package primes

import (
	"testing"

	"github.com/stretchr/testify/assert"
)

func TestWheelCantBeExpandedYet(t *testing.T) {
	s := newWheel6(primes)
	assert.Nil(t, s.expand())
}

func TestWheelIsExpanded(t *testing.T) {
	s6 := newWheel6(primes)
	s6.resetTo(419)
	assert.Equal(t, 0, s6.offset)

	s30 := s6.expand()
	assert.EqualValues(t, []int64{2, 6, 4, 2, 4, 2, 4, 6}, s30.elements)
	assert.EqualValues(t, []int64{2, 3, 5}, s30.primes)
	assert.Equal(t, int64(30), s30.size)
	assert.Equal(t, 0, s30.offset)
	assert.Equal(t, s6.n, s30.n)

	s210 := s30.expand()
	assert.EqualValues(t, []int64{2, 3, 5, 7}, s210.primes)
	assert.Equal(t, 48, len(s210.elements))
	assert.Equal(t, int64(210), s210.size)
	assert.Equal(t, 0, s210.offset)
	assert.Equal(t, s30.n, s210.n)
}