import json
from aiohttp import web
from config.logger import setup_logging
from core.utils.util import get_vision_url, is_valid_image_file
from core.utils.vllm import create_instance
import base64

TAG = __name__

# 设置最大文件大小为5MB
MAX_FILE_SIZE = 5 * 1024 * 1024


class VisionHandler:
    def __init__(self, config: dict):
        self.config = config
        self.logger = setup_logging()

    def _create_error_response(self, message: str) -> dict:
        """创建统一的错误响应格式"""
        return {"success": False, "message": message}

    async def handle_post(self, request):
        """处理 MCP Vision POST 请求"""
        try:
            # 获取请求头信息
            device_id = request.headers.get("Device-Id", "")
            client_id = request.headers.get("Client-Id", "")
            self.logger.bind(tag=TAG).debug(f"Device-Id: {device_id}")
            self.logger.bind(tag=TAG).debug(f"Client-Id: {client_id}")

            # 解析multipart/form-data请求
            reader = await request.multipart()

            # 读取question字段
            question_field = await reader.next()
            if question_field is None:
                raise ValueError("缺少问题字段")
            question = await question_field.text()
            self.logger.bind(tag=TAG).debug(f"Question: {question}")

            # 读取图片文件
            image_field = await reader.next()
            if image_field is None:
                raise ValueError("缺少图片文件")

            # 读取图片数据
            image_data = await image_field.read()
            if not image_data:
                raise ValueError("图片数据为空")

            # 检查文件大小
            if len(image_data) > MAX_FILE_SIZE:
                raise ValueError(
                    f"图片大小超过限制，最大允许{MAX_FILE_SIZE/1024/1024}MB"
                )

            # 检查文件格式
            if not is_valid_image_file(image_data):
                raise ValueError(
                    "不支持的文件格式，请上传有效的图片文件（支持JPEG、PNG、GIF、BMP、TIFF、WEBP格式）"
                )

            # 将图片转换为base64编码
            image_base64 = base64.b64encode(image_data).decode("utf-8")

            vllm_config = self.config["VLLM"]["ChatGLMVLLM"]
            provider = create_instance("openai", vllm_config)
            response = provider.response(question, image_base64)

            return_json = {
                "success": True,
                "result": response,
            }

            response = web.Response(
                text=json.dumps(return_json, separators=(",", ":")),
                content_type="application/json",
            )
        except ValueError as e:
            self.logger.bind(tag=TAG).error(f"MCP Vision POST请求异常: {e}")
            return_json = self._create_error_response(str(e))
            response = web.Response(
                text=json.dumps(return_json, separators=(",", ":")),
                content_type="application/json",
            )
        except Exception as e:
            self.logger.bind(tag=TAG).error(f"MCP Vision POST请求异常: {e}")
            return_json = self._create_error_response("处理请求时发生错误")
            response = web.Response(
                text=json.dumps(return_json, separators=(",", ":")),
                content_type="application/json",
            )
        finally:
            self._add_cors_headers(response)
            return response

    async def handle_get(self, request):
        """处理 MCP Vision GET 请求"""
        try:
            vision_explain = get_vision_url(self.config)
            message = f"MCP Vision 接口运行正常，视觉解释接口地址是：{vision_explain}"
            response = web.Response(text=message, content_type="text/plain")
        except Exception as e:
            self.logger.bind(tag=TAG).error(f"MCP Vision GET请求异常: {e}")
            return_json = self._create_error_response("服务器内部错误")
            response = web.Response(
                text=json.dumps(return_json, separators=(",", ":")),
                content_type="application/json",
            )
        finally:
            self._add_cors_headers(response)
            return response

    def _add_cors_headers(self, response):
        """添加CORS头信息"""
        response.headers["Access-Control-Allow-Headers"] = (
            "client-id, content-type, device-id"
        )
        response.headers["Access-Control-Allow-Credentials"] = "true"
        response.headers["Access-Control-Allow-Origin"] = "*"