const bcrypt = require('bcryptjs');
const User = require('../models/User');
const Role = require('../models/Role');
const Menu = require('../models/Menu');
const Tenant = require('../models/Tenant');
const Category = require('../models/Category');
const Setting = require('../models/Setting');
const { SubscriptionPlan } = require('../models');
const { generateToken } = require('../middleware/auth');
const { logLogin, getClientIp } = require('../utils/logger');

// 登录
exports.login = async (req, res) => {
  const clientIp = getClientIp(req);
  const userAgent = req.headers['user-agent'];
  let username = req.body.username;

  try {
    const { password } = req.body;

    // 参数验证
    if (!username || !password) {
      await logLogin({
        username,
        loginType: 'login',
        ip: clientIp,
        userAgent,
        status: 'fail',
        message: '用户名和密码不能为空'
      });
      return res.status(400).json({
        code: 400,
        message: '用户名和密码不能为空'
      });
    }

    // 查找用户
    const user = await User.findOne({
      where: { username },
      include: [
        {
          model: Role,
          as: 'role'
        },
        {
          model: Tenant,
          as: 'tenant'
        }
      ]
    });

    if (!user) {
      await logLogin({
        username,
        loginType: 'login',
        ip: clientIp,
        userAgent,
        status: 'fail',
        message: '用户名或密码错误'
      });
      return res.status(401).json({
        code: 401,
        message: '用户名或密码错误'
      });
    }

    // 检查用户状态
    if (user.status === 'disabled') {
      await logLogin({
        userId: user.id,
        username: user.username,
        loginType: 'login',
        ip: clientIp,
        userAgent,
        status: 'fail',
        message: '账号已被禁用'
      });
      return res.status(401).json({
        code: 401,
        message: '账号已被禁用'
      });
    }

    // 验证密码
    const isPasswordValid = await bcrypt.compare(password, user.password);
    if (!isPasswordValid) {
      await logLogin({
        userId: user.id,
        username: user.username,
        loginType: 'login',
        ip: clientIp,
        userAgent,
        status: 'fail',
        message: '用户名或密码错误'
      });
      return res.status(401).json({
        code: 401,
        message: '用户名或密码错误'
      });
    }

    // 检查租户计费状态（仅非系统管理员需要检查）
    if (user.tenant && user.userType !== 'super_admin') {
      const billingStatus = user.tenant.billingStatus;
      if (billingStatus === 'trial_expired' || billingStatus === 'paid_expired') {
        await logLogin({
          userId: user.id,
          username: user.username,
          loginType: 'login',
          ip: clientIp,
          userAgent,
          status: 'fail',
          message: '账户已过期，请续费'
        });
        return res.status(403).json({
          code: 403,
          message: '您的账户已过期，请前往续费',
          data: {
            expired: true,
            billingStatus: billingStatus,
            trialEndDate: user.tenant.trialEndDate,
            paidEndDate: user.tenant.paidEndDate
          }
        });
      }
    }

    // 生成 Token
    const token = generateToken(user);

    // 获取用户菜单权限
    let menus = [];
    // 系统管理员返回所有菜单
    if (user.userType === 'super_admin') {
      const allMenus = await Menu.findAll({
        where: { 
          isDeleted: 0,
          status: 'active'
        },
        order: [['sort', 'ASC']]
      });
      menus = buildMenuTree(allMenus);
    } else if (user.roleId) {
      // 租户管理员和普通用户返回角色分配的菜单
      const roleData = await Role.findByPk(user.roleId, {
        include: [{
          model: Menu,
          as: 'menus',
          where: { 
            isDeleted: 0,
            status: 'active'
          },
          through: { attributes: [] }
        }]
      });
      
      if (roleData && roleData.menus) {
        const sortedMenus = roleData.menus.sort((a, b) => a.sort - b.sort);
        menus = buildMenuTree(sortedMenus);
      }
    }

    // 记录登录成功日志
    await logLogin({
      userId: user.id,
      username: user.username,
      loginType: 'login',
      ip: clientIp,
      userAgent,
      status: 'success',
      message: '登录成功'
    });

