services/vision_service.py

import logging
import base64
import io
from typing import Optional, Dict, Any
from llama_cpp import Llama
from llama_cpp.llama_chat_format import Llava15ChatHandler
from huggingface_hub import hf_hub_download
from PIL import Image

from config import config
# ADD THIS IMPORT
from utils.json_extractor import extract_json_from_content

logger = logging.getLogger("vision-service")

class VisionService:
    """Service for vision-language model interactions"""
    
    def __init__(self):
        self.model: Optional[Llama] = None
        self.chat_handler: Optional[Llava15ChatHandler] = None
        
    async def initialize(self) -> None:
        # ... (Same as your original code) ...
        try:
            logger.info(f"Downloading vision model: {config.VISION_MODEL_FILE}...")
            model_path = hf_hub_download(
                repo_id=config.VISION_MODEL_REPO,
                filename=config.VISION_MODEL_FILE,
                cache_dir=config.HF_HOME
            )
            
            logger.info(f"Downloading vision projector: {config.VISION_MMPROJ_FILE}...")
            mmproj_path = hf_hub_download(
                repo_id=config.VISION_MODEL_REPO,
                filename=config.VISION_MMPROJ_FILE,
                cache_dir=config.HF_HOME
            )
            
            logger.info(f"Loading vision model (Threads: {config.N_THREADS})...")
            
            self.chat_handler = Llava15ChatHandler(
                clip_model_path=mmproj_path,
                verbose=False
            )
            
            self.model = Llama(
                model_path=model_path,
                chat_handler=self.chat_handler,
                n_ctx=config.VISION_MODEL_CTX,
                n_threads=config.N_THREADS,
                n_batch=config.VISION_MODEL_BATCH,
                logits_all=True,
                verbose=False
            )
            logger.info("✓ Vision model loaded successfully")
            
        except Exception as e:
            logger.error(f"Failed to initialize vision model: {e}")
            raise
    
    def is_ready(self) -> bool:
        return self.model is not None and self.chat_handler is not None
    
    # UPDATED METHOD
    async def analyze_image(
        self,
        image_data: bytes,
        prompt: str,
        temperature: float = 0.6,
        max_tokens: int = 512,
        return_json: bool = False  # Added parameter
    ) -> Dict[str, Any]:
        """
        Analyze an image with a text prompt
        """
        if not self.is_ready():
            raise RuntimeError("Vision model not initialized")
        
        try:
            # Convert image bytes to base64 data URI
            image_b64 = base64.b64encode(image_data).decode('utf-8')
            
            # Validate image
            image = Image.open(io.BytesIO(image_data))
            logger.info(f"Processing image: {image.size} | Format: {image.format}")
            
            # Modify prompt if return_json is requested
            # Note: For LLaVA/Vision models, it is often safer to append the system instruction 
            # to the user text rather than a separate system role message.
            final_prompt = prompt
            if return_json:
                final_prompt += (
                    "\n\nYou are a strict JSON generator. "
                    "Convert the output into valid JSON format. "
                    "Output strictly in markdown code blocks like ```json ... ```. "
                    "Do not add conversational filler."
                )

            # Create vision message format
            messages = [
                {
                    "role": "user",
                    "content": [
                        {"type": "image_url", "image_url": {"url": f"data:image/jpeg;base64,{image_b64}"}},
                        {"type": "text", "text": final_prompt}
                    ]
                }
            ]
            
            logger.info(f"Analyzing image with prompt: {prompt[:50]}... | JSON: {return_json}")
            
            response = self.model.create_chat_completion(
                messages=messages,
                temperature=temperature,
                max_tokens=max_tokens
            )

            content_text = response['choices'][0]['message']['content']
            
            # Logic for return_json
            if return_json:
                extracted_data = extract_json_from_content(content_text)
                return {
                    "status": "success",
                    "data": extracted_data,
                    "image_info": {
                        "size": list(image.size),
                        "format": image.format
                    },
                    "usage": response.get('usage', {})
                }

            # Standard return
            return {
                "status": "success",
                "image_info": {
                    "size": list(image.size),
                    "format": image.format,
                    "mode": image.mode
                },
                "prompt": prompt,
                "response": content_text,
                "usage": response.get('usage', {})
            }
            
        except Exception as e:
            logger.error(f"Error analyzing image: {e}")
            raise
    
    async def cleanup(self) -> None:
        if self.model:
            del self.model
            self.model = None
        if self.chat_handler:
            del self.chat_handler
            self.chat_handler = None
        logger.info("Vision model unloaded")

# Global instance
vision_service = VisionService()