require 'cases/helper'
require 'support/connection_helper'

class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
  self.use_transactional_tests = false

  include ConnectionHelper

  IS_REFERENTIAL_INTEGRITY_SQL = lambda do |sql|
    sql.match(/DISABLE TRIGGER ALL/) || sql.match(/ENABLE TRIGGER ALL/)
  end

  module MissingSuperuserPrivileges
    def execute(sql)
      if IS_REFERENTIAL_INTEGRITY_SQL.call(sql)
        super "BROKEN;" rescue nil # put transaction in broken state
        raise ActiveRecord::StatementInvalid, 'PG::InsufficientPrivilege'
      else
        super
      end
    end
  end

  module ProgrammerMistake
    def execute(sql)
      if IS_REFERENTIAL_INTEGRITY_SQL.call(sql)
        raise ArgumentError, 'something is not right.'
      else
        super
      end
    end
  end

  def setup
    @connection = ActiveRecord::Base.connection
  end

  def teardown
    reset_connection
    if ActiveRecord::Base.connection.is_a?(MissingSuperuserPrivileges)
      raise "MissingSuperuserPrivileges patch was not removed"
    end
  end

  def test_should_reraise_invalid_foreign_key_exception_and_show_warning
    @connection.extend MissingSuperuserPrivileges

    warning = capture(:stderr) do
      e = assert_raises(ActiveRecord::InvalidForeignKey) do
        @connection.disable_referential_integrity do
          raise ActiveRecord::InvalidForeignKey, 'Should be re-raised'
        end
      end
      assert_equal 'Should be re-raised', e.message
    end
    assert_match (/WARNING: Rails was not able to disable referential integrity/), warning
    assert_match (/cause: PG::InsufficientPrivilege/), warning
  end

  def test_does_not_print_warning_if_no_invalid_foreign_key_exception_was_raised
    @connection.extend MissingSuperuserPrivileges

    warning = capture(:stderr) do
      e = assert_raises(ActiveRecord::StatementInvalid) do
        @connection.disable_referential_integrity do
          raise ActiveRecord::StatementInvalid, 'Should be re-raised'
        end
      end
      assert_equal 'Should be re-raised', e.message
    end
    assert warning.blank?, "expected no warnings but got:\n#{warning}"
  end

  def test_does_not_break_transactions
    @connection.extend MissingSuperuserPrivileges

    @connection.transaction do
      @connection.disable_referential_integrity do
        assert_transaction_is_not_broken
      end
      assert_transaction_is_not_broken
    end
  end

  def test_does_not_break_nested_transactions
    @connection.extend MissingSuperuserPrivileges

    @connection.transaction do
      @connection.transaction(requires_new: true) do
        @connection.disable_referential_integrity do
          assert_transaction_is_not_broken
        end
      end
      assert_transaction_is_not_broken
    end
  end

  def test_only_catch_active_record_errors_others_bubble_up
    @connection.extend ProgrammerMistake

    assert_raises ArgumentError do
      @connection.disable_referential_integrity {}
    end
  end

  private

  def assert_transaction_is_not_broken
    assert_equal 1, @connection.select_value("SELECT 1")
  end
end