const bcrypt = require('bcryptjs');
const User = require('../models/User');
const Role = require('../models/Role');
const Menu = require('../models/Menu');
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'
      }]
    });

    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'
      });
    }

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

    // 获取用户菜单权限
    let menus = [];
    // 超级管理员（isSuperAdmin为1或角色code为admin）返回所有菜单
    if (user.isSuperAdmin === 1 || (user.role && user.role.code === 'admin')) {
      // 超级管理员返回所有菜单
      const allMenus = await Menu.findAll({
        where: { 
          isDeleted: false,
          status: 'active',
          visible: 'show'
        },
        order: [['sort', 'ASC']]
      });
      menus = buildMenuTree(allMenus);
    } else if (user.roleId) {
      // 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: false,
            status: 'active',
            visible: 'show'
          },
          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
        },
        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 => ({
      id: menu.id,
      name: menu.name,
      code: menu.code,
      type: menu.type,
      path: menu.path,
      component: menu.component,
      icon: menu.icon,
      sort: menu.sort,
      visible: menu.visible,
      children: buildMenuTree(menus, menu.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
    });
  }
};