import { loadWechatMpConfig } from './wechat-mp.mjs';
import { nextDailyRunAt, normalizeTimezone } from './schedule-time.mjs';

const DEFAULT_LIMIT = 50;
const MAX_LIMIT = 200;

function clampLimit(value) {
  const parsed = Number(value);
  if (!Number.isFinite(parsed) || parsed <= 0) return DEFAULT_LIMIT;
  return Math.min(Math.floor(parsed), MAX_LIMIT);
}

function normalizeStatus(value, allowed) {
  const status = typeof value === 'string' ? value.trim() : '';
  return allowed.includes(status) ? status : null;
}

function likePattern(value) {
  const text = typeof value === 'string' ? value.trim() : '';
  return text ? `%${text}%` : null;
}

export function maskWechatId(value) {
  const text = String(value ?? '');
  if (text.length <= 8) return text ? '***' : '';
  return `${text.slice(0, 6)}...${text.slice(-4)}`;
}

function maskAppId(value) {
  const text = String(value ?? '');
  if (text.length <= 10) return text || null;
  return `${text.slice(0, 6)}...${text.slice(-4)}`;
}

function boolFromEnv(value) {
  return value === true || value === '1' || value === 'true';
}

function mapBindingRow(row) {
  return {
    userId: row.user_id,
    username: row.username,
    displayName: row.display_name,
    status: row.status,
    appId: maskAppId(row.app_id),
    openidMasked: maskWechatId(row.openid),
    nickname: row.nickname,
    avatarUrl: row.avatar_url,
    lastLoginAt: Number(row.last_login_at ?? 0),
    boundAt: Number(row.bound_at ?? 0),
    routeId: row.route_id,
    routeStatus: row.route_status,
    agentSessionId: row.agent_session_id,
    routeUpdatedAt: row.route_updated_at ? Number(row.route_updated_at) : null,
  };
}

function mapMessageRow(row) {
  return {
    appId: maskAppId(row.app_id),
    openidMasked: maskWechatId(row.openid),
    msgId: row.msg_id,
    status: row.status,
    agentSessionId: row.agent_session_id,
    createdAt: Number(row.created_at ?? 0),
    updatedAt: Number(row.updated_at ?? 0),
    userId: row.user_id,
    username: row.username,
    displayName: row.display_name,
  };
}

function mapDigestRow(row) {
  return {
    id: row.id,
    userId: row.user_id,
    username: row.username,
    displayName: row.display_name,
    digestType: row.digest_type,
    hour: Number(row.hour),
    minute: Number(row.minute),
    timezone: row.timezone,
    channel: row.channel,
    status: row.status,
    nextRunAt: Number(row.next_run_at ?? 0),
    lastRunAt: row.last_run_at ? Number(row.last_run_at) : null,
    attempts: Number(row.attempts ?? 0),
    lastError: row.last_error,
    sourceText: row.source_text,
    createdAt: Number(row.created_at ?? 0),
    updatedAt: Number(row.updated_at ?? 0),
  };
}

function mapDeliveryRow(row) {
  return {
    id: row.id,
    reminderId: row.reminder_id,
    subscriptionId: row.subscription_id,
    userId: row.user_id,
    username: row.username,
    displayName: row.display_name,
    channel: row.channel,
    status: row.status,
    providerMessageId: row.provider_message_id,
    errorCode: row.error_code,
    errorMessage: row.error_message,
    createdAt: Number(row.created_at ?? 0),
    digestType: row.digest_type,
  };
}

