"""
Main PhoneticSimilaritySystem class for TWGY_V3
"""

from typing import List, Tuple, Optional, Dict, Any
import logging
from pathlib import Path

from .config import SystemConfig, load_default_config
from .exceptions import TWGYError, PhoneticError, SimilarityError


class PhoneticSimilaritySystem:
    """
    Main system class for Chinese phonetic similarity calculation
    
    This is a placeholder implementation that will be expanded with
    the actual phonetic similarity algorithms.
    """
    
    def __init__(self, config: Optional[SystemConfig] = None):
        """
        Initialize the phonetic similarity system
        
        Args:
            config: System configuration, uses default if None
        """
        self.config = config or load_default_config()
        self.logger = logging.getLogger(__name__)
        
        # Initialize components (placeholder)
        self._initialized = False
        self._cache = {}
        
        self.logger.info("PhoneticSimilaritySystem initialized")
    
    def calculate_similarity(self, word1: str, word2: str) -> float:
        """
        Calculate similarity between two words
        
        Args:
            word1: First word
            word2: Second word
            
        Returns:
            Similarity score between 0.0 and 1.0
        """
        if not word1 or not word2:
            return 0.0
        
        if word1 == word2:
            return 1.0
        
        # Placeholder implementation - simple character overlap
        set1, set2 = set(word1), set(word2)
        intersection = len(set1 & set2)
        union = len(set1 | set2)
        
        if union == 0:
            return 0.0
        
        similarity = intersection / union
        
        # Apply length penalty
        length_diff = abs(len(word1) - len(word2))
        max_len = max(len(word1), len(word2))
        length_penalty = 1.0 - (length_diff * self.config.similarity.length_penalty_factor / max_len)
        
        return similarity * max(0.0, length_penalty)
    
    def batch_calculate_similarity(self, word_pairs: List[Tuple[str, str]]) -> List[float]:
        """
        Calculate similarity for multiple word pairs
        
        Args:
            word_pairs: List of (word1, word2) tuples
            
        Returns:
            List of similarity scores
        """
        return [self.calculate_similarity(word1, word2) for word1, word2 in word_pairs]
    
    def find_similar_words(self, target_word: str, 
                          candidates: Optional[List[str]] = None,
                          top_k: int = 10,
                          threshold: float = None) -> List[Dict[str, Any]]:
        """
        Find similar words for a target word
        
        Args:
            target_word: Target word to find similarities for
            candidates: List of candidate words, uses default dictionary if None
            top_k: Number of top results to return
            threshold: Similarity threshold, uses config default if None
            
        Returns:
            List of similar words with similarity scores
        """
        if threshold is None:
            threshold = self.config.similarity.default_threshold
        
        if candidates is None:
            # Placeholder: use a small set of test words
            candidates = ["知道", "資道", "吃飯", "次飯", "是的", "四的"]
        
        # Calculate similarities
        similarities = []
        for candidate in candidates:
            if candidate != target_word:
                similarity = self.calculate_similarity(target_word, candidate)
                if similarity >= threshold:
                    similarities.append({
                        "word": candidate,
                        "similarity": similarity
                    })
        
        # Sort by similarity and return top_k
        similarities.sort(key=lambda x: x["similarity"], reverse=True)
        return similarities[:top_k]
    
    def clear_cache(self):
        """Clear internal cache"""
        self._cache.clear()
        self.logger.info("Cache cleared")
    
    def get_cache_info(self) -> Dict[str, Any]:
        """Get cache information"""
        return {
            "cache_size": len(self._cache),
            "max_cache_size": self.config.performance.cache_size,
            "cache_enabled": self.config.performance.enable_cache
        }
    
    def get_system_info(self) -> Dict[str, Any]:
        """Get system information"""
        return {
            "system": "TWGY_V3",
            "version": "3.0.0",
            "initialized": self._initialized,
            "config": self.config.to_dict(),
            "cache_info": self.get_cache_info()
        }