import { HttpInterceptorFn, HttpErrorResponse } from '@angular/common/http';
import { inject } from '@angular/core';
import { Router } from '@angular/router';
import { catchError, throwError } from 'rxjs';
import { AuthService } from '../services/auth.service';

export const authInterceptor: HttpInterceptorFn = (req, next) => {
  const authService = inject(AuthService);
  const router = inject(Router);

  // Skip auth for login endpoint
  if (req.url.includes('/api/login')) {
    return next(req);
  }

  // Add auth token to requests
  const token = authService.getToken();
  if (token) {
    req = req.clone({
      setHeaders: {
        Authorization: `Bearer ${token}`
      }
    });
  }

  return next(req).pipe(
    catchError((error: HttpErrorResponse) => {
      if (error.status === 401) {
        authService.logout();
        router.navigate(['/login']);
      } else if (error.status === 409) {
        // Race condition - let components handle this
        console.warn('Race condition detected:', error.error?.detail);
      }
      return throwError(() => error);
    })
  );
};