from __future__ import annotations

from datetime import datetime
from enum import Enum
from typing import TYPE_CHECKING, List

from sqlalchemy import DateTime, Enum as SQLEnum, Integer, String, Text
from sqlalchemy.orm import Mapped, mapped_column, relationship
from sqlalchemy.sql import func

from config.database import Base

if TYPE_CHECKING:  # pragma: no cover
    from .scenario import Scenario


class MiningOperationType(str, Enum):
    """Supported mining operation categories."""

    OPEN_PIT = "open_pit"
    UNDERGROUND = "underground"
    IN_SITU_LEACH = "in_situ_leach"
    PLACER = "placer"
    QUARRY = "quarry"
    MOUNTAINTOP_REMOVAL = "mountaintop_removal"
    OTHER = "other"


class Project(Base):
    """Top-level mining project grouping multiple scenarios."""

    __tablename__ = "projects"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, index=True)
    name: Mapped[str] = mapped_column(String(255), nullable=False, unique=True)
    location: Mapped[str | None] = mapped_column(String(255), nullable=True)
    operation_type: Mapped[MiningOperationType] = mapped_column(
        SQLEnum(MiningOperationType), nullable=False, default=MiningOperationType.OTHER
    )
    description: Mapped[str | None] = mapped_column(Text, nullable=True)
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), nullable=False, server_default=func.now()
    )
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), nullable=False, server_default=func.now(), onupdate=func.now()
    )

    scenarios: Mapped[List["Scenario"]] = relationship(
        "Scenario",
        back_populates="project",
        cascade="all, delete-orphan",
        passive_deletes=True,
    )

    def __repr__(self) -> str:  # pragma: no cover - helpful for debugging
        return f"Project(id={self.id!r}, name={self.name!r})"
