package sets

import (
	"testing"

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

func getSetForElements(t *testing.T, elements ...int) *Set[int] {
	t.Helper()

	target := map[int]struct{}{}
	for _, el := range elements {
		target[el] = struct{}{}
	}

	return &Set[int]{
		store: target,
	}
}

func TestUnion(t *testing.T) {
	base := getSetForElements(t, 0, 1, 2, 3, 4, 5)
	other := getSetForElements(t, 3, 4, 5, 6, 7, 8)
	expected := []int{0, 1, 2, 3, 4, 5, 6, 7, 8}

	require.ElementsMatch(t, expected, Union(base, other).Slice())
}

func TestIntersection(t *testing.T) {
	base := getSetForElements(t, 0, 1, 2, 3, 4, 5)
	other := getSetForElements(t, 3, 4, 5, 6, 7, 8)
	expected := []int{3, 4, 5}

	require.ElementsMatch(t, expected, Intersection(base, other).Slice())
}

func TestDiff(t *testing.T) {
	base := getSetForElements(t, 0, 1, 2, 3, 4, 5)
	other := getSetForElements(t, 3, 4, 5, 6, 7, 8)
	expected := []int{0, 1, 2}

	require.ElementsMatch(t, expected, Diff(base, other).Slice())
}

func TestSymmetricDiff(t *testing.T) {
	base := getSetForElements(t, 0, 1, 2, 3, 4, 5)
	other := getSetForElements(t, 3, 4, 5, 6, 7, 8)
	expected := []int{0, 1, 2, 6, 7, 8}

	require.ElementsMatch(t, expected, SymmetricDiff(base, other).Slice())
}

func TestEqual(t *testing.T) {
	base := getSetForElements(t, 0, 1, 2, 3, 4, 5)
	otherDifferent := getSetForElements(t, 3, 4, 5, 6, 7, 8)
	otherEqual := getSetForElements(t, 0, 1, 2, 3, 4, 5)

	require.False(t, Equal(base, otherDifferent))
	require.True(t, Equal(base, otherEqual))
}