package deepequal

import (
	"reflect"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"go.skia.org/infra/go/sktest"
	"go.skia.org/infra/go/testutils"
	"go.skia.org/infra/go/testutils/unittest"
)

func TestTime(t *testing.T) {
	unittest.SmallTest(t)

	t1 := time.Now()
	t2 := t1.Round(0)

	AssertDeepEqual(t, t1, t2)
}

type customEqualValue struct {
	a string
}

func (b customEqualValue) Equal(o customEqualValue) bool {
	return b.a == "foo" && o.a == "bar"
}

func TestCustomEqualValue(t *testing.T) {
	unittest.SmallTest(t)

	a := customEqualValue{a: "foo"}
	b := customEqualValue{a: "bar"}

	AssertDeepEqual(t, a, b)
}

type customEqualPointer struct {
	a string
}

func (b *customEqualPointer) Equal(o customEqualPointer) bool {
	return true
}

func TestCustomEqualPointer(t *testing.T) {
	unittest.SmallTest(t)

	a := customEqualPointer{a: "foo"}
	b := customEqualPointer{a: "bar"}

	AssertDeepEqual(t, a, b)
}

type equalNoArgs struct {
	a string
}

func (b equalNoArgs) Equal() bool {
	return true
}

func TestEqualWithNoArgs(t *testing.T) {
	unittest.SmallTest(t)

	a := &equalNoArgs{a: "foo"}
	b := &equalNoArgs{a: "bar"}

	assert.False(t, DeepEqual(a, b))
}

type equalWrongArgs struct {
	a string
}

func (b equalWrongArgs) Equal(foo time.Time) bool {
	return true
}

func TestEqualWithWrongArgs(t *testing.T) {
	unittest.SmallTest(t)

	a := &equalWrongArgs{a: "foo"}
	b := &equalWrongArgs{a: "bar"}

	assert.False(t, DeepEqual(a, b))
}

type infiniteNesting struct {
	alpha interface{}
}

func TestInfiniteNesting(t *testing.T) {
	unittest.SmallTest(t)

	a := &infiniteNesting{}
	a.alpha = a
	b := &infiniteNesting{}
	b.alpha = b

	assert.True(t, reflect.DeepEqual(a, b))

	AssertDeepEqual(t, a, b)
}

func TestAssertJSONRoundTrip(t *testing.T) {
	unittest.SmallTest(t)

	type Success struct {
		Public int `json:"public"`
	}
	AssertJSONRoundTrip(t, &Success{
		Public: 123,
	})

	type Unencodable struct {
		Unsupported map[Success]struct{} `json:"unsupported"`
	}
	testutils.AssertFails(t, `unsupported type: map\[\w+\.Success]struct`, func(t sktest.TestingT) {
		AssertJSONRoundTrip(t, &Unencodable{
			Unsupported: map[Success]struct{}{
				{
					Public: 5,
				}: {},
			},
		})
	})

	type CantRoundTrip struct {
		// go vet complains if we add a json struct field tag to a private field.
		private int
	}
	testutils.AssertFails(t, "Objects do not match", func(t sktest.TestingT) {
		AssertJSONRoundTrip(t, &CantRoundTrip{
			private: 123,
		})
	})
}