const express = require('express');
const db = require('../db');
const config = require('../config');
const logger = require('../utils/logger');
const {
  getMonthRange,
  AppError,
  validateRequired,
  validateNumber,
  validateInList,
  validatePage,
  validateLimit,
  validateIsoDate,
  optionalString
} = require('../utils/helpers');

const router = express.Router();

// 新增记录
router.post('/', (req, res, next) => {
  try {
    const { type, category, amount, quantity, unit_price, rebate, boss, partner, source, destination, note, created_at } = req.body;

    // 输入验证
    validateRequired(req.body, ['type', 'category', 'amount']);
    validateInList(type, 'type', ['income', 'expense']);

    const allCategories = [...config.categories.income, ...config.categories.expense];
    validateInList(category, 'category', allCategories);

    // 派单的返点可为负数，因此金额也允许为负数
    const validatedAmount = category === '派单'
      ? validateNumber(amount, '金额')
      : validateNumber(amount, '金额', 0);
    const validatedQuantity = quantity === undefined || quantity === null || quantity === '' ? null : validateNumber(quantity, '数量', 0);
    const validatedUnitPrice = unit_price === undefined || unit_price === null || unit_price === '' ? null : validateNumber(unit_price, '单价', 0);
    const validatedRebate = rebate === undefined || rebate === null || rebate === '' ? null : validateNumber(rebate, '返点');
    const validatedCreatedAt = validateIsoDate(created_at, '创建时间');

    const stmt = db.prepare(`
      INSERT INTO records (user_id, type, category, amount, quantity, unit_price, rebate, boss, partner, source, destination, note, created_at)
      VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
    `);
    const result = stmt.run(
      req.user.id,
      type,
      category,
      validatedAmount,
      validatedQuantity,
      validatedUnitPrice,
      validatedRebate,
      optionalString(boss, '老板', 100),
      optionalString(partner, '陪玩', 100),
      optionalString(source, '来源', 100),
      optionalString(destination, '去向', 100),
      optionalString(note, '备注', 500),
      validatedCreatedAt
    );

    logger.info(`用户 ${req.user.username} 新增记录: ${category} ${validatedAmount}`);
    res.json({ id: result.lastInsertRowid });
  } catch (err) {
    next(err);
  }
});

// 通用分页查询函数
function queryPagedRecords(userId, year, month, options) {
  const page = validatePage(options.page, 1);
  const limit = validateLimit(options.limit, config.pagination.defaultLimit, config.pagination.maxLimit);
  const offset = (page - 1) * limit;
  const { startDate, endDate } = getMonthRange(year, month);

  let whereClause = `user_id = ? AND DATE(created_at, 'localtime') >= ? AND DATE(created_at, 'localtime') < ?`;
  const params = [userId, startDate, endDate];

  if (options.category) {
    whereClause += ` AND category = ?`;
    params.push(options.category);
  }
  if (options.type) {
    whereClause += ` AND type = ?`;
    params.push(options.type);
  }
  if (options.excludeCategories && options.excludeCategories.length > 0) {
    whereClause += ` AND category NOT IN (${options.excludeCategories.map(() => '?').join(',')})`;
    params.push(...options.excludeCategories);
  }

  const total = db.prepare(
    `SELECT COUNT(*) as count FROM records WHERE ${whereClause}`
  ).get(...params).count;

  const records = db.prepare(
    `SELECT * FROM records WHERE ${whereClause} ORDER BY created_at DESC LIMIT ? OFFSET ?`
  ).all(...params, limit, offset);

  return { records, total, page, limit };
}

// 接单列表
router.get('/orders', (req, res) => {
  const result = queryPagedRecords(req.user.id, req.query.year, req.query.month, {
    category: '接单',
    page: req.query.page,
    limit: req.query.limit
  });
  res.json(result);
});

// 红包及其他收入列表
router.get('/other-income', (req, res) => {
  const result = queryPagedRecords(req.user.id, req.query.year, req.query.month, {
    type: 'income',
    excludeCategories: ['接单', '派单'],
    page: req.query.page,
    limit: req.query.limit
  });
  res.json(result);
});

