import secrets
from datetime import timedelta, datetime, UTC
from sqlalchemy.orm import Session
from app.models.user_model import User
from app.models.file_model import File
from app.models.user_issue_model import UserIssue
from app.utils.security import hash_password
from app.services.file_delete_service import delete_file_service

def create_user(db: Session, email: str, username: str, password: str) -> tuple[User | None, str | None]:
    if db.query(User).filter(User.email == email).first():
        raise ValueError("email_exists")
        
    if db.query(User).filter(User.username == username).first():
        raise ValueError("username_exists")
    
    hashed_password = hash_password(password)

    raw_token = f"{secrets.randbelow(900000) + 100000}"
    hashed_token = hash_password(raw_token)
    expire_date = datetime.now(UTC) + timedelta(minutes=10)
    
    new_user = User(
        email=email,
        username=username,
        password=hashed_password,
        is_verified=False,
        verification_token_hash=hashed_token,
        verification_token_expire_at=expire_date
    )
    
    db.add(new_user)
    db.commit()
    db.refresh(new_user)
    return new_user, raw_token

def delete_user_account(db: Session, user_id: int):
    # 1. Fetch user
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise ValueError("User not found")

    # 2. Delete all files (and Cloudinary storage media)
    files = db.query(File).filter(File.owner_id == user_id).all()
    for file in files:
        try:
            delete_file_service(db, file.id, user_id)
        except Exception:
            pass # ignore if already deleted or error, ensure we keep deleting others

    # 3. Delete all User Issues
    db.query(UserIssue).filter(UserIssue.user_id == user_id).delete()

    # 4. Delete the user
    db.delete(user)
    db.commit()