Fix: Improve input parsing and error handling for complex input structures

handler.py

@@ -50,18 +50,34 @@ class EndpointHandler:
         try:
             # Parse inputs
             if isinstance(inputs, str):
-                # Simple prompt - treat as generation
-                prompts = [inputs]
-                edit_type = "generate"
-                parameters = {}
-            else:
+                # Check if it's a JSON string
+                try:
+                    import json
+                    parsed_inputs = json.loads(inputs)
+                    if isinstance(parsed_inputs, dict):
+                        inputs = parsed_inputs
+                    else:
+                        # Simple prompt - treat as generation
+                        prompts = [inputs]
+                        edit_type = "generate"
+                        parameters = {}
+                except:
+                    # Simple prompt - treat as generation
+                    prompts = [inputs]
+                    edit_type = "generate"
+                    parameters = {}
+            
+            if isinstance(inputs, dict):
                 input_data = inputs.get("inputs", inputs)
                 if isinstance(input_data, str):
                     prompts = [input_data]
                     edit_type = "generate"
-                else:
+                elif isinstance(input_data, dict):
                     prompts = input_data.get("prompts", [input_data.get("prompt", "a simple sketch")])
                     edit_type = input_data.get("edit_type", "generate")
+                else:
+                    prompts = ["a simple sketch"]
+                    edit_type = "generate"
                 
                 parameters = inputs.get("parameters", {})
             
@@ -724,8 +740,9 @@ class EndpointHandler:
         dwg.add(dwg.rect(insert=(0, 0), size=(width, height), fill='white'))
         
         # Simple centered text
+        prompt_str = str(prompt)[:30] if prompt else "error"
         dwg.add(dwg.text(
-            f"DiffSketchEdit\n{prompt[:30]}...",
+            f"DiffSketchEdit\n{prompt_str}...",
             insert=(width/2, height/2),
             text_anchor="middle",
             font_size="12px",