const express = require('express');
const router = express.Router();
const { getDB } = require('../database');
const { agentAuth } = require('../middleware/agentAuth');
const { logger } = require('../config/logger');

/**
 * 获取代理佣金记录列表
 * GET /api/commissions
 */
router.get('/', agentAuth, async (req, res) => {
  try {
    const agentId = req.agent.id;
    const { 
      page = 1, 
      limit = 20, 
      search, 
      status,
      commission_type,
      start_date,
      end_date,
      min_amount,
      max_amount,
      sort_by = 'created_at', 
      sort_order = 'desc'
    } = req.query;

    const pageNum = parseInt(page) || 1;
    const limitNum = parseInt(limit) || 20;
    const offset = (pageNum - 1) * limitNum;

    // 构建查询条件
    let whereConditions = ['acr.agent_id = ?'];
    let queryParams = [agentId];

    if (search) {
      whereConditions.push('(u.username LIKE ? OR u.real_name LIKE ? OR u.phone LIKE ?)');
      queryParams.push(`%${search}%`, `%${search}%`, `%${search}%`);
    }

    if (status) {
      whereConditions.push('acr.status = ?');
      queryParams.push(status);
    }

    if (commission_type) {
      whereConditions.push('acr.commission_type = ?');
      queryParams.push(commission_type);
    }

    if (start_date) {
      whereConditions.push('DATE(acr.created_at) >= ?');
      queryParams.push(start_date);
    }

    if (end_date) {
      whereConditions.push('DATE(acr.created_at) <= ?');
      queryParams.push(end_date);
    }

    if (min_amount) {
      whereConditions.push('acr.commission_amount >= ?');
      queryParams.push(parseFloat(min_amount));
    }

    if (max_amount) {
      whereConditions.push('acr.commission_amount <= ?');
      queryParams.push(parseFloat(max_amount));
    }

    const whereClause = whereConditions.join(' AND ');

    // 验证排序字段
    const allowedSortFields = ['created_at', 'commission_amount', 'status', 'commission_type'];
    const sortBy = allowedSortFields.includes(sort_by) ? sort_by : 'created_at';
    const sortOrder = sort_order.toLowerCase() === 'asc' ? 'ASC' : 'DESC';

    // 查询佣金记录列表
    const commissionsQuery = `
      SELECT 
        acr.id,
        acr.agent_id,
        acr.merchant_id,
        acr.commission_type,
        acr.commission_amount,
        acr.status,
        acr.description,
        acr.reference_id,
        acr.created_at,
        acr.updated_at,
        acr.paid_at,
        u.username,
        u.real_name,
        u.phone,
        u.avatar
      FROM agent_commission_records acr
      LEFT JOIN users u ON acr.merchant_id = u.id
      WHERE ${whereClause}
      ORDER BY acr.${sortBy} ${sortOrder}
      LIMIT ${limitNum} OFFSET ${offset}
    `;

    const [commissions] = await getDB().execute(commissionsQuery, queryParams);

    // 查询总数
    const countQuery = `
      SELECT COUNT(*) as total
      FROM agent_commission_records acr
      LEFT JOIN users u ON acr.merchant_id = u.id
      WHERE ${whereClause}
    `;
    
    const [countResult] = await getDB().execute(countQuery, queryParams);
    const total = countResult[0]?.total || 0;

    // 查询统计信息
    const [statsResult] = await getDB().execute(`
      SELECT 
        COUNT(*) as total_commissions,
        COUNT(CASE WHEN status = 'pending' THEN 1 END) as pending_commissions,
        COUNT(CASE WHEN status = 'paid' THEN 1 END) as paid_commissions,
        CAST(COALESCE(SUM(commission_amount), 0) AS DECIMAL(10,2)) as total_amount,
        CAST(COALESCE(SUM(CASE WHEN status = 'pending' THEN commission_amount ELSE 0 END), 0) AS DECIMAL(10,2)) as pending_amount,
        CAST(COALESCE(SUM(CASE WHEN status = 'paid' THEN commission_amount ELSE 0 END), 0) AS DECIMAL(10,2)) as paid_amount,
        CAST(COALESCE(SUM(CASE WHEN DATE(created_at) = CURDATE() THEN commission_amount ELSE 0 END), 0) AS DECIMAL(10,2)) as today_amount
      FROM agent_commission_records
      WHERE agent_id = ?
    `, [agentId]);

    const stats = statsResult[0] || {
      total_commissions: 0,
      pending_commissions: 0,
      paid_commissions: 0,
      total_amount: '0.00',
      pending_amount: '0.00',
      paid_amount: '0.00',
      today_amount: '0.00'
    };

    res.json({
      success: true,
      data: {
        commissions,
        pagination: {
          current_page: pageNum,
          per_page: limitNum,
          total,
          total_pages: Math.ceil(total / limitNum)
        },
        stats
      }
    });

