from fastapi import APIRouter, Depends, Query
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select, desc, func
from pydantic import BaseModel
from typing import Optional, List
from datetime import datetime, timedelta, timezone

from app.core.database import get_db
from app.core.security import get_current_user
from app.models.user import User, HealthMetric

router = APIRouter()


class HealthMetricOut(BaseModel):
    id: int
    date: datetime
    resting_hr: Optional[float]
    max_hr_day: Optional[float]
    avg_hr_day: Optional[float]
    hrv_nightly_avg: Optional[float]
    hrv_status: Optional[str]
    hrv_5min_high: Optional[float]
    hrv_5min_low: Optional[float]
    sleep_duration_s: Optional[float]
    sleep_deep_s: Optional[float]
    sleep_light_s: Optional[float]
    sleep_rem_s: Optional[float]
    sleep_awake_s: Optional[float]
    sleep_score: Optional[float]
    sleep_start: Optional[datetime]
    sleep_end: Optional[datetime]
    weight_kg: Optional[float]
    bmi: Optional[float]
    body_fat_pct: Optional[float]
    muscle_mass_kg: Optional[float]
    vo2max: Optional[float]
    fitness_age: Optional[int]
    training_load: Optional[float]
    recovery_time_h: Optional[float]
    avg_stress: Optional[float]
    steps: Optional[int]
    floors_climbed: Optional[int]
    active_calories: Optional[float]
    total_calories: Optional[float]
    spo2_avg: Optional[float]

    class Config:
        from_attributes = True


@router.get("/", response_model=List[HealthMetricOut])
async def list_health_metrics(
    from_date: Optional[datetime] = None,
    to_date: Optional[datetime] = None,
    limit: int = Query(365, ge=1, le=1000),
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    q = select(HealthMetric).where(HealthMetric.user_id == current_user.id)

    if from_date:
        from_date_naive = from_date.replace(tzinfo=None) if from_date.tzinfo else from_date
        q = q.where(func.date(HealthMetric.date) >= from_date_naive.date())
    if to_date:
        to_date_naive = to_date.replace(tzinfo=None) if to_date.tzinfo else to_date
        q = q.where(func.date(HealthMetric.date) <= to_date_naive.date())

    q = q.order_by(desc(HealthMetric.date)).limit(limit)
    result = await db.execute(q)
    return result.scalars().all()


@router.get("/summary")
async def health_summary(
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    latest_result = await db.execute(
        select(HealthMetric)
        .where(HealthMetric.user_id == current_user.id)
        .order_by(desc(HealthMetric.date))
        .limit(1)
    )
    latest = latest_result.scalar_one_or_none()

    cutoff = (datetime.now(timezone.utc) - timedelta(days=30)).date()
    avg_result = await db.execute(
        select(
            func.avg(HealthMetric.resting_hr).label("avg_resting_hr"),
            func.avg(HealthMetric.hrv_nightly_avg).label("avg_hrv"),
            func.avg(HealthMetric.sleep_duration_s).label("avg_sleep_s"),
            func.avg(HealthMetric.sleep_score).label("avg_sleep_score"),
            func.avg(HealthMetric.avg_stress).label("avg_stress"),
            func.avg(HealthMetric.steps).label("avg_steps"),
            func.avg(HealthMetric.weight_kg).label("avg_weight"),
        ).where(
            HealthMetric.user_id == current_user.id,
            func.date(HealthMetric.date) >= cutoff,
        )
    )
    avgs = avg_result.one()

    return {
        "latest": HealthMetricOut.model_validate(latest) if latest else None,
        "avg_30d": {
            "resting_hr": avgs.avg_resting_hr,
            "hrv": avgs.avg_hrv,
            "sleep_h": (avgs.avg_sleep_s / 3600) if avgs.avg_sleep_s else None,
            "sleep_score": avgs.avg_sleep_score,
            "stress": avgs.avg_stress,
            "steps": avgs.avg_steps,
            "weight_kg": avgs.avg_weight,
        },
    }


@router.put("/manual")
async def add_manual_metric(
    body: dict,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    from fastapi import HTTPException
    date_str = body.get("date")
    if not date_str:
        raise HTTPException(status_code=400, detail="date required")

    metric_date = datetime.fromisoformat(date_str)

    existing = await db.execute(
        select(HealthMetric).where(
            HealthMetric.user_id == current_user.id,
            func.date(HealthMetric.date) == metric_date.date(),
        )
    )
    metric = existing.scalar_one_or_none()

    if metric:
        for key, val in body.items():
            if hasattr(metric, key) and key not in ("id", "user_id"):
                setattr(metric, key, val)
    else:
        metric = HealthMetric(user_id=current_user.id, date=metric_date, **{
            k: v for k, v in body.items()
            if hasattr(HealthMetric, k) and k not in ("id", "user_id")
        })
        db.add(metric)

    await db.commit()
    return {"status": "ok"}