using Domain.AggregateModel.AppAggregate;
using Domain.AggregateModel.LinkAggregate;
using Domain.Exceptions;
using MediatR;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace QRCodeService.Application.Commands
{
    public class CreateLinkCommandHandler : IRequestHandler<CreateLinkCommand, Link>
    {
        readonly IAppRepository appRepository;
        readonly ILinkRepository linkRepository;

        public CreateLinkCommandHandler(ILinkRepository linkRepository, IAppRepository appRepository)
        {
            this.linkRepository = linkRepository;
            this.appRepository = appRepository;
        }

         async Task<Link> IRequestHandler<CreateLinkCommand, Link>.Handle(CreateLinkCommand request, CancellationToken cancellationToken)
        {
            var app =  await appRepository.GetAsync(request.AppId);
            if (app == null)
            {
                throw new DomainException("app not found");
            }
            var link = new Link(app.BaseUrl, request.SuffixUrl, request.AppId);
            var dbLink = await linkRepository.GetAsync(link.ShortCode);
            if (dbLink != null)
            {
                throw new DomainException("url has been registed");
            }
            link = linkRepository.Add(link);
            await linkRepository.UnitOfWork.SaveEntitiesAsync();
            return link;
        }
    }
}