"""
Base agent client — OpenAI-compatible wrapper around AMD's free Model API.

Same architecture as v1 — the agent layer is intentionally model-agnostic
so it can be swapped to any OpenAI-compatible endpoint. SDXL-specific
prompt engineering lives in prompt_engineer.py.
"""
from __future__ import annotations

import logging
from dataclasses import dataclass
from typing import Any, Dict, List, Optional

from openai import OpenAI

from config.settings import settings

log = logging.getLogger(__name__)


@dataclass
class AgentResponse:
    content: str
    model: str
    ok: bool
    error: Optional[str] = None
    raw: Optional[Dict[str, Any]] = None


class AgentClient:
    """Thin wrapper around OpenAI SDK pointed at AMD's free API."""

    def __init__(
        self,
        model: Optional[str] = None,
        fallback_model: Optional[str] = None,
        api_key: Optional[str] = None,
        base_url: Optional[str] = None,
        temperature: float = 0.7,
        max_tokens: int = 1024,
    ) -> None:
        self.model = model or settings.amd_agent_model
        self.fallback_model = fallback_model or settings.amd_agent_fallback
        self.temperature = temperature
        self.max_tokens = max_tokens
        self._api_key = api_key or settings.amd_api_key
        self._base_url = base_url or settings.amd_base_url
        self._client: Optional[OpenAI] = None

        if not self._api_key:
            log.warning(
                "AMD_MODEL_API_KEY not set — agent layer disabled. "
                "Core generation is unaffected."
            )

    @property
    def enabled(self) -> bool:
        return bool(self._api_key)

    def _get_client(self) -> OpenAI:
        if self._client is None:
            self._client = OpenAI(api_key=self._api_key, base_url=self._base_url)
        return self._client

    def chat(
        self,
        system_prompt: str,
        user_prompt: str,
        temperature: Optional[float] = None,
        max_tokens: Optional[int] = None,
    ) -> AgentResponse:
        if not self.enabled:
            return AgentResponse(
                content="", model=self.model, ok=False,
                error="Agent API key not configured",
            )

        messages = [
            {"role": "system", "content": system_prompt},
            {"role": "user", "content": user_prompt},
        ]
        return self._call_with_fallback(messages, temperature, max_tokens)

    def _call_with_fallback(
        self,
        messages: List[Dict[str, str]],
        temperature: Optional[float],
        max_tokens: Optional[int],
    ) -> AgentResponse:
        models_to_try = [self.model]
        if self.fallback_model and self.fallback_model != self.model:
            models_to_try.append(self.fallback_model)

        client = self._get_client()
        last_error: Optional[str] = None

        for model in models_to_try:
            try:
                resp = client.chat.completions.create(
                    model=model,
                    messages=messages,
                    temperature=temperature if temperature is not None else self.temperature,
                    max_tokens=max_tokens or self.max_tokens,
                )
                content = resp.choices[0].message.content or ""
                return AgentResponse(
                    content=content.strip(),
                    model=model,
                    ok=True,
                    raw={"usage": resp.usage.model_dump() if resp.usage else None},
                )
            except Exception as exc:
                last_error = f"{type(exc).__name__}: {exc}"
                log.warning("Agent call to %s failed: %s", model, last_error)
                continue

        return AgentResponse(
            content="", model=self.model, ok=False,
            error=last_error or "Unknown error",
        )