package iterator_test

import (
	"context"
	"reflect"
	"testing"

	. "github.com/cayleygraph/cayley/graph/iterator"
)

func TestSkipIteratorBasics(t *testing.T) {
	ctx := context.TODO()
	allIt := NewFixed(
		Int64Node(1),
		Int64Node(2),
		Int64Node(3),
		Int64Node(4),
		Int64Node(5),
	)

	u := NewSkip(allIt, 0)
	expectSz, _ := allIt.Size()
	if sz, _ := u.Size(); sz != expectSz {
		t.Errorf("Failed to check Skip size: got:%v expected:%v", sz, expectSz)
	}
	expect := []int{1, 2, 3, 4, 5}
	if got := iterated(u); !reflect.DeepEqual(got, expect) {
		t.Errorf("Failed to iterate Skip correctly: got:%v expected:%v", got, expect)
	}

	allIt.Reset()

	u = NewSkip(allIt, 3)
	expectSz = 2
	if sz, _ := u.Size(); sz != expectSz {
		t.Errorf("Failed to check Skip size: got:%v expected:%v", sz, expectSz)
	}
	expect = []int{4, 5}
	if got := iterated(u); !reflect.DeepEqual(got, expect) {
		t.Errorf("Failed to iterate Skip correctly: got:%v expected:%v", got, expect)
	}

	for _, v := range []int{1, 2, 3, 4, 5} {
		if !u.Contains(ctx, Int64Node(v)) {
			t.Errorf("Failed to find a correct value in the Skip iterator.")
		}
	}
}