    // 返回用户信息和 Token
    res.json({
      code: 200,
      message: '登录成功',
      data: {
        token,
        userInfo: {
          id: user.id,
          username: user.username,
          nickname: user.nickname,
          role: user.role,
          tenantId: user.tenantId,
          userType: user.userType
        },
        tenant: user.tenant,
        menus
      }
    });
  } catch (error) {
    console.error('登录错误:', error);
    await logLogin({
      username,
      loginType: 'login',
      ip: clientIp,
      userAgent,
      status: 'fail',
      message: error.message
    });
    res.status(500).json({
      code: 500,
      message: '登录失败',
      error: error.message
    });
  }
};

// 登出
exports.logout = async (req, res) => {
  try {
    // 记录登出日志
    const user = req.user || {};
    await logLogin({
      userId: user.id,
      username: user.username,
      loginType: 'logout',
      ip: getClientIp(req),
      userAgent: req.headers['user-agent'],
      status: 'success',
      message: '登出成功'
    });

    res.json({
      code: 200,
      message: '登出成功'
    });
  } catch (error) {
    console.error('登出错误:', error);
    res.json({
      code: 200,
      message: '登出成功'
    });
  }
};

// 构建菜单树
function buildMenuTree(menus, parentId = null) {
  return menus
    .filter(menu => menu.parentId === parentId)
    .map(menu => {
      // 获取菜单的原始数据（处理 Sequelize 模型对象）
      const menuData = menu.toJSON ? menu.toJSON() : menu;
      return {
        id: menuData.id,
        name: menuData.name,
        code: menuData.code,
        type: menuData.type,
        path: menuData.path,
        component: menuData.component,
        icon: menuData.icon,
        sort: menuData.sort,
        visible: menuData.visible,
        status: menuData.status,
        isDeleted: menuData.isDeleted,
        parentId: menuData.parentId,
        children: buildMenuTree(menus, menuData.id)
      };
    });
}

// 获取当前用户信息
exports.getCurrentUser = async (req, res) => {
  try {
    // req.user 由 authMiddleware 附加
    res.json({
      code: 200,
      message: '获取成功',
      data: req.user
    });
  } catch (error) {
    console.error('获取用户信息错误:', error);
    res.status(500).json({
      code: 500,
      message: '获取用户信息失败',
      error: error.message
    });
  }
};

// 修改密码
exports.changePassword = async (req, res) => {
  try {
    const { oldPassword, newPassword } = req.body;
    const userId = req.user.id;

    // 参数验证
    if (!oldPassword || !newPassword) {
      return res.status(400).json({
        code: 400,
        message: '原密码和新密码不能为空'
      });
    }

    if (newPassword.length < 6) {
      return res.status(400).json({
        code: 400,
        message: '新密码长度不能少于6位'
      });
    }

    // 查找用户
    const user = await User.findByPk(userId);
    if (!user) {
      return res.status(404).json({
        code: 404,
        message: '用户不存在'
      });
    }

    // 验证原密码
    const isPasswordValid = await bcrypt.compare(oldPassword, user.password);
    if (!isPasswordValid) {
      return res.status(400).json({
        code: 400,
        message: '原密码错误'
      });
    }

    // 加密新密码
    const hashedPassword = await bcrypt.hash(newPassword, 10);

    // 更新密码
    await user.update({ password: hashedPassword });

    res.json({
      code: 200,
      message: '密码修改成功'
    });
  } catch (error) {
    console.error('修改密码错误:', error);
    res.status(500).json({
      code: 500,
      message: '修改密码失败',
      error: error.message
    });
  }
};

// 租户自助注册
exports.registerTenant = async (req, res) => {
  const { 
    contactName, 
    contactPhone, 
    contactEmail,
    adminUsername,
    adminPassword
  } = req.body;

  try {
    // 参数验证
    if (!contactName || !contactPhone || !contactEmail || !adminUsername || !adminPassword) {
      return res.status(400).json({
        code: 400,
        message: '请填写所有必填项'
      });
    }

    // 检查管理员账号是否已存在
    const existingUser = await User.findOne({ where: { username: adminUsername } });
    if (existingUser) {
      return res.status(400).json({
        code: 400,
        message: '管理员账号已存在'
      });
    }

    // 查询默认套餐
    const defaultPlan = await SubscriptionPlan.findOne({
      where: { 
        isDefault: true, 
        isDeleted: 0 
      }
    });

    if (!defaultPlan) {
      return res.status(500).json({
        code: 500,
        message: '系统未配置默认套餐，请联系管理员'
      });
    }

