"""Perplexity 호출 — 이 프로젝트에서 Perplexity 로 나가는 **유일한 통로**."""
import json
from dataclasses import dataclass

import httpx

from config.server_configs import external_api_config

API_URL = "https://api.perplexity.ai/chat/completions"

DEFAULT_MODEL = "sonar"

# 첫 구조화 출력 요청은 스키마 준비에 10~30초가 걸린다 — 그 시간을 포함한 값이다.
DEFAULT_TIMEOUT = httpx.Timeout(90.0, connect=10.0)
DEFAULT_MAX_TOKENS = 2048


class PerplexityError(RuntimeError):
    """Perplexity 호출 실패."""


class PerplexityNotConfigured(PerplexityError):
    """PERPLEXITY_API_KEY 미설정 — 이 어댑터만 비활성."""


def is_configured() -> bool:
    """키가 설정돼 있는지."""
    return bool((external_api_config.perplexity_api_key or "").strip())


@dataclass
class Usage:
    """호출 1회의 실제 사용량·비용."""

    input_tokens: int = 0
    output_tokens: int = 0
    num_search_queries: int = 0
    cost: float = 0.0


def read_usage(payload: dict) -> Usage:
    """응답의 usage 를 읽는다."""
    u = payload.get("usage") or {}
    cost_field = u.get("cost")
    if isinstance(cost_field, dict):
        cost = cost_field.get("total_cost")
    else:
        cost = cost_field
    return Usage(
        input_tokens=int(u.get("prompt_tokens") or 0),
        output_tokens=int(u.get("completion_tokens") or 0),
        num_search_queries=int(u.get("num_search_queries") or 0),
        cost=float(cost) if isinstance(cost, (int, float)) else 0.0,
    )


async def call(body: dict, *, client: httpx.AsyncClient | None = None) -> dict:
    """LLM 이 실제로 불리는 지점."""
    api_key = (external_api_config.perplexity_api_key or "").strip()
    if not api_key:
        raise PerplexityNotConfigured("PERPLEXITY_API_KEY 미설정 — 채널 발견을 건너뛴다")

    headers = {"Authorization": f"Bearer {api_key}", "Content-Type": "application/json"}
    owns_client = client is None
    http = client or httpx.AsyncClient(timeout=DEFAULT_TIMEOUT)
    try:
        resp = await http.post(API_URL, json=body, headers=headers)
    except httpx.TimeoutException as ex:
        raise PerplexityError(f"Perplexity 타임아웃: {ex}") from ex
    except httpx.HTTPError as ex:
        raise PerplexityError(f"Perplexity 호출 실패: {type(ex).__name__}: {ex}") from ex
    finally:
        if owns_client:
            await http.aclose()

    if resp.status_code != 200:
        raise PerplexityError(f"Perplexity 응답 오류: status={resp.status_code} body={resp.text[:200]}")

    try:
        payload = resp.json()
    except (json.JSONDecodeError, ValueError) as ex:
        raise PerplexityError(f"Perplexity 응답 JSON 파싱 실패: {ex}") from ex
    if not isinstance(payload, dict):
        raise PerplexityError("Perplexity 응답이 객체가 아니다")
    return payload