FrontOffice/src/FrontOffice.Main/Pages/Checkout.razor.cs

using CMSMicroservice.Protobuf.Protos.Package;
using CMSMicroservice.Protobuf.Protos.Transactions;
using CMSMicroservice.Protobuf.Protos.UserAddress;
using CMSMicroservice.Protobuf.Protos.UserOrder;
using FrontOffice.Main.Utilities;
using Google.Protobuf.WellKnownTypes;
using Microsoft.AspNetCore.Components;
using MudBlazor;
using Severity = MudBlazor.Severity;

namespace FrontOffice.Main.Pages;

public partial class Checkout
{
    [Inject] private PackageContract.PackageContractClient PackageClient { get; set; } = default!;
    [Inject] private UserAddressContract.UserAddressContractClient UserAddressContract { get; set; } = default!;
    [Inject] private UserOrderContract.UserOrderContractClient UserOrderContract { get; set; } = default!;
    [Inject] private TransactionsContract.TransactionsContractClient TransactionContract { get; set; } = default!;

    [Parameter] public long? PackageId { get; set; }

    private Pack? _selectedPackage;
    private List<CustomerAddressModel> _addresses = new();
    private CustomerAddressModel? _selectedAddress;
    private bool _isLoadingAddresses;
    private bool _isProcessingPayment;

    // Discount code
    private string _discountCode = string.Empty;
    private bool _isApplyingDiscount;
    private string _discountMessage = string.Empty;
    private bool _discountApplied;
    private long _discountAmount;
    private long _finalPrice;

    // Address management
    private bool _isSettingDefaultAddress;
    private long? _settingDefaultAddressId;

    private bool CanProceedToPayment => _selectedPackage != null && _selectedAddress != null;

    protected override async Task OnInitializedAsync()
    {
        await LoadPackageDetails();
        await LoadAddresses();
    }

    private async Task LoadPackageDetails()
    {
        if (PackageId.HasValue)
        {
            try
            {
                var response = await PackageClient.GetPackageAsync(new() { Id = PackageId.Value });
                if (response != null)
                {
                    _selectedPackage = new Pack(
                        Id: response.Id,
                        Title: response.Title,
                        Body: response.Description,
                        Image: response.ImagePath ?? string.Empty,
                        Price: response.Price
                    );
                    _finalPrice = _selectedPackage.Price;
                }
            }
            catch (Exception ex)
            {
                Snackbar.Add($"خطا در بارگذاری پکیج: {ex.Message}", Severity.Error);
            }
        }
    }

    private async Task LoadAddresses()
    {
        _isLoadingAddresses = true;
        try
        {
            var response = await UserAddressContract.GetCustomerAddressesAsync(request: new());
            if (response?.Models?.Any() == true)
            {
                _addresses = response.Models.ToList();
                // Select default address if available
                _selectedAddress = _addresses.FirstOrDefault(a => a.IsDefault) ?? _addresses.First();
            }
            else
            {
                _addresses = new List<CustomerAddressModel>();
            }
        }
        catch (Exception ex)
        {
            Snackbar.Add($"خطا در بارگذاری آدرس‌ها: {ex.Message}", Severity.Error);
            _addresses = new List<CustomerAddressModel>();
        }
        finally
        {
            _isLoadingAddresses = false;
            await InvokeAsync(StateHasChanged);
        }
    }

    private async Task SetAddressAsDefault(long addressId)
    {
        if (_isSettingDefaultAddress) return;

        _isSettingDefaultAddress = true;
        _settingDefaultAddressId = addressId;

        try
        {
            await UserAddressContract.SetAddressAsDefaultAsync(new() { Id = addressId });
            await LoadAddresses(); // Reload addresses to reflect the change
            Snackbar.Add("آدرس پیش‌فرض با موفقیت تغییر یافت.", Severity.Success);
        }
        catch (Exception ex)
        {
            Snackbar.Add($"خطا در تغییر آدرس پیش‌فرض: {ex.Message}", Severity.Error);
        }
        finally
        {
            _isSettingDefaultAddress = false;
            _settingDefaultAddressId = null;
            await InvokeAsync(StateHasChanged);
        }
    }

    private async Task ApplyDiscountCode()
    {
        if (string.IsNullOrWhiteSpace(_discountCode))
        {
            _discountMessage = "لطفاً کد تخفیف را وارد کنید.";
            _discountApplied = false;
            return;
        }

        _isApplyingDiscount = true;
        _discountMessage = string.Empty;

        try
        {
            // TODO: Implement discount code validation with backend
            // For now, simulate a discount
            if (_discountCode.ToUpper() == "TEST10")
            {
                _discountAmount = (long)(_selectedPackage!.Price * 0.1); // 10% discount
                _finalPrice = _selectedPackage!.Price - _discountAmount;
                _discountMessage = "کد تخفیف با موفقیت اعمال شد.";
                _discountApplied = true;
            }
            else
            {
                _discountMessage = "کد تخفیف نامعتبر است.";
                _discountApplied = false;
                _discountAmount = 0;
                _finalPrice = _selectedPackage!.Price;
            }
        }
        catch (Exception ex)
        {
            _discountMessage = "خطا در اعمال کد تخفیف.";
            _discountApplied = false;
            _discountAmount = 0;
            _finalPrice = _selectedPackage!.Price;
        }
        finally
        {
            _isApplyingDiscount = false;
            await InvokeAsync(StateHasChanged);
        }
    }

    private async Task ProcessPayment()
    {
        Snackbar.Add("درگاه پرداخت متصل نیست! لطفا در زمان دیگری مجددا تلاش فرمایید!", Severity.Warning);
        return;

        if (!CanProceedToPayment || _selectedPackage == null || _selectedAddress == null)
        {
            Snackbar.Add("لطفاً پکیج و آدرس را انتخاب کنید.", Severity.Warning);
            return;
        }

        _isProcessingPayment = true;

        try
        {
            // Step 1: Create payment request
            var paymentRequest = new CustomerPaymentRequestRequest
            {
                Amount = _finalPrice,
                CallbackUrl = $"{Navigation.BaseUri}checkout/callback",
                Description = $"خرید پکیج {_selectedPackage.Title}",
                Currency = CurrencyEnum.Irt,
                Type = TransactionTypeEnum.Real
            };

            var paymentResponse = await TransactionContract.CustomerPaymentRequestAsync(paymentRequest);

            if (string.IsNullOrEmpty(paymentResponse.PaymentGWUrl))
                Snackbar.Add("آدرس درگاه پرداخت دریافت نشد.", Severity.Error);

            // Step 2: Create user order
            var orderRequest = new CreateNewUserOrderRequest
            {
                Amount = _finalPrice,
                PackageId = _selectedPackage.Id,
                PaymentStatus = CMSMicroservice.Protobuf.Protos.PaymentStatus.Pending
            };

            var orderResponse = await UserOrderContract.CreateNewUserOrderAsync(orderRequest);

            // Step 3: Redirect to payment gateway
            Navigation.NavigateTo(paymentResponse.PaymentGWUrl);
        }
        catch (Exception ex)
        {
            Snackbar.Add($"خطا در پردازش پرداخت: {ex.Message}", Severity.Error);
        }
        finally
        {
            _isProcessingPayment = false;
            await InvokeAsync(StateHasChanged);
        }
    }

    private record Pack(long Id, string Title, string Body, string Image, long Price);
}