-- 0100_backup_music.up.sql — the music files in Minstrel's own backup.
--
-- Until now a backup held the database only. With include_music on, each
-- library file is also sent once to music/<path> in the same destination,
-- and sent again only when it changes.
--
--   backup_settings.include_music  off until an admin switches it on.
--   backup_music_files             one row per track sent (or refused): the
--                                  file's size and mtime when it was sent, so
--                                  a later night sends only what is new or
--                                  changed. A track the scan has touched since
--                                  checked_at is looked at again; it goes up
--                                  again only if the file itself changed, so a
--                                  full rescan doesn't resend the library. A
--                                  refusal is kept with its reason and tried
--                                  again once the file changes.
--   backup_runs.music_*            how much a run sent, and why it stopped.
ALTER TABLE backup_settings ADD COLUMN include_music boolean NOT NULL DEFAULT false;

ALTER TABLE backup_runs
    ADD COLUMN music_files integer NOT NULL DEFAULT 0,
    ADD COLUMN music_bytes bigint NOT NULL DEFAULT 0,
    ADD COLUMN music_note  text NOT NULL DEFAULT '';

CREATE TABLE backup_music_files (
    track_id uuid PRIMARY KEY REFERENCES tracks (id) ON DELETE CASCADE,
    -- The file as it was sent.
    size       bigint NOT NULL,
    mtime      timestamptz NOT NULL,
    -- Where it went: the object key, or the file's path in the folder.
    location   text NOT NULL,
    -- When the file was last sent or found unchanged.
    checked_at timestamptz NOT NULL DEFAULT now(),
    -- Empty when it was sent; otherwise why the destination refused it.
    error    text NOT NULL DEFAULT ''
);