const express = require('express');
const rateLimit = require('express-rate-limit');
const { ChannelType } = require('discord.js');
const { CONFIG } = require('../config');
const { safeEqual } = require('../utils');
const { applyConfigUpdates, readAllConfig } = require('../services/configPersistence');
const { logSystem } = require('../services/debugLog');
const { REGISTRY: NOTIFICATION_REGISTRY } = require('../services/notificationRegistry');
const { ALLOWED_CONFIG_KEYS } = require('../services/configSchema');
const {
  getAllState: getNotificationState,
  setKeyEnabled,
  setCategoryEnabled,
  setMasterEnabled
} = require('../services/notificationEnabled');

const router = express.Router();

// Intentionally no trust-proxy: loopback-only; global rate-limit bucket.
const internalLimiter = rateLimit({
  windowMs: 60 * 1000,
  max: 10,
  standardHeaders: true,
  legacyHeaders: false,
  message: { error: 'Too many requests, please try again later.' }
});

router.use(internalLimiter);

// Middleware: verify internal secret
router.use((req, res, next) => {
  const secret = req.headers['x-internal-secret'];
  if (!CONFIG.INTERNAL_API_SECRET || !safeEqual(secret, CONFIG.INTERNAL_API_SECRET)) {
    return res.status(401).json({ error: 'Unauthorized' });
  }
  next();
});

// GET /config — return all current .env values (redacted secrets)
router.get('/config', (req, res) => {
  const map = readAllConfig();
  const obj = {};
  const REDACTED = ['DISCORD_TOKEN', 'REFRESH_TOKEN', 'GOOGLE_CLIENT_SECRET', 'MONGODB_URI', 'INTERNAL_API_SECRET', 'SETTINGS_ADMIN_PASSWORD'];
  for (const [k, v] of map) {
    obj[k] = REDACTED.includes(k) ? '••••••••' : v;
  }
  res.json(obj);
});

// POST /config — apply config updates. ALLOWED_CONFIG_KEYS comes from
// services/configSchema (the canonical schema + allowlist).
router.post('/config', express.json(), async (req, res) => {
  const updates = req.body;
  if (!updates || typeof updates !== 'object' || Array.isArray(updates)) {
    return res.status(400).json({ error: 'Invalid body' });
  }
  const rejected = Object.keys(updates).filter(k => !ALLOWED_CONFIG_KEYS.has(k));
  if (rejected.length > 0) {
    return res.status(400).json({ error: `Disallowed config keys: ${rejected.join(', ')}` });
  }
  const result = applyConfigUpdates(updates);
  const errorSummary = result.errors.map(e => `${e.key}: ${e.error}`).join(', ');
  await logSystem('Config updated via settings UI', [
    { name: 'Keys updated', value: result.applied.join(', ') || 'none', inline: false },
    { name: 'Errors', value: errorSummary || 'none', inline: false }
  ]).catch(() => {});
  // Partial success stays 200 so the client can still apply the successful keys.
  // Only 400 when every submitted key failed validation (i.e. the save did nothing).
  const totalSubmitted = Object.keys(updates).length;
  const allFailed = totalSubmitted > 0 && result.applied.length === 0 && result.errors.length > 0;
  res.status(allFailed ? 400 : 200).json(result);
});

// GET /discord/guild — return guild info for smart dropdowns
router.get('/discord/guild', async (req, res) => {
  try {
    const client = require('../api/bosscordClient').getBot();
    if (!client) return res.status(503).json({ error: 'Bot not ready' });

    const guild = client.guilds.cache.get(CONFIG.DISCORD_GUILD_ID);
    if (!guild) return res.status(404).json({ error: 'Guild not found' });

    await guild.members.fetch().catch(() => {});

    const CHANNEL_TYPES = [
      ChannelType.GuildText,
      ChannelType.GuildCategory,
      ChannelType.GuildAnnouncement,
      ChannelType.GuildForum
    ];
    const channels = guild.channels.cache
      .filter(c => CHANNEL_TYPES.includes(c.type))
      .map(c => ({ id: c.id, name: c.name, type: c.type, parentId: c.parentId }))
      .sort((a, b) => a.name.localeCompare(b.name));

    const roles = guild.roles.cache
      .filter(r => !r.managed && r.id !== guild.id)
      .map(r => ({ id: r.id, name: r.name, color: r.hexColor }))
      .sort((a, b) => b.position - a.position);

    const members = guild.members.cache
      .filter(m => !m.user.bot)
      .map(m => ({
        id: m.id,
        username: m.user.username,
        displayName: m.displayName,
        avatar: m.user.displayAvatarURL({ size: 32 })
      }))
      .sort((a, b) => a.displayName.localeCompare(b.displayName));

    const categories = guild.channels.cache
      .filter(c => c.type === ChannelType.GuildCategory)
      .map(c => ({ id: c.id, name: c.name }))
      .sort((a, b) => a.name.localeCompare(b.name));

    res.json({ channels, roles, members, categories });
  } catch (err) {
    res.status(500).json({ error: err.message });
  }
});

