"""Rename plan and per-operation journal persistence (US04-01, US04-02).

A plan is the complete, reviewable preview of a set of folder renames: every source,
destination, affected asset, expected hash, and validation issue. Nothing here
touches the filesystem — applying a plan is US04-03.

The journal columns on ``RenameOperation`` belong to US04-02's crash-safe state
machine and are created with the table so the journal never has to re-migrate the
rows the planner writes. They stay at their defaults until apply runs.
"""

from __future__ import annotations

from datetime import datetime

from sqlalchemy import (
    Boolean,
    DateTime,
    ForeignKey,
    Integer,
    String,
    UniqueConstraint,
    func,
)
from sqlalchemy.orm import Mapped, mapped_column

from photo_pipeline.db import Base


class RenamePlan(Base):
    __tablename__ = "rename_plans"

    id: Mapped[str] = mapped_column(String, primary_key=True)
    # planned | validated | invalid | applying | applied | failed | rolled_back
    state: Mapped[str] = mapped_column(String, nullable=False, default="planned")
    schema_version: Mapped[int] = mapped_column(Integer, nullable=False, default=1)
    checksum: Mapped[str | None] = mapped_column(String)
    blockers: Mapped[str | None] = mapped_column(String)  # JSON array
    operation_count: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    version: Mapped[int] = mapped_column(Integer, nullable=False, default=1)
    validated_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True))
    applied_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=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()
    )


class RenameOperation(Base):
    __tablename__ = "rename_operations"
    __table_args__ = (
        UniqueConstraint("plan_id", "sequence", name="uq_rename_operations_plan_sequence"),
    )

    id: Mapped[str] = mapped_column(String, primary_key=True)
    plan_id: Mapped[str] = mapped_column(
        ForeignKey("rename_plans.id", ondelete="CASCADE"), nullable=False, index=True
    )
    sequence: Mapped[int] = mapped_column(Integer, nullable=False)
    operation: Mapped[str] = mapped_column(String, nullable=False)
    album: Mapped[str | None] = mapped_column(String)
    source_path: Mapped[str] = mapped_column(String, nullable=False)
    destination_path: Mapped[str] = mapped_column(String, nullable=False)

    asset_ids: Mapped[str | None] = mapped_column(String)  # JSON array
    expected_sha256: Mapped[str | None] = mapped_column(String)  # JSON {asset_id: sha}
    asset_count: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    same_filesystem: Mapped[bool | None] = mapped_column(Boolean)
    case_only: Mapped[bool] = mapped_column(Boolean, nullable=False, default=False)
    issues: Mapped[str | None] = mapped_column(String)  # JSON array

    # ── journal (US04-02) ────────────────────────────────────────────────────
    journal_state: Mapped[str] = mapped_column(String, nullable=False, default="planned")
    attempt_count: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    fencing_token: Mapped[int | None] = mapped_column(Integer)
    worker_id: Mapped[str | None] = mapped_column(String)
    verified_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True))
    error_code: Mapped[str | None] = mapped_column(String)
    error_message: Mapped[str | None] = mapped_column(String)
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), nullable=False, server_default=func.now(), onupdate=func.now()
    )