# -*- coding: utf-8 -*-
"""
自定义中间件。
"""
import json


class ResponseCodeMiddleware:
    """为所有 JSON 响应 body 统一注入 code 字段（与 HTTP 状态码一致）。"""

    def __init__(self, get_response):
        self.get_response = get_response

    def __call__(self, request):
        response = self.get_response(request)
        if "application/json" not in response.get("Content-Type", ""):
            return response
        try:
            content = response.content.decode(response.charset or "utf-8")
            data = json.loads(content)
            code = response.status_code
            if isinstance(data, dict):
                if "code" not in data:
                    data["code"] = code
            elif isinstance(data, list):
                data = {"code": code, "data": data}
            else:
                data = {"code": code, "data": data}
            response.content = json.dumps(data, ensure_ascii=False).encode(response.charset or "utf-8")
        except (ValueError, TypeError, UnicodeDecodeError):
            pass
        return response


class CorsMiddleware:
    """简易 CORS 中间件，允许所有跨域请求。"""

    def __init__(self, get_response):
        self.get_response = get_response

    def __call__(self, request):
        response = self.get_response(request)
        response["Access-Control-Allow-Origin"] = "*"
        response["Access-Control-Allow-Methods"] = "GET, POST, PUT, DELETE, OPTIONS"
        response["Access-Control-Allow-Headers"] = "*"
        response["Access-Control-Allow-Credentials"] = "true"
        if request.method == "OPTIONS":
            response.status_code = 200
            response.content = b""
        return response