from __future__ import annotations

from datetime import datetime
from typing import TYPE_CHECKING, List

from .enums import MiningOperationType, sql_enum
from .profitability_snapshot import ProjectProfitability

from sqlalchemy import DateTime, ForeignKey, 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
    from .pricing_settings import PricingSettings


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(
        sql_enum(MiningOperationType, name="miningoperationtype"),
        nullable=False,
        default=MiningOperationType.OTHER,
    )
    description: Mapped[str | None] = mapped_column(Text, nullable=True)
    pricing_settings_id: Mapped[int | None] = mapped_column(
        ForeignKey("pricing_settings.id", ondelete="SET NULL"),
        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,
    )
    pricing_settings: Mapped["PricingSettings | None"] = relationship(
        "PricingSettings",
        back_populates="projects",
    )
    profitability_snapshots: Mapped[List["ProjectProfitability"]] = relationship(
        "ProjectProfitability",
        back_populates="project",
        cascade="all, delete-orphan",
        order_by=lambda: ProjectProfitability.calculated_at.desc(),
        passive_deletes=True,
    )

    @property
    def latest_profitability(self) -> "ProjectProfitability | None":
        """Return the most recent profitability snapshot, if any."""

        if not self.profitability_snapshots:
            return None
        return self.profitability_snapshots[0]

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