"""Permission delegation routes — CRUD API for temporary permission handovers."""

from __future__ import annotations

import uuid

from fastapi import APIRouter, Depends, HTTPException, Query, status
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.db import get_db
from app.deps import require_permission
from app.schemas.delegation import DelegationCreate, DelegationUpdate
from app.services import delegation_service

router = APIRouter(prefix="/api/v1/delegations", tags=["delegations"])


@router.get("")
async def list_delegations(
    direction: str = Query("all", pattern="^(from|to|all)$"),
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(require_permission("delegations:read")),
):
    """List delegations for the current user."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    user_id = uuid.UUID(current_user["user_id"])
    items = await delegation_service.list_delegations(db, tenant_id, user_id, direction)
    return {"items": items, "total": len(items)}


@router.post("", status_code=status.HTTP_201_CREATED)
async def create_delegation(
    body: DelegationCreate,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(require_permission("delegations:write")),
):
    """Create a new permission delegation."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    from_user_id = uuid.UUID(current_user["user_id"])
    try:
        return await delegation_service.create_delegation(
            db,
            tenant_id,
            from_user_id=from_user_id,
            to_user_id=uuid.UUID(body.to_user_id),
            start_at=body.start_at,
            end_at=body.end_at,
            scope=body.scope,
        )
    except ValueError as e:
        raise HTTPException(status_code=400, detail=str(e)) from e


@router.put("/{delegation_id}")
async def update_delegation(
    delegation_id: str,
    body: DelegationUpdate,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(require_permission("delegations:write")),
):
    """Update an existing delegation."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    try:
        return await delegation_service.update_delegation(
            db,
            tenant_id,
            delegation_id,
            start_at=body.start_at,
            end_at=body.end_at,
            scope=body.scope,
            active=body.active,
        )
    except ValueError as e:
        raise HTTPException(status_code=404, detail=str(e)) from e


@router.delete("/{delegation_id}", status_code=status.HTTP_204_NO_CONTENT)
async def delete_delegation(
    delegation_id: str,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(require_permission("delegations:write")),
):
    """Delete a delegation."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    try:
        await delegation_service.delete_delegation(db, tenant_id, delegation_id)
    except ValueError as e:
        raise HTTPException(status_code=404, detail=str(e)) from e


@router.get("/active")
async def check_active_delegation(
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(require_permission("delegations:read")),
):
    """Check if the current user has any active delegations."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    user_id = uuid.UUID(current_user["user_id"])
    is_active = await delegation_service.is_delegation_active(db, user_id, tenant_id)
    active_list = await delegation_service.get_active_delegations(db, user_id, tenant_id)
    return {
        "is_active": is_active,
        "active_delegations": active_list,
        "count": len(active_list),
    }