hrynco-notification-service/HrynCo.NotificationService.Services/EmailTemplates/Update/UpdateEmailTemplateHandler.cs

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

namespace HrynCo.NotificationService.Services.EmailTemplates.Update;

internal sealed class UpdateEmailTemplateHandler
    : RequestHandler<UpdateEmailTemplateCommand, ServiceResult<Unit>>
{
    private readonly IEmailTemplateRepository _templates;

    public UpdateEmailTemplateHandler(
        IContextualSerilogLogger<UpdateEmailTemplateCommand> logger,
        IEmailTemplateRepository templates)
        : base(logger)
    {
        _templates = templates;
    }

    protected override async Task<ServiceResult<Unit>> DoOnHandle(
        UpdateEmailTemplateCommand request, CancellationToken cancellationToken)
    {
        var template = await _templates.GetAsync(
            request.ServiceName, request.Key, request.LanguageCode, cancellationToken);

        if (template is null)
            return Failure<Unit>("Template not found.", ServiceErrorCode.NotFound);

        template.Subject = request.Subject;
        template.HtmlBody = request.HtmlBody;
        template.TextBody = request.TextBody;
        template.Variables = request.Variables;
        template.Updated = DateTimeOffset.UtcNow;

        try
        {
            await _templates.UpdateAsync(template, cancellationToken);
        }
        catch (EmailTemplateWriteException error)
        {
            return Failure<Unit>(error.Message, error.IsConflict ? ServiceErrorCode.Conflict : ServiceErrorCode.InvalidRequest);
        }

        return Success(Unit.Value);
    }
}