# -*- coding: utf-8 -*-
"""同步流式响应垫片（音频分段透传）。
"""



class _SyncStreamResponse:
    """同步流式响应包装（把 aiohttp 的异步流按需拉成同步迭代）。

    供流式下载使用：worker 是同步线程，这里经 core.async_bridge 在后台事件循环
    逐块取数据，避免引入 requests 依赖（Flask 已删除、requests 已移出依赖）。
    """

    def __init__(self, url: str, timeout: float):
        from core import async_bridge
        self._bridge = async_bridge
        self._url = url
        self._timeout = timeout
        self._agent = None
        self.status = 0
        self.headers: dict[str, str] = {}
        self._resp = None

    def __enter__(self):
        self._agent = self._bridge.run_sync(self._open())
        self.status = self._agent[0]
        self.headers = self._agent[1]
        return self

    async def _open(self):
        from core.http_client import client
        resp = await client.open('GET', self._url, headers={
            'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 '
                          '(KHTML, like Gecko) Safari/537.36',
            'Referer': 'https://music.163.com/',
        }, timeout=self._timeout)
        return resp.status, dict(resp.headers), resp

    def iter_content(self, chunk_size: int = 256 * 1024):
        assert self._agent is not None
        resp = self._agent[2]
        it = resp.content.iter_chunked(chunk_size)
        while True:
            try:
                chunk = self._bridge.run_sync(it.__anext__())
            except StopAsyncIteration:
                break
            yield chunk

    def __exit__(self, *exc):
        if self._agent is not None and self._agent[2] is not None:
            try:
                self._agent[2].close()
            except Exception:
                pass
        return False


def _stream_open(url: str, timeout: float = 60) -> _SyncStreamResponse:
    """打开同步可迭代的流式响应（见 _SyncStreamResponse）。"""
    return _SyncStreamResponse(url, timeout)