using AutoMapper;
using DigitalData.Core.Abstraction.Application.Repository;
using DigitalData.Core.Exceptions;
using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver;
using EnvelopeGenerator.Application.Common.Extensions;
using EnvelopeGenerator.Application.DocReceiverElements.Commands;
using EnvelopeGenerator.Domain.Entities;
using MediatR;
using Microsoft.EntityFrameworkCore;

namespace EnvelopeGenerator.Application.DocReceiverElements.Behaviors;

/// <summary>
/// Pipeline behavior that resolves and validates EnvelopeReceiver.
/// Executes FIRST in the signing process - before all other behaviors.
/// If EnvelopeReceiver is not provided, it queries the database using EnvelopeReceiverQueryBase parameters.
/// </summary>
public class EnvelopeReceiverResolutionBehavior : IPipelineBehavior<SigningCommand, Unit>
{
    private readonly IRepository<EnvelopeReceiver> _erRepo;
    private readonly IMapper _mapper;

    /// <summary>
    /// 
    /// </summary>
    /// <param name="erRepo"></param>
    /// <param name="mapper"></param>
    public EnvelopeReceiverResolutionBehavior(IRepository<EnvelopeReceiver> erRepo, IMapper mapper)
    {
        _erRepo = erRepo;
        _mapper = mapper;
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="request"></param>
    /// <param name="next"></param>
    /// <param name="cancellationToken"></param>
    /// <returns></returns>
    public async Task<Unit> Handle(SigningCommand request, RequestHandlerDelegate<Unit> next, CancellationToken cancellationToken)
    {
        // If EnvelopeReceiver is not provided, query it from database
        if (request.EnvelopeReceiver is null)
        {
            var er = await _erRepo.Query.Where(request, notnull: true).SingleOrDefaultAsync(cancellationToken)
                ?? throw new NotFoundException("EnvelopeReceiver not found");

            request.SetEnvelopeReceiver(_mapper.Map<EnvelopeReceiverDto>(er));
        }

        return await next(cancellationToken);
    }
}