import uuid

import httpx

from config.server_configs import storage_config

# 허용 content-type -> 저장 확장자. 목록 밖이면 업로드 거부.
_EXT_BY_TYPE = {
    "image/jpeg": "jpg",
    "image/png": "png",
    "image/gif": "gif",
    "image/webp": "webp",
}

# 업로드용 공유 클라이언트(연결 풀링).
_shared_client: httpx.AsyncClient | None = None


def _get_client() -> httpx.AsyncClient:
    global _shared_client
    if _shared_client is None or _shared_client.is_closed:
        _shared_client = httpx.AsyncClient(
            timeout=httpx.Timeout(60.0, connect=10.0),
            limits=httpx.Limits(max_keepalive_connections=10, max_connections=20),
        )
    return _shared_client


def is_allowed_image(content_type: str) -> bool:
    return content_type in _EXT_BY_TYPE


async def upload_image(company_id: str, content: bytes, content_type: str) -> str:
    """Azure Blob 에 이미지를 올리고 접근 URL 을 돌려준다.
    blob 경로: <blob_root>/<company_id>/items/<uuid>.<ext>
      — company_id 로 멀티테넌트 격리.
    실패 시 예외를 던진다(호출측에서 IMAGE_UPLOAD_FAILED 처리). 저장값은 SAS 를 뗀 public URL."""
    ext = _EXT_BY_TYPE.get(content_type, "bin")
    blob_path = f"{storage_config.blob_root}/{company_id}/items/{uuid.uuid4().hex}.{ext}"

    base = storage_config.azure_blob_base_url.rstrip("/")
    sas = storage_config.azure_blob_sas_token.strip("?'\"")
    public_url = f"{base}/{blob_path}"
    upload_url = f"{public_url}?{sas}"
    headers = {"Content-Type": content_type, "x-ms-blob-type": "BlockBlob"}

    resp = await _get_client().put(upload_url, content=content, headers=headers)
    if resp.status_code not in (200, 201):
        raise RuntimeError(f"Azure Blob upload failed: status={resp.status_code} body={resp.text[:200]}")
    return public_url