"""
Beacon Service - 蓝牙信标管理服务
Provides CRUD operations for Bluetooth beacon configuration.
"""

from datetime import datetime, timezone

from sqlalchemy import func, select, or_
from sqlalchemy.ext.asyncio import AsyncSession

from app.models import BeaconConfig
from app.schemas import BeaconConfigCreate, BeaconConfigUpdate


async def get_beacons(
    db: AsyncSession,
    page: int = 1,
    page_size: int = 20,
    status_filter: str | None = None,
    search: str | None = None,
) -> tuple[list[BeaconConfig], int]:
    """Get paginated beacon list with optional filters."""
    query = select(BeaconConfig)
    count_query = select(func.count(BeaconConfig.id))

    if status_filter:
        query = query.where(BeaconConfig.status == status_filter)
        count_query = count_query.where(BeaconConfig.status == status_filter)

    if search:
        like = f"%{search}%"
        cond = or_(
            BeaconConfig.beacon_mac.ilike(like),
            BeaconConfig.name.ilike(like),
            BeaconConfig.area.ilike(like),
        )
        query = query.where(cond)
        count_query = count_query.where(cond)

    total_result = await db.execute(count_query)
    total = total_result.scalar() or 0

    offset = (page - 1) * page_size
    query = query.order_by(BeaconConfig.created_at.desc()).offset(offset).limit(page_size)
    result = await db.execute(query)
    return list(result.scalars().all()), total


async def get_beacon(db: AsyncSession, beacon_id: int) -> BeaconConfig | None:
    result = await db.execute(
        select(BeaconConfig).where(BeaconConfig.id == beacon_id)
    )
    return result.scalar_one_or_none()


async def get_beacon_by_mac(db: AsyncSession, mac: str) -> BeaconConfig | None:
    result = await db.execute(
        select(BeaconConfig).where(BeaconConfig.beacon_mac == mac)
    )
    return result.scalar_one_or_none()


async def create_beacon(db: AsyncSession, data: BeaconConfigCreate) -> BeaconConfig:
    beacon = BeaconConfig(**data.model_dump())
    db.add(beacon)
    await db.flush()
    await db.refresh(beacon)
    return beacon


async def update_beacon(
    db: AsyncSession, beacon_id: int, data: BeaconConfigUpdate
) -> BeaconConfig | None:
    beacon = await get_beacon(db, beacon_id)
    if beacon is None:
        return None

    update_data = data.model_dump(exclude_unset=True)
    for key, value in update_data.items():
        setattr(beacon, key, value)
    from app.config import now_cst
    beacon.updated_at = now_cst()

    await db.flush()
    await db.refresh(beacon)
    return beacon


async def delete_beacon(db: AsyncSession, beacon_id: int) -> bool:
    beacon = await get_beacon(db, beacon_id)
    if beacon is None:
        return False
    await db.delete(beacon)
    await db.flush()
    return True