import uuid
from datetime import datetime
from sqlalchemy import String, DateTime, Integer, Text, ForeignKey, func
from sqlalchemy.orm import Mapped, mapped_column
from app.database import Base


class Warehouse(Base):
    __tablename__ = "warehouses"
    id: Mapped[str] = mapped_column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    name: Mapped[str] = mapped_column(String(100))
    location: Mapped[str | None] = mapped_column(Text, nullable=True)
    manager_id: Mapped[str | None] = mapped_column(ForeignKey("employees.id"), nullable=True)
    is_active: Mapped[bool] = mapped_column(default=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, server_default=func.now())


class StockTransfer(Base):
    __tablename__ = "stock_transfers"
    id: Mapped[str] = mapped_column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    transfer_number: Mapped[str] = mapped_column(String(30), unique=True)
    from_warehouse: Mapped[str] = mapped_column(ForeignKey("warehouses.id"))
    to_warehouse: Mapped[str] = mapped_column(ForeignKey("warehouses.id"))
    item_id: Mapped[str] = mapped_column(ForeignKey("inventory.id"))
    quantity: Mapped[int] = mapped_column(Integer)
    status: Mapped[str] = mapped_column(String(20), default="pending")
    notes: Mapped[str | None] = mapped_column(Text, nullable=True)
    transferred_by: Mapped[str | None] = mapped_column(ForeignKey("users.id"), nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, server_default=func.now())