"""EquipmentGroup (Bundle) model for grouping equipment items."""

import uuid
from datetime import datetime

from sqlalchemy import String, DateTime, ForeignKey, func, Float, Text, Table, Column
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.db.base import Base

# Many-to-many association table: equipment_groups ↔ equipment
equipment_group_items = Table(
    "equipment_group_items",
    Base.metadata,
    Column(
        "group_id",
        String(36),
        ForeignKey("equipment_groups.id", ondelete="CASCADE"),
        primary_key=True,
    ),
    Column(
        "equipment_id",
        String(36),
        ForeignKey("equipment.id", ondelete="CASCADE"),
        primary_key=True,
    ),
    Column(
        "quantity",
        Float,
        nullable=False,
        default=1.0,
    ),
)


class EquipmentGroup(Base):
    """Represents a bundle/group of equipment items."""

    __tablename__ = "equipment_groups"

    id: Mapped[str] = mapped_column(
        String(36), primary_key=True, default=lambda: str(uuid.uuid4())
    )
    account_id: Mapped[str] = mapped_column(
        String(36), ForeignKey("accounts.id", ondelete="CASCADE"), nullable=False
    )
    name: Mapped[str] = mapped_column(String(255), nullable=False)
    description: Mapped[str | None] = mapped_column(Text, nullable=True)
    daily_rate: Mapped[float | None] = mapped_column(Float, nullable=True)
    default_location_id: Mapped[str | None] = mapped_column(
        String(36), ForeignKey("stock_locations.id", ondelete="SET NULL"), nullable=True
    )

    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), server_default=func.now(), nullable=False
    )
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        server_default=func.now(),
        onupdate=func.now(),
        nullable=False,
    )

    # Relationships
    account: Mapped["Account"] = relationship(
        "Account", back_populates="equipment_groups"
    )
    default_location: Mapped["StockLocation"] = relationship(
        "StockLocation", back_populates="equipment_groups"
    )
    items: Mapped[list["Equipment"]] = relationship(
        "Equipment", secondary=equipment_group_items, backref="groups"
    )

    def __repr__(self) -> str:
        return f"<EquipmentGroup {self.name}>"