export function createWechatAdminService(
  pool,
  {
    config = loadWechatMpConfig(),
    scheduleEnabled = boolFromEnv(process.env.H5_SCHEDULE_ENABLED),
    reminderWorkerEnabled = boolFromEnv(process.env.H5_REMINDER_WORKER_ENABLED),
  } = {},
) {
  async function getSummary() {
    const now = Date.now();
    const recentSince = now - 24 * 60 * 60 * 1000;
    const [[identityRows], [routeRows], [messageRows], [digestRows], [deliveryRows]] =
      await Promise.all([
        pool.query('SELECT COUNT(*) AS count FROM h5_user_wechat_identities'),
        pool.query(
          `SELECT
             COUNT(*) AS total,
             SUM(CASE WHEN status = 'active' THEN 1 ELSE 0 END) AS active
           FROM h5_wechat_agent_routes`,
        ),
        pool.query(
          `SELECT status, COUNT(*) AS count
           FROM h5_wechat_mp_messages
           WHERE updated_at >= ?
           GROUP BY status`,
          [recentSince],
        ),
        pool.query(
          `SELECT status, COUNT(*) AS count
           FROM h5_schedule_digest_subscriptions
           GROUP BY status`,
        ),
        pool.query(
          `SELECT status, COUNT(*) AS count
           FROM h5_schedule_delivery_logs
           WHERE created_at >= ?
           GROUP BY status`,
          [recentSince],
        ),
      ]);

    return {
      config: {
        mpEnabled: Boolean(config?.enabled),
        scheduleEnabled,
        reminderWorkerEnabled,
        appId: maskAppId(config?.appId),
        publicBaseUrl: config?.publicBaseUrl ?? null,
        bindPath: config?.bindPath ?? null,
        tokenEndpointConfigured: Boolean(config?.tokenUrl),
        customerServiceEndpointConfigured: Boolean(config?.customerServiceUrl),
      },
      counts: {
        boundUsers: Number(identityRows[0]?.count ?? 0),
        routes: {
          total: Number(routeRows[0]?.total ?? 0),
          active: Number(routeRows[0]?.active ?? 0),
        },
        recentMessages: Object.fromEntries(
          messageRows.map((row) => [row.status, Number(row.count ?? 0)]),
        ),
        digests: Object.fromEntries(digestRows.map((row) => [row.status, Number(row.count ?? 0)])),
        recentDeliveries: Object.fromEntries(
          deliveryRows.map((row) => [row.status, Number(row.count ?? 0)]),
        ),
      },
    };
  }

  async function listBindings({ search, limit } = {}) {
    const values = [];
    const where = [];
    const pattern = likePattern(search);
    if (pattern) {
      where.push(
        `(u.username LIKE ? OR u.display_name LIKE ? OR wi.nickname LIKE ? OR wi.openid LIKE ?)`,
      );
      values.push(pattern, pattern, pattern, pattern);
    }
    values.push(clampLimit(limit));
    const [rows] = await pool.query(
      `SELECT
         wi.user_id, wi.app_id, wi.openid, wi.nickname, wi.avatar_url,
         wi.last_login_at, wi.created_at AS bound_at,
         u.username, u.display_name, u.status,
         r.id AS route_id, r.status AS route_status, r.agent_session_id,
         r.updated_at AS route_updated_at
       FROM h5_user_wechat_identities wi
       JOIN h5_users u ON u.id = wi.user_id
       LEFT JOIN h5_wechat_agent_routes r ON r.app_id = wi.app_id AND r.openid = wi.openid
       ${where.length ? `WHERE ${where.join(' AND ')}` : ''}
       ORDER BY wi.updated_at DESC
       LIMIT ?`,
      values,
    );
    return { bindings: rows.map(mapBindingRow) };
  }

  async function listMessages({ status, limit } = {}) {
    const values = [];
    const where = [];
    const normalizedStatus = normalizeStatus(status, ['processing', 'done', 'failed']);
    if (normalizedStatus) {
      where.push('m.status = ?');
      values.push(normalizedStatus);
    }
    values.push(clampLimit(limit));
    const [rows] = await pool.query(
      `SELECT
         m.app_id, m.openid, m.msg_id, m.status, m.agent_session_id,
         m.created_at, m.updated_at,
         wi.user_id, u.username, u.display_name
       FROM h5_wechat_mp_messages m
       LEFT JOIN h5_user_wechat_identities wi ON wi.app_id = m.app_id AND wi.openid = m.openid
       LEFT JOIN h5_users u ON u.id = wi.user_id
       ${where.length ? `WHERE ${where.join(' AND ')}` : ''}
       ORDER BY m.updated_at DESC
       LIMIT ?`,
      values,
    );
    return { messages: rows.map(mapMessageRow) };
  }

