app.py

import gradio as gr
import requests
import base64
from pathlib import Path
import jwt
import time
import logging
import os

# Set up logging for debugging
logging.basicConfig(level=logging.DEBUG)
logger = logging.getLogger(__name__)

# Kling AI API configuration (keys hardcoded as requested)
ACCESS_KEY_ID = "AGBGmadNd9hakFYfahytyQQJtN8CJmDJ"
ACCESS_KEY_SECRET = "dp3pAe4PpdmnAHCAPgEd3PyLmBQrkMde"
API_URL = "https://api.klingai.com/v1/predictions"  # Updated endpoint

def generate_jwt_token():
    """Generate JWT token for Kling AI API authentication."""
    headers = {
        "alg": "HS256",
        "typ": "JWT"
    }
    payload = {
        "iss": ACCESS_KEY_ID,
        "exp": int(time.time()) + 1800,  # Token expires in 30 minutes
        "nbf": int(time.time()) - 5  # Effective 5 seconds before current time
    }
    token = jwt.encode(payload, ACCESS_KEY_SECRET, headers=headers)
    logger.debug(f"Generated JWT token: {token}")
    return token

def generate_image(image, prompt=""):
    """
    Call Kling AI API for single-reference face generation.
    
    Args:
        image: Uploaded image file (from Gradio, face image)
        prompt (str): Optional text prompt to guide transformation
    
    Returns:
        tuple: (Path to generated image or None, error message or None)
    """
    if not image:
        logger.error("No image uploaded")
        return None, "Error: Please upload a valid face image (PNG/JPEG, <10 MB, ≥512x512 pixels)."
    
    # Convert image to base64
    try:
        with open(image, "rb") as img_file:
            image_base64 = base64.b64encode(img_file.read()).decode("utf-8")
        logger.debug("Image converted to base64 successfully")
    except Exception as e:
        logger.error(f"Failed to process image: {str(e)}")
        return None, f"Error: Failed to process image. Ensure it’s a valid PNG/JPEG. Details: {str(e)}"
    
    headers = {
        "Authorization": f"Bearer {generate_jwt_token()}",
        "Content-Type": "application/json"
    }
    
    payload = {
        "image": image_base64,
        "prompt": prompt or "Transform the face into a cartoon style while preserving identity",
        "strength": 0.97,  # High reference strength for face preservation
        "output_format": "png"
    }
    
    try:
        logger.debug(f"Sending POST request to {API_URL} with payload: {payload}")
        response = requests.post(API_URL, json=payload, headers=headers, timeout=30)
        response.raise_for_status()
        data = response.json()
        logger.debug(f"API response: {data}")
        
        task_id = data.get("task_id") or data.get("taskId") or data.get("id")
        if not task_id:
            logger.error("No task ID returned in API response")
            return None, "Error: No task ID returned. Check API endpoint or keys at https://klingai.com/global/dev."
        
        # Poll for task completion
        status_url = f"{API_URL}/{task_id}"
        for _ in range(60):  # Poll for up to 5 minutes
            logger.debug(f"Polling status at {status_url}")
            status_response = requests.get(status_url, headers=headers, timeout=30)
            status_response.raise_for_status()
            status_data = status_response.json()
            logger.debug(f"Status response: {status_data}")
            status = status_data.get("status")
            if status == "succeeded":
                image_url = status_data.get("image_url") or status_data.get("result", {}).get("image_url") or status_data.get("output") or status_data.get("data", {}).get("image")
                if not image_url:
                    logger.error("No image URL in API response")
                    return None, "Error: No image URL in API response. Check API documentation at https://klingai.com/global/dev."
                # Download the image
                logger.debug(f"Downloading image from {image_url}")
                image_response = requests.get(image_url, timeout=30)
                image_response.raise_for_status()
                output_path = Path("/tmp/output_image.png")  # Use /tmp for Spaces compatibility
                with open(output_path, "wb") as f:
                    f.write(image_response.content)
                if not output_path.exists():
                    logger.error("Output image file not created")
                    return None, "Error: Failed to save output image."
                logger.debug(f"Image saved to {output_path}")
                return str(output_path), None
            elif status == "failed":
                logger.error("Image generation failed")
                return None, "Error: Image generation failed. Ensure the image contains a clear face and avoid NSFW or sensitive content."
            elif status == "processing" and status_data.get("progress", 0) >= 0.99:
                logger.error("Generation stuck at 99%")
                return None, "Error: Generation stuck at 99%. Check account credits or upgrade to a paid plan at https://klingai.com."
            time.sleep(5)
        
        logger.error("Image generation timed out")
        return None, "Error: Image generation timed out. Try during off-peak hours or check account status."
    
