag_keyframe+empty_moov');
  }
  args.push('-f', fmt);

  return args;
}

class CaptureManager {
  constructor() {
    this.state = {
      recording: false,
      sessionId: null,
      processes: {},
      currentSession: {},
      framesReceived: 0,
      currentFps: 0,
      lastFrameAt: null,
      lastError: null,
    };
  }

  /**
   * Build FFmpeg input arguments based on source type.
   * Returns { inputArgs, isNetwork }
   * @private
   */
  async _buildInputArgs({ sourceType, device, sourceUrl, listen, listenPort, streamKey }) {
    if (sourceType === 'srt') {
      let url;
      if (listen) {
        const port = listenPort || 9000;
        url = `srt://0.0.0.0:${port}?mode=listener`;
      } else {
        url = sourceUrl;
        if (!url.includes('mode=')) {
          url += (url.includes('?') ? '&' : '?') + 'mode=caller';
        }
      }
      return { inputArgs: ['-probesize','32M','-analyzeduration','10M','-fflags','+genpts','-i', url], isNetwork: true };
    }

    if (sourceType === 'rtmp') {
      if (listen) {
        const port = listenPort || 1935;
        const key = streamKey || 'stream';
        return {
          inputArgs: ['-probesize','32M','-analyzeduration','10M','-fflags','+genpts','-listen', '1', '-i', `rtmp://0.0.0.0:${port}/live/${key}`],
          isNetwork: true,
        };
      }
      return { inputArgs: ['-probesize','32M','-analyzeduration','10M','-fflags','+genpts','-i', sourceUrl], isNetwork: true };
    }

    // Deltacast SDI via VideoMaster SDK FFmpeg plugin.
    // FFmpeg input format is 'deltacast', device address is 'deltacast://<index>'.
    // When the physical device is absent (/dev/deltacast<N> missing), fall back
    // to a lavfi test card so development and integration testing work without hardware.
    if (sourceType === 'deltacast') {
      const idx = (typeof device === 'number' || /^\d+$/.test(String(device)))
        ? parseInt(device, 10)
        : 0;
      const { existsSync } = await import('node:fs');
      const deviceNode = `/dev/deltacast${idx}`;
      if (existsSync(deviceNode)) {
        console.log(`[capture] Deltacast index ${idx} → ${deviceNode} (hardware)`);
        return {
          inputArgs: ['-f', 'deltacast', '-i', `deltacast://${idx}`],
          isNetwork: false,
        };
      } else {
        // No hardware — lavfi test card with port label + timecode burn-in.
        // Matches the deltacast-sdi-recorder standalone app fallback exactly so
        // recorded files look right in the MAM library during dev.
        console.warn(`[capture] Deltacast device ${deviceNode} not found — using lavfi test card for port ${idx}`);
        const testSrc = [
          `testsrc2=size=1920x1080:rate=30`,
          `drawtext=text='DELTACAST PORT ${idx} — TEST MODE':fontsize=48:fontcolor=white:x=(w-text_w)/2:y=(h-text_h)/2`,
          `drawtext=text='%{localtime\\:%H\\:%M\\:%S}':fontsize=32:fontcolor=yellow:x=10:y=10`,
        ].join(',');
        return {
          inputArgs: [
            '-f', 'lavfi', '-i', testSrc,
            '-f', 'lavfi', '-i', 'sine=frequency=1000:sample_rate=48000',
            '-map', '0:v:0', '-map', '1:a:0',
          ],
          isNetwork: false,
        };
      }
    }

    // Default: SDI via DeckLink
    // device may be an integer index (0-based) or a full device name string.
    // FFmpeg 7.x DeckLink requires the full name (e.g. 'DeckLink Duo 2 (2)').
    // Map integer index -> name using ffmpeg -sources decklink at runtime.
    //
    // ffmpeg -sources decklink output format:
    //   Auto-detected sources for decklink:
    //     DeckLink Duo 2
    //     DeckLink Duo 2 (2)
    // Lines containing device names start with whitespace; the header line
    // starts with a non-space character. Previous code used a v4l2-style
    // hex-address regex that never matched DeckLink output → index 1+ always
    // fell through to a wrong fallback, producing black output from port 2+.
    let deckLinkName = String(device);
    if (typeof device === 'number' || /^\d+$/.test(String(device))) {
      const idx = parseInt(device, 10);
      try {
        const { execSync } = await import('child_process');
        const out = execSync('ffmpeg -hide_banner -sources decklink 2>&1', { encoding: 'utf-8', timeout: 5000 });
        const names = [];
        for (const line of out.split('\n')) {
          // DeckLink source lines: "  81:76669a80:00000000 [DeckLink Duo (1)] (none)"
          const m = line.match(/^\s+[0-9a-f:]+\s+\[([^\]]+)\]/);
          if (m) names.push(m[1]);
        }
        if (names[idx]) {
          deckLinkName = names[idx];
          console.log(`[capture] DeckLink index ${idx} → "${deckLinkName}" (from ${names.length} detected: ${names.join(', ')})`);
        } else {
          // Fallback: cannot determine model name without enumeration.
          // Log a warning — operator should check the detected device list.
          console.warn(`[capture] DeckLink index ${idx} out of range (detected ${names.length} devices: ${names.join(', ')}). Falling back to index-only input — capture may fail.`);
          deckLinkName = `DeckLink (${idx})`;
        }
      } catch (err) {
        console.warn(`[capture] ffmpeg -sources decklink failed: ${err.message}. Using index ${device} directly.`);
        // Pass the numeric index directly; some ffmpeg builds accept it.
        deckLinkName = String(device);
      }
    }
    return {
      inputArgs: ['-f', 'decklink', '-i', deckLinkName],
      isNetwork: false,
    };
  }

