from datetime import datetime

from sqlalchemy import JSON, DateTime, ForeignKey, Integer, String, UniqueConstraint
from sqlalchemy.orm import Mapped, mapped_column

from app.core.constants import ActorValue
from app.core.database import Base
from app.core.utils.time import utc_now
from app.modules.workflows.constants import WorkflowStatus


class WorkflowInstance(Base):
    __tablename__ = "workflow_instances"
    __table_args__ = (
        UniqueConstraint(
            "workflow_type",
            "aggregate_type",
            "aggregate_id",
            name="uq_workflow_aggregate",
        ),
    )

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    code: Mapped[str] = mapped_column(String(64), unique=True, index=True)
    workflow_type: Mapped[str] = mapped_column(String(128), index=True)
    aggregate_type: Mapped[str] = mapped_column(String(128), index=True)
    aggregate_id: Mapped[str | None] = mapped_column(String(128), nullable=True, index=True)
    status: Mapped[str] = mapped_column(String(32), default=WorkflowStatus.RUNNING, index=True)
    actor: Mapped[str] = mapped_column(String(128), default=ActorValue.SYSTEM, index=True)
    current_step: Mapped[str | None] = mapped_column(String(128), nullable=True)
    payload: Mapped[dict | None] = mapped_column(JSON, nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=utc_now, index=True)
    updated_at: Mapped[datetime] = mapped_column(
        DateTime,
        default=utc_now,
        onupdate=utc_now,
    )
    completed_at: Mapped[datetime | None] = mapped_column(DateTime, nullable=True, index=True)


class WorkflowAction(Base):
    __tablename__ = "workflow_actions"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    code: Mapped[str] = mapped_column(String(64), unique=True, index=True)
    workflow_code: Mapped[str] = mapped_column(
        ForeignKey("workflow_instances.code", ondelete="RESTRICT"),
        index=True,
    )
    action: Mapped[str] = mapped_column(String(128), index=True)
    actor: Mapped[str] = mapped_column(String(128), default=ActorValue.SYSTEM, index=True)
    from_status: Mapped[str | None] = mapped_column(String(32), nullable=True)
    to_status: Mapped[str | None] = mapped_column(String(32), nullable=True)
    payload: Mapped[dict | None] = mapped_column(JSON, nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=utc_now, index=True)