using BMA.EHR.Domain.Common;
using BMA.EHR.Domain.Shared;
using Microsoft.AspNetCore.Http;
using System.Net;

namespace BMA.EHR.Domain.Middlewares
{
    public class ErrorHandlerMiddleware
    {
        private readonly RequestDelegate _next;

        public ErrorHandlerMiddleware(RequestDelegate next)
        {
            _next = next;
        }

        public async Task Invoke(HttpContext context)
        {
            try
            {
                await _next(context);

                var response = context.Response;
                var statusCode = response.StatusCode;

                if (!response.HasStarted &&
                    (statusCode == (int)HttpStatusCode.Unauthorized || statusCode == (int)HttpStatusCode.Forbidden))
                {
                    var responseModel = new ResponseObject
                    {
                        Status = statusCode,
                        Message = statusCode == (int)HttpStatusCode.Unauthorized
                            ? GlobalMessages.NotAuthorized
                            : GlobalMessages.ForbiddenAccess
                    };

                    response.ContentType = "application/json";
                    await response.WriteAsJsonAsync(responseModel);
                }
            }
            catch (Exception error)
            {
                var response = context.Response;

                if (!response.HasStarted)
                {
                    response.Clear();
                    response.ContentType = "application/json";
                    response.StatusCode = (int)HttpStatusCode.InternalServerError;

                    var msg = error.Message;
                    var inner = error.InnerException;
                    while (inner != null)
                    {
                        msg += $" {inner.Message}\r\n";
                        inner = inner.InnerException;
                    }

                    var responseModel = new ResponseObject
                    {
                        Status = response.StatusCode,
                        Message = GlobalMessages.ExceptionOccured,
                        Result = msg
                    };

                    await response.WriteAsJsonAsync(responseModel);
                }
                else
                {
                    // logging กรณีที่ response เริ่มถูกส่งแล้ว
                    Console.WriteLine("Cannot write error response, stream already started.");
                    Console.WriteLine(error);
                }
            }
        }
    }
}