from datetime import datetime, timedelta
from fastapi import APIRouter, Depends, Query
from sqlalchemy import select, func, and_, case
from app.core.database import async_session
from app.models.event_log import EventLog
from app.api.deps import require_admin

router = APIRouter(dependencies=[Depends(require_admin)])


@router.get("/summary")
async def get_summary(days: int = Query(default=7, ge=1, le=365)):
    """
    Сводная статистика за последние N дней.
    Возвращает по каждой группе:
    - total_commands -- общее количество команд
    - toggles_on / toggles_off -- включений / выключений
    - scenes / colors / brightness / temperature -- количество смен режимов
    - estimated_hours -- оценка часов работы (по парам on/off)
    """
    since = (datetime.now() - timedelta(days=days)).isoformat()

    async with async_session() as session:
        # Все события за период
        result = await session.execute(
            select(EventLog)
            .where(EventLog.timestamp >= since)
            .order_by(EventLog.timestamp)
        )
        events = result.scalars().all()

    # Агрегация по target_id
    stats = {}
    # Для подсчёта часов работы: запоминаем время последнего включения
    last_on = {}

    for ev in events:
        tid = ev.target_id
        if tid not in stats:
            stats[tid] = {
                "target_id": tid,
                "target_type": ev.target_type,
                "total_commands": 0,
                "toggles_on": 0,
                "toggles_off": 0,
                "scenes": 0,
                "colors": 0,
                "brightness": 0,
                "temperature": 0,
                "estimated_hours": 0.0,
                "by_user": {},
            }

        s = stats[tid]
        s["total_commands"] += 1

        # Счётчик по пользователям
        u = ev.key_name
        s["by_user"][u] = s["by_user"].get(u, 0) + 1

        # Классификация
        if ev.action == "toggle_on":
            s["toggles_on"] += 1
            last_on[tid] = ev.timestamp
        elif ev.action == "toggle_off":
            s["toggles_off"] += 1
            # Считаем время работы
            if tid in last_on:
                try:
                    t_on = datetime.fromisoformat(last_on[tid])
                    t_off = datetime.fromisoformat(ev.timestamp)
                    delta = (t_off - t_on).total_seconds() / 3600.0
                    # Защита от мусора: макс 24 часа за один сеанс
                    if 0 < delta < 24:
                        s["estimated_hours"] += delta
                except (ValueError, TypeError):
                    pass
                del last_on[tid]
        elif ev.action == "scene":
            s["scenes"] += 1
        elif ev.action == "color":
            s["colors"] += 1
        elif ev.action == "brightness":
            s["brightness"] += 1
        elif ev.action == "temperature":
            s["temperature"] += 1

    # Округляем часы
    for s in stats.values():
        s["estimated_hours"] = round(s["estimated_hours"], 1)

    return {
        "period_days": days,
        "since": since,
        "groups": list(stats.values()),
    }


@router.get("/log")
async def get_log(limit: int = Query(default=50, ge=1, le=500)):
    """Последние N событий (для просмотра лога)."""
    async with async_session() as session:
        result = await session.execute(
            select(EventLog).order_by(EventLog.timestamp.desc()).limit(limit)
        )
        events = result.scalars().all()

    return [
        {
            "id": ev.id,
            "timestamp": ev.timestamp,
            "key_name": ev.key_name,
            "action": ev.action,
            "target_type": ev.target_type,
            "target_id": ev.target_id,
            "params": ev.params,
        }
        for ev in events
    ]