Gab Social. All are welcome.

app/models/invite.rb

@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+# == Schema Information
+#
+# Table name: invites
+#
+#  id         :bigint(8)        not null, primary key
+#  user_id    :bigint(8)        not null
+#  code       :string           default(""), not null
+#  expires_at :datetime
+#  max_uses   :integer
+#  uses       :integer          default(0), not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#  autofollow :boolean          default(FALSE), not null
+#
+
+class Invite < ApplicationRecord
+  include Expireable
+
+  belongs_to :user
+  has_many :users, inverse_of: :invite
+
+  scope :available, -> { where(expires_at: nil).or(where('expires_at >= ?', Time.now.utc)) }
+
+  before_validation :set_code
+
+  def valid_for_use?
+    (max_uses.nil? || uses < max_uses) && !expired?
+  end
+
+  private
+
+  def set_code
+    loop do
+      self.code = ([*('a'..'z'), *('A'..'Z'), *('0'..'9')] - %w(0 1 I l O)).sample(8).join
+      break if Invite.find_by(code: code).nil?
+    end
+  end
+end