// POST /restart — restart the bot process
let scheduledRestart = null;

router.post('/restart', express.json(), (req, res) => {
  const { mode, scheduledFor } = req.body;

  if (mode === 'immediate') {
    res.json({ ok: true, mode });
    setTimeout(() => {
      console.log('[restart] Restarting bot process...');
      process.exit(0); // Docker/systemd will restart
    }, 1500);
    return;
  }

  if (mode === 'scheduled' && scheduledFor) {
    const delay = new Date(scheduledFor).getTime() - Date.now();
    if (delay <= 0) return res.status(400).json({ error: 'Scheduled time is in the past' });
    if (scheduledRestart) clearTimeout(scheduledRestart);
    // Lazy require: broccolini-discord.js requires this file at module scope before its exports are populated.
    const { trackTimeout } = require('../broccolini-discord');
    scheduledRestart = trackTimeout(setTimeout(() => {
      console.log('[restart] Scheduled restart firing...');
      process.exit(0);
    }, delay));
    if (scheduledRestart && typeof scheduledRestart.unref === 'function') scheduledRestart.unref();
    res.json({ ok: true, mode, scheduledFor, delayMs: delay });
    return;
  }

  if (mode === 'cancel_scheduled') {
    if (scheduledRestart) { clearTimeout(scheduledRestart); scheduledRestart = null; }
    res.json({ ok: true, cancelled: true });
    return;
  }

  if (mode === 'pending') {
    res.json({ ok: true, mode: 'pending', note: 'Restart required on next manual restart' });
    return;
  }

  res.status(400).json({ error: 'Invalid mode' });
});

router.get('/restart/status', (req, res) => {
  res.json({ scheduledRestart: !!scheduledRestart });
});

// GET /notifications/alerts — canonical bot-side notification alert catalog
router.get('/notifications/alerts', (req, res) => {
  res.json(NOTIFICATION_REGISTRY);
});

// GET /notifications/state — Phase 9: master flag + per-key enable map
router.get('/notifications/state', (req, res) => {
  res.json(getNotificationState());
});

// POST /notifications/toggle — Phase 9: mutate one of {master, category, key}
//
// Body shapes (exactly one of these must be used):
//   { master:   true, enabled: <bool> }
//   { category: <str>, enabled: <bool> }
//   { key:      <str>, enabled: <bool> }
//
// Mutates CONFIG in memory via notificationEnabled, then persists through
// applyConfigUpdates so the value passes schema validation and ends up in .env.
router.post('/notifications/toggle', express.json(), async (req, res) => {
  const body = req.body;
  if (!body || typeof body !== 'object' || Array.isArray(body)) {
    return res.status(400).json({ error: 'Invalid body' });
  }
  if (typeof body.enabled !== 'boolean') {
    return res.status(400).json({ error: '`enabled` must be boolean' });
  }

  const hasMaster = Object.prototype.hasOwnProperty.call(body, 'master');
  const hasCategory = Object.prototype.hasOwnProperty.call(body, 'category');
  const hasKey = Object.prototype.hasOwnProperty.call(body, 'key');
  const specifiedCount = Number(hasMaster) + Number(hasCategory) + Number(hasKey);
  if (specifiedCount !== 1) {
    return res.status(400).json({ error: 'Specify exactly one of: master, category, key' });
  }

  let updates;
  if (hasMaster) {
    setMasterEnabled(body.enabled);
    updates = { NOTIFICATIONS_MASTER_ENABLED: body.enabled };
  } else if (hasCategory) {
    if (typeof body.category !== 'string' || !Object.prototype.hasOwnProperty.call(NOTIFICATION_REGISTRY, body.category)) {
      return res.status(400).json({ error: 'Unknown category' });
    }
    const newJson = setCategoryEnabled(body.category, body.enabled);
    updates = { NOTIFICATION_ENABLED_JSON: newJson };
  } else {
    if (typeof body.key !== 'string' || !body.key) {
      return res.status(400).json({ error: '`key` must be a non-empty string' });
    }
    const newJson = setKeyEnabled(body.key, body.enabled);
    updates = { NOTIFICATION_ENABLED_JSON: newJson };
  }

  const result = applyConfigUpdates(updates);
  if (result.errors.length > 0) {
    return res.status(500).json({ error: 'Persistence failed', details: result.errors });
  }
  res.json({ state: getNotificationState() });
});

// POST /gmail/reload — hot-swap Gmail OAuth creds after weekly reauth without
// restarting the process. Reads REFRESH_TOKEN from .env via configPersistence,
// probes Google with users.getProfile, and on success clears pollSuspended and
// re-installs the poll interval. On failure returns 400 with Google's error so
// the operator can see why (e.g. still invalid_grant).
router.post('/gmail/reload', express.json(), async (req, res) => {
  const { reloadGmailClient } = require('../services/gmail');
  const { setPollSuspended } = require('../gmail-poll');
  try {
    const { emailAddress } = await reloadGmailClient();
    setPollSuspended(false);
    // Lazy require — same reason as /restart above (module scope cycle).
    const parent = require('../broccolini-discord');
    if (parent.setGmailPollInterval) {
      parent.setGmailPollInterval(CONFIG.GMAIL_POLL_INTERVAL_MS);
    }
    await logSystem('Gmail OAuth reloaded', [
      { name: 'Account', value: emailAddress, inline: false }
    ]).catch(() => {});
    res.json({ ok: true, email: emailAddress });
  } catch (err) {
    const oauthError = err && err.response && err.response.data && err.response.data.error;
    res.status(400).json({
      ok: false,
      error: oauthError || err.code || err.message || 'reload failed'
    });
  }
});

// Expose the allowlist for the Phase 8 schema smoke test. Attached to the
// router function object; doesn't show up as a route.
router._allowedKeys = Array.from(ALLOWED_CONFIG_KEYS);

module.exports = router;