from fastapi import APIRouter, Depends
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select, func, desc
from app.database import get_db
from app.models.user import User
from app.models.achievement import Achievement, UserAchievement
from app.utils.auth import get_current_user

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

@router.get("")
async def all_achievements(db: AsyncSession = Depends(get_db)):
    achievements = (await db.execute(select(Achievement))).scalars().all()
    return [
        {"id": str(a.id), "name": a.name, "description": a.description, "icon": a.icon,
         "category": a.category, "points": a.points}
        for a in achievements
    ]

@router.get("/mine")
async def my_achievements(user: User = Depends(get_current_user), db: AsyncSession = Depends(get_db)):
    result = await db.execute(
        select(UserAchievement, Achievement)
        .join(Achievement, UserAchievement.achievement_id == Achievement.id)
        .where(UserAchievement.user_id == user.id)
    )
    rows = result.all()
    return [
        {"id": str(ua.id), "achievement": {"id": str(a.id), "name": a.name, "icon": a.icon, "points": a.points},
         "unlocked_at": ua.unlocked_at.isoformat()}
        for ua, a in rows
    ]

@router.get("/leaderboard")
async def leaderboard(db: AsyncSession = Depends(get_db)):
    users = (await db.execute(
        select(User).order_by(desc(User.total_points)).limit(20)
    )).scalars().all()
    return [
        {"name": u.name or u.email.split("@")[0], "points": u.total_points, "streak": u.streak_days}
        for u in users
    ]