import os
import uvicorn
from fastapi import FastAPI, HTTPException, Depends
from typing import List, Tuple, Optional, Union, Dict, Any
import torch

from config import ServerConfig
from guard_chat import SafeModelPipeline
from pydantic import BaseModel
from dataclasses import dataclass, field
import logging

# Initialize FastAPI app
app = FastAPI(title="Safe Chat Model API")


# Global variables for model and config
pipeline: Optional[SafeModelPipeline] = None
config: Optional[ServerConfig] = None

class ChatRequest(BaseModel):
    messages: List[Dict[str, str]]
    conversation_id: Optional[str] = None  # To track different conversations
    max_new_tokens: Optional[int] = 80
    temperature: Optional[float] = 0.7
    do_sample: Optional[bool] = True
    top_p: Optional[float] = 0.9
    top_k: Optional[int] = 50

class ChatResponse(BaseModel):
    response: str
    input_safety: str
    output_safety: str
    filtered: bool
    conversation_id: str





def get_config():
    """Dependency to get config"""
    if config is None:
        raise HTTPException(status_code=500, detail="Server not initialized")
    return config



@app.post("/update_config")
async def update_config(
    temperature: Optional[float] = None,
    top_k: Optional[int] = None,
    top_p: Optional[float] = None,
    max_new_tokens: Optional[int] = None,
    config: ServerConfig = Depends(get_config)
):
    """Update generation parameters"""
    try:
        if pipeline is None:
            raise HTTPException(status_code=500, detail="Model not initialized")
            
        # Update the configuration
        if temperature is not None:
            pipeline.args.temperature = temperature
        if top_k is not None:
            pipeline.args.top_k = top_k
        if top_p is not None:
            pipeline.args.top_p = top_p
        if max_new_tokens is not None:
            pipeline.args.max_new_tokens = max_new_tokens
        
        return {"message": "Configuration updated successfully"}

        
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

@app.get("/health")
async def health_check():
    """Health check endpoint"""
    if pipeline is None or config is None:
        raise HTTPException(status_code=503, detail="Server not fully initialized")
    return {"status": "healthy"}


@app.on_event("startup")
async def startup_event():
    """Initialize the server on startup"""
    global pipeline, config
    
    try:
        # Load config from YAML
        config_path = os.getenv("CONFIG_PATH", "config.yaml")
        config = ServerConfig.from_yaml(config_path)
        
        # Initialize pipeline with config
        pipeline = SafeModelPipeline(
            model_args=config.to_chat_arguments(),
            system_prompt=config.system_prompt,
            max_history_tokens=config.max_history_tokens
        )
        
    except Exception as e:
        print(f"Error initializing server: {str(e)}")
        raise

@app.post("/chat", response_model=ChatResponse)
async def chat_endpoint(request: ChatRequest):
    """Chat endpoint that handles conversation and calls the safe model pipeline"""
    logging.info(f"Received request: {request}")  # Log the incoming request
    
    if pipeline is None:
        raise HTTPException(status_code=500, detail="Model not initialized")
    
    try:
        # Validate request
        if not request.messages:
            raise HTTPException(status_code=400, detail="No messages provided")
        
        logging.info(f"Processing messages: {request.messages}")  # Log the messages
        
        # Call the safe model pipeline's generate_response method
        try:
            response = await pipeline.generate_response(request)
            logging.info(f"Generated response: {response}")  # Log the response
        except Exception as e:
            logging.error(f"Pipeline error: {str(e)}", exc_info=True)
            raise HTTPException(status_code=500, detail=f"Pipeline error: {str(e)}")
        
        # If response is None or invalid, raise an error
        if not response:
            raise HTTPException(status_code=500, detail="Failed to generate response")
            
        return ChatResponse(
            response=response.response,
            conversation_id=response.conversation_id,
            input_safety=response.input_safety,
            output_safety=response.output_safety,
            filtered=response.filtered
        )
        
    except Exception as e:
        logging.error(f"Error in chat endpoint: {str(e)}", exc_info=True)
        raise HTTPException(status_code=500, detail=str(e))

if __name__ == "__main__":
    import argparse
    
    parser = argparse.ArgumentParser()
    parser.add_argument("--host", type=str, default="0.0.0.0", 
                       help="Host to run the server on")
    parser.add_argument("--port", type=int, default=8000, 
                       help="Port to run the server on")
    parser.add_argument("--config", type=str, default="config.yaml", 
                       help="Path to config file")
    
    args = parser.parse_args()
    
    # Set config path environment variable
    os.environ["CONFIG_PATH"] = args.config
    
    # Run the server
    uvicorn.run(app, host=args.host, port=args.port)