from typing import List

from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.orm import Session

from app.db.models import Supplier
from app.db.session import get_db
from app.schemas.inventory import Supplier as SupplierSchema
from app.schemas.inventory import SupplierCreate, SupplierUpdate

router = APIRouter()

@router.get("/", response_model=List[SupplierSchema])
def get_suppliers(skip: int = 0, limit: int = 100, db: Session = Depends(get_db)):
    suppliers = db.query(Supplier).offset(skip).limit(limit).all()
    return suppliers

@router.get("/{supplier_id}", response_model=SupplierSchema)
def get_supplier(supplier_id: int, db: Session = Depends(get_db)):
    supplier = db.query(Supplier).filter(Supplier.id == supplier_id).first()
    if not supplier:
        raise HTTPException(status_code=404, detail="Supplier not found")
    return supplier

@router.post("/", response_model=SupplierSchema)
def create_supplier(supplier: SupplierCreate, db: Session = Depends(get_db)):
    existing_supplier = db.query(Supplier).filter(Supplier.name == supplier.name).first()
    if existing_supplier:
        raise HTTPException(status_code=400, detail="Supplier name already exists")

    db_supplier = Supplier(**supplier.dict())
    db.add(db_supplier)
    db.commit()
    db.refresh(db_supplier)
    return db_supplier

@router.put("/{supplier_id}", response_model=SupplierSchema)
def update_supplier(supplier_id: int, supplier: SupplierUpdate, db: Session = Depends(get_db)):
    db_supplier = db.query(Supplier).filter(Supplier.id == supplier_id).first()
    if not db_supplier:
        raise HTTPException(status_code=404, detail="Supplier not found")

    update_data = supplier.dict(exclude_unset=True)
    for field, value in update_data.items():
        setattr(db_supplier, field, value)

    db.commit()
    db.refresh(db_supplier)
    return db_supplier

@router.delete("/{supplier_id}")
def delete_supplier(supplier_id: int, db: Session = Depends(get_db)):
    db_supplier = db.query(Supplier).filter(Supplier.id == supplier_id).first()
    if not db_supplier:
        raise HTTPException(status_code=404, detail="Supplier not found")

    db.delete(db_supplier)
    db.commit()
    return {"message": "Supplier deleted successfully"}