backend/openrouter_improved.py

"""OpenRouter API client with improved error handling and retry logic."""

import httpx
import asyncio
from typing import List, Dict, Any, Optional
from .config_improved import (
    OPENROUTER_API_KEY, 
    OPENROUTER_API_URL,
    DEFAULT_TIMEOUT,
    MAX_RETRIES,
    RETRY_DELAY
)


async def query_model(
    model: str, 
    messages: List[Dict[str, str]], 
    timeout: float = DEFAULT_TIMEOUT,
    max_retries: int = MAX_RETRIES
) -> Optional[Dict[str, Any]]:
    """
    Query a single model via OpenRouter API with retry logic.

    Args:
        model: OpenRouter model identifier (e.g., "openai/gpt-4o")
        messages: List of message dicts with 'role' and 'content'
        timeout: Request timeout in seconds
        max_retries: Maximum number of retry attempts

    Returns:
        Response dict with 'content' and optional 'reasoning_details', or None if failed
    """
    headers = {
        "Authorization": f"Bearer {OPENROUTER_API_KEY}",
        "Content-Type": "application/json",
        "X-Title": "LLM Council",
    }

    payload = {
        "model": model,
        "messages": messages,
    }

    for attempt in range(max_retries + 1):
        try:
            async with httpx.AsyncClient(timeout=timeout) as client:
                response = await client.post(OPENROUTER_API_URL, headers=headers, json=payload)
                response.raise_for_status()

                data = response.json()
                message = data["choices"][0]["message"]

                return {
                    "content": message.get("content"),
                    "reasoning_details": message.get("reasoning_details")
                }

        except httpx.TimeoutException as e:
            print(f"⏱️ Timeout querying model {model} (attempt {attempt + 1}/{max_retries + 1}): {e}")
            if attempt < max_retries:
                await asyncio.sleep(RETRY_DELAY * (attempt + 1))  # Exponential backoff
                continue
            return None
            
        except httpx.HTTPStatusError as e:
            print(f"🚫 HTTP error querying model {model}: {e.response.status_code} - {e.response.text}")
            # Don't retry on 4xx errors (client errors)
            if 400 <= e.response.status_code < 500:
                return None
            # Retry on 5xx errors (server errors)
            if attempt < max_retries:
                await asyncio.sleep(RETRY_DELAY * (attempt + 1))
                continue
            return None
            
        except Exception as e:
            print(f"❌ Error querying model {model} (attempt {attempt + 1}/{max_retries + 1}): {e}")
            if attempt < max_retries:
                await asyncio.sleep(RETRY_DELAY)
                continue
            return None

    return None


async def query_model_stream(
    model: str, 
    messages: List[Dict[str, str]], 
    timeout: float = DEFAULT_TIMEOUT
):
    """
    Query a model via OpenRouter API and stream the response.
    Yields content chunks as they arrive.
    
    Args:
        model: OpenRouter model identifier
        messages: List of message dicts with 'role' and 'content'
        timeout: Request timeout in seconds
        
    Yields:
        Content chunks as strings
    """
    headers = {
        "Authorization": f"Bearer {OPENROUTER_API_KEY}",
        "Content-Type": "application/json",
        "X-Title": "LLM Council",
    }

    payload = {
        "model": model, 
        "messages": messages, 
        "stream": True
    }

    import json

    try:
        async with httpx.AsyncClient(timeout=timeout) as client:
            async with client.stream("POST", OPENROUTER_API_URL, headers=headers, json=payload) as response:
                response.raise_for_status()
                async for line in response.aiter_lines():
                    if line.startswith("data: "):
                        data_str = line[6:]
                        if data_str.strip() == "[DONE]":
                            break
                        try:
                            data = json.loads(data_str)
                            delta = data["choices"][0]["delta"]
                            content = delta.get("content")
                            if content:
                                yield content
                        except json.JSONDecodeError:
                            pass
                        except KeyError:
                            pass
                            
    except httpx.TimeoutException as e:
        print(f"⏱️ Timeout streaming model {model}: {e}")
        yield f"\n\n[Error: Request timed out after {timeout}s]"
        
    except httpx.HTTPStatusError as e:
        print(f"🚫 HTTP error streaming model {model}: {e.response.status_code}")
        yield f"\n\n[Error: HTTP {e.response.status_code}]"
        
    except Exception as e:
        print(f"❌ Error streaming model {model}: {e}")
        yield f"\n\n[Error: {str(e)}]"


async def query_models_parallel(
    models: List[str], 
    messages: List[Dict[str, str]],
    timeout: float = DEFAULT_TIMEOUT
) -> Dict[str, Optional[Dict[str, Any]]]:
    """
    Query multiple models in parallel with individual error handling.

    Args:
        models: List of OpenRouter model identifiers
        messages: List of message dicts to send to each model
        timeout: Request timeout in seconds

    Returns:
        Dict mapping model identifier to response dict (or None if failed)
    """
    import asyncio

    print(f"🚀 Querying {len(models)} models in parallel...")
    
    # Create tasks for all models
    tasks = [query_model(model, messages, timeout=timeout) for model in models]

    # Wait for all to complete
    responses = await asyncio.gather(*tasks, return_exceptions=True)

    # Map models to their responses, handling exceptions
    result = {}
    for model, response in zip(models, responses):
        if isinstance(response, Exception):
            print(f"❌ Model {model} raised exception: {response}")
            result[model] = None
        else:
            result[model] = response
            status = "✅" if response else "❌"
            print(f"{status} Model {model} completed")

    successful = sum(1 for r in result.values() if r is not None)
    print(f"📊 {successful}/{len(models)} models responded successfully")
    
    return result