/*
Copyright 2017 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 wrappers

import (
	"context"
	"testing"

	"sigs.k8s.io/external-dns/endpoint"
	"sigs.k8s.io/external-dns/internal/testutils"
	"sigs.k8s.io/external-dns/source"
)

// Validates that dedupSource is a Source
var _ source.Source = &dedupSource{}

func TestDedup(t *testing.T) {
	t.Run("Endpoints", testDedupEndpoints)
}

// testDedupEndpoints tests that duplicates from the wrapped source are removed.
func testDedupEndpoints(t *testing.T) {
	for _, tc := range []struct {
		title     string
		endpoints []*endpoint.Endpoint
		expected  []*endpoint.Endpoint
	}{
		{
			"one endpoint returns one endpoint",
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
			},
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
			},
		},
		{
			"two different endpoints return two endpoints",
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "bar.example.org", Targets: endpoint.Targets{"4.5.6.7"}},
			},
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "bar.example.org", Targets: endpoint.Targets{"4.5.6.7"}},
			},
		},
		{
			"two endpoints with same dnsname and different targets return two endpoints",
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"4.5.6.7"}},
			},
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"4.5.6.7"}},
			},
		},
		{
			"two endpoints with different dnsname and same target return two endpoints",
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "bar.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
			},
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "bar.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
			},
		},
		{
			"two endpoints with same dnsname and same target return one endpoint",
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
			},
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
			},
		},
		{
			"two endpoints with same dnsname, same type, and same target return one endpoint",
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", RecordType: "A", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "foo.example.org", RecordType: "A", Targets: endpoint.Targets{"1.2.3.4"}},
			},
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", RecordType: "A", Targets: endpoint.Targets{"1.2.3.4"}},
			},
		},
		{
			"two endpoints with same dnsname, different record type, and same target return two endpoints",
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", RecordType: "A", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "foo.example.org", RecordType: "AAAA", Targets: endpoint.Targets{"1.2.3.4"}},
			},
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", RecordType: "A", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "foo.example.org", RecordType: "AAAA", Targets: endpoint.Targets{"1.2.3.4"}},
			},
		},
		{
			"two endpoints with same dnsname, one with record type, one without, and same target return two endpoints",
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", RecordType: "A", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
			},
			[]*endpoint.Endpoint{
				{DNSName: "foo.example.org", RecordType: "A", Targets: endpoint.Targets{"1.2.3.4"}},
				{DNSName: "foo.example.org", Targets: endpoint.Targets{"1.2.3.4"}},
			},
		},
	} {
		t.Run(tc.title, func(t *testing.T) {
			mockSource := new(testutils.MockSource)
			mockSource.On("Endpoints").Return(tc.endpoints, nil)

			// Create our object under test and get the endpoints.
			source := NewDedupSource(mockSource)

			endpoints, err := source.Endpoints(context.Background())
			if err != nil {
				t.Fatal(err)
			}

			// Validate returned endpoints against desired endpoints.
			validateEndpoints(t, endpoints, tc.expected)

			// Validate that the mock source was called.
			mockSource.AssertExpectations(t)
		})
	}
}