  } catch (error) {
    logger.error('获取佣金记录失败', {
      error: error.message,
      stack: error.stack,
      agentId: req.agent?.id
    });
    
    res.status(500).json({
      success: false,
      message: '获取佣金记录失败'
    });
  }
});

/**
 * 获取单个佣金记录详情
 * GET /api/commissions/:id
 */
router.get('/:id', agentAuth, async (req, res) => {
  try {
    const agentId = req.agent.id;
    const commissionId = req.params.id;

    // 查询佣金记录详情
    const [commissions] = await getDB().execute(`
      SELECT 
        acr.id,
        acr.agent_id,
        acr.merchant_id,
        acr.commission_type,
        acr.commission_amount,
        acr.status,
        acr.description,
        acr.reference_id,
        acr.created_at,
        acr.updated_at,
        acr.paid_at,
        u.username,
        u.real_name,
        u.phone,
        u.avatar,
        u.city,
        u.district
      FROM agent_commission_records acr
      LEFT JOIN users u ON acr.merchant_id = u.id
      WHERE acr.id = ? AND acr.agent_id = ?
    `, [commissionId, agentId]);

    if (commissions.length === 0) {
      return res.status(404).json({
        success: false,
        message: '佣金记录不存在或无权限查看'
      });
    }

    const commission = commissions[0];

    res.json({
      success: true,
      data: commission
    });

  } catch (error) {
    logger.error('获取佣金记录详情失败', {
      error: error.message,
      stack: error.stack,
      agentId: req.agent?.id,
      commissionId: req.params.id
    });
    
    res.status(500).json({
      success: false,
      message: '获取佣金记录详情失败'
    });
  }
});

/**
 * 申请佣金发放（单个）
 * POST /api/commissions/:id/request-payment
 */
router.post('/:id/request-payment', agentAuth, async (req, res) => {
  try {
    const agentId = req.agent.id;
    const commissionId = req.params.id;

    // 检查佣金记录是否存在且属于当前代理
    const [commissions] = await getDB().execute(`
      SELECT id, status, commission_amount
      FROM agent_commission_records
      WHERE id = ? AND agent_id = ?
    `, [commissionId, agentId]);

    if (commissions.length === 0) {
      return res.status(404).json({
        success: false,
        message: '佣金记录不存在或无权限操作'
      });
    }

    const commission = commissions[0];

    if (commission.status !== 'pending') {
      return res.status(400).json({
        success: false,
        message: '只能申请待发放状态的佣金'
      });
    }

    // 更新佣金状态为申请中
    await getDB().execute(`
      UPDATE agent_commission_records 
      SET status = 'requested', updated_at = NOW()
      WHERE id = ?
    `, [commissionId]);

    logger.info('代理申请佣金发放', {
      agentId,
      commissionId,
      amount: commission.commission_amount
    });

    res.json({
      success: true,
      message: '佣金发放申请已提交，请等待审核'
    });

  } catch (error) {
    logger.error('申请佣金发放失败', {
      error: error.message,
      stack: error.stack,
      agentId: req.agent?.id,
      commissionId: req.params.id
    });
    
    res.status(500).json({
      success: false,
      message: '申请佣金发放失败'
    });
  }
});

/**
 * 批量申请佣金发放
 * POST /api/commissions/batch-request-payment
 */
router.post('/batch-request-payment', agentAuth, async (req, res) => {
  try {
    const agentId = req.agent.id;
    const { commission_ids } = req.body;

    if (!commission_ids || !Array.isArray(commission_ids) || commission_ids.length === 0) {
      return res.status(400).json({
        success: false,
        message: '请选择要申请发放的佣金记录'
      });
    }

    // 检查所有佣金记录是否存在且属于当前代理
    const placeholders = commission_ids.map(() => '?').join(',');
    const [commissions] = await getDB().execute(`
      SELECT id, status, commission_amount
      FROM agent_commission_records
      WHERE id IN (${placeholders}) AND agent_id = ?
    `, [...commission_ids, agentId]);

    if (commissions.length !== commission_ids.length) {
      return res.status(400).json({
        success: false,
        message: '部分佣金记录不存在或无权限操作'
      });
    }

    // 检查状态
    const invalidCommissions = commissions.filter(c => c.status !== 'pending');
    if (invalidCommissions.length > 0) {
      return res.status(400).json({
        success: false,
        message: '只能申请待发放状态的佣金'
      });
    }

    // 批量更新状态
    await getDB().execute(`
      UPDATE agent_commission_records 
      SET status = 'requested', updated_at = NOW()
      WHERE id IN (${placeholders}) AND agent_id = ?
    `, [...commission_ids, agentId]);

    const totalAmount = commissions.reduce((sum, c) => sum + parseFloat(c.commission_amount), 0);

    logger.info('代理批量申请佣金发放', {
      agentId,
      commissionIds: commission_ids,
      count: commission_ids.length,
      totalAmount
    });

    res.json({
      success: true,
      message: `已提交${commission_ids.length}条佣金发放申请，总金额${totalAmount.toFixed(2)}元`
    });

