utils/recommend.py

import json
import os
from typing import Dict, Any, Optional
import logging

# Setup logging
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

# Global variables
_condition_data = {}
_last_load_time = 0

def _load_condition_data() -> Dict[str, Any]:
    """Load skin condition data from JSON file with proper error handling"""
    json_path = 'data/skin_conditions.json'
    
    try:
        # Get file modification time to check for changes
        mtime = os.path.getmtime(json_path)
        
        # If we've already loaded and file hasn't changed, return cached data
        global _condition_data, _last_load_time
        if _condition_data and mtime <= _last_load_time:
            return _condition_data
        
        # Load and parse JSON file
        with open(json_path, encoding='utf-8') as f:
            data = json.load(f)
        
        # Index data by lowercase condition name for faster lookups
        condition_map = {}
        for entry in data:
            condition = entry.get("condition", "").strip().lower()
            if condition:  # Only add entries with a valid condition name
                condition_map[condition] = entry
        
        # Update cache
        _condition_data = condition_map
        _last_load_time = mtime
        logger.info(f"Loaded {len(condition_map)} skin conditions from {json_path}")
        return condition_map
        
    except FileNotFoundError:
        logger.error(f"Skin conditions file not found: {json_path}")
        return {}
    except json.JSONDecodeError as e:
        logger.error(f"Invalid JSON in skin conditions file: {e}")
        return {}
    except Exception as e:
        logger.error(f"Error loading skin conditions: {e}")
        return {}

def get_recommended_products(condition_query: str) -> Dict[str, Any]:
    """
    Get recommended products for a given skin condition.
    
    Args:
        condition_query: The skin condition to look up
        
    Returns:
        Dictionary containing condition info and product recommendations,
        or empty dict if no match found
    """
    if not condition_query:
        return {}
    
    # Standardize the query
    condition_query = condition_query.strip().lower()
    
    # Load or refresh condition data
    condition_data = _load_condition_data()
    
    # Try exact match first (most reliable)
    if condition_query in condition_data:
        return condition_data[condition_query]
    
    # If exact match fails, try to find the closest match
    # This is a fallback for when condition names might have slight variations
    for cond_name, entry in condition_data.items():
        # Check if query is a substring of a condition or vice versa
        if condition_query in cond_name or cond_name in condition_query:
            return entry
    
    # No match found
    logger.warning(f"No recommendations found for condition: {condition_query}")
    return {}