import uuid
from datetime import datetime
from typing import Optional, Any
from sqlalchemy import String, DateTime, ForeignKey, Boolean
from sqlalchemy.orm import Mapped, mapped_column, relationship
from sqlalchemy.dialects.postgresql import UUID, JSONB
from app.core.database import Base


class Session(Base):
    __tablename__ = "sessions"

    id: Mapped[uuid.UUID] = mapped_column(
        UUID(as_uuid=True),
        primary_key=True,
        default=uuid.uuid4
    )
    tree_id: Mapped[uuid.UUID] = mapped_column(
        UUID(as_uuid=True),
        ForeignKey("trees.id"),
        nullable=False,
        index=True
    )
    user_id: Mapped[uuid.UUID] = mapped_column(
        UUID(as_uuid=True),
        ForeignKey("users.id"),
        nullable=False,
        index=True
    )
    tree_snapshot: Mapped[dict[str, Any]] = mapped_column(JSONB, nullable=False)
    path_taken: Mapped[list[str]] = mapped_column(JSONB, nullable=False, default=list)
    decisions: Mapped[list[dict[str, Any]]] = mapped_column(JSONB, nullable=False, default=list)
    started_at: Mapped[datetime] = mapped_column(
        DateTime,
        default=datetime.utcnow,
        index=True
    )
    completed_at: Mapped[Optional[datetime]] = mapped_column(DateTime, nullable=True, index=True)
    ticket_number: Mapped[Optional[str]] = mapped_column(String(100), nullable=True)
    client_name: Mapped[Optional[str]] = mapped_column(String(255), nullable=True)
    exported: Mapped[bool] = mapped_column(Boolean, default=False)

    # Relationships
    tree: Mapped["Tree"] = relationship("Tree", back_populates="sessions")
    user: Mapped["User"] = relationship("User", back_populates="sessions")
    attachments: Mapped[list["Attachment"]] = relationship("Attachment", back_populates="session")