// 红包收入列表
router.get('/red-envelope', (req, res) => {
  const result = queryPagedRecords(req.user.id, req.query.year, req.query.month, {
    type: 'income',
    category: '红包收入',
    page: req.query.page,
    limit: req.query.limit
  });
  res.json(result);
});

// 奶茶收入列表
router.get('/milk-tea', (req, res) => {
  const result = queryPagedRecords(req.user.id, req.query.year, req.query.month, {
    type: 'income',
    category: '奶茶',
    page: req.query.page,
    limit: req.query.limit
  });
  res.json(result);
});

// 派单列表
router.get('/dispatches', (req, res) => {
  const result = queryPagedRecords(req.user.id, req.query.year, req.query.month, {
    category: '派单',
    page: req.query.page,
    limit: req.query.limit
  });
  res.json(result);
});

// 获取记录列表
router.get('/', (req, res) => {
  const { type, page = 1, limit = 20 } = req.query;
  const validatedPage = validatePage(page, 1);
  const validatedLimit = validateLimit(limit, config.pagination.defaultLimit, config.pagination.maxLimit);
  const offset = (validatedPage - 1) * validatedLimit;
  let sql = 'SELECT * FROM records WHERE user_id = ?';
  const params = [req.user.id];
  if (type) {
    sql += ' AND type = ?';
    params.push(type);
  }
  sql += ' ORDER BY created_at DESC LIMIT ? OFFSET ?';
  params.push(validatedLimit, offset);
  res.json(db.prepare(sql).all(...params));
});

// 更新记录
router.put('/:id', (req, res, next) => {
  try {
    const { quantity, unit_price, rebate, amount, boss, partner, source, destination, note, created_at } = req.body;
    const id = Number(req.params.id);

    if (!id || id <= 0) {
      throw new AppError('无效的记录ID', 400);
    }

    // 获取原有记录以判断类别（派单允许负数金额）
    const existing = db.prepare('SELECT category FROM records WHERE id = ? AND user_id = ?').get(id, req.user.id);
    if (!existing) {
      throw new AppError('记录不存在', 404);
    }

    const validatedAmount = existing.category === '派单'
      ? validateNumber(amount, '金额')
      : validateNumber(amount, '金额', 0);
    const validatedQuantity = quantity === undefined || quantity === null || quantity === '' ? null : validateNumber(quantity, '数量', 0);
    const validatedUnitPrice = unit_price === undefined || unit_price === null || unit_price === '' ? null : validateNumber(unit_price, '单价', 0);
    const validatedRebate = rebate === undefined || rebate === null || rebate === '' ? null : validateNumber(rebate, '返点');
    const validatedCreatedAt = validateIsoDate(created_at, '创建时间');

    db.prepare(`
      UPDATE records SET quantity = ?, unit_price = ?, rebate = ?, amount = ?, boss = ?, partner = ?, source = ?, destination = ?, note = ?, created_at = ?
      WHERE id = ? AND user_id = ?
    `).run(
      validatedQuantity,
      validatedUnitPrice,
      validatedRebate,
      validatedAmount,
      optionalString(boss, '老板', 100),
      optionalString(partner, '陪玩', 100),
      optionalString(source, '来源', 100),
      optionalString(destination, '去向', 100),
      optionalString(note, '备注', 500),
      validatedCreatedAt,
      id,
      req.user.id
    );

    logger.debug(`用户 ${req.user.username} 更新记录: ${id}`);
    res.json({ success: true });
  } catch (err) {
    next(err);
  }
});

// 删除记录
router.delete('/:id', (req, res, next) => {
  try {
    const id = Number(req.params.id);

    if (!id || id <= 0) {
      throw new AppError('无效的记录ID', 400);
    }

    db.prepare('DELETE FROM records WHERE id = ? AND user_id = ?').run(id, req.user.id);

    logger.info(`用户 ${req.user.username} 删除记录: ${id}`);
    res.json({ success: true });
  } catch (err) {
    next(err);
  }
});

module.exports = router;