    // 生成租户编码：时间戳 + 随机数
    const timestamp = Date.now().toString(36).toUpperCase();
    const random = Math.random().toString(36).substring(2, 6).toUpperCase();
    const code = `T${timestamp}${random}`;

    const now = new Date();
    const trialEndDate = new Date(Date.now() + 30 * 24 * 60 * 60 * 1000);

    // 创建租户（使用默认套餐配置）
    const tenant = await Tenant.create({
      code,
      contactName,
      contactPhone,
      contactEmail,
      maxUsers: defaultPlan.maxUsers,
      maxApartments: defaultPlan.maxApartments,
      maxRooms: defaultPlan.maxRooms,
      status: 'active',
      billingStatus: 'trial_active',
      planId: defaultPlan.id,
      trialStartDate: now,
      trialEndDate: trialEndDate,
      currentPeriodStart: now,
      currentPeriodEnd: trialEndDate
    });

    // 创建租户管理员账号
    const hashedPassword = await bcrypt.hash(adminPassword, 10);
    const user = await User.create({
      username: adminUsername,
      password: hashedPassword,
      nickname: adminUsername,
      tenantId: tenant.id,
      userType: 'tenant_admin',
      status: 'active'
    });

    // 创建默认管理员角色并分配所有菜单权限
    const adminRole = await Role.create({
      name: '管理员',
      code: 'admin',
      description: '租户默认管理员角色，拥有所有权限',
      tenantId: tenant.id,
      status: 'active'
    });

    // 获取基础菜单并分配给角色（新租户只分配基础功能菜单）
    const basicMenus = await Menu.findAll({
      where: {
        isDeleted: 0,
        status: 'active',
        isBasic: 1
      }
    });

    if (basicMenus.length > 0) {
      const menuIds = basicMenus.map(menu => menu.id);
      await adminRole.setMenus(menuIds);
    }

    // 将用户关联到管理员角色
    await user.update({ roleId: adminRole.id });

    // 初始化默认收支类目
    const defaultCategories = [
      // 收入类目
      { name: '租金', code: 'rent', type: 'income', sort: 1 },
      { name: '水费', code: 'water', type: 'income', sort: 2 },
      { name: '电费', code: 'electricity', type: 'income', sort: 3 },
      { name: '燃气费', code: 'gas', type: 'income', sort: 4 },
      { name: '押金', code: 'deposit', type: 'income', sort: 5 },
      { name: '物业费', code: 'property_fee', type: 'income', sort: 6 },
      { name: '违约金', code: 'penalty', type: 'income', sort: 7 },
      { name: '其他收入', code: 'other_income', type: 'income', sort: 8 },
      // 支出类目
      { name: '维修费', code: 'maintenance', type: 'expense', sort: 1 },
      { name: '中介费', code: 'agency_fee', type: 'expense', sort: 2 },
      { name: '物业费', code: 'property_fee_expense', type: 'expense', sort: 3 },
      { name: '水费', code: 'water_expense', type: 'expense', sort: 4 },
      { name: '电费', code: 'electricity_expense', type: 'expense', sort: 5 },
      { name: '燃气费', code: 'gas_expense', type: 'expense', sort: 6 },
      { name: '装修费', code: 'renovation', type: 'expense', sort: 7 },
      { name: '其他支出', code: 'other_expense', type: 'expense', sort: 8 }
    ];

    for (const category of defaultCategories) {
      await Category.create({
        ...category,
        tenantId: tenant.id,
        status: 'active',
        isDefault: 1,
        createBy: user.id
      });
    }

    // 初始化默认系统设置
    const defaultSettings = [
      { key: 'expireReminderDays', value: '30', description: '房间到期提前提醒天数' }
    ];

    for (const setting of defaultSettings) {
      await Setting.create({
        ...setting,
        tenantId: tenant.id,
        createBy: user.id
      });
    }

    res.json({
      code: 200,
      message: '注册成功，欢迎试用',
      data: {
        tenantId: tenant.id,
        code: tenant.code,
        status: tenant.status
      }
    });
  } catch (error) {
    console.error('租户注册失败:', error);
    res.status(500).json({
      code: 500,
      message: '注册失败',
      error: error.message
    });
  }
};