database_connection.rb

# frozen_string_literal: true

module DatabaseConnection
  class << self
    def db_name
      ENV.fetch("DB", "mysql2")
    end

    def setup
      db_config = DEFAULT_CONFIG.fetch(db_name)
      begin
        ActiveRecord::Base.establish_connection(db_config)
        ActiveRecord::Base.connection
      rescue
        raise unless db_config.is_a?(Hash)

        ActiveRecord::Base.establish_connection(db_config.merge("database" => nil))
        ActiveRecord::Base.connection.create_database(db_config["database"])
        ActiveRecord::Base.establish_connection(db_config)
      end
    end

    def drop_tables
      TABLES.keys.each do |table|
        ActiveRecord::Base.connection.drop_table(table) if table_exists?(table)
      end
    end

    def table_exists?(table)
      if ActiveRecord::Base.connection.respond_to?(:data_source_exists?)
        ActiveRecord::Base.connection.data_source_exists?(table)
      else
        ActiveRecord::Base.connection.table_exists?(table)
      end
    end

    def create_tables
      TABLES.each do |table, fields|
        fields = fields.dup
        options = fields.last.is_a?(Hash) ? fields.pop : {}
        ActiveRecord::Base.connection.create_table(table, **options) do |t|
          fields.each do |column_type, *args|
            if args.last.is_a?(Hash)
              kwargs = args.pop
              t.send(column_type, *args, **kwargs)
            else
              t.send(column_type, *args)
            end
          end
        end
      end
    end
  end

  TABLES = {
    polymorphic_records: [[:string, :owner_type], [:integer, :owner_id], [:timestamps, null: true]],
    deeply_associated_records: [
      [:string, :name], [:integer, :associated_record_id], [:integer, :item_id], [:timestamps, null: true],
    ],
    associated_records: [[:string, :name], [:integer, :item_id], [:integer, :item_two_id], [:timestamps, null: true]],
    normalized_associated_records: [[:string, :name], [:integer, :item_id], [:timestamps, null: true]],
    no_inverse_of_records: [[:integer, :owner_id], [:timestamps, null: true]],
    not_cached_records: [[:string, :name], [:integer, :item_id], [:timestamps, null: true]],
    items: [[:integer, :item_id], [:string, :title], [:timestamps, null: true]],
    items2: [[:integer, :item_id], [:string, :title], [:timestamps, null: true]],
    related_items: [[:integer, :owner_id], [:string, :owner_type], [:integer, :item_id], [:timestamps, null: true]],
    keyed_records: [[:string, :value], primary_key: "hashed_key"],
    sti_records: [[:string, :type], [:string, :name]],
    custom_parent_records: [[:integer, :parent_primary_key], id: false, primary_key: "parent_primary_key"],
    custom_child_records: [
      [:integer, :child_primary_key], [:integer, :parent_id], id: false, primary_key: "child_primary_key",
    ],
  }

  DEFAULT_CONFIG = {
    "mysql2" => {
      "adapter" => "mysql2",
      "database" => "identity_cache_test",
      "host" => ENV["MYSQL_HOST"] || "127.0.0.1",
      "username" => "root",
      "port" => ENV["MYSQL_PORT"] ? Integer(ENV["MYSQL_PORT"]) : 3306,
      "password" => ENV["MYSQL_PASSWORD"] || "my-secret-pw",
    },
    "postgresql" => {
      "adapter" => "postgresql",
      "database" => "identity_cache_test",
      "host" => ENV["POSTGRES_HOST"] || "127.0.0.1",
      "username" => "postgres",
      "password" => ENV["POSTGRES_PASSWORD"],
      "prepared_statements" => false,
    },
  }
end