using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
using PnvPanel.Application.Auth;
using PnvPanel.Application.Billing;
using PnvPanel.Application.Common.Interfaces;
using PnvPanel.Application.Common.Messaging;
using PnvPanel.Application.Common.Models;
using PnvPanel.Domain.Audit;
using PnvPanel.Domain.Billing;

namespace PnvPanel.Application.Admin.Billing;

/// <summary>
/// Продлевает оплату (max(текущий PaidUntil, сейчас) + период), возвращает в Active конфиги,
/// приостановленные за неуплату (Expired), и синхронизирует ExpiresAt на все конфиги пользователя —
/// зеркало UnblockUserCommandHandler, но по статусу Expired (биллинг), а не Disabled (блокировка).
/// </summary>
public sealed class ConfirmPaymentRequestCommandHandler(
    IAppDbContext dbContext,
    IIdentityService identityService,
    IXuiPanelGateway gateway,
    IRealtimeNotifier notifier,
    ITelegramNotifier telegramNotifier,
    ICurrentUser currentUser,
    ILogger<ConfirmPaymentRequestCommandHandler> logger
) : ICommandHandler<ConfirmPaymentRequestCommand, Result>
{
    public async Task<Result> Handle(
        ConfirmPaymentRequestCommand command,
        CancellationToken cancellationToken
    )
    {
        if (currentUser.UserId is not { } adminId)
            return Result.Failure(AuthErrors.Unauthorized);

        var request = await dbContext.PaymentRequests.FirstOrDefaultAsync(
            r => r.Id == command.RequestId,
            cancellationToken
        );
        if (request is null)
            return Result.Failure(BillingErrors.RequestNotFound);

        if (
            request.Status
            is not (PaymentRequestStatus.AwaitingPayment or PaymentRequestStatus.AwaitingConfirmation)
        )
            return Result.Failure(BillingErrors.RequestNotDecidable);

        var profile = await identityService.GetProfileAsync(request.UserId, cancellationToken);
        if (profile is null)
            return Result.Failure(AuthErrors.Unauthorized);

        var now = DateTimeOffset.UtcNow;
        var baseline = profile.BillingPaidUntil is { } paidUntil && paidUntil > now ? paidUntil : now;
        var newPaidUntil = baseline.AddMonths(request.Period.ToMonths());

        var extendResult = await identityService.ExtendBillingPaidUntilAsync(
            request.UserId,
            newPaidUntil,
            cancellationToken
        );
        if (!extendResult.IsSuccess)
            return extendResult;

        request.Confirm(adminId);

        await BillingConfigResumer.ResumeConfigsAsync(
            dbContext,
            gateway,
            notifier,
            logger,
            request.UserId,
            newPaidUntil,
            cancellationToken
        );

        dbContext.AuditLogs.Add(
            AuditLog.Create(
                adminId,
                "PaymentConfirmed",
                "PaymentRequest",
                request.Id.ToString(),
                metadata: null,
                AuditSource.Web
            )
        );

        await telegramNotifier.NotifyUserAsync(
            request.UserId,
            $"✅ Оплата подтверждена. Доступ продлён до {newPaidUntil:dd.MM.yyyy}.",
            null,
            cancellationToken
        );

        return Result.Success();
    }
}