Add SubmitPromptResponse model and update submitPrompt method to return structured response

lib/src/comfyui_api.dart

@@ -14,6 +14,7 @@ import 'models/checkpoint.dart';
 import 'models/vae.dart';
 import 'models/lora.dart';
 import 'websocket_manager.dart';
+import 'models/submit_prompt_response.dart';
 
 /// A Dart SDK for interacting with the ComfyUI API
 class ComfyUiApi {
@@ -186,7 +187,7 @@ class ComfyUiApi {
   }
 
   /// Submits a prompt (workflow) to generate an image
-  Future<Map<String, dynamic>> submitPrompt(Map<String, dynamic> prompt) async {
+  Future<SubmitPromptResponse> submitPrompt(Map<String, dynamic> prompt) async {
     final response = await _httpClient.post(
       Uri.parse('$host/api/prompt'),
       headers: {'Content-Type': 'application/json'},
@@ -201,7 +202,7 @@ class ComfyUiApi {
       _webSocketManager.triggerOnPromptStart(promptId);
     }
 
-    return responseData;
+    return SubmitPromptResponse.fromJson(responseData);
   }
 
   /// Validates HTTP response and throws an exception if needed

lib/src/models/history_response.dart

@@ -1,3 +1,5 @@
+import 'package:http/http.dart' as http;
+
 class HistoryResponse {
   final Map<String, HistoryItem> items;
 
@@ -40,13 +42,13 @@ class Prompt {
   final int id;
   final String promptId;
   final Map<String, Node> nodes;
-  final ExtraPngInfo extraPngInfo;
+  final ExtraPngInfo? extraPngInfo;
 
   Prompt({
     required this.id,
     required this.promptId,
     required this.nodes,
-    required this.extraPngInfo,
+    this.extraPngInfo,
   });
 
   factory Prompt.fromJson(List<dynamic> json) {
@@ -56,7 +58,9 @@ class Prompt {
       nodes: (json[2] as Map<String, dynamic>).map(
         (key, value) => MapEntry(key, Node.fromJson(value)),
       ),
-      extraPngInfo: ExtraPngInfo.fromJson(json[3]['extra_pnginfo']),
+      extraPngInfo: json[3]['extra_pnginfo'] != null
+          ? ExtraPngInfo.fromJson(json[3]['extra_pnginfo'])
+          : null,
     );
   }
 }
@@ -196,6 +200,15 @@ class Image {
       type: json['type'] as String,
     );
   }
+
+  Future<List<int>> fetchImageBytes(String host) async {
+    final response =
+        await http.get(Uri.parse('$host/api/view?filename=$filename'));
+    if (response.statusCode != 200) {
+      throw Exception('Failed to fetch image: ${response.statusCode}');
+    }
+    return response.bodyBytes;
+  }
 }
 
 class Status {

lib/src/models/submit_prompt_response.dart

@@ -0,0 +1,27 @@
+class SubmitPromptResponse {
+  final String promptId;
+  final int number;
+  final Map<String, dynamic> nodeErrors;
+
+  SubmitPromptResponse({
+    required this.promptId,
+    required this.number,
+    required this.nodeErrors,
+  });
+
+  factory SubmitPromptResponse.fromJson(Map<String, dynamic> json) {
+    return SubmitPromptResponse(
+      promptId: json['prompt_id'],
+      number: json['number'],
+      nodeErrors: json['node_errors'] ?? {},
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'prompt_id': promptId,
+      'number': number,
+      'node_errors': nodeErrors,
+    };
+  }
+}