from __future__ import annotations

from .shared import *
from .helpers import _as_dict, _get_project_or_404
from .schemas import LinkSignalRequest

@router.post("/{project_id}/signals/{signal_id}")
async def link_signal_to_project(
    project_id: int,
    signal_id: int,
    body: LinkSignalRequest,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(require_roles("BOSS", "ADMIN")),
):
    tenant_id = int(current_user.tenant_id)
    await _get_project_or_404(db, tenant_id=tenant_id, project_id=project_id)

    signal = (
        await db.execute(
            select(Signal).where(
                and_(
                    Signal.tenant_id == tenant_id,
                    Signal.id == signal_id,
                )
            )
        )
    ).scalar_one_or_none()
    if not signal:
        raise HTTPException(status_code=404, detail="Signal not found")

    existing = (
        await db.execute(
            select(ProjectSignalLink).where(
                and_(
                    ProjectSignalLink.tenant_id == tenant_id,
                    ProjectSignalLink.project_id == project_id,
                    ProjectSignalLink.signal_id == signal_id,
                )
            )
        )
    ).scalar_one_or_none()
    if existing:
        return {
            "id": str(existing.id),
            "project_id": str(existing.project_id),
            "signal_id": str(existing.signal_id),
            "link_type": existing.link_type,
            "relevance_score": float(existing.relevance_score or 0.0),
            "created_at": existing.created_at.isoformat() if existing.created_at else None,
        }

    link = ProjectSignalLink(
        tenant_id=tenant_id,
        project_id=project_id,
        signal_id=signal_id,
        link_type=body.link_type or "related",
        relevance_score=float(body.relevance_score or 1.0),
    )
    db.add(link)
    await db.commit()
    await db.refresh(link)
    await context_cache_service.invalidate_system_context(tenant_id=tenant_id)
    return {
        "id": str(link.id),
        "project_id": str(link.project_id),
        "signal_id": str(link.signal_id),
        "link_type": link.link_type,
        "relevance_score": float(link.relevance_score or 0.0),
        "created_at": link.created_at.isoformat() if link.created_at else None,
    }

@router.delete("/{project_id}/signals/{signal_id}")
async def unlink_signal_from_project(
    project_id: int,
    signal_id: int,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(require_roles("BOSS", "ADMIN")),
):
    tenant_id = int(current_user.tenant_id)
    _ = current_user
    await db.execute(
        delete(ProjectSignalLink).where(
            and_(
                ProjectSignalLink.tenant_id == tenant_id,
                ProjectSignalLink.project_id == project_id,
                ProjectSignalLink.signal_id == signal_id,
            )
        )
    )
    await db.commit()
    await context_cache_service.invalidate_system_context(tenant_id=tenant_id)
    return {"message": "Signal unlinked"}