admin/Azaion.AdminApi/BusinessExceptionHandler.cs

using System.Globalization;
using Microsoft.AspNetCore.Diagnostics;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json;

namespace Azaion.Common;

public class BusinessExceptionHandler(ILogger<BusinessExceptionHandler> logger) : IExceptionHandler
{
    public async ValueTask<bool> TryHandleAsync(HttpContext httpContext, Exception exception, CancellationToken cancellationToken)
    {
        if (exception is BusinessException ex)
        {
            logger.LogWarning(exception, ex.Message);
            httpContext.Response.StatusCode = MapStatusCode(ex.ExceptionEnum);
            httpContext.Response.ContentType = "application/json";

            if (ex.RetryAfterSeconds is { } retry && retry > 0)
                httpContext.Response.Headers.RetryAfter = retry.ToString(CultureInfo.InvariantCulture);

            var err = JsonConvert.SerializeObject(new
            {
                ErrorCode = ex.ExceptionEnum,
                ex.Message
            });
            await httpContext.Response.WriteAsync(err, cancellationToken).ConfigureAwait(false);
            return true;
        }

        if (exception is BadHttpRequestException badReq)
        {
            logger.LogWarning(exception, badReq.Message);
            httpContext.Response.StatusCode = StatusCodes.Status400BadRequest;
            httpContext.Response.ContentType = "application/json";

            var err = JsonConvert.SerializeObject(new
            {
                ErrorCode = 0,
                badReq.Message
            });
            await httpContext.Response.WriteAsync(err, cancellationToken).ConfigureAwait(false);
            return true;
        }

        return false;
    }

    private static int MapStatusCode(ExceptionEnum kind) => kind switch
    {
        // AZ-556 — `InvalidCredentials` covers unknown email, wrong password, disabled
        // account, lockout, and per-account rate-limit. Same 401 for all five so the
        // wire response carries no signal beyond the optional Retry-After header.
        ExceptionEnum.InvalidCredentials     => StatusCodes.Status401Unauthorized,
        ExceptionEnum.AccountLocked          => StatusCodes.Status423Locked,
        ExceptionEnum.LoginRateLimited       => StatusCodes.Status429TooManyRequests,
        ExceptionEnum.InvalidRefreshToken    => StatusCodes.Status401Unauthorized,
        ExceptionEnum.SessionNotFound        => StatusCodes.Status404NotFound,
        ExceptionEnum.InvalidMissionRequest  => StatusCodes.Status400BadRequest,
        ExceptionEnum.AircraftNotFound       => StatusCodes.Status400BadRequest,
        ExceptionEnum.MfaAlreadyEnabled      => StatusCodes.Status409Conflict,
        ExceptionEnum.MfaNotEnrolling        => StatusCodes.Status409Conflict,
        ExceptionEnum.MfaNotEnabled          => StatusCodes.Status409Conflict,
        ExceptionEnum.InvalidMfaCode         => StatusCodes.Status401Unauthorized,
        ExceptionEnum.InvalidMfaToken        => StatusCodes.Status401Unauthorized,
        _                                    => StatusCodes.Status409Conflict
    };
}