handles errors in a more use friendly way

frontend/lib/utils/fetch_trip.dart

@@ -1,5 +1,7 @@
+import "dart:async";
 import "dart:convert";
 import "dart:developer";
+import "dart:io";
 import "package:anyway/main.dart";
 import 'package:dio/dio.dart';
 
@@ -18,11 +20,6 @@ Dio dio = Dio(
     // also accept 500 errors, since we cannot rule out that the server is at fault. We still want to gracefully handle these errors
     validateStatus: (status) => status! <= 500,
     receiveDataWhenStatusError: true,
-    // api is notoriously slow
-    // headers: {
-    //   HttpHeaders.userAgentHeader: 'dio',
-    //   'api': '1.0.0',
-    // },
     contentType: Headers.jsonContentType,
     responseType: ResponseType.json,    
   ),
@@ -48,25 +45,70 @@ fetchTrip(
     );
   } catch (e) {
     trip.updateUUID("error");
-    trip.updateError(e.toString());
+      
+    // Format the error message to be more user friendly
+    String errorDescription;
+    if (e is DioException) {
+        errorDescription = e.message ?? "Unknown error";
+    } else if (e is SocketException) {
+        errorDescription = "No internet connection";
+    } else if (e is TimeoutException) {
+        errorDescription = "Request timed out";
+    } else {
+        errorDescription = "Unknown error";
+    }
+
+    String errorMessage = """
+      We're sorry, the following error was generated:
+
+      ${errorDescription.trim()}
+    """.trim();
+
+    trip.updateError(errorMessage);
     log(e.toString());
+    log(errorMessage);
     return;
   }
 
-  // handle errors
+  // handle more specific errors
   if (response.statusCode != 200) {
     trip.updateUUID("error");
-    String errorDetail;
+    String errorDescription;
     if (response.data.runtimeType == String) {
-      errorDetail = response.data;
+      errorDescription = response.data;
+    } else if (response.data.runtimeType == Map<String, dynamic>) {
+      errorDescription = response.data["detail"] ?? "Unknown error";
     } else {
-      errorDetail = response.data["detail"] ?? "Unknown error";
+      errorDescription = "Unknown error";
     }
-    trip.updateError(errorDetail);
-    log(errorDetail);
+
+    String errorMessage = """
+      We're sorry, our servers generated the following error:
+
+      ${errorDescription.trim()}
+      Please try again.
+    """.trim();
+    trip.updateError(errorMessage);
+    log(errorMessage);
     // Actualy no need to throw an exception, we can just log the error and let the user retry
     // throw Exception(errorDetail);
   } else {
+    
+    // if the response data is not json, throw an error
+    if (response.data is! Map<String, dynamic>) {
+      log("${response.data.runtimeType}");
+      trip.updateUUID("error");
+      String errorMessage = """
+        We're sorry, our servers generated the following error:
+
+        ${response.data.trim()}
+        Please try again.
+      """.trim();
+      trip.updateError(errorMessage);
+      log(errorMessage);
+      return;
+    }
+
     Map<String, dynamic> json = response.data;
 
     // only fill in the trip "meta" data for now