const User = require('../models/userModel');
const Order = require('../models/orderModel');

// Get all users with their order statistics
exports.getAllUsers = async (req, res) => {
  try {
    // Get all users sorted by registration date (newest first)
    const users = await User.find()
      .select('-password')
      .sort({ createdAt: -1 })
      .lean();

    // Get current month date range
    const now = new Date();
    const startOfMonth = new Date(now.getFullYear(), now.getMonth(), 1);
    const endOfMonth = new Date(
      now.getFullYear(),
      now.getMonth() + 1,
      0,
      23,
      59,
      59,
    );

    // Get order counts for each user
    const usersWithStats = await Promise.all(
      users.map(async (user) => {
        // Count total orders for this user
        const totalOrders = await Order.countDocuments({ user: user._id });

        // Count orders this month
        const ordersThisMonth = await Order.countDocuments({
          user: user._id,
          createdAt: { $gte: startOfMonth, $lte: endOfMonth },
        });

        // Calculate total spent
        const orders = await Order.find({ user: user._id });
        const totalSpent = orders.reduce(
          (sum, order) => sum + order.totalPrice,
          0,
        );

        // Calculate tier based on order count
        let tier = 'حديدي'; // Iron (default for 0 orders)
        if (totalOrders >= 35) {
          tier = 'بلاتيني'; // Platinum
        } else if (totalOrders >= 20) {
          tier = 'ذهبي'; // Gold
        } else if (totalOrders >= 10) {
          tier = 'فضي'; // Silver
        } else if (totalOrders >= 1) {
          tier = 'برونزي'; // Bronze
        }

        // isActive is true if user has orders this month
        const isActive = ordersThisMonth > 0;

        return {
          ...user,
          totalOrders,
          totalSpent,
          tier,
          isActive,
        };
      }),
    );

    res.status(200).json({
      status: 'success',
      results: usersWithStats.length,
      data: usersWithStats,
    });
  } catch (err) {
    console.error('Error fetching users:', err);
    res.status(500).json({
      status: 'fail',
      message: 'Failed to fetch users',
      error: err.message,
    });
  }
};

// Get user by ID with their orders
exports.getUserById = async (req, res) => {
  try {
    const { id } = req.params;

    // Find user by ID
    const user = await User.findById(id).select('-password').lean();

    if (!user) {
      return res.status(404).json({
        status: 'fail',
        message: 'User not found',
      });
    }

    // Get all orders for this user
    const orders = await Order.find({ user: id })
      .populate('items.product', 'nameAr nameEn price images')
      .populate('promo', 'code discountType discountValue')
      .sort({ createdAt: -1 })
      .lean();

    // Get current month date range
    const now = new Date();
    const startOfMonth = new Date(now.getFullYear(), now.getMonth(), 1);
    const endOfMonth = new Date(
      now.getFullYear(),
      now.getMonth() + 1,
      0,
      23,
      59,
      59,
    );

    // Count total orders
    const totalOrders = orders.length;

    // Count orders this month
    const ordersThisMonth = orders.filter(
      (order) =>
        order.createdAt >= startOfMonth && order.createdAt <= endOfMonth,
    ).length;

    // Calculate total spent
    const totalSpent = orders.reduce((sum, order) => sum + order.totalPrice, 0);

    // Calculate tier based on order count
    let tier = 'حديدي'; // Iron (default for 0 orders)
    if (totalOrders >= 35) {
      tier = 'بلاتيني'; // Platinum
    } else if (totalOrders >= 20) {
      tier = 'ذهبي'; // Gold
    } else if (totalOrders >= 10) {
      tier = 'فضي'; // Silver
    } else if (totalOrders >= 1) {
      tier = 'برونزي'; // Bronze
    }

    // isActive is true if user has orders this month
    const isActive = ordersThisMonth > 0;

    res.status(200).json({
      status: 'success',
      data: {
        user: {
          ...user,
          totalOrders,
          totalSpent,
          tier,
          isActive,
        },
        orders,
      },
    });
  } catch (err) {
    console.error('Error fetching user by ID:', err);
    res.status(500).json({
      status: 'fail',
      message: 'Failed to fetch user details',
      error: err.message,
    });
  }
};

// Delete a user
exports.deleteUser = async (req, res) => {
  try {
    const user = await User.findByIdAndDelete(req.params.id);

    if (!user) {
      return res.status(404).json({
        status: 'fail',
        message: 'User not found',
      });
    }

    res.status(204).json({
      status: 'success',
      data: null,
    });
  } catch (err) {
    res.status(500).json({
      status: 'fail',
      message: 'Failed to delete user',
      error: err.message,
    });
  }
};