# Enhanced Embedding Service with Rate Limiting Handling
"""
Enhanced embedding service that adds basic retry semantics around the local
embedding generator. Since embeddings are fully local, rate-limiting metadata is
largely informational but retained for compatibility.
"""

import logging
import time
from typing import Any, Dict, List, Optional

from .embedding_service import EmbeddingService
from app.core.config import settings

logger = logging.getLogger(__name__)


class EnhancedEmbeddingService(EmbeddingService):
    """Enhanced embedding service with lightweight retry bookkeeping"""

    def __init__(self, model_name: Optional[str] = None):
        super().__init__(model_name)
        self.rate_limit_tracker = {
            'requests_count': 0,
            'window_start': time.time(),
            'window_size': 60,  # 1 minute window
            'max_requests_per_minute': int(getattr(settings, 'RAG_EMBEDDING_MAX_REQUESTS_PER_MINUTE', 12)),  # Configurable
            'retry_delays': [int(x) for x in getattr(settings, 'RAG_EMBEDDING_RETRY_DELAYS', '1,2,4,8,16').split(',')],  # Exponential backoff
            'delay_between_batches': float(getattr(settings, 'RAG_EMBEDDING_DELAY_BETWEEN_BATCHES', 1.0)),
            'delay_per_request': float(getattr(settings, 'RAG_EMBEDDING_DELAY_PER_REQUEST', 0.5)),
            'last_rate_limit_error': None
        }

    async def get_embeddings_with_retry(self, texts: List[str], max_retries: int = None) -> tuple[List[List[float]], bool]:
        """
        Get embeddings with retry bookkeeping.
        """
        embeddings = await super().get_embeddings(texts)
        success = self.local_model is not None
        if not success:
            logger.warning(
                "Embedding service operating in fallback mode; consider installing the local model %s",
                self.model_name,
            )
        return embeddings, success

    async def get_embedding_stats(self) -> Dict[str, Any]:
        """Get embedding service statistics including rate limiting info"""
        base_stats = await self.get_stats()

        return {
            **base_stats,
            "rate_limit_info": {
                "requests_in_current_window": self.rate_limit_tracker['requests_count'],
                "max_requests_per_minute": self.rate_limit_tracker['max_requests_per_minute'],
                "window_reset_in_seconds": max(0,
                    self.rate_limit_tracker['window_start'] + self.rate_limit_tracker['window_size'] - time.time()
                ),
                "last_rate_limit_error": self.rate_limit_tracker['last_rate_limit_error']
            }
        }


# Global enhanced embedding service instance
enhanced_embedding_service = EnhancedEmbeddingService()