from typing import Generic, Type, TypeVar, List, Any, Optional
from sqlalchemy.orm import Session
from sqlalchemy import select

T = TypeVar("T")

class BaseRepository(Generic[T]):
    def __init__(self, model: Type[T]):
        self.model = model

    def get_by_id(self, db: Session, id: Any) -> Optional[T]:
        return db.get(self.model, id)

    def get_all(self, db: Session, skip: int = 0, limit: int = 100) -> List[T]:
        stmt = select(self.model).offset(skip).limit(limit)
        return list(db.execute(stmt).scalars().all())

    def create(self, db: Session, entity: T) -> T:
        db.add(entity)
        db.commit()
        db.refresh(entity)
        return entity

    def update(self, db: Session, entity: T) -> T:
        db.add(entity)
        db.commit()
        db.refresh(entity)
        return entity

    def delete(self, db: Session, entity: T) -> None:
        db.delete(entity)
        db.commit()