from __future__ import annotations

from .shared import *

def _utc_now_naive() -> datetime:
    return now_cn_naive()

async def _ensure_project_signal_link(
    db: AsyncSession,
    *,
    tenant_id: int,
    project_id: int,
    signal_id: int,
    link_type: str = "related",
) -> None:
    existing = (
        await db.execute(
            select(ProjectSignalLink.id).where(
                and_(
                    ProjectSignalLink.tenant_id == int(tenant_id),
                    ProjectSignalLink.project_id == int(project_id),
                    ProjectSignalLink.signal_id == int(signal_id),
                )
            ).limit(1)
        )
    ).scalar_one_or_none()
    if existing is not None:
        return
    db.add(
        ProjectSignalLink(
            tenant_id=int(tenant_id),
            project_id=int(project_id),
            signal_id=int(signal_id),
            link_type=link_type,
            relevance_score=1.0,
        )
    )

def _parse_related_users(raw_value: Any) -> List[str]:
    """兼容 involved_user_ids 的 list / json-string / 单值字符串。"""
    if raw_value is None:
        return []
    if isinstance(raw_value, list):
        return [str(item) for item in raw_value if item is not None]
    if isinstance(raw_value, (bytes, bytearray)):
        raw_value = raw_value.decode("utf-8", errors="ignore")
    if isinstance(raw_value, str):
        text = raw_value.strip()
        if not text:
            return []
        try:
            parsed = json.loads(text)
        except (TypeError, ValueError, json.JSONDecodeError):
            if "," in text:
                return [v.strip() for v in text.split(",") if v.strip()]
            return [text]
        if isinstance(parsed, list):
            return [str(item) for item in parsed if item is not None]
        if parsed is None:
            return []
        return [str(parsed)]
    return [str(raw_value)]