require_relative 'helper'

describe 'Adapter' do
  supported_by Swift::DB::Postgres do
    %w(America/Chicago Australia/Melbourne).each do |timezone|
      describe 'time parsing in %s' % timezone do
        before do
          ENV['TZ'] = ":#{timezone}"
          @db = Swift.db
          @db.execute 'create table datetime_test(id serial, ts timestamp with time zone)'
          @db.execute "set time zone '#{timezone}'"
        end

        after do
          @db.execute 'drop table datetime_test'
        end

        it 'should parse timestamps and do conversion accordingly' do
          time  = DateTime.parse('2010-01-01 15:00:00+04:30')
          assert_timestamp_like time, fetch_timestamp_at(time), 'parses correctly'
        end

        it 'should parse correctly when DST is on' do
          time  = DateTime.parse('2010-10-02 20:31:00+04:30')
          assert_timestamp_like time, fetch_timestamp_at(time), 'DST on'
        end

        it 'should parse correctly when DST is off' do
          time  = DateTime.parse('2010-04-04 20:31:00+04:30')
          assert_timestamp_like time, fetch_timestamp_at(time), 'DST off'
        end

        it 'should store fractional seconds' do
          time     = Time.now
          datetime = time.to_datetime

          @db.execute 'insert into datetime_test(ts) values (?), (?)', time, datetime
          values = @db.execute('select ts from datetime_test').map(&:values).flatten

          assert_equal 2, values.size

          # postgres resolution is microsecond.
          values.each do |value|
            assert_equal datetime.strftime('%F %T %z'), value.strftime('%F %T %z')
            assert_equal datetime.second_fraction.to_f.round(6), value.second_fraction.to_f.round(6)
          end
        end

        def fetch_timestamp_at value, zone='%z'
          sql = if zone.empty?
            "select '%s'::timestamp as now"
          else
            "select '%s'::timestamp with time zone as now"
          end

          sql = sql % value.strftime('%F %T' + zone)
          @db.execute(sql).first.fetch(:now)
        end

        def assert_timestamp_like expect, given, comment
          match = Regexp.new expect.to_time.strftime('%F %T')
          assert_kind_of DateTime, given
          assert_match match, given.to_time.strftime('%F %T'), comment
        end
      end
    end
  end
end