import requests
import time
from typing import Optional
from app.core.config import settings
from app.core.exceptions import (
    UnauthorizedException,
    ForbiddenException,
    BusinessException,
    InternalServerException,
    ErrorMessage,
    StatusCode
)

class request_service:
    def __init__(self):
        """初始化请求服务"""
        self.base_url = settings.JAVA_API_BASE_URL
        self.session = requests.Session()
        self.session.timeout = 80  # 80秒超时
        self.max_retries = 3  # 最大重试次数
        self.retry_delay = 1  # 重试延迟(秒)

    def request(self, method: str, url: str, auth: bool, authorization: Optional[str] = None, 
                source: Optional[str] = None, version: Optional[str] = None, **kwargs) -> any:
        """
        发送请求的核心方法

        参数:
            method: HTTP方法 (GET/POST等)
            url: 请求路径
            auth: 是否需要认证
            authorization: Authorization token
            source: Source 头部，默认为 'customer'
            version: Version 头部，默认为 'V6'
            **kwargs: 其他请求参数

        返回:
            响应数据或文件对象

        异常:
            抛出请求或业务逻辑相关的异常
        """
        # 1. 准备请求头
        headers = self._prepare_headers(auth, authorization, source, version)

        # 2. 处理GET请求的数组参数
        if method.upper() == 'GET' and 'params' in kwargs:
            kwargs['params'] = self._process_array_params(kwargs['params'])

        # 3. 设置请求头
        kwargs['headers'] = headers

        # 4. 发送请求(带重试机制)
        response = self._send_request_with_retry(method, url, **kwargs)

        # 5. 处理响应
        return self._handle_response(response)

    def _prepare_headers(self, auth: bool, authorization: Optional[str] = None,
                         source: Optional[str] = None, version: Optional[str] = None) -> 'dict[str, str]':
        """准备请求头"""
        headers = {
            'Source': source or 'customer',
            'Content-Type': 'application/json',
            'Version': version or 'V6'
        }
        if auth and authorization:
            headers['Authorization'] = authorization
        return headers

    def _process_array_params(self, params: 'dict[str, any]') -> 'dict[str, any]':
        """处理GET请求中的数组参数"""
        processed = {}
        for key, value in params.items():
            if isinstance(value, list):
                processed[key] = ','.join(map(str, value))
            else:
                processed[key] = value
        return processed

    def _handle_response(self, response: requests.Response) -> any:
        """处理响应"""
        # 处理文件类型的响应
        if response.headers.get('requesttype') == 'file':
            return response
        try:
            res = response.json()
        except ValueError:
            raise InternalServerException(detail=ErrorMessage.INVALID_RESPONSE)
        if not res:
            return None
        # 处理业务逻辑错误
        if res.get('code') != 200:
            self._handle_business_error(res)
        return res.get('data')

    def _handle_business_error(self, response_data: 'dict[str, any]'):
        """处理业务逻辑错误，直接使用Java服务返回的code和message"""
        error_code = response_data.get('code')
        error_msg = response_data.get('message', '未知系统错误')
        
        # 可接受的错误码，直接返回（不抛出异常）
        if error_code in (-1, 0):
            return
        
        # 根据错误码映射HTTP状态码，但保留原始的code和message
        # 600, 601 -> 401 (未授权)
        if error_code in (600, 601):
            raise UnauthorizedException(
                detail=error_msg,
                code=error_code
            )
        # 403或权限相关 -> 403 (禁止访问)
        elif error_code == 403 or "无该货主权限" in error_msg or "无权限" in error_msg or "没有权限" in error_msg:
            raise ForbiddenException(
                detail=error_msg,
                code=error_code if error_code else StatusCode.FORBIDDEN
            )
        else:
            # 其他所有错误（包括1001等），直接使用原始code和message
            # HTTP状态码使用400，但响应体中的code保留原始值
            raise BusinessException(
                detail=error_msg,
                status_code=400,
                code=error_code
            )

    def _send_request_with_retry(self, method: str, url: str, **kwargs) -> requests.Response:
        """带重试机制的请求发送，打印完整请求数据"""
        last_exception = None
        full_url = f"{self.base_url}{url}"

        for attempt in range(self.max_retries):
            try:
                # 获取headers并确保它是字典
                headers = kwargs.get('headers', {})
                if headers is None:
                    headers = {}
                safe_headers = dict(headers)  # 更安全的方式创建副本
                if 'Authorization' in safe_headers:
                    safe_headers['Authorization'] = 'Bearer ******'

                # 发送请求
                response = self.session.request(method, full_url, **kwargs)
                return response

            except (requests.exceptions.RequestException,
                    requests.exceptions.Timeout) as e:
                last_exception = e
                if attempt < self.max_retries - 1:
                    time.sleep(self.retry_delay)

        raise InternalServerException(
            detail=str(last_exception) if last_exception else ErrorMessage.REQUEST_FAILED
        )