"""
知你客服 Agent 代理（方式一：App 后端代理）
调用低代码平台执行 API：登录拿 Token -> 创建执行 -> 轮询状态 -> 取 output_data 作为回复。
"""
import time
import logging
import requests

logger = logging.getLogger(__name__)

# 内存缓存：platform_token, token_expires_at (简单实现，生产可用 Redis)
_platform_token = None
_token_expires_at = 0
TOKEN_BUFFER_SECONDS = 300  # 提前 5 分钟视为过期


def _get_platform_token(base_url, username, password):
    """登录平台获取 access_token，带简单内存缓存。"""
    global _platform_token, _token_expires_at
    if _platform_token and time.time() < _token_expires_at - TOKEN_BUFFER_SECONDS:
        return _platform_token
    url = f"{base_url.rstrip('/')}/api/v1/auth/login"
    try:
        # 8037 使用 form 登录；先 form，失败再试 JSON
        r = requests.post(
            url,
            data={"username": username, "password": password},
            headers={"Content-Type": "application/x-www-form-urlencoded"},
            timeout=10,
        )
        if r.status_code == 422:
            logger.warning("平台登录 form 返回 422，尝试 JSON: %s", r.text[:200] if r.text else "")
            r = requests.post(
                url,
                json={"username": username, "password": password},
                headers={"Content-Type": "application/json"},
                timeout=10,
            )
        if r.status_code == 401:
            logger.warning("平台登录仍 401，请检查 PLATFORM_USERNAME/PLATFORM_PASSWORD 及平台账号: %s", r.text[:200] if r.text else "")
            raise ValueError(
                "知你客服平台登录失败(401)，请确认 8037 服务已启动且 PLATFORM_USERNAME/PLATFORM_PASSWORD 正确"
            )
        r.raise_for_status()
        data = r.json()
        token = data.get("access_token")
        if not token:
            raise ValueError("平台登录响应无 access_token")
        _platform_token = token
        _token_expires_at = time.time() + 3600  # 假设 1 小时有效
        return token
    except requests.exceptions.HTTPError as e:
        if e.response is not None and e.response.status_code == 401:
            raise ValueError(
                "知你客服平台登录失败(401)，请确认 8037 服务已启动且账号配置正确"
            )
        logger.exception("平台登录失败: %s", e)
        raise
    except ValueError:
        raise
    except Exception as e:
        logger.exception("平台登录失败: %s", e)
        raise


def _create_execution(base_url, token, agent_id, input_data):
    """POST /api/v1/executions"""
    url = f"{base_url.rstrip('/')}/api/v1/executions"
    r = requests.post(
        url,
        json={"agent_id": agent_id, "input_data": input_data},
        headers={"Authorization": f"Bearer {token}", "Content-Type": "application/json"},
        timeout=15,
    )
    r.raise_for_status()
    return r.json()


def _get_execution_status(base_url, token, execution_id):
    """GET /api/v1/executions/{id}/status"""
    url = f"{base_url.rstrip('/')}/api/v1/executions/{execution_id}/status"
    r = requests.get(url, headers={"Authorization": f"Bearer {token}"}, timeout=10)
    r.raise_for_status()
    return r.json()


def _get_execution(base_url, token, execution_id):
    """GET /api/v1/executions/{id}"""
    url = f"{base_url.rstrip('/')}/api/v1/executions/{execution_id}"
    r = requests.get(url, headers={"Authorization": f"Bearer {token}"}, timeout=10)
    r.raise_for_status()
    return r.json()


def _extract_reply(output_data):
    """从 output_data 中提取回复文本（知你客服 End 节点输出结构以实际为准）。"""
    if output_data is None:
        return ""
    if isinstance(output_data, str):
        return output_data
    for key in ("reply", "content", "output", "text", "message", "result"):
        if key in output_data and output_data[key]:
            v = output_data[key]
            return v if isinstance(v, str) else str(v)
    if isinstance(output_data, dict):
        for v in output_data.values():
            if isinstance(v, str) and v.strip():
                return v
    return str(output_data)


def chat_with_agent(base_url, username, password, agent_id, message, user_id, poll_interval=0.8, poll_timeout=60):
    """
    与知你客服对话：创建执行 -> 轮询直到 completed/failed -> 返回回复文本。
    """
    token = _get_platform_token(base_url, username, password)
    input_data = {"query": message, "user_id": user_id or "default"}
    exec_body = _create_execution(base_url, token, agent_id, input_data)
    execution_id = exec_body.get("id")
    if not execution_id:
        raise ValueError("创建执行未返回 id")
    status = exec_body.get("status", "pending")
    deadline = time.time() + poll_timeout
    status_body = None
    while status in ("pending", "running") and time.time() < deadline:
        time.sleep(poll_interval)
        status_body = _get_execution_status(base_url, token, execution_id)
        status = status_body.get("status", status)
    if status != "completed":
        detail = _get_execution(base_url, token, execution_id)
        err = detail.get("error_message") or (status_body or {}).get("error_message") or "执行未完成或失败"
        raise ValueError(err)
    detail = _get_execution(base_url, token, execution_id)
    output_data = detail.get("output_data")
    return _extract_reply(output_data)