"""The durable EXIF projection per asset and stage (concept §3, US07-03).

One row per ``(asset_id, stage)``: what the stage wanted written, what the file
looked like afterwards, and whether anything outside the stage's ownership moved.
``state = divergent`` is the whole point of the table — it survives restarts, keeps
the asset out of stages that require verified metadata, and gives a human something
to look at instead of a silent repair.
"""

from __future__ import annotations

from datetime import datetime

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

from photo_pipeline.db import Base


class ExifProjection(Base):
    __tablename__ = "exif_projections"

    asset_id: Mapped[str] = mapped_column(ForeignKey("assets.id"), primary_key=True)
    stage: Mapped[str] = mapped_column(String, primary_key=True)  # safety | analysis
    id: Mapped[str] = mapped_column(String, nullable=False)
    projection_version: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    desired_json: Mapped[str | None] = mapped_column(String)
    divergent_fields: Mapped[str | None] = mapped_column(String)  # JSON array
    result_file_sha256: Mapped[str | None] = mapped_column(String)
    state: Mapped[str] = mapped_column(String, nullable=False)  # verified|divergent|failed
    error_code: Mapped[str | None] = mapped_column(String)
    verified_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True))
    updated_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True))