using HrynCo.NotificationService.DAL.Abstract.Repositories;
using HrynCo.NotificationService.DAL.Abstract.Templates;
using HrynCo.NotificationService.Services.Core;
using HrynCo.NotificationService.Services.Logging;
using static HrynCo.NotificationService.Services.Core.ServiceResultHelper;

namespace HrynCo.NotificationService.Services.TemplateDefinitions;

internal sealed class DeleteServiceLanguageVersionsHandler(
    IContextualSerilogLogger<DeleteServiceLanguageVersionsCommand> logger, INotificationServiceRepository services)
    : RequestHandler<DeleteServiceLanguageVersionsCommand, ServiceResult<Unit>>(logger)
{
    protected override async Task<ServiceResult<Unit>> DoOnHandle(DeleteServiceLanguageVersionsCommand request, CancellationToken cancellationToken)
    {
        if (!request.ConfirmDelete || request.ExpectedVersionCount < 0 || request.Revision == Guid.Empty)
            return Failure<Unit>("ConfirmDelete must be true; a nonnegative expectedVersionCount and nonempty service revision are required.", ServiceErrorCode.InvalidRequest);
        var service = await services.GetAsync(request.ServiceId, cancellationToken);
        if (service?.Languages.Any(l => l.Id == request.LanguageId) != true)
            return Failure<Unit>("Service language not found.", ServiceErrorCode.NotFound);
        try
        {
            await services.RemoveLanguageAsync(request.ServiceId, request.LanguageId, request.ExpectedVersionCount, request.Revision, cancellationToken);
            return Success(Unit.Value);
        }
        catch (EmailTemplateWriteException error)
        {
            return Failure<Unit>(error.Message, error.IsConflict ? ServiceErrorCode.Conflict : ServiceErrorCode.InvalidRequest);
        }
    }
}