"""Deal model: sales opportunities tied to an account."""

from __future__ import annotations

from datetime import date
from decimal import Decimal
from enum import Enum
from typing import TYPE_CHECKING

from sqlalchemy import Date, ForeignKey, Numeric, String
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.models.base import Base, OrgScopedMixin, SoftDeleteMixin, TimestampMixin

if TYPE_CHECKING:
    from app.models.account import Account
    from app.models.activity import Activity
    from app.models.deal_stage_history import DealStageHistory
    from app.models.note import Note
    from app.models.tag_link import TagLink
    from app.models.user import User


class DealStage(str, Enum):
    """Sales pipeline stage for a deal."""

    lead = "lead"
    qualified = "qualified"
    proposal = "proposal"
    negotiation = "negotiation"
    won = "won"
    lost = "lost"


class Deal(Base, TimestampMixin, SoftDeleteMixin, OrgScopedMixin):
    __tablename__ = "deals"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    title: Mapped[str] = mapped_column(String(255), nullable=False)
    value: Mapped[Decimal] = mapped_column(Numeric(12, 2), nullable=False, default=Decimal("0"))
    currency: Mapped[str] = mapped_column(
        String(3), nullable=False, default="EUR", server_default="EUR"
    )
    stage: Mapped[DealStage] = mapped_column(
        String(32),
        nullable=False,
        default=DealStage.lead,
        server_default=DealStage.lead.value,
        index=True,
    )
    close_date: Mapped[date | None] = mapped_column(Date, nullable=True)
    account_id: Mapped[int] = mapped_column(ForeignKey("accounts.id"), nullable=False, index=True)
    owner_id: Mapped[int] = mapped_column(ForeignKey("users.id"), nullable=False, index=True)
    won_lost_reason: Mapped[str | None] = mapped_column(String(512), nullable=True)

    # Relationships
    account: Mapped[Account] = relationship("Account", back_populates="deals", lazy="selectin")
    owner: Mapped[User] = relationship("User", foreign_keys=[owner_id], lazy="joined")
    stage_history: Mapped[list[DealStageHistory]] = relationship(
        "DealStageHistory",
        back_populates="deal",
        cascade="all, delete-orphan",
        lazy="selectin",
        order_by="DealStageHistory.created_at",
    )
    activities: Mapped[list[Activity]] = relationship(
        "Activity", back_populates="deal", lazy="selectin"
    )
    notes: Mapped[list[Note]] = relationship(
        "Note",
        primaryjoin="and_(Deal.id==foreign(Note.parent_id), Note.parent_type=='deal')",
        viewonly=True,
        lazy="selectin",
    )
    tags: Mapped[list[TagLink]] = relationship(
        "TagLink",
        primaryjoin="and_(Deal.id==foreign(TagLink.parent_id), TagLink.parent_type=='deal')",
        viewonly=True,
        lazy="selectin",
    )

    def __repr__(self) -> str:
        return f"<Deal id={self.id} title={self.title!r} stage={self.stage}>"


__all__ = ["Deal", "DealStage"]