-- Non-destructive photo editing: the parameters live in the photo metadata and
-- the edited image is stored as separate objects next to the base variants.
-- SQLite cannot alter a CHECK constraint, so photo_objects is rebuilt with the
-- extended role set.

ALTER TABLE photos ADD COLUMN edit_params TEXT NOT NULL DEFAULT '{}';

CREATE TABLE photo_objects_new (
    photo_id  TEXT NOT NULL REFERENCES photos(id) ON DELETE CASCADE,
    object_id TEXT NOT NULL REFERENCES objects(id) ON DELETE RESTRICT,
    role      TEXT NOT NULL CHECK (role IN ('original', 'thumb', 'medium', 'preview', 'playback',
                                            'edit', 'edit_thumb', 'edit_medium', 'edit_preview')),
    PRIMARY KEY (photo_id, role)
);

INSERT INTO photo_objects_new (photo_id, object_id, role)
SELECT photo_id, object_id, role FROM photo_objects;

DROP TABLE photo_objects;

ALTER TABLE photo_objects_new RENAME TO photo_objects;

CREATE INDEX IF NOT EXISTS photo_objects_object_idx ON photo_objects (object_id);

-- Durable queue of pending edit renders, one job per photo.
CREATE TABLE edit_jobs (
    photo_id        TEXT PRIMARY KEY REFERENCES photos(id) ON DELETE CASCADE,
    attempts        INTEGER NOT NULL DEFAULT 0,
    next_attempt_at TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now')),
    last_error      TEXT NOT NULL DEFAULT '',
    created_at      TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
);

CREATE INDEX edit_jobs_due_idx ON edit_jobs (next_attempt_at);