  async function listDigests({ status, limit } = {}) {
    const values = [];
    const where = [];
    const normalizedStatus = normalizeStatus(status, ['active', 'locked', 'failed', 'cancelled']);
    if (normalizedStatus) {
      where.push('s.status = ?');
      values.push(normalizedStatus);
    }
    values.push(clampLimit(limit));
    const [rows] = await pool.query(
      `SELECT
         s.*, u.username, u.display_name
       FROM h5_schedule_digest_subscriptions s
       JOIN h5_users u ON u.id = s.user_id
       ${where.length ? `WHERE ${where.join(' AND ')}` : ''}
       ORDER BY s.updated_at DESC
       LIMIT ?`,
      values,
    );
    return { digests: rows.map(mapDigestRow) };
  }

  async function listDeliveries({ status, limit } = {}) {
    const values = [];
    const where = [];
    const normalizedStatus = normalizeStatus(status, ['success', 'failed']);
    if (normalizedStatus) {
      where.push('d.status = ?');
      values.push(normalizedStatus);
    }
    values.push(clampLimit(limit));
    const [rows] = await pool.query(
      `SELECT
         d.*, u.username, u.display_name, s.digest_type
       FROM h5_schedule_delivery_logs d
       JOIN h5_users u ON u.id = d.user_id
       LEFT JOIN h5_schedule_digest_subscriptions s ON s.id = d.subscription_id
       ${where.length ? `WHERE ${where.join(' AND ')}` : ''}
       ORDER BY d.created_at DESC
       LIMIT ?`,
      values,
    );
    return { deliveries: rows.map(mapDeliveryRow) };
  }

  async function clearRouteForUser(userId) {
    const [rows] = await pool.query(
      `SELECT app_id, openid
       FROM h5_user_wechat_identities
       WHERE user_id = ?
       ORDER BY updated_at DESC
       LIMIT 1`,
      [userId],
    );
    const identity = rows[0];
    if (!identity) return { ok: false, message: '用户未绑定服务号' };
    const [result] = await pool.query(
      `DELETE FROM h5_wechat_agent_routes
       WHERE app_id = ? AND openid = ?`,
      [identity.app_id, identity.openid],
    );
    return {
      ok: true,
      deleted: Number(result.affectedRows ?? 0),
      openidMasked: maskWechatId(identity.openid),
    };
  }

  async function cancelDigest(id) {
    const now = Date.now();
    const [result] = await pool.query(
      `UPDATE h5_schedule_digest_subscriptions
       SET status = 'cancelled', locked_until = NULL, updated_at = ?
       WHERE id = ? AND status <> 'cancelled'`,
      [now, id],
    );
    return { ok: Number(result.affectedRows ?? 0) > 0 };
  }

  async function resumeDigest(id) {
    const [rows] = await pool.query(
      `SELECT id, hour, minute, timezone
       FROM h5_schedule_digest_subscriptions
       WHERE id = ?
       LIMIT 1`,
      [id],
    );
    const digest = rows[0];
    if (!digest) return { ok: false, message: '订阅不存在' };
    const timezone = normalizeTimezone(digest.timezone);
    const now = Date.now();
    const nextRun = nextDailyRunAt({
      hour: Number(digest.hour),
      minute: Number(digest.minute),
      timezone,
      now,
    });
    await pool.query(
      `UPDATE h5_schedule_digest_subscriptions
       SET status = 'active', next_run_at = ?, attempts = 0, locked_until = NULL,
           last_error = NULL, timezone = ?, updated_at = ?
       WHERE id = ?`,
      [nextRun, timezone, now, id],
    );
    return { ok: true, nextRunAt: nextRun };
  }

  return {
    getSummary,
    listBindings,
    listMessages,
    listDigests,
    listDeliveries,
    clearRouteForUser,
    cancelDigest,
    resumeDigest,
  };
}