/*
Copyright 2019 The Kubernetes Authors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package printers

import (
	"bytes"
	"reflect"
	"testing"

	"github.com/google/go-cmp/cmp"
	v1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/util/json"
	"k8s.io/client-go/kubernetes/scheme"
)

var testData = TestStruct{
	TypeMeta:   metav1.TypeMeta{APIVersion: "foo/bar", Kind: "TestStruct"},
	Key:        "testValue",
	Map:        map[string]int{"TestSubkey": 1},
	StringList: []string{"a", "b", "c"},
	IntList:    []int{1, 2, 3},
}

type TestStruct struct {
	metav1.TypeMeta   `json:",inline"`
	metav1.ObjectMeta `json:"metadata,omitempty"`
	Key               string         `json:"Key"`
	Map               map[string]int `json:"Map"`
	StringList        []string       `json:"StringList"`
	IntList           []int          `json:"IntList"`
}

func (in *TestStruct) DeepCopyObject() runtime.Object {
	panic("never called")
}

func TestJSONPrinter(t *testing.T) {
	testPrinter(t, NewTypeSetter(scheme.Scheme).ToPrinter(&JSONPrinter{}), json.Unmarshal)
}

func testPrinter(t *testing.T, printer ResourcePrinter, unmarshalFunc func(data []byte, v interface{}) error) {
	buf := bytes.NewBuffer([]byte{})

	err := printer.PrintObj(&testData, buf)
	if err != nil {
		t.Fatal(err)
	}
	var poutput TestStruct
	// Verify that given function runs without error.
	err = unmarshalFunc(buf.Bytes(), &poutput)
	if err != nil {
		t.Fatal(err)
	}
	// Use real decode function to undo the versioning process.
	poutput = TestStruct{}
	s := scheme.Codecs.UniversalDecoder(scheme.Scheme.PrioritizedVersionsAllGroups()...)
	if err := runtime.DecodeInto(s, buf.Bytes(), &poutput); err != nil {
		t.Fatal(err)
	}
	if !reflect.DeepEqual(testData, poutput) {
		t.Errorf("Test data and unmarshaled data are not equal: %v", cmp.Diff(poutput, testData))
	}

	obj := &v1.Pod{
		TypeMeta:   metav1.TypeMeta{APIVersion: "v1", Kind: "Pod"},
		ObjectMeta: metav1.ObjectMeta{Name: "foo"},
	}
	// our decoder defaults, so we should default our expected object as well
	scheme.Scheme.Default(obj)
	buf.Reset()
	printer.PrintObj(obj, buf)
	var objOut v1.Pod
	// Verify that given function runs without error.
	err = unmarshalFunc(buf.Bytes(), &objOut)
	if err != nil {
		t.Fatalf("unexpected error: %#v", err)
	}
	// Use real decode function to undo the versioning process.
	objOut = v1.Pod{}
	if err := runtime.DecodeInto(s, buf.Bytes(), &objOut); err != nil {
		t.Fatal(err)
	}
	if !reflect.DeepEqual(obj, &objOut) {
		t.Errorf("Unexpected inequality:\n%v", cmp.Diff(obj, &objOut))
	}
}

func TestPrintersSuccess(t *testing.T) {
	om := func(name string) metav1.ObjectMeta { return metav1.ObjectMeta{Name: name} }

	genericPrinters := map[string]ResourcePrinter{
		"json": NewTypeSetter(scheme.Scheme).ToPrinter(&JSONPrinter{}),
		"yaml": NewTypeSetter(scheme.Scheme).ToPrinter(&YAMLPrinter{}),
	}
	objects := map[string]runtime.Object{
		"pod":             &v1.Pod{ObjectMeta: om("pod")},
		"emptyPodList":    &v1.PodList{},
		"nonEmptyPodList": &v1.PodList{Items: []v1.Pod{{}}},
		"endpoints": &v1.Endpoints{
			Subsets: []v1.EndpointSubset{{
				Addresses: []v1.EndpointAddress{{IP: "127.0.0.1"}, {IP: "localhost"}},
				Ports:     []v1.EndpointPort{{Port: 8080}},
			}}},
	}

	// Test PrintObj() success.
	for pName, p := range genericPrinters {
		for oName, obj := range objects {
			b := &bytes.Buffer{}
			if err := p.PrintObj(obj, b); err != nil {
				t.Errorf("printer '%v', object '%v'; error: '%v'", pName, oName, err)
			}
		}
	}
}