// Copyright 2019 The Prometheus 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.

//go:build go1.21

package model

import (
	"encoding/json"
	"testing"
)

func TestUnmarshalJSONLabelSet(t *testing.T) {
	type testConfig struct {
		LabelSet LabelSet `yaml:"labelSet,omitempty"`
	}

	// valid LabelSet JSON
	labelSetJSON := `{
	"labelSet": {
		"monitor": "codelab",
		"foo": "bar",
		"foo2": "bar",
		"abc": "prometheus",
		"foo11": "bar11"
	}
}`
	var c testConfig
	err := json.Unmarshal([]byte(labelSetJSON), &c)
	if err != nil {
		t.Errorf("unexpected error while marshalling JSON : %s", err.Error())
	}

	labelSetString := c.LabelSet.String()

	expected := `{abc="prometheus", foo="bar", foo11="bar11", foo2="bar", monitor="codelab"}`

	if expected != labelSetString {
		t.Errorf("expected %s but got %s", expected, labelSetString)
	}

	// invalid LabelSet JSON
	invalidlabelSetJSON := `{
	"labelSet": {
		"1nvalid_23name": "codelab",
		"foo": "bar"
	}
}`

	NameValidationScheme = LegacyValidation
	err = json.Unmarshal([]byte(invalidlabelSetJSON), &c)
	expectedErr := `"1nvalid_23name" is not a valid label name`
	if err == nil || err.Error() != expectedErr {
		t.Errorf("expected an error with message '%s' to be thrown", expectedErr)
	}
}

func TestLabelSetClone(t *testing.T) {
	labelSet := LabelSet{
		"monitor": "codelab",
		"foo":     "bar",
		"bar":     "baz",
	}

	cloneSet := labelSet.Clone()

	if len(labelSet) != len(cloneSet) {
		t.Errorf("expected the length of the cloned Label set to be %d, but got %d",
			len(labelSet), len(cloneSet))
	}

	for ln, lv := range labelSet {
		expected := cloneSet[ln]
		if expected != lv {
			t.Errorf("expected to get LabelValue %s, but got %s for LabelName %s", expected, lv, ln)
		}
	}
}

func TestLabelSetMerge(t *testing.T) {
	labelSet := LabelSet{
		"monitor": "codelab",
		"foo":     "bar",
		"bar":     "baz",
	}

	labelSet2 := LabelSet{
		"monitor": "codelab",
		"dolor":   "mi",
		"lorem":   "ipsum",
	}

	expectedSet := LabelSet{
		"monitor": "codelab",
		"foo":     "bar",
		"bar":     "baz",
		"dolor":   "mi",
		"lorem":   "ipsum",
	}

	mergedSet := labelSet.Merge(labelSet2)

	if len(mergedSet) != len(expectedSet) {
		t.Errorf("expected the length of the cloned Label set to be %d, but got %d",
			len(expectedSet), len(mergedSet))
	}

	for ln, lv := range mergedSet {
		expected := expectedSet[ln]
		if expected != lv {
			t.Errorf("expected to get LabelValue %s, but got %s for LabelName %s", expected, lv, ln)
		}
	}
}

func TestLabelSet_String(t *testing.T) {
	tests := []struct {
		input LabelSet
		want  string
	}{
		{
			input: nil,
			want:  `{}`,
		}, {
			input: LabelSet{
				"foo": "bar",
			},
			want: `{foo="bar"}`,
		}, {
			input: LabelSet{
				"foo":   "bar",
				"foo2":  "bar",
				"abc":   "prometheus",
				"foo11": "bar11",
			},
			want: `{abc="prometheus", foo="bar", foo11="bar11", foo2="bar"}`,
		},
	}
	for _, tt := range tests {
		t.Run("test", func(t *testing.T) {
			if got := tt.input.String(); got != tt.want {
				t.Errorf("LabelSet.String() = %v, want %v", got, tt.want)
			}
		})
	}
}

// Benchmark Results for LabelSet's String() method
// ---------------------------------------------------------------------------------------------------------
// goos: linux
// goarch: amd64
// pkg: github.com/prometheus/common/model
// cpu: 11th Gen Intel(R) Core(TM) i5-1145G7 @ 2.60GHz
// BenchmarkLabelSetStringMethod-8                               732376              1532 ns/op

func BenchmarkLabelSetStringMethod(b *testing.B) {
	ls := make(LabelSet)
	ls["monitor"] = "codelab"
	ls["foo2"] = "bar"
	ls["foo"] = "bar"
	ls["abc"] = "prometheus"
	ls["foo11"] = "bar11"
	for i := 0; i < b.N; i++ {
		_ = ls.String()
	}
}