  /**
   * Start a new capture session.
   *
   * Codec parameters all have sensible defaults so legacy callers (no codec
   * args) still produce ProRes HQ master + H.264 proxy.
   */
  async start({
    assetId,
    projectId,
    binId,
    clipName,
    device,
    sourceType = 'sdi',
    sourceUrl,
    listen = false,
    listenPort,
    streamKey,
    // ── Recording codec ─────────────────────────────────────────────
    videoCodec     = 'prores_hq',
    videoBitrate   = null,
    framerate      = null,
    audioCodec     = 'pcm_s24le',
    audioBitrate   = null,
    audioChannels  = 2,
    container      = 'mov',
    // ── Proxy codec ─────────────────────────────────────────────────
    proxyEnabled       = true,
    proxyVideoCodec    = 'h264',
    proxyVideoBitrate  = '8M',
    proxyFramerate     = null,
    proxyAudioCodec    = 'aac',
    proxyAudioBitrate  = '192k',
    proxyAudioChannels = 2,
    proxyContainer     = 'mp4',
  }) {
    this._assetIdForHls = assetId || null;
    if (this.state.recording) {
      throw new Error('Capture already in progress');
    }

    const sessionId = uuidv4();
    const hiresExt  = CONTAINER_EXT[container] || 'mov';
    const proxyExt  = CONTAINER_EXT[proxyContainer] || 'mp4';
    const hiresKey  = `projects/${projectId}/masters/${clipName}.${hiresExt}`;

    // Growing-files: write master to the local SMB share instead of streaming
    // to S3. Path is relative to the container's GROWING_PATH mount.
    //
    // Approach A: if a CIFS source is configured, mount it now. A mount failure
    // is non-fatal — we fall back to S3 streaming so the recording is never
    // lost.
    let growingActive = GROWING_ENABLED;
    if (growingActive && GROWING_SMB_MOUNT) {
      if (!mountGrowingShare()) growingActive = false;  // fall back to S3
    }
    const growingPath = growingActive
      ? `${GROWING_PATH}/${projectId}/${clipName}.${hiresExt}`
      : null;
    if (growingPath) {
      try { mkdirSync(dirname(growingPath), { recursive: true }); }
      catch (err) { console.error('[capture] could not create growing dir:', err.message); }
    }

    // DeckLink hardware does NOT support concurrent capture from the same port.
    // Opening a second ffmpeg process on the same DeckLink input while the first
    // is already capturing causes "Cannot Autodetect input stream or No signal"
    // on the second process — making the proxy empty and potentially crashing the
    // container before the hires upload completes.
    //
    // Treat SDI the same as SRT/RTMP: set proxyKey=null here and let the BullMQ
    // worker generate the proxy from the hires master after the recording stops.
    // The stop handler sets needsProxy=true so the worker picks it up.
    const proxyKey = null;

    const startedAt = new Date().toISOString();

    const { inputArgs, isNetwork } = await this._buildInputArgs({
      sourceType, device, sourceUrl, listen, listenPort, streamKey,
    });

    const hiresCodecArgs = buildEncodeArgs({
      codec: videoCodec, videoBitrate, framerate,
      audioCodec, audioBitrate, audioChannels,
      container,
      isNetwork,
      isProxy: false,
    });

    console.log('[capture] hires ffmpeg args:', hiresCodecArgs.join(' '));

    const sdiFilterArgs = (sourceType === 'sdi') ? ['-vf', 'yadif=mode=1:deint=1'] : [];

    // When growing-files is on, write directly to the SMB share so Premier
    // can mount and edit the live file. Promotion worker uploads to S3 on EOF.
    // Otherwise, stream the master to S3 via stdout pipe (legacy behavior).
    const hiresOutput = growingPath ? growingPath : 'pipe:1';
    const hiresStdio  = growingPath ? ['ignore', 'ignore', 'pipe'] : ['ignore', 'pipe', 'pipe'];