    except requests.exceptions.HTTPError as e:
        status_code = e.response.status_code if e.response else None
        error_data = e.response.json() if e.response and e.response.text else {}
        service_code = error_data.get("code", 0)
        logger.error(f"HTTP error: {status_code}, Service Code: {service_code}, Details: {str(e)}")
        
        if status_code == 404:
            if service_code == 1202:
                return None, "Error: Invalid request method (1202). Check https://klingai.com/global/dev for correct endpoint."
            elif service_code == 1203:
                return None, "Error: Resource does not exist (1203). Verify model or endpoint."
            return None, f"Error: Endpoint not found (404). Try https://api.klingai.com/v1/predictions or check https://klingai.com/global/dev."
        elif status_code == 401:
            if service_code == 1000:
                return None, "Error: Authentication failed (1000). Verify API keys are correct."
            elif service_code == 1001:
                return None, "Error: Authorization empty (1001). Ensure JWT token is included."
            elif service_code == 1002:
                return None, "Error: Authorization invalid (1002). Check key format."
            elif service_code == 1003:
                return None, "Error: Authorization not yet valid (1003). Adjust token start time (nbf)."
            elif service_code == 1004:
                return None, "Error: Authorization expired (1004). Generate a new token."
        elif status_code == 429:
            if service_code == 1100:
                return None, "Error: Account exception (1100). Verify account configuration at https://klingai.com."
            elif service_code == 1101:
                return None, "Error: Account in arrears (1101). Recharge your account."
            elif service_code == 1102:
                return None, "Error: Resource pack depleted or expired (1102). Purchase additional resources."
            elif service_code in (1302, 1303):
                return None, "Error: Rate limit exceeded (1302/1303). Reduce request frequency or contact support."
            elif service_code == 1304:
                return None, "Error: IP whitelisting issue (1304). Contact Kling AI support."
        elif status_code == 403 and service_code == 1103:
            return None, "Error: Unauthorized access (1103). Verify account permissions."
        elif status_code == 400:
            if service_code == 1200:
                return None, "Error: Invalid request parameters (1200). Check payload format."
            elif service_code == 1201:
                return None, "Error: Invalid parameters (1201). Use PNG/JPEG (<10 MB, ≥512x512) with a clear face."
            elif service_code == 1300:
                return None, "Error: Platform policy triggered (1300). Check input content."
            elif service_code == 1301:
                return None, "Error: Content security policy triggered (1301). Ensure the image contains a clear face and avoid NSFW content."
        elif status_code in (500, 503, 504):
            if service_code == 5000:
                return None, "Error: Server internal error (5000). Try again later."
            elif service_code == 5001:
                return None, "Error: Server unavailable due to maintenance (5001). Try again later."
            elif service_code == 5002:
                return None, "Error: Server timeout (5002). Try during off-peak hours."
        return None, f"Error: API request failed. HTTP {status_code}, Service Code {service_code}. Details: {str(e)}"
    except requests.exceptions.RequestException as e:
        logger.error(f"Network error: {str(e)}")
        return None, f"Error: Network issue. Ensure stable internet, disable VPN, and try again. Details: {str(e)}"

def chatbot_interface(image, prompt):
    """
    Gradio interface for single-reference face generation.
    
    Args:
        image: Uploaded image file (containing a face)
        prompt (str): Optional text prompt
    
    Returns:
        tuple: (Output image path for display, output image path for download, error message)
    """
    output_path, error = generate_image(image, prompt)
    if error:
        logger.debug(f"Error returned: {error}")
        return None, None, error
    logger.debug(f"Returning image path for display and download: {output_path}")
    return output_path, output_path, None

# Define Gradio interface
with gr.Blocks() as iface:
    gr.Markdown(
        """
        # Kling AI Single-Reference Face Generator
        Upload a PNG/JPEG image (<10 MB, ≥512x512 pixels) with a clear face to generate a transformed image using Kling AI API (reference strength 0.97). Avoid NSFW or sensitive content.
        """
    )
    with gr.Row():
        with gr.Column():
            image_input = gr.Image(type="filepath", label="Upload Face Image (PNG/JPEG, <10 MB, ≥512x512)")
            prompt_input = gr.Textbox(lines=2, placeholder="Enter an optional prompt (e.g., 'Turn this face into a cartoon')", label="Prompt")
            generate_button = gr.Button("Generate")
        with gr.Column():
            output_image = gr.Image(label="Generated Face Image")
            output_file = gr.File(label="Download Generated Image")
            error_message = gr.Textbox(label="Status/Error Message", interactive=False)
    
    generate_button.click(
        fn=chatbot_interface,
        inputs=[image_input, prompt_input],
        outputs=[output_image, output_file, error_message]
    )

# Launch the interface
if __name__ == "__main__":
    logger.debug("Launching Gradio interface")
    iface.launch(server_name="0.0.0.0", server_port=7860)