# frozen_string_literal: true
##############################################################################
#                           Foreign Key Plugin
##############################################################################

RSpec.configure do |config|
  config.around(:each, :disable_foreign_keys => lambda { |v| !!v }) do |example|
    options = example.metadata[:disable_foreign_keys]
    options = case options
              when Array
                { :tables => options.map(&:to_s) }
              when String, Symbol
                { :tables => [options.to_s] }
              when FalseClass
                { :tables => [] }
              when TrueClass
                { :tables => :all }
              end

    foreign_key_names_sql = <<~HEREDOC
      SELECT
        "constraint_column_usage"."constraint_name",
        "pg_class"."relname"                          AS "local_table_name",
        "constraint_column_usage"."table_name"        AS "foreign_table_name",
        "constraint_column_usage"."column_name"       AS "foreign_column_name"
      FROM
        "information_schema"."constraint_column_usage"
        INNER JOIN
        "pg_constraint"
          ON
            "constraint_column_usage"."constraint_name" = "pg_constraint"."conname"
        INNER JOIN
        "pg_class"
          ON
            "pg_class"."oid" = "pg_constraint"."conrelid"
      WHERE
        "pg_constraint"."contype" = 'f'
        AND
        "pg_constraint"."condeferrable" = 't'
    HEREDOC

    unless options[:tables] == :all
      foreign_key_names_sql += 'AND ('

      table_constraint_sql = options[:tables].map do |table_name|
        %Q{"pg_class"."relname" = '#{table_name}'}
      end

      foreign_key_names_sql += table_constraint_sql.join(' OR ')

      foreign_key_names_sql += ')'
    end

    foreign_keys_to_disable = ActiveRecord::Base.connection.select_values(foreign_key_names_sql).join(',')
    ActiveRecord::Base.connection.execute('SET CONSTRAINTS %s DEFERRED' % foreign_keys_to_disable)

    example.run
  end
end