package list

import (
	"github.com/stretchr/testify/assert"
	"pgregory.net/rapid"
	"testing"
)

// func TestListLen(t *testing.T) {
// 	assert.Equal(t, 0, Empty().Len(), "should insert at head")
// 	assert.Equal(t, 1, Empty().Conj(1).Len(), "should insert at head")
// 	assert.Equal(t, 2, Empty().Conj(1).Conj(2).Len(), "should insert at head")
// }
//
// func TestListString(t *testing.T) {
// 	assert.Equal(t, "()", Empty().String(), "should insert at head")
// }
//
// func TestListConj(t *testing.T) {
// 	var l IList
// 	assert.Equal(t, "()", Empty().String(), "should insert at head")
// 	l = New(5)
// 	assert.Equal(t, "(5)", l.String(), "should insert at head")
// 	l = Empty().Conj(4)
// 	assert.Equal(t, "(4)", l.String(), "should insert at head")
// }
//
// func TestListFirst(t *testing.T) {
// 	l := Empty().Conj(5).Conj(6).Conj(7)
// 	assert.Equal(t, 7, l.First(), "should return first element")
// 	assert.Equal(t, nil, Empty().First(), "should return nil")
// }
//
// func TestListRest(t *testing.T) {
// 	l := Empty().Conj(5).Conj(6).Conj(7)
// 	assert.Equal(t, "(6 5)", l.Rest().String(), "should return rest sublist")
// 	assert.Equal(t, "(5)", l.Rest().Rest().String(), "should return rest sublist")
// 	assert.Equal(t, "()", l.Rest().Rest().Rest().String(), "should return rest sublist")
// 	assert.Equal(t, Empty(), Empty().Rest(), "should return rest sublist")
// 	assert.Equal(t, Empty(), Empty().Rest().Rest(), "should return rest sublist")
// }

// generative tests
func ListLengthProperty(t *testing.T) {
	myList := Empty()
	expectedSized := 0
	rapid.Check(t, func(t *rapid.T) {
		t.Repeat(map[string]func(*rapid.T){
			"conj": func(t *rapid.T) {
				expectedSized += 1
				myList = myList.Conj(rapid.Int().Draw(t, "el"))
			},
			"rest": func(t *rapid.T) {
				if !myList.IsEmpty() {
					expectedSized -= 1
				}
				myList = myList.Rest()
			},
			"stringify": func(t *rapid.T) {
				myList.String()
			},

			"": func(t *rapid.T) {
				assert.Equal(t, myList.Len(), expectedSized, "must be equal")
			},
		})
	})
}