from datetime import datetime, timedelta

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

from app.models.activity import Activity
from app.models.match import Match
from app.models.user import User


async def get_dashboard_data(session: AsyncSession) -> dict:
    total_users = int((await session.execute(select(func.count(User.id)))).scalar() or 0)
    total_matches = int((await session.execute(select(func.count(Match.id)))).scalar() or 0)
    total_activities = int((await session.execute(select(func.count(Activity.id)))).scalar() or 0)
    pending_audit = int(
        (await session.execute(select(func.count(User.id)).where(User.audit_status == 1))).scalar() or 0
    )
    ongoing_activities = int(
        (await session.execute(select(func.count(Activity.id)).where(Activity.status.in_([1, 3])))).scalar() or 0
    )

    seven_days_ago = datetime.now() - timedelta(days=7)
    active_users_7d = int(
        (await session.execute(select(func.count(User.id)).where(User.updated_at >= seven_days_ago))).scalar() or 0
    )

    match_rate = round(total_matches / total_users, 3) if total_users else 0

    user_trend = []
    match_trend = []
    for offset in range(6, -1, -1):
        day_start = (datetime.now() - timedelta(days=offset)).replace(hour=0, minute=0, second=0, microsecond=0)
        day_end = day_start + timedelta(days=1)

        user_count = int(
            (await session.execute(
                select(func.count(User.id)).where(User.created_at >= day_start, User.created_at < day_end)
            )).scalar()
            or 0
        )
        match_count = int(
            (await session.execute(
                select(func.count(Match.id)).where(Match.matched_at >= day_start, Match.matched_at < day_end)
            )).scalar()
            or 0
        )

        day_label = day_start.strftime('%Y-%m-%d')
        user_trend.append({"date": day_label, "count": user_count})
        match_trend.append({"date": day_label, "count": match_count})

    return {
        "total_users": total_users,
        "active_users_7d": active_users_7d,
        "pending_audit": pending_audit,
        "total_activities": total_activities,
        "ongoing_activities": ongoing_activities,
        "total_matches": total_matches,
        "match_rate": match_rate,
        "user_trend": user_trend,
        "match_trend": match_trend,
    }