"""
Claude-Aufruf ueber den lokalen Proxy.

Der Proxy (claude-max-api-proxy) bietet eine OpenAI-kompatible API
unter http://proxy:3456/v1/chat/completions. Wir nutzen non-streaming
mit einem laengeren Timeout — Claude Code spawnt pro Anfrage einen
neuen CLI-Prozess (Cold-Start), das dauert.
"""

from __future__ import annotations

import json
import logging
import os
from pathlib import Path
from typing import List, Optional

import httpx
from pydantic import BaseModel

import metrics

logger = logging.getLogger(__name__)

RUNTIME_CONFIG_FILE = Path("/shared/config/runtime.json")
ENV_MODEL = os.environ.get("BRAIN_MODEL", "claude-sonnet-4")
PROXY_URL = os.environ.get("PROXY_URL", "http://proxy:3456")
PROXY_TIMEOUT_SEC = float(os.environ.get("PROXY_TIMEOUT_SEC", "300"))


def _read_model_from_runtime() -> str:
    """Liest brainModel aus runtime.json. Fallback: ENV BRAIN_MODEL."""
    try:
        if RUNTIME_CONFIG_FILE.exists():
            data = json.loads(RUNTIME_CONFIG_FILE.read_text(encoding="utf-8"))
            m = (data.get("brainModel") or "").strip()
            if m:
                return m
    except Exception as exc:
        logger.warning("runtime.json lesen fehlgeschlagen: %s", exc)
    return ENV_MODEL


DEFAULT_MODEL = _read_model_from_runtime()


class Message(BaseModel):
    role: str  # "system" | "user" | "assistant" | "tool"
    content: Optional[str] = None
    tool_calls: Optional[list] = None
    tool_call_id: Optional[str] = None
    name: Optional[str] = None  # nur fuer role=tool


class ProxyResult(BaseModel):
    content: str = ""
    tool_calls: list = []  # je: {"id", "name", "arguments" (dict)}
    finish_reason: str = ""


class ProxyClient:
    def __init__(self, base_url: str = PROXY_URL, model: str = DEFAULT_MODEL):
        self.base_url = base_url.rstrip("/")
        self.model = model
        # Persistente Client-Connection — vermeidet TCP-Handshake bei jedem Call
        self._client = httpx.Client(timeout=PROXY_TIMEOUT_SEC)

    def chat(self, messages: List[Message], model: Optional[str] = None) -> str:
        """Convenience: einfacher Chat ohne Tools. Gibt nur den Reply-String zurueck."""
        result = self.chat_full(messages, tools=None, model=model)
        if not result.content:
            raise RuntimeError("Proxy lieferte leeren content")
        return result.content

    def chat_full(
        self,
        messages: List[Message],
        tools: Optional[list] = None,
        model: Optional[str] = None,
    ) -> ProxyResult:
        """Full chat — kann Tool-Calls liefern (wenn tools mitgegeben).

        tools-Format ist OpenAI-Style:
          [{"type":"function","function":{"name":..,"description":..,"parameters":{...}}}, ...]
        """
        url = f"{self.base_url}/v1/chat/completions"
        # Pydantic-Dumps mit exclude_none damit role=tool ohne tool_calls geht
        payload = {
            "model": model or self.model,
            "messages": [m.model_dump(exclude_none=True) for m in messages],
        }
        if tools:
            payload["tools"] = tools
        logger.info("Proxy → %s (%d Messages, %d tools, model=%s)",
                    url, len(messages), len(tools or []), payload["model"])
        try:
            r = self._client.post(url, json=payload)
        except httpx.RequestError as exc:
            raise RuntimeError(f"Proxy unreachable: {exc}") from exc
        if r.status_code != 200:
            raise RuntimeError(f"Proxy HTTP {r.status_code}: {r.text[:300]}")
        try:
            data = r.json()
        except Exception as exc:
            raise RuntimeError(f"Proxy invalid JSON: {exc}") from exc

        choices = data.get("choices") or []
        if not choices:
            raise RuntimeError(f"Proxy ohne choices: {str(data)[:300]}")

        msg = choices[0].get("message") or {}
        finish_reason = choices[0].get("finish_reason", "")

        content = msg.get("content") or ""
        if isinstance(content, list):
            content = "".join(
                part.get("text", "") for part in content if isinstance(part, dict) and part.get("type") == "text"
            )

        tool_calls_raw = msg.get("tool_calls") or []
        tool_calls = []
        import json as _json
        for tc in tool_calls_raw:
            fn = tc.get("function") or {}
            args_raw = fn.get("arguments", "{}")
            args: dict
            if isinstance(args_raw, dict):
                args = args_raw
            else:
                try:
                    args = _json.loads(args_raw)
                except Exception:
                    args = {"_raw": args_raw}
            tool_calls.append({
                "id": tc.get("id", ""),
                "name": fn.get("name", ""),
                "arguments": args,
            })

        # Call-Metric anhaengen — Token-Schaetzung fuer Quota-Monitoring
        metrics.log_call(payload["model"], messages, content or "")

        return ProxyResult(content=content or "", tool_calls=tool_calls, finish_reason=finish_reason)

    def close(self):
        try:
            self._client.close()
        except Exception:
            pass