  } catch (error) {
    logger.error('批量申请佣金发放失败', {
      error: error.message,
      stack: error.stack,
      agentId: req.agent?.id
    });
    
    res.status(500).json({
      success: false,
      message: '批量申请佣金发放失败'
    });
  }
});

/**
 * 获取佣金趋势数据
 * GET /api/commissions/trend
 */
router.get('/trend/data', agentAuth, async (req, res) => {
  try {
    const agentId = req.agent.id;
    const { days = 7, type = 'amount' } = req.query;

    let selectField = 'CAST(COALESCE(SUM(commission_amount), 0) AS DECIMAL(10,2)) as value';
    if (type === 'count') {
      selectField = 'COUNT(*) as value';
    }

    const [trendData] = await getDB().execute(`
      SELECT 
        DATE(created_at) as date,
        ${selectField}
      FROM agent_commission_records
      WHERE agent_id = ?
        AND created_at >= DATE_SUB(CURDATE(), INTERVAL ? DAY)
      GROUP BY DATE(created_at)
      ORDER BY date ASC
    `, [agentId, parseInt(days)]);

    res.json({
      success: true,
      data: trendData
    });

  } catch (error) {
    logger.error('获取佣金趋势失败', {
      error: error.message,
      stack: error.stack,
      agentId: req.agent?.id
    });
    
    res.status(500).json({
      success: false,
      message: '获取佣金趋势失败'
    });
  }
});

/**
 * 导出佣金记录
 * GET /api/commissions/export
 */
router.get('/export/data', agentAuth, async (req, res) => {
  try {
    const agentId = req.agent.id;
    const { 
      format = 'json', 
      search, 
      status, 
      commission_type, 
      start_date, 
      end_date,
      min_amount,
      max_amount
    } = req.query;

    // 构建查询条件
    let whereConditions = ['acr.agent_id = ?'];
    let queryParams = [agentId];

    if (search) {
      whereConditions.push('(u.username LIKE ? OR u.real_name LIKE ? OR u.phone LIKE ?)');
      queryParams.push(`%${search}%`, `%${search}%`, `%${search}%`);
    }

    if (status) {
      whereConditions.push('acr.status = ?');
      queryParams.push(status);
    }

    if (commission_type) {
      whereConditions.push('acr.commission_type = ?');
      queryParams.push(commission_type);
    }

    if (start_date) {
      whereConditions.push('DATE(acr.created_at) >= ?');
      queryParams.push(start_date);
    }

    if (end_date) {
      whereConditions.push('DATE(acr.created_at) <= ?');
      queryParams.push(end_date);
    }

    if (min_amount) {
      whereConditions.push('acr.commission_amount >= ?');
      queryParams.push(parseFloat(min_amount));
    }

    if (max_amount) {
      whereConditions.push('acr.commission_amount <= ?');
      queryParams.push(parseFloat(max_amount));
    }

    const whereClause = whereConditions.join(' AND ');

    // 查询佣金记录
    const [commissions] = await getDB().execute(`
      SELECT 
        acr.id,
        acr.commission_type,
        acr.commission_amount,
        acr.status,
        acr.description,
        acr.reference_id,
        acr.created_at,
        acr.paid_at,
        u.username,
        u.real_name,
        u.phone
      FROM agent_commission_records acr
      LEFT JOIN users u ON acr.merchant_id = u.id
      WHERE ${whereClause}
      ORDER BY acr.created_at DESC
    `, queryParams);

    if (format === 'csv') {
      // 生成CSV格式
      const csvHeader = 'ID,佣金类型,佣金金额,状态,描述,关联ID,用户名,真实姓名,手机号,创建时间,发放时间\n';
      const csvData = commissions.map(commission => {
        return [
          commission.id,
          commission.commission_type || '',
          commission.commission_amount,
          commission.status || '',
          (commission.description || '').replace(/,/g, '，'), // 替换逗号避免CSV格式问题
          commission.reference_id || '',
          commission.username || '',
          commission.real_name || '',
          commission.phone || '',
          commission.created_at || '',
          commission.paid_at || ''
        ].join(',');
      }).join('\n');

      res.setHeader('Content-Type', 'text/csv; charset=utf-8');
      res.setHeader('Content-Disposition', `attachment; filename="commissions_${Date.now()}.csv"`);
      res.send(csvHeader + csvData);
    } else {
      // 默认JSON格式
      res.json({
        success: true,
        data: commissions,
        exported_at: new Date().toISOString(),
        total: commissions.length
      });
    }

  } catch (error) {
    logger.error('导出佣金记录失败', {
      error: error.message,
      stack: error.stack,
      agentId: req.agent?.id
    });
    
    res.status(500).json({
      success: false,
      message: '导出佣金记录失败'
    });
  }
});

module.exports = router;