-- channel_errors: channels that returned HTTP 404 (deleted/private) on the most
-- recent scheduler pass. Surfaced on the account page so users know why some
-- subscribed channels produce no videos. Upserted per-pass; cleared when the
-- channel starts returning results again (runner calls UpsertChannelError only
-- on 404, so a recovered channel simply stops appearing after its row ages out
-- or the user takes action). ON DELETE CASCADE keeps rows tidy on account deletion.
CREATE TABLE channel_errors (
    user_id      UUID        NOT NULL REFERENCES users(id)  ON DELETE CASCADE,
    channel_id   TEXT        NOT NULL,
    channel_name TEXT        NOT NULL,
    first_seen   TIMESTAMPTZ NOT NULL DEFAULT now(),
    last_seen    TIMESTAMPTZ NOT NULL DEFAULT now(),
    PRIMARY KEY (user_id, channel_id)
);

CREATE INDEX idx_channel_errors_user_id ON channel_errors(user_id);

ALTER TABLE channel_errors ENABLE ROW LEVEL SECURITY;
ALTER TABLE channel_errors FORCE ROW LEVEL SECURITY;
CREATE POLICY channel_errors_isolation ON channel_errors
    FOR ALL
    USING (user_id = current_setting('tapir.current_user_id', true)::uuid);