'use strict';

const path = require('node:path');
const express = require('express');

const { loadConfig } = require('./config');
const { FilestashClient } = require('./filestash');
const { EffectsService } = require('./effects');
const { HomeAssistantClient } = require('./homeassistant');
const { StreamMixer } = require('./streamMixer');
const { createApiRouter } = require('./routes');
const { attachStatusWebSocket } = require('./wsHub');

function buildApp(config) {
  const filestash = new FilestashClient({
    baseUrl: config.filestash.baseUrl,
    shareId: config.filestash.shareId,
  });

  const effects = new EffectsService({
    client: filestash,
    extensions: config.audio.extensions,
    ignoreNames: config.audio.ignoreNames,
    cacheTtlSeconds: config.audio.cacheTtlSeconds,
    maxDepth: config.audio.maxDepth,
  });

  let ha = null;
  if (config.env.haUrl && config.env.haToken) {
    ha = new HomeAssistantClient({
      baseUrl: config.env.haUrl,
      token: config.env.haToken,
      allowedEntity: config.homeAssistant.allowedMediaPlayer,
      timeoutMs: config.homeAssistant.requestTimeoutMs,
    });
  } else {
    // Stub that fails closed so /api/play returns a clear error
    // instead of a server crash when env is incomplete.
    ha = {
      async playMedia() {
        const err = new Error('HA_URL and HA_TOKEN must be set to play media');
        err.status = 503;
        throw err;
      },
      async stop() {
        const err = new Error('HA_URL and HA_TOKEN must be set to stop playback');
        err.status = 503;
        throw err;
      },
    };
  }

  const mixer = new StreamMixer({
    effects,
    localMediaBaseUrl: `http://127.0.0.1:${config.env.port}`,
  });

  const app = express();
  app.disable('x-powered-by');

  // Lightweight CORS: only when ALLOWED_ORIGINS is set.
  if (config.env.allowedOrigins.length) {
    app.use((req, res, next) => {
      const origin = req.headers.origin;
      if (origin && config.env.allowedOrigins.includes(origin)) {
        res.setHeader('Access-Control-Allow-Origin', origin);
        res.setHeader('Vary', 'Origin');
        res.setHeader('Access-Control-Allow-Methods', 'GET,POST,OPTIONS');
        res.setHeader('Access-Control-Allow-Headers', 'Content-Type');
      }
      if (req.method === 'OPTIONS') return res.sendStatus(204);
      next();
    });
  }

  app.use(createApiRouter({ config, effects, filestash, ha, mixer }));

  const publicDir = path.join(__dirname, '..', 'public');
  app.use(express.static(publicDir, { fallthrough: true, index: 'index.html' }));

  // JSON error handler — must keep 4 args for Express to recognize it.
  // eslint-disable-next-line no-unused-vars
  app.use((err, _req, res, _next) => {
    const status = err.status || 500;
    if (status >= 500) {
      // eslint-disable-next-line no-console
      console.error('[error]', err);
    }
    res.status(status).json({ error: err.message || 'internal error' });
  });

  return { app, effects, filestash, mixer };
}

function main() {
  const config = loadConfig();
  const { app, effects, mixer } = buildApp(config);

  const server = app.listen(config.env.port, () => {
    // eslint-disable-next-line no-console
    console.log(`Arcana FX listening on :${config.env.port}`);
    if (!config.env.publicBaseUrl) {
      // eslint-disable-next-line no-console
      console.warn('[warn] PUBLIC_BASE_URL is empty — /api/play will reject until it is set.');
    }
    if (!config.env.haToken) {
      // eslint-disable-next-line no-console
      console.warn('[warn] HA_TOKEN is empty — playback endpoints will return 503.');
    }
  });

  const wsHub = attachStatusWebSocket({
    server,
    mixer,
    entity: config.homeAssistant.allowedMediaPlayer,
  });

  // Warm the cache in the background; ignore failures, they will surface on /api/effects.
  effects.list().catch((err) => {
    // eslint-disable-next-line no-console
    console.warn('[warn] initial effects scan failed:', err.message);
  });

  for (const sig of ['SIGINT', 'SIGTERM']) {
    process.on(sig, () => {
      // eslint-disable-next-line no-console
      console.log(`Received ${sig}, shutting down.`);
      wsHub.close();
      server.close(() => process.exit(0));
      setTimeout(() => process.exit(1), 5000).unref();
    });
  }
}

if (require.main === module) {
  main();
}

module.exports = { buildApp };