# app/services/seaweedfs_service.py

import httpx
from fastapi import UploadFile
from app.core.biz_exception import BizLogicError
from app.core.logger import logger


class SeaweedFSService:
    MASTER_URL = "http://127.0.0.1:9333"  # SeaweedFS master 地址
    DOWNLOAD_GATEWAY = "http://45.137.220.138:8888/api/resource/download_file"

    @classmethod
    async def upload(cls, file: UploadFile):
        """上传文件到 SeaweedFS（异步）"""
        try:
            async with httpx.AsyncClient(timeout=10) as client:
                # 1️⃣ 获取 volume
                assign_resp = await client.get(f"{cls.MASTER_URL}/dir/assign")
                assign_resp.raise_for_status()
                assign_data = assign_resp.json()

                fid = assign_data["fid"]
                public_url = assign_data["publicUrl"]

                upload_url = f"http://{public_url}/{fid}"
                download_url = f"{cls.DOWNLOAD_GATEWAY}?fid={fid}"

                # 2️⃣ 上传文件
                files = {
                    "file": (
                        file.filename,
                        await file.read(),
                        file.content_type,
                    )
                }

                upload_resp = await client.post(upload_url, files=files)

                if upload_resp.status_code == 201:
                    return {
                        "fid": fid,
                        "url": download_url,
                    }

                raise BizLogicError(f"file upload error: {upload_resp.text}")

        except Exception as e:
            logger.exception("SeaweedFS upload failed")
            raise BizLogicError(f"file upload exception: {e}")

    @classmethod
    async def get(cls, fid: str):
        """根据 fid 读取文件（异步）"""
        try:
            volume_id = fid.split(",")[0]

            async with httpx.AsyncClient(timeout=10) as client:
                lookup_resp = await client.get(
                    f"{cls.MASTER_URL}/dir/lookup",
                    params={"volumeId": volume_id},
                )
                lookup_resp.raise_for_status()
                data = lookup_resp.json()

                if not data.get("locations"):
                    return None

                public_url = data["locations"][0]["publicUrl"]
                file_url = f"http://{public_url}/{fid}"

                file_resp = await client.get(file_url)
                if file_resp.status_code == 200:
                    return (
                        file_resp.content,
                        file_resp.headers.get(
                            "Content-Type", "application/octet-stream"
                        ),
                    )

                return None

        except Exception as e:
            logger.exception(f"SeaweedFS get failed, reason={e}")
            return None

    @classmethod
    async def delete(cls, fid: str) -> bool:
        """删除文件（异步）"""
        try:
            volume_id = fid.split(",")[0]

            async with httpx.AsyncClient(timeout=10) as client:
                lookup_resp = await client.get(
                    f"{cls.MASTER_URL}/dir/lookup",
                    params={"volumeId": volume_id},
                )
                lookup_resp.raise_for_status()
                data = lookup_resp.json()

                if not data.get("locations"):
                    return False

                public_url = data["locations"][0]["publicUrl"]
                delete_url = f"http://{public_url}/{fid}"

                del_resp = await client.delete(delete_url)
                return del_resp.status_code == 202

        except Exception as e:
            logger.exception(f"SeaweedFS delete failed, reason={e}")
            return False