from sqlalchemy.orm import Session
from typing import List, Optional
from fastapi import HTTPException
from app.models.contractor import Contractor
from app.schemas.contractor import ContractorCreate, ContractorUpdate

class ContractorService:
    def __init__(self, db: Session):
        self._db = db

    def get_contractors(
        self, 
        parent_id: Optional[int] = None, 
        only_parents: bool = False,
        is_active: Optional[bool] = None
    ) -> List[Contractor]:
        query = self._db.query(Contractor)
        if only_parents:
            query = query.filter(Contractor.parent_id == None)
        elif parent_id is not None:
            query = query.filter(Contractor.parent_id == parent_id)
        
        if is_active is not None:
            query = query.filter(Contractor.is_active == is_active)
        return query.all()

    def get_contractor(self, contractor_id: int) -> Contractor:
        db_contractor = self._db.query(Contractor).filter(Contractor.id == contractor_id).first()
        if not db_contractor:
            raise HTTPException(status_code=404, detail="Contractor not found")
        return db_contractor

    def create_contractor(self, contractor: ContractorCreate) -> Contractor:
        db_contractor = Contractor(**contractor.model_dump())
        self._db.add(db_contractor)
        self._db.commit()
        self._db.refresh(db_contractor)
        return db_contractor

    def update_contractor(self, contractor_id: int, contractor: ContractorUpdate) -> Contractor:
        db_contractor = self.get_contractor(contractor_id)
        
        update_data = contractor.model_dump(exclude_unset=True)
        for key, value in update_data.items():
            setattr(db_contractor, key, value)
        
        self._db.commit()
        self._db.refresh(db_contractor)
        return db_contractor

    def delete_contractor(self, contractor_id: int):
        db_contractor = self.get_contractor(contractor_id)
        self._db.delete(db_contractor)
        self._db.commit()
        return None