// Invite-only registration.
//
// registration_enabled is a single on/off switch: open to anyone, or closed to
// everyone. This adds the middle setting an operator actually wants — open to
// people you invited. A code is single-use, expires, and can be revoked or
// deleted without touching the account it created.
//
// The code is stored hashed. An invite grants account creation, so a leaked
// settings dump or database backup should not hand someone a working code, the
// same reason password reset tokens are not stored in the clear.

exports.up = pgm => {
  pgm.sql(`
    CREATE TABLE IF NOT EXISTS registration_invites (
      id SERIAL PRIMARY KEY,
      code_hash TEXT NOT NULL UNIQUE,
      -- The last few characters, so the list can show which code a row is
      -- without being able to reconstruct it.
      code_hint TEXT NOT NULL,
      note TEXT NOT NULL DEFAULT '',
      created_by INTEGER REFERENCES users(id) ON DELETE SET NULL,
      created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
      expires_at TIMESTAMPTZ NOT NULL,
      -- Set when used. The row is kept so an admin can see who used which code.
      used_at TIMESTAMPTZ,
      used_by INTEGER REFERENCES users(id) ON DELETE SET NULL,
      -- Set when revoked. Separate from deletion: a revoked code stays visible.
      revoked_at TIMESTAMPTZ,
      revoked_by INTEGER REFERENCES users(id) ON DELETE SET NULL
    );
    CREATE INDEX IF NOT EXISTS idx_registration_invites_hash ON registration_invites(code_hash);
    CREATE INDEX IF NOT EXISTS idx_registration_invites_expires ON registration_invites(expires_at);
  `);
};

exports.down = pgm => {
  pgm.sql('DROP TABLE IF EXISTS registration_invites;');
};