# -*- coding: utf-8 -*-
"""API客户端"""
import requests
from urllib3.util.retry import Retry
from requests.adapters import HTTPAdapter

class APIClient:
    """HTTP API客户端"""
    
    def __init__(self, base_url: str, token: str = None, timeout: int = 20,
                 retry_max: int = 3, headers_extra: dict = None):
        self.base_url = base_url.rstrip("/")
        self.token = token
        self.timeout = timeout
        self.retry_max = retry_max
        self.headers_extra = headers_extra or {}
        self._session = None
    
    def _get_session(self):
        """获取或创建会话"""
        if self._session is None:
            self._session = requests.Session()
            
            retries = max(0, int(self.retry_max) - 1)
            retry = Retry(
                total=None,
                connect=retries,
                read=retries,
                status=retries,
                allowed_methods=frozenset(["GET"]),
                status_forcelist=(429, 500, 502, 503, 504),
                backoff_factor=1.0,
                respect_retry_after_header=True,
                raise_on_status=False,
            )
            
            adapter = HTTPAdapter(max_retries=retry)
            self._session.mount("http://", adapter)
            self._session.mount("https://", adapter)
            
            if self.headers_extra:
                self._session.headers.update(self.headers_extra)
        
        return self._session
    
    def get(self, endpoint: str, params: dict = None) -> dict:
        """执行GET请求"""
        url = f"{self.base_url}/{endpoint.lstrip('/')}"
        headers = {"Authorization": self.token} if self.token else {}
        headers.update(self.headers_extra)
        
        sess = self._get_session()
        resp = sess.get(url, headers=headers, params=params, timeout=self.timeout)
        resp.raise_for_status()
        return resp.json()
    
    def get_paginated(self, endpoint: str, params: dict, page_size: int = 200,
                      page_field: str = "pageIndex", size_field: str = "pageSize",
                      data_path: tuple = ("data",), list_key: str = None) -> tuple:
        """分页获取数据"""
        records, pages_meta = [], []
        page = 1
        
        while True:
            p = dict(params)
            p[page_field] = page
            p[size_field] = page_size
            
            obj = self.get(endpoint, p)
            
            # 解析数据路径
            cur = obj
            for k in data_path:
                if isinstance(cur, dict) and k in cur:
                    cur = cur[k]
            
            if list_key:
                cur = (cur or {}).get(list_key, [])
            
            if not isinstance(cur, list):
                cur = []
            
            records.extend(cur)
            
            if len(cur) == 0:
                break
            
            pages_meta.append({"page": page, "request": p, "response": obj})
            
            if len(cur) < page_size:
                break
            
            page += 1
        
        return records, pages_meta