from __future__ import annotations
import os
import asyncio
import logging
from typing import List, Dict, Any, Optional

import httpx

from queue_helper import QueueManager

logger = logging.getLogger(__name__)

# -------------------------------------------------------------
# Config voor onderliggende LLM-backend
# -------------------------------------------------------------
# Dit is NIET jouw eigen /v1/chat/completions endpoint,
# maar de *echte* model-backend (bijv. Ollama, vLLM, Mistral server, etc.).
LLM_API_BASE = os.getenv("LLM_API_BASE", "http://127.0.0.1:11434")
LLM_DEFAULT_MODEL = os.getenv("LLM_MODEL", "gpt-4o-mini")
LLM_REQUEST_TIMEOUT = float(os.getenv("LLM_REQUEST_TIMEOUT", "120"))

# Deze wordt in app.py gezet via init_llm_client(...)
LLM_QUEUE: QueueManager | None = None


def init_llm_client(queue: QueueManager) -> None:
    """
    Koppel de globale LLM_QUEUE aan de QueueManager uit app.py.
    Deze MOET je in app.py één keer aanroepen.
    """
    global LLM_QUEUE
    LLM_QUEUE = queue
    logger.info("llm_client: LLM_QUEUE gekoppeld via init_llm_client.")


def _sync_model_infer(payload: Dict[str, Any]) -> Dict[str, Any]:
    """
    Synchronous call naar de echte LLM-backend.
    Dit is de functie die je in app.py gebruikt bij het maken van de QueueManager.
    """
    url = f"{LLM_API_BASE.rstrip('/')}/v1/chat/completions"
    try:
        with httpx.Client(timeout=LLM_REQUEST_TIMEOUT) as client:
            resp = client.post(url, json=payload)
            resp.raise_for_status()
            return resp.json()
    except Exception as exc:
        logger.exception("LLM backend call failed: %s", exc)
        return {
            "object": "chat.completion",
            "choices": [{
                "index": 0,
                "finish_reason": "error",
                "message": {
                    "role": "assistant",
                    "content": f"[LLM-fout] {exc}",
                },
            }],
            "usage": {
                "prompt_tokens": 0,
                "completion_tokens": 0,
                "total_tokens": 0,
            },
        }


async def _llm_call(
    messages: List[Dict[str, str]],
    *,
    stream: bool = False,
    temperature: float = 0.2,
    top_p: float = 0.9,
    max_tokens: Optional[int] = None,
    model: Optional[str] = None,
    **extra: Any,
) -> Dict[str, Any]:
    """
    Centrale helper voor tools/agents/smart_rag/repo-agent.

    Belangrijk:
    - Gebruikt de *bestaande* QueueManager uit app.py (via init_llm_client).
    - Stuurt jobs in de agent-queue (lagere prioriteit dan users).
    - GEEN wachtrij-meldingen ("u bent #...") voor deze interne calls.
    """
    if stream:
        # In deze agent gebruiken we geen streaming.
        raise NotImplementedError("_llm_call(stream=True) wordt momenteel niet ondersteund.")

    if LLM_QUEUE is None:
        # Hard fail: dan weet je meteen dat init_llm_client nog niet is aangeroepen.
        raise RuntimeError("LLM_QUEUE is niet geïnitialiseerd. Roep init_llm_client(...) aan in app.py")

    payload: Dict[str, Any] = {
        "model": model or LLM_DEFAULT_MODEL,
        "messages": messages,
        "stream": False,
        "temperature": float(temperature),
        "top_p": float(top_p),
    }
    if max_tokens is not None:
        payload["max_tokens"] = int(max_tokens)

    payload.update(extra)

    loop = asyncio.get_running_loop()

    try:
        # request_agent_sync blokkeert → naar threadpool
        response: Dict[str, Any] = await loop.run_in_executor(
            None, lambda: LLM_QUEUE.request_agent_sync(payload)
        )
        return response
    except Exception as exc:
        logger.exception("_llm_call via agent-queue failed: %s", exc)
        return {
            "object": "chat.completion",
            "choices": [{
                "index": 0,
                "finish_reason": "error",
                "message": {
                    "role": "assistant",
                    "content": f"[LLM-queue-fout] {exc}",
                },
            }],
            "usage": {
                "prompt_tokens": 0,
                "completion_tokens": 0,
                "total_tokens": 0,
            },
        }