/*
Copyright 2019 The KubeSphere 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 cache

import (
	"testing"
	"time"

	"github.com/google/go-cmp/cmp"
	"k8s.io/apimachinery/pkg/util/sets"
)

var dataSet = map[string]string{
	"foo1": "val1",
	"foo2": "val2",
	"foo3": "val3",
	"bar1": "val1",
	"bar2": "val2",
}

// load dataset into cache
func load(client Interface, data map[string]string) error {
	for k, v := range data {
		err := client.Set(k, v, NeverExpire)
		if err != nil {
			return err
		}
	}

	return nil
}

// dump retrieve all data in simple into a map
func dump(client Interface) (map[string]string, error) {
	keys, err := client.Keys("*")
	if err != nil {
		return nil, err
	}

	snapshot := make(map[string]string)
	for _, key := range keys {
		val, err := client.Get(key)
		if err != nil {
			continue
		}
		snapshot[key] = val
	}

	return snapshot, nil
}

func TestDeleteAndExpireCache(t *testing.T) {
	var testCases = []struct {
		description    string
		deleteKeys     sets.String
		expireKeys     sets.String
		expireDuration time.Duration // never use a 0(NeverExpires) duration with expireKeys, recommend time.Millisecond * 500.
		expected       map[string]string
	}{
		{
			description: "Should get all keys",
			expected: map[string]string{
				"foo1": "val1",
				"foo2": "val2",
				"foo3": "val3",
				"bar1": "val1",
				"bar2": "val2",
			},
		},
		{
			description: "Test delete should get only keys start with foo",
			expected: map[string]string{
				"foo1": "val1",
				"foo2": "val2",
				"foo3": "val3",
			},
			deleteKeys: sets.NewString("bar1", "bar2"),
		},
		{
			description: "Should get only keys start with bar",
			expected: map[string]string{
				"bar1": "val1",
				"bar2": "val2",
			},
			expireDuration: time.Millisecond * 500,
			expireKeys:     sets.NewString("foo1", "foo2", "foo3"),
		},
	}

	for _, testCase := range testCases {
		cacheClient := NewSimpleCache()

		t.Run(testCase.description, func(t *testing.T) {
			err := load(cacheClient, dataSet)
			if err != nil {
				t.Fatalf("Unable to load dataset, got error %v", err)
			}

			if len(testCase.deleteKeys) != 0 {
				err = cacheClient.Del(testCase.deleteKeys.List()...)
				if err != nil {
					t.Fatalf("Error delete keys, %v", err)
				}
			}

			if len(testCase.expireKeys) != 0 && testCase.expireDuration != 0 {
				for _, key := range testCase.expireKeys.List() {
					err = cacheClient.Expire(key, testCase.expireDuration)
					if err != nil {
						t.Fatalf("Error expire keys, %v", err)
					}
				}
				time.Sleep(testCase.expireDuration)
			}

			got, err := dump(cacheClient)
			if err != nil {
				t.Fatalf("Error dump data, %v", err)
			}

			if diff := cmp.Diff(got, testCase.expected); len(diff) != 0 {
				t.Errorf("%T differ (-got, +expected) %v", testCase.expected, diff)
			}
		})
	}
}