    // For SDI we cannot open the DeckLink device a second time for a preview
    // tee, so the live HLS preview is produced as a SECOND OUTPUT of the hires
    // ffmpeg: one decklink read -> yadif -> split -> [ProRes/S3] + [H.264/HLS].
    let sdiHlsDir = null;
    let hiresArgs;
    if (sourceType === 'sdi' && this._assetIdForHls) {
      const fsMod = await import('node:fs');
      sdiHlsDir = '/live/' + this._assetIdForHls;
      try { fsMod.mkdirSync(sdiHlsDir, { recursive: true }); } catch (_) {}
      hiresArgs = [
        ...inputArgs,
        '-filter_complex', '[0:v]yadif=mode=1:deint=1,split=2[vhi][vlo]',
        // Output 0 — ProRes master (S3 pipe or growing file)
        '-map', '[vhi]', '-map', '0:a:0?',
        ...hiresCodecArgs,
        hiresOutput,
        // Output 1 — low-latency H.264 HLS preview for the UI monitor
        '-map', '[vlo]', '-map', '0:a:0?',
        '-c:v', 'libx264', '-preset', 'veryfast', '-tune', 'zerolatency',
        '-pix_fmt', 'yuv420p', '-b:v', '2M', '-g', '60', '-sc_threshold', '0',
        '-c:a', 'aac', '-b:a', '128k', '-ar', '44100',
        '-f', 'hls', '-hls_time', '2', '-hls_list_size', '15',
        '-hls_flags', 'delete_segments+append_list+omit_endlist',
        '-hls_segment_filename', sdiHlsDir + '/seg-%05d.ts',
        sdiHlsDir + '/index.m3u8',
      ];
      console.log('[HLS] SDI preview as 2nd output -> ' + sdiHlsDir);
    } else {
      hiresArgs = [ ...inputArgs, ...sdiFilterArgs, ...hiresCodecArgs, hiresOutput ];
    }

    const hiresProcess = spawn('ffmpeg', hiresArgs, { stdio: hiresStdio });

    const hiresUpload = growingPath
      ? Promise.resolve({ growingPath })
      : createUploadStream(S3_BUCKET, hiresKey, hiresProcess.stdout);

    const processes = { hires: hiresProcess };
    const uploads = { hires: hiresUpload };

    // ── HLS tee for network sources (live preview in the UI) ──────────
    let hlsProcess = null;
    let hlsDir = null;
    if (isNetwork && this._assetIdForHls) {
      try {
        const fs = await import('node:fs');
        hlsDir = '/live/' + this._assetIdForHls;
        fs.mkdirSync(hlsDir, { recursive: true });
        const hlsArgs = [
          ...inputArgs,
          '-map', '0:v:0?', '-map', '0:a:0?',
          '-c:v', 'libx264', '-preset', 'veryfast', '-tune', 'zerolatency',
          '-pix_fmt', 'yuv420p', '-b:v', '2M', '-g', '60', '-sc_threshold', '0',
          '-c:a', 'aac', '-b:a', '128k', '-ar', '44100',
          '-f', 'hls', '-hls_time', '2', '-hls_list_size', '15',
          '-hls_flags', 'delete_segments+append_list+omit_endlist',
          '-hls_segment_filename', hlsDir + '/seg-%05d.ts',
          hlsDir + '/index.m3u8',
        ];
        hlsProcess = spawn('ffmpeg', hlsArgs, { stdio: ['ignore', 'pipe', 'pipe'] });
        hlsProcess.stderr.on('data', (d) => { console.error('[HLS] ' + d); });
        hlsProcess.on('exit', (c) => console.log('[HLS] exited ' + c));
        processes.hls = hlsProcess;
        console.log('[HLS] tee started -> ' + hlsDir);
      } catch (err) {
        console.error('[HLS] tee failed:', err.message);
      }
    }

    hiresProcess.stderr.on('data', (data) => {
      const text = data.toString();
      console.error(`[HIRES] ${text}`);
      const m = text.match(/frame=\s*(\d+)\s+fps=\s*([\d.]+)/);
      if (m) {
        this.state.framesReceived = parseInt(m[1], 10);
        this.state.currentFps = parseFloat(m[2]);
        this.state.lastFrameAt = new Date().toISOString();
      }
      if (/Connection refused|No route to host|Connection failed|Input\/output error|Server returned|404 Not Found|Connection timed out/i.test(text)) {
        this.state.lastError = text.trim().slice(0, 240);
      }
    });

