using CMSMicroservice.Application.Common.Exceptions;
using CMSMicroservice.Application.Common.Interfaces;
using CMSMicroservice.Application.Common.Models;
using CMSMicroservice.Domain.Common;
using CMSMicroservice.Domain.Entities;
using CMSMicroservice.Domain.Entities.Club;
using CMSMicroservice.Domain.Entities.Commission;
using CMSMicroservice.Domain.Entities.History;
using CMSMicroservice.Domain.Enums;
using MediatR;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
using System.Globalization;

namespace CMSMicroservice.Application.ClubMembershipCQ.Commands.ActivateClubMembership;

public class ActivateClubMembershipCommandHandler : IRequestHandler<ActivateClubMembershipCommand, bool>
{
    private readonly IApplicationDbContext _context;
    private readonly ICurrentUserService _currentUser;
    private readonly IWeekDefinitionRepository _weekRepository;
    private readonly ILogger<ActivateClubMembershipCommandHandler> _logger;

    public ActivateClubMembershipCommandHandler(
        IApplicationDbContext context,
        ICurrentUserService currentUser,
        IWeekDefinitionRepository weekRepository,
        ILogger<ActivateClubMembershipCommandHandler> logger)
    {
        _context = context;
        _currentUser = currentUser;
        _weekRepository = weekRepository;
        _logger = logger;
    }

    public async Task<bool> Handle(
        ActivateClubMembershipCommand request, 
        CancellationToken cancellationToken)
    {
        try
        {
            _logger.LogInformation(
                "Activating club membership for UserId: {UserId}",
                request.UserId
            );

            // 1. بررسی کاربر
            var user = await _context.Users
                .FirstOrDefaultAsync(u => u.Id == request.UserId, cancellationToken);

            if (user == null)
            {
                _logger.LogWarning("User not found: {UserId}", request.UserId);
                throw new NotFoundException(nameof(User), request.UserId);
            }

            // 2. بررسی اینکه پکیج خریده باشد
            if (user.PackagePurchaseMethod == PackagePurchaseMethod.None)
            {
                _logger.LogWarning(
                    "User {UserId} has not purchased golden package yet",
                    request.UserId
                );
                throw new BadRequestException(
                    "برای فعالسازی باشگاه مشتریان ابتدا باید پکیج طلایی خریداری کنید"
                );
            }

            // 3. بررسی موجودی کیف پول
            var wallet = await _context.UserWallets
                .FirstOrDefaultAsync(w => w.UserId == user.Id, cancellationToken);

            if (wallet == null)
            {
                _logger.LogError("Wallet not found for UserId: {UserId}", request.UserId);
                throw new NotFoundException("کیف پول کاربر یافت نشد");
            }

            if (wallet.Balance < SystemConstants.BasePackageAmount)
            {
                _logger.LogWarning(
                    "User {UserId} has insufficient balance: {Balance}",
                    request.UserId,
                    wallet.Balance
                );
                throw new BadRequestException(
                    $"برای فعالسازی باشگاه مشتریان باید حداقل {SystemConstants.BasePackageAmount:N0} ریال موجودی اصلی داشته باشید"
                );
            }

            // 4. پیدا کردن UserOrder با PackageId
            var packageOrder = await _context.UserOrders
                .Include(o => o.Transaction)
                .Where(o =>
                    o.UserId == user.Id &&
                    o.PackageId != null &&
                    o.PaymentStatus == PaymentStatus.Success)
                .OrderByDescending(o => o.Created)
                .FirstOrDefaultAsync(cancellationToken);

            if (packageOrder == null)
            {
                _logger.LogWarning(
                    "No successful package order found for UserId: {UserId}",
                    request.UserId
                );
                throw new NotFoundException("سفارش پکیج طلایی یافت نشد");
            }

            // 5. بررسی Transaction
            if (packageOrder.Transaction == null)
            {
                _logger.LogError(
                    "Transaction not found for OrderId: {OrderId}",
                    packageOrder.Id
                );
                throw new NotFoundException("تراکنش مربوط به سفارش یافت نشد");
            }

            var transaction = packageOrder.Transaction;

            if (transaction.Type != TransactionType.DepositIpg &&
                transaction.Type != TransactionType.DepositExternal1)
            {
                _logger.LogWarning(
                    "Invalid transaction type for OrderId {OrderId}: {Type}",
                    packageOrder.Id,
                    transaction.Type
                );
                throw new BadRequestException(
                    "تراکنش معتبر برای فعالسازی باشگاه یافت نشد"
                );
            }

