from PDAPI import *
import os
import json
import hashlib

RESOURCE_ROOT = os.path.join(os.path.abspath(os.path.join(os.getcwd(), "resource")))
TEMP_ROOT = os.path.join(RESOURCE_ROOT, ".tmp")


__metadata__ = {
    "methods": ["POST"],
    "blueprint": "GERP",
    "permission": 3.0,
    "attributes": [],
    "limit": "120 per minute",
}

def HandleRequest(_CleanedData):
    current_user = UGM.GetELTUser()
    if not current_user:
        return {"code": 401, "msg": "未登录"}, 401

    upload_id = flask.request.form.get("uploadId", "").strip()
    chunk_index = flask.request.form.get("chunkIndex", "").strip()
    chunk_md5 = flask.request.form.get("chunkMD5", "").strip()

    if not upload_id or not chunk_index:
        return {"code": 1, "msg": "缺少uploadId或chunkIndex"}, 400

    try:
        chunk_index = int(chunk_index)
    except ValueError:
        return {"code": 1, "msg": "chunkIndex必须为整数"}, 400

    temp_dir = os.path.join(TEMP_ROOT, upload_id)
    if not os.path.isdir(temp_dir):
        return {"code": 1, "msg": "上传会话不存在或已过期"}, 404

    meta_path = os.path.join(temp_dir, "meta.json")
    if not os.path.exists(meta_path):
        return {"code": 1, "msg": "上传元数据不存在"}, 404

    with open(meta_path, "r", encoding="utf-8") as f:
        meta = json.load(f)

    if chunk_index < 0 or chunk_index >= meta["totalChunks"]:
        return {"code": 1, "msg": f"分片索引超出范围(0-{meta['totalChunks']-1})"}, 400

    if 'chunk' not in flask.request.files:
        return {"code": 1, "msg": "未找到分片数据"}, 400

    chunk_file = flask.request.files['chunk']
    chunk_data = chunk_file.read()

    if chunk_md5:
        actual_md5 = hashlib.md5(chunk_data).hexdigest()
        if actual_md5 != chunk_md5:
            return {"code": 1, "msg": f"分片校验失败: 期望{chunk_md5}, 实际{actual_md5}"}, 400

    chunk_path = os.path.join(temp_dir, str(chunk_index))
    with open(chunk_path, "wb") as f:
        f.write(chunk_data)

    if chunk_index not in meta["receivedChunks"]:
        meta["receivedChunks"].append(chunk_index)
        with open(meta_path, "w", encoding="utf-8") as f:
            json.dump(meta, f, ensure_ascii=False)

    return {
        "code": 0,
        "msg": "分片上传成功",
        "data": {
            "uploadId": upload_id,
            "chunkIndex": chunk_index,
            "chunkSize": len(chunk_data),
            "receivedChunks": sorted(meta["receivedChunks"]),
            "totalChunks": meta["totalChunks"],
        }
    }, 200