using AutoMapper;
using EnvelopeGenerator.Application.Contracts.Repositories;
using EnvelopeGenerator.Application.DTOs;
using EnvelopeGenerator.Common;
using MediatR;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Logging;

namespace EnvelopeGenerator.Application.EmailTemplates.Queries.Read;

/// <summary>
/// 
/// </summary>
public class ReadEmailTemplateQueryHandler : IRequestHandler<ReadEmailTemplateQuery, ReadEmailTemplateResponse?>
{
    private readonly IMapper _mapper;

    private readonly IEmailTemplateRepository _repository;

    /// <summary>
    /// Initialisiert eine neue Instanz der <see cref="EmailTemplateController"/>-Klasse.
    /// </summary>
    /// <param name="mapper">
    /// <param name="repository">
    /// Die AutoMapper-Instanz, die zum Zuordnen von Objekten verwendet wird.
    /// </param>
    public ReadEmailTemplateQueryHandler(IMapper mapper, IEmailTemplateRepository repository)
    {
        _mapper = mapper;
        _repository = repository;
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="request"></param>
    /// <param name="cancellationToken"></param>
    /// <returns></returns>
    /// <exception cref="InvalidOperationException"></exception>
    public async Task<ReadEmailTemplateResponse?> Handle(ReadEmailTemplateQuery request, CancellationToken cancellationToken)
    {
        var temp = request.Id is int id
            ? await _repository.ReadByIdAsync(id)
            : request.Type is Constants.EmailTemplateType type
                ? await _repository.ReadByNameAsync(type)
                : throw new InvalidOperationException("Either a valid integer ID or a valid EmailTemplateType must be provided in the request.");

        var res = _mapper.Map<ReadEmailTemplateResponse>(temp);

        return res;
    }
}