            // 6. بررسی عضویت فعلی
            var existingMembership = await _context.ClubMemberships
                .FirstOrDefaultAsync(c => c.UserId == user.Id, cancellationToken);

            // 6.1. دریافت مبلغ هدیه و هزینه فعالسازی از SystemConstants
            long giftValue = SystemConstants.ClubMembershipGiftValue;
            long activationFeeValue = SystemConstants.ClubActivationFee;
            
            _logger.LogInformation(
                "Using Club.MembershipGiftValue: {GiftValue}, Club.ActivationFee: {ActivationFee}",
                giftValue, activationFeeValue
            );

            ClubMembership entity;
            bool isNewMembership = existingMembership == null;
            var activationDate = DateTime.Now;

            if (isNewMembership)
            {
                // ایجاد عضویت جدید
                entity = new ClubMembership
                {
                    UserId = user.Id,
                    IsActive = true,
                    ActivatedAt = activationDate,
                    InitialContribution =activationFeeValue,
                    GiftValue = giftValue, // مقدار از تنظیمات
                    TotalEarned = 0,
                    PurchaseMethod = user.PackagePurchaseMethod
                };

                _context.ClubMemberships.Add(entity);
                
                _logger.LogInformation(
                    "Created new club membership for UserId {UserId} via {Method}, GiftValue: {GiftValue}",
                    user.Id,
                    user.PackagePurchaseMethod,
                    giftValue
                );
            }
            else
            {
                if (existingMembership.IsActive)
                {
                    _logger.LogInformation(
                        "User {UserId} is already an active club member",
                        user.Id
                    );
                    return true;
                }

                // فعال‌سازی مجدد — ActivatedAt حفظ میشه (overwrite نمیشه)
                entity = existingMembership;
                entity.IsActive = true;
                entity.PurchaseMethod = user.PackagePurchaseMethod;

                _context.ClubMemberships.Update(entity);
                
                _logger.LogInformation(
                    "Reactivated club membership for UserId {UserId}",
                    user.Id
                );
            }

            await _context.SaveChangesAsync(cancellationToken);

            // 6.5. ایجاد ClubMembershipCycle — هر خرید پکیج یک دور جدید
            var previousCycles = await _context.ClubMembershipCycles
                .Where(c => c.UserId == user.Id && c.IsCurrentCycle)
                .ToListAsync(cancellationToken);

            foreach (var prevCycle in previousCycles)
            {
                prevCycle.IsCurrentCycle = false;
            }

            var maxCycleNumber = await _context.ClubMembershipCycles
                .Where(c => c.ClubMembershipId == entity.Id)
                .MaxAsync(c => (int?)c.CycleNumber, cancellationToken) ?? 0;

            var newCycle = new ClubMembershipCycle
            {
                UserId = user.Id,
                ClubMembershipId = entity.Id,
                CycleNumber = maxCycleNumber + 1,
                PackagePurchasedAt = activationDate,
                PurchaseMethod = user.PackagePurchaseMethod,
                PackageAmount = SystemConstants.BasePackageAmount,
                IsCurrentCycle = true
            };

            _context.ClubMembershipCycles.Add(newCycle);
            await _context.SaveChangesAsync(cancellationToken);

            _logger.LogInformation(
                "Created ClubMembershipCycle #{CycleNumber} for UserId {UserId}, MembershipId {MembershipId}",
                newCycle.CycleNumber,
                user.Id,
                entity.Id
            );

            // 7. ثبت تاریخچه
            var history = new ClubMembershipHistory
            {
                ClubMembershipId = entity.Id,
                UserId = entity.UserId,
                OldIsActive = !isNewMembership && !existingMembership!.IsActive,
                NewIsActive = true,
                Action = ClubMembershipAction.Activated,
                Reason = isNewMembership
                    ? $"Initial activation via {user.PackagePurchaseMethod}"
                    : $"Reactivated via {user.PackagePurchaseMethod}",
                PerformedBy = _currentUser.GetPerformedBy()
            };

