using Indotalent.ConfigBackEnd.Exceptions;
using Indotalent.ConfigBackEnd.Extensions;
using Indotalent.Infrastructure.Database;
using MediatR;
using Microsoft.EntityFrameworkCore;

namespace Indotalent.Features.Leave.LeaveBalance.Cqrs;

public class CreateLeaveBalanceRequest
{
    public string EmployeeId { get; set; } = string.Empty;
    public string LeaveCategoryId { get; set; } = string.Empty;
    public int Entitlement { get; set; }
    public int Used { get; set; }
    public int Pending { get; set; }
    public int Remaining { get; set; }
    public int Year { get; set; }
    public DateTime ValidFrom { get; set; }
    public DateTime ValidTo { get; set; }
    public int CarryForward { get; set; }
}

public class CreateLeaveBalanceResponse
{
    public string? Id { get; set; }
    public string? AutoNumber { get; set; }
}

public record CreateLeaveBalanceCommand(CreateLeaveBalanceRequest Data) : IRequest<CreateLeaveBalanceResponse>;

public class CreateLeaveBalanceHandler : IRequestHandler<CreateLeaveBalanceCommand, CreateLeaveBalanceResponse>
{
    private readonly AppDbContext _context;

    public CreateLeaveBalanceHandler(AppDbContext context) => _context = context;

    public async Task<CreateLeaveBalanceResponse> Handle(CreateLeaveBalanceCommand request, CancellationToken cancellationToken)
    {
        var isExists = await _context.LeaveBalance
            .AnyAsync(x => x.EmployeeId == request.Data.EmployeeId &&
                           x.LeaveCategoryId == request.Data.LeaveCategoryId &&
                           x.Year == request.Data.Year, cancellationToken);

        if (isExists)
        {
            throw new AlreadyExistsException("Leave Balance", $"{request.Data.EmployeeId} for Year {request.Data.Year}");
        }

        var entityName = nameof(Data.Entities.LeaveBalance);

        var autoNo = await _context.GenerateAutoNumberAsync(
            entityName: entityName,
            prefixTemplate: $"{entityName.ToShortNameConsonant(3)}/{{Year}}/",
            ct: cancellationToken
        );

        var entity = new Data.Entities.LeaveBalance
        {
            AutoNumber = autoNo,
            EmployeeId = request.Data.EmployeeId,
            LeaveCategoryId = request.Data.LeaveCategoryId,
            Entitlement = request.Data.Entitlement,
            Used = request.Data.Used,
            Pending = request.Data.Pending,
            Remaining = request.Data.Remaining,
            Year = request.Data.Year,
            ValidFrom = request.Data.ValidFrom,
            ValidTo = request.Data.ValidTo,
            CarryForward = request.Data.CarryForward
        };

        _context.LeaveBalance.Add(entity);
        await _context.SaveChangesAsync(cancellationToken);

        return new CreateLeaveBalanceResponse
        {
            Id = entity.Id,
            AutoNumber = entity.AutoNumber
        };
    }
}