Lora preset handling.

app.py

@@ -13,6 +13,7 @@ from huggingface_hub import hf_hub_download
 import numpy as np
 from PIL import Image
 import gradio as gr
+import json
 import random
 
 # --- I2V (Image-to-Video) Configuration ---
@@ -107,6 +108,59 @@ MAX_FRAMES_MODEL = 81
 default_prompt_i2v = "Cinematic motion, smooth animation, detailed textures, dynamic lighting, professional cinematography"
 default_negative_prompt = "Static image, no motion, blurred details, overexposed, underexposed, low quality, worst quality, JPEG artifacts, ugly, incomplete, extra fingers, poorly drawn hands, poorly drawn faces, deformed, disfigured, misshapen limbs, fused fingers, still picture, messy background, watermark, text, signature, three legs, many people in the background, walking backwards"
 
+# --- LoRA Preset Helper Functions ---
+def parse_lset_prompt(lset_prompt):
+    """Parses a .lset prompt, resolving variables with their defaults."""
+    # Find all variable declarations like ! {Subject}="woman"
+    variables = dict(re.findall(r'! \{(\w+)\}="([^"]+)"', lset_prompt))
+    
+    # Remove the declaration lines to get the clean prompt template
+    prompt_template = re.sub(r'! \{\w+\}="[^"]+"\n?', '', lset_prompt).strip()
+    
+    # Replace placeholders with their default values
+    resolved_prompt = prompt_template
+    for key, value in variables.items():
+        resolved_prompt = resolved_prompt.replace(f"{{{key}}}", value)
+        
+    return resolved_prompt
+
+def handle_lora_selection_change(lora_name, current_prompt):
+    """
+    When a LoRA is selected, this function tries to find a corresponding .lset file,
+    parses it, and appends the generated prompt to the current prompt.
+    """
+    if not lora_name or lora_name == "None":
+        return gr.update() # No LoRA selected, do not change the prompt.
+
+    try:
+        # Construct the .lset filename from the .safetensors filename
+        lset_filename = os.path.splitext(lora_name)[0] + ".lset"
+        
+        # Download the .lset file from the same subfolder as the LoRA
+        lset_path = hf_hub_download(
+            repo_id=I2V_LORA_REPO_ID,
+            filename=lset_filename,
+            subfolder=I2V_LORA_SUBFOLDER,
+            repo_type='model'
+        )
+        
+        with open(lset_path, 'r', encoding='utf-8') as f:
+            lset_data = json.load(f)
+        
+        lset_prompt_raw = lset_data.get("prompt")
+        if not lset_prompt_raw:
+            return gr.update()
+
+        resolved_prompt = parse_lset_prompt(lset_prompt_raw)
+        new_prompt = f"{current_prompt} {resolved_prompt}".strip()
+        gr.Info(f"✅ Appended prompt from '{lset_filename}'")
+        return gr.update(value=new_prompt)
+    except Exception as e:
+        # This is expected if a .lset file doesn't exist for the selected LoRA.
+        print(f"Info: Could not process .lset for '{lora_name}'. Reason: {e}")
+        gr.Info(f"ℹ️ No prompt preset found for '{lora_name}'.")
+        return gr.update()
+
 # --- Helper Functions ---
 def sanitize_prompt_for_filename(prompt: str, max_len: int = 60) -> str:
     """Sanitizes a prompt string to be used as a valid filename."""
@@ -301,6 +355,11 @@ with gr.Blocks() as demo:
 
     # --- Event Handlers ---
     # I2V Handlers
+    i2v_lora_name.change(
+        fn=handle_lora_selection_change,
+        inputs=[i2v_lora_name, i2v_prompt],
+        outputs=[i2v_prompt]
+    )
     i2v_input_image.upload(
         fn=handle_image_upload_for_dims_wan,
         inputs=[i2v_input_image],