FACULTATE-HEALTHCARE_MANAGER/backend/Application/Endpoints/Appointments/DeleteAppointment/DeleteAppointmentHandler.cs

using Application.Services.Database.MongoDB;
using Application.Services.Database.PostgreSQL;
using Domain.Entities;

namespace Application.Endpoints.Appointments.DeleteAppointment;

public class DeleteAppointmentHandler(
    IAppointmentsMongoDbService appointmentsMongoDbService,
    IPatientRepository patientRepository,
    IDoctorRepository doctorRepository)
{
    public async Task<BaseResponse> Handle(AppointmentInformation request, CancellationToken token)
    {
        var validation = new DeleteAppointmentValidator(appointmentsMongoDbService,
            doctorRepository, patientRepository);
        var validationResult = await validation.ValidateAsync(request, token);

        if (!validationResult.IsValid)
        {
            var firstError = validationResult.Errors.FirstOrDefault();
            var errorCode = int.TryParse(firstError.ErrorCode, out var code) ? code : -1;
            var errorMessage = firstError.ErrorMessage;

            return new BaseResponse
            {
                StatusCode = errorCode,
                Message = errorMessage,
                Data = null
            };
        }

        var appointmentId = IdentifierGenerator.GenerateId(request.DoctorId, request.PatientId);
        var criteria = new List<(string FieldName, string Value)>
        {
            ("_id", appointmentId)
        };
        var appointments = await appointmentsMongoDbService.FindAsync<Appointment>(criteria, token);

        if (!appointments.Any())
            return new BaseResponse
            {
                StatusCode = HttpStatusCodes.NotFound,
                Message = "Appointment not found in system.",
                Data = null
            };

        var appointment = appointments[0];
        appointment.RemoveAppointment(request.Appointment);
        await appointmentsMongoDbService.ModifyAsync("_id", appointmentId, appointment, token);

        return new BaseResponse
        {
            StatusCode = HttpStatusCodes.OK,
            Message = "Appointment successfully removed.",
            Data = null
        };
    }
}