package config

import (
	"github.com/stretchr/testify/assert"
	"strconv"
	"sync"
	"testing"
)

const (
	telegramToken    = ":: telegram telegram token ::" //nolint:gosec // it is not real credentials
	telegramOwner    = 1234567890
	pathDictionaries = `docs/dictionaries`
)

func TestGetConfig(t *testing.T) { //nolint:paralleltest // because this test mock globals
	initTelegramBotEnvironment(t, telegramToken, telegramOwner, pathDictionaries)
	defer resetConfig(t)

	var config Config

	assert.NotPanics(t, func() { config = GetConfig() })

	assert.NotNil(t