exports.up = (pgm) => {
  pgm.sql(`
    CREATE TABLE IF NOT EXISTS upload_links (
      id SERIAL PRIMARY KEY,
      label TEXT NOT NULL,
      -- The token itself is never stored, only its digest. A leaked database
      -- is then not also a leaked set of working upload links, and the admin
      -- screen can show a token exactly once — at creation — for the same
      -- reason a password reset link is not re-readable.
      token_hash TEXT NOT NULL UNIQUE,
      revoked_at TIMESTAMPTZ,
      submission_count INTEGER NOT NULL DEFAULT 0,
      -- Null means no cap. A link handed to a regular contributor is
      -- open-ended; one handed out for a single box of stock is not. The
      -- route defaults this to a finite number rather than null, so an
      -- unbounded link is something asked for rather than something that
      -- happens when nobody thought about it.
      max_submissions INTEGER,
      last_used_at TIMESTAMPTZ,
      created_at TIMESTAMPTZ NOT NULL DEFAULT now()
    );

    CREATE TABLE IF NOT EXISTS item_drafts (
      id SERIAL PRIMARY KEY,
      item_id INTEGER NOT NULL UNIQUE REFERENCES items(id) ON DELETE CASCADE,
      -- SET NULL rather than CASCADE: deleting a link must not delete the
      -- items that arrived through it. Provenance is lost; the goods are not.
      upload_link_id INTEGER REFERENCES upload_links(id) ON DELETE SET NULL,
      submitter_note TEXT,
      state TEXT NOT NULL DEFAULT 'queued',
      attempts INTEGER NOT NULL DEFAULT 0,
      model TEXT,
      ai_name TEXT,
      ai_description TEXT,
      ai_category_id INTEGER REFERENCES categories(id) ON DELETE SET NULL,
      ai_tag_names TEXT[],
      -- Kept even though a suggestion is also copied onto the item, so what
      -- the model proposed stays readable after the admin has edited the
      -- item's price. Without it there is no way to ask later whether the
      -- model's numbers were any good.
      ai_suggested_price_cents INTEGER,
      -- ai | default | admin. Where the item's current price came from.
      -- Recorded rather than inferred: a model that happens to suggest exactly
      -- 8000, or an admin who deliberately types the model's number, both
      -- collapse any comparison-based guess.
      price_source TEXT NOT NULL DEFAULT 'default',
      ai_error TEXT,
      input_tokens INTEGER,
      output_tokens INTEGER,
      cost_micros INTEGER,
      drafted_at TIMESTAMPTZ,
      reviewed_at TIMESTAMPTZ,
      created_at TIMESTAMPTZ NOT NULL DEFAULT now()
    );

    -- The review queue reads by state; everything else reads by item, which
    -- the UNIQUE constraint on item_id already indexes.
    CREATE INDEX IF NOT EXISTS item_drafts_state_idx ON item_drafts (state);

    -- A submitted item is priced on arrival rather than left unpriced, so the
    -- column keeps NOT NULL and only gains a fallback. 80.00 applies when
    -- nothing else supplies a price; the drafting worker in #223 writes a
    -- model's suggestion over it when there is one.
    --
    -- The number lives here rather than in configuration deliberately.
    -- Changing a default price is a rare, deliberate act that deserves a
    -- record; an environment variable would let it drift silently between
    -- environments, and a wrong default is invisible until something has
    -- already sold at it.
    ALTER TABLE items ALTER COLUMN price_cents SET DEFAULT 8000;
  `);
};

exports.down = (pgm) => {
  pgm.sql(`
    ALTER TABLE items ALTER COLUMN price_cents DROP DEFAULT;
    DROP TABLE IF EXISTS item_drafts;
    DROP TABLE IF EXISTS upload_links;
  `);
};