converter.py

"""
Message converter for OpenAI format to Cursor Agent prompt
"""

from typing import List, Dict, Any


def messages_to_prompt(messages: List[Dict[str, Any]]) -> str:
    """
    Convert OpenAI-style messages array to a single prompt string.
    
    Example:
        [
            {"role": "system", "content": "You are helpful"},
            {"role": "user", "content": "Hello"},
            {"role": "assistant", "content": "Hi there!"},
            {"role": "user", "content": "How are you?"}
        ]
        ->
        "System: You are helpful
        
        User: Hello
        
        Assistant: Hi there!
        
        User: How are you?"
    """
    if not messages:
        return ""
    
    # If only one user message, return content directly
    if len(messages) == 1 and messages[0].get("role") == "user":
        return messages[0].get("content", "")
    
    parts = []
    for msg in messages:
        role = msg.get("role", "user")
        content = msg.get("content", "")
        
        if role == "system":
            parts.append(f"System: {content}")
        elif role == "user":
            parts.append(f"User: {content}")
        elif role == "assistant":
            parts.append(f"Assistant: {content}")
        else:
            parts.append(f"{role.capitalize()}: {content}")
    
    return "\n\n".join(parts)


def cursor_response_to_openai(
    cursor_result: Dict[str, Any],
    model: str,
    request_id: str = None
) -> Dict[str, Any]:
    """
    Convert Cursor Agent JSON response to OpenAI-compatible format.
    
    Cursor response:
        {
            "type": "result",
            "subtype": "success",
            "result": "Hello!",
            "session_id": "...",
            "request_id": "..."
        }
    
    OpenAI response:
        {
            "id": "chatcmpl-xxx",
            "object": "chat.completion",
            "model": "sonnet-4.5",
            "choices": [{"message": {"role": "assistant", "content": "Hello!"}}],
            "usage": {...}
        }
    """
    import time
    
    content = cursor_result.get("result", "")
    is_error = cursor_result.get("is_error", False)
    
    if is_error:
        content = f"Error: {content}"
    
    return {
        "id": f"chatcmpl-{request_id or cursor_result.get('request_id', 'unknown')}",
        "object": "chat.completion",
        "created": int(time.time()),
        "model": model,
        "choices": [
            {
                "index": 0,
                "message": {
                    "role": "assistant",
                    "content": content
                },
                "finish_reason": "stop"
            }
        ],
        "usage": {
            "prompt_tokens": 0,
            "completion_tokens": 0,
            "total_tokens": 0
        }
    }