from datetime import datetime
from typing import Optional

from pydantic import BaseModel


class CategoryBase(BaseModel):
    name: str
    description: Optional[str] = None

class CategoryCreate(CategoryBase):
    pass

class CategoryUpdate(BaseModel):
    name: Optional[str] = None
    description: Optional[str] = None

class Category(CategoryBase):
    id: int
    created_at: datetime

    class Config:
        from_attributes = True

class SupplierBase(BaseModel):
    name: str
    contact_person: Optional[str] = None
    email: Optional[str] = None
    phone: Optional[str] = None
    address: Optional[str] = None

class SupplierCreate(SupplierBase):
    pass

class SupplierUpdate(BaseModel):
    name: Optional[str] = None
    contact_person: Optional[str] = None
    email: Optional[str] = None
    phone: Optional[str] = None
    address: Optional[str] = None

class Supplier(SupplierBase):
    id: int
    created_at: datetime

    class Config:
        from_attributes = True

class InventoryItemBase(BaseModel):
    name: str
    sku: str
    description: Optional[str] = None
    quantity: int = 0
    unit_price: float
    minimum_stock: int = 0
    category_id: Optional[int] = None
    supplier_id: Optional[int] = None

class InventoryItemCreate(InventoryItemBase):
    pass

class InventoryItemUpdate(BaseModel):
    name: Optional[str] = None
    description: Optional[str] = None
    quantity: Optional[int] = None
    unit_price: Optional[float] = None
    minimum_stock: Optional[int] = None
    category_id: Optional[int] = None
    supplier_id: Optional[int] = None

class InventoryItem(InventoryItemBase):
    id: int
    created_at: datetime
    updated_at: datetime
    category: Optional[Category] = None
    supplier: Optional[Supplier] = None

    class Config:
        from_attributes = True