            _context.ClubMembershipHistories.Add(history);
            await _context.SaveChangesAsync(cancellationToken);

            // ⭐ 8. اضافه کردن مبلغ به Pool هفته جاری
            var currentWeekDefinitionId = GetCurrentWeekDefinitionId();
            var weeklyPool = await _context.WeeklyCommissionPools
                .FirstOrDefaultAsync(p => p.WeekDefinitionId == currentWeekDefinitionId, cancellationToken);

            if (weeklyPool == null)
            {
                // ایجاد Pool جدید برای این هفته
                weeklyPool = new WeeklyCommissionPool
                {
                    WeekDefinitionId = currentWeekDefinitionId,
                    TotalPoolAmount = activationFeeValue, // مبلغ هدیه به Pool اضافه میشه
                    TotalBalances = 0, // در CalculateWeeklyBalances محاسبه میشه
                    ValuePerBalance = 0, // در CalculateWeeklyCommissionPool محاسبه میشه
                    IsCalculated = false,
                    CalculatedAt = null
                };

                await _context.WeeklyCommissionPools.AddAsync(weeklyPool, cancellationToken);
                
                _logger.LogInformation(
                    "Created new WeeklyCommissionPool for WeekDefinitionId={WeekDefinitionId} with initial amount: {Amount}",
                    currentWeekDefinitionId,
                    giftValue
                );
            }
            else
            {
                // اضافه کردن به Pool موجود
                weeklyPool.TotalPoolAmount += activationFeeValue;
                _context.WeeklyCommissionPools.Update(weeklyPool);
                
                _logger.LogInformation(
                    "Added {Amount} to existing WeeklyCommissionPool for WeekDefinitionId={WeekDefinitionId}. New total: {NewTotal}",
                    activationFeeValue,
                    currentWeekDefinitionId,
                    weeklyPool.TotalPoolAmount
                );
            }

            await _context.SaveChangesAsync(cancellationToken);

            // 9. اضافه کردن ویژگی‌های باشگاه برای کاربر (فقط برای عضویت جدید)
            if (isNewMembership)
            {
                var featureIds = ClubFeatureTypeExtensions.GetAllFeatureIds();
                var clubFeatures = await _context.ClubFeatures
                    .Where(f => !f.IsDeleted && featureIds.Contains(f.Id))
                    .ToListAsync(cancellationToken);

                if (clubFeatures.Any())
                {
                var userClubFeatures = clubFeatures.Select(feature => new UserClubFeature
                {
                    UserId = user.Id,
                    ClubMembershipId = entity.Id,
                    ClubFeatureId = feature.Id,
                    GrantedAt = activationDate,
                    IsActive = true,
                    Notes = "اعطا شده به‌طور خودکار هنگام فعالسازی"
                }).ToList();                    _context.UserClubFeatures.AddRange(userClubFeatures);
                    await _context.SaveChangesAsync(cancellationToken);

                    _logger.LogInformation(
                        "Granted {Count} club features to UserId {UserId}",
                        clubFeatures.Count,
                        user.Id
                    );
                }
                else
                {
                    _logger.LogWarning(
                        "No club features found to grant to UserId {UserId}",
                        user.Id
                    );
                }
            }

            _logger.LogInformation(
                "Club membership activated successfully. UserId: {UserId}, MembershipId: {MembershipId}",
                user.Id,
                entity.Id
            );

            return true;
        }
        catch (Exception ex)
        {
            _logger.LogError(
                ex,
                "Error in ActivateClubMembershipCommand for UserId: {UserId}",
                request.UserId
            );
            throw;
        }
    }

    /// <summary>
    /// دریافت شناسه تعریف هفته جاری
    /// </summary>
    private long GetCurrentWeekDefinitionId()
    {
        var week = _weekRepository.GetCurrentWeek();
        if (week == null)
        {
            throw new InvalidOperationException("هفته جاری در سیستم تعریف نشده است");
        }
        return week.Id;
    }
}