import json
import logging
import time
from datetime import datetime
from typing import Any, Dict, Optional

import requests
from requests import Response

from app.extensions import db
from flask import current_app

from app.models import ApiCallLog, ApiConfig

logger = logging.getLogger(__name__)


def _parse_json_field(raw: Optional[str]) -> Optional[Dict[str, Any]]:
    if not raw:
        return None
    try:
        return json.loads(raw)
    except json.JSONDecodeError:
        return None


def execute_api(api_config: ApiConfig) -> None:
    """
    根据配置调用 API，带重试，并将每次尝试都记录为日志（保留历史）。
    """
    request_time = datetime.utcnow()
    headers = _parse_json_field(api_config.headers) or {}
    params = _parse_json_field(api_config.query_params) or {}
    data = api_config.body
    try:
        json_body = json.loads(api_config.body) if api_config.body else None
    except json.JSONDecodeError:
        json_body = None

    retries = max(api_config.retry_times, 0)
    delay = max(api_config.retry_interval_seconds, 1)
    timeout = max(api_config.timeout_seconds, 1)
    attempt = 0
    total_attempts = retries + 1
    last_error: Optional[str] = None

    while attempt < total_attempts:
        last_response: Optional[Response] = None
        start_ts = time.time()
        attempt += 1
        try:
            last_response = requests.request(
                method=api_config.http_method,
                url=api_config.url,
                headers=headers,
                params=params,
                data=None if json_body is not None else data,
                json=json_body,
                timeout=timeout,
            )
            if 200 <= last_response.status_code < 300:
                last_error = None
            else:
                body_snippet = (last_response.text or "")[:200]
                last_error = f"Non-2xx status: {last_response.status_code}, body: {body_snippet}"
        except requests.RequestException as exc:
            last_error = str(exc)

        duration_ms = int((time.time() - start_ts) * 1000)
        success = last_error is None

        log_entry = ApiCallLog(
            api_id=api_config.id,
            request_time=request_time,
            response_time=datetime.utcnow(),
            success=success,
            http_status_code=last_response.status_code if last_response else None,
            error_message=(f"[第{attempt}次尝试/{total_attempts}] {last_error}" if last_error else None),
            response_body=(last_response.text[:2000] if last_response and last_response.text else None),
            duration_ms=duration_ms,
        )
        db.session.add(log_entry)
        try:
            db.session.commit()
        except Exception:
            logger.exception("Failed to persist ApiCallLog for api_id=%s", api_config.id)
            db.session.rollback()

        if success:
            break
        if attempt < total_attempts:
            time.sleep(delay)

    if last_error:
        logger.warning("API call failed for api_id=%s error=%s", api_config.id, last_error)


def execute_api_by_id(api_id: int, app=None) -> None:
    """
    Load ApiConfig by id and execute within app context (for scheduler threads).
    """
    app_obj = app or current_app._get_current_object()
    with app_obj.app_context():
        config = ApiConfig.query.get(api_id)
        if not config:
            logger.error("ApiConfig not found for id=%s", api_id)
            return
        execute_api(config)