from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session
from typing import List, Optional
from backend.database import get_db
from backend.models import User, UserRole
from backend.schemas import UserOut, UserCreate, UserUpdate
from backend.routers.auth import get_current_user, get_admin_user

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

@router.get("", response_model=List[UserOut])
def get_all_users(db: Session = Depends(get_db), current_user: User = Depends(get_current_user)):
    return db.query(User).order_by(User.id.asc()).all()

@router.post("", response_model=UserOut)
def create_user(user_in: UserCreate, db: Session = Depends(get_db), admin: User = Depends(get_admin_user)):
    existing = db.query(User).filter(User.email == user_in.email).first()
    if existing:
        raise HTTPException(status_code=400, detail="User with this email already exists")
    
    avatar = user_in.avatar_url or f"https://api.dicebear.com/7.x/bottts/svg?seed={user_in.email}"
    new_user = User(
        email=user_in.email,
        name=user_in.name,
        google_id=user_in.google_id,
        avatar_url=avatar,
        role=user_in.role,
        weekly_star_quota=user_in.weekly_star_quota
    )
    db.add(new_user)
    db.commit()
    db.refresh(new_user)
    return new_user

@router.get("/{user_id}", response_model=UserOut)
def get_user_by_id(user_id: int, db: Session = Depends(get_db), current_user: User = Depends(get_current_user)):
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    return user

@router.patch("/{user_id}", response_model=UserOut)
def update_user(user_id: int, user_in: UserUpdate, db: Session = Depends(get_db), current_user: User = Depends(get_current_user)):
    # Regular users can only update their own avatar and name. Admins can update role, quota, active status.
    if current_user.role != UserRole.ADMIN.value and current_user.id != user_id:
        raise HTTPException(status_code=403, detail="Cannot edit another user's account")
    
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    
    if user_in.name is not None:
        user.name = user_in.name
    if user_in.avatar_url is not None:
        user.avatar_url = user_in.avatar_url
    
    # Admin-only fields
    if current_user.role == UserRole.ADMIN.value:
        if user_in.role is not None:
            user.role = user_in.role
        if user_in.weekly_star_quota is not None:
            user.weekly_star_quota = user_in.weekly_star_quota
        if user_in.is_active is not None:
            user.is_active = user_in.is_active

    db.commit()
    db.refresh(user)
    return user

@router.delete("/{user_id}")
def delete_user(user_id: int, db: Session = Depends(get_db), admin: User = Depends(get_admin_user)):
    if admin.id == user_id:
        raise HTTPException(status_code=400, detail="Cannot delete your own admin account")
    
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    
    db.delete(user)
    db.commit()
    return {"message": "User deleted successfully", "id": user_id}