    // Proxy is generated after stop by the BullMQ worker (same as SRT/RTMP).
    // DeckLink hardware does not support two concurrent readers on the same port.

    this.state.recording = true;
    this.state.sessionId = sessionId;
    this.state.processes = processes;
    this.state.framesReceived = 0;
    this.state.currentFps = 0;
    this.state.lastFrameAt = null;
    this.state.lastError = null;
    this.state.currentSession = {
      sessionId,
      projectId,
      binId,
      clipName,
      device,
      sourceType,
      sourceUrl,
      hiresKey,
      proxyKey,
      growingPath,
      startedAt,
      duration: 0,
      uploads,
      codecs: {
        videoCodec, videoBitrate, framerate,
        audioCodec, audioBitrate, audioChannels, container,
        proxyEnabled, proxyVideoCodec, proxyVideoBitrate,
        proxyAudioCodec, proxyAudioBitrate, proxyAudioChannels, proxyContainer,
      },
    };

    return this._formatSessionResponse();
  }

  async stop(sessionId) {
    if (!this.state.recording || this.state.sessionId !== sessionId) {
      throw new Error('No active capture session or session ID mismatch');
    }

    const { processes, currentSession } = this.state;

    if (processes.hires) processes.hires.kill('SIGINT');
    if (processes.proxy) processes.proxy.kill('SIGINT');
    if (processes.hls)   { try { processes.hls.kill('SIGINT'); } catch (_) {} }

    // Release the CIFS mount (best-effort) once the ffmpeg writers are done with
    // it. The promotion worker reads the staged file from the host/S3 side, not
    // through this container's mount, so unmounting here is safe.
    unmountGrowingShare();

    try {
      const uploadPromises = [currentSession.uploads.hires];
      if (currentSession.uploads.proxy) uploadPromises.push(currentSession.uploads.proxy);
      await Promise.all(uploadPromises);
    } catch (error) {
      console.error('Error during upload completion:', error);
    }

    const stoppedAt = new Date().toISOString();
    const startTime = new Date(currentSession.startedAt);
    const stopTime = new Date(stoppedAt);
    const duration = Math.round((stopTime - startTime) / 1000);

    this.state.recording = false;
    this.state.sessionId = null;
    this.state.processes = {};

    // No frames received → the upload (if any) produced a 0-byte object.
    // Surface that so the shutdown handler can mark the asset as 'error'
    // instead of posting a broken hi-res key downstream.
    const framesReceived = this.state.framesReceived;

    return {
      sessionId,
      projectId: currentSession.projectId,
      binId: currentSession.binId,
      clipName: currentSession.clipName,
      sourceType: currentSession.sourceType,
      hiresKey: currentSession.hiresKey,
      proxyKey: currentSession.proxyKey,
      growingPath: currentSession.growingPath || null,
      startedAt: currentSession.startedAt,
      stoppedAt,
      duration,
      framesReceived,
      empty: framesReceived === 0,
    };
  }

  getStatus() {
    if (!this.state.recording) return { recording: false };

    const startTime = new Date(this.state.currentSession.startedAt);
    const now = new Date();
    const duration = Math.round((now - startTime) / 1000);

    const lastFrameAt = this.state.lastFrameAt;
    const msSinceFrame = lastFrameAt ? (Date.now() - new Date(lastFrameAt).getTime()) : null;
    let signal = 'connecting';
    if (this.state.framesReceived > 0) {
      signal = (msSinceFrame !== null && msSinceFrame < 5000) ? 'receiving' : 'lost';
    } else if (this.state.lastError) {
      signal = 'error';
    }
    return {
      recording: true,
      sessionId: this.state.sessionId,
      sourceType: this.state.currentSession.sourceType,
      device: this.state.currentSession.device,
      clipName: this.state.currentSession.clipName,
      projectId: this.state.currentSession.projectId,
      binId: this.state.currentSession.binId,
      duration,
      startedAt: this.state.currentSession.startedAt,
      signal,
      framesReceived: this.state.framesReceived,
      currentFps: this.state.currentFps,
      lastFrameAt,
      msSinceFrame,
      lastError: this.state.lastError,
      codecs: this.state.currentSession.codecs,
    };
  }

  _formatSessionResponse() {
    const { currentSession, sessionId } = this.state;
    return {
      sessionId,
      projectId: currentSession.projectId,
      binId: currentSession.binId,
      clipName: currentSession.clipName,
      device: currentSession.device,
      sourceType: currentSession.sourceType,
      hiresKey: currentSession.hiresKey,
      proxyKey: currentSession.proxyKey,
      startedAt: currentSession.startedAt,
      codecs: currentSession.codecs,
    };
  }
}

export default new CaptureManager();
export { VIDEO_CODECS, AUDIO_CODECS, CONTAINER_FMT, CONTAINER_EXT };