from typing import List, Optional
from fastapi import APIRouter, Depends, HTTPException, Query
from sqlmodel import Session, select
from database import get_session
from models import Attendance, User, Show
from schemas import AttendanceCreate, AttendanceRead
from auth import get_current_user
from services.gamification import award_xp, check_and_award_badges, update_streak, XP_REWARDS

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

@router.post("/", response_model=AttendanceRead)
def mark_attendance(
    attendance: AttendanceCreate, 
    session: Session = Depends(get_session),
    current_user: User = Depends(get_current_user)
):
    # Check if already attended
    existing = session.exec(
        select(Attendance)
        .where(Attendance.user_id == current_user.id)
        .where(Attendance.show_id == attendance.show_id)
    ).first()
    
    if existing:
        # Update notes if provided, or just return existing
        if attendance.notes:
            existing.notes = attendance.notes
            session.add(existing)
            session.commit()
            session.refresh(existing)
        return existing

    db_attendance = Attendance(**attendance.model_dump(), user_id=current_user.id)
    session.add(db_attendance)
    
    # Award XP for marking attendance
    new_xp, level_up = award_xp(session, current_user, XP_REWARDS["attendance_add"], "attendance")
    update_streak(session, current_user)
    new_badges = check_and_award_badges(session, current_user)
    
    session.commit()
    session.refresh(db_attendance)
    return db_attendance

@router.delete("/{show_id}")
def remove_attendance(
    show_id: int,
    session: Session = Depends(get_session),
    current_user: User = Depends(get_current_user)
):
    attendance = session.exec(
        select(Attendance)
        .where(Attendance.user_id == current_user.id)
        .where(Attendance.show_id == show_id)
    ).first()
    
    if not attendance:
        raise HTTPException(status_code=404, detail="Attendance not found")
        
    session.delete(attendance)
    session.commit()
    return {"ok": True}

@router.get("/me", response_model=List[AttendanceRead])
def get_my_attendance(
    session: Session = Depends(get_session),
    current_user: User = Depends(get_current_user)
):
    return session.exec(select(Attendance).where(Attendance.user_id == current_user.id)).all()

@router.get("/show/{show_id}", response_model=List[AttendanceRead])
def get_show_attendance(
    show_id: int,
    session: Session = Depends(get_session),
    offset: int = 0,
    limit: int = 100
):
    return session.exec(
        select(Attendance)
        .where(Attendance.show_id == show_id)
        .offset(offset)
        .limit(limit)
    ).all()


@router.get("/me/stats")
def get_my_attendance_stats(
    session: Session = Depends(get_session),
    current_user: User = Depends(get_current_user)
):
    """Get attendance statistics grouped by band"""
    from models import Vertical
    
    attendances = session.exec(
        select(Attendance).where(Attendance.user_id == current_user.id)
    ).all()
    
    total = len(attendances)
    by_vertical = {}
    years = set()
    
    for a in attendances:
        show = session.get(Show, a.show_id)
        if not show:
            continue
            
        if show.date:
            years.add(show.date.year)
        
        vertical = session.get(Vertical, show.vertical_id)
        if vertical:
            if vertical.slug not in by_vertical:
                by_vertical[vertical.slug] = {
                    "name": vertical.name,
                    "count": 0
                }
            by_vertical[vertical.slug]["count"] += 1
    
    return {
        "total_shows": total,
        "by_vertical": by_vertical,
        "years_attended": sorted(years, reverse=True),
        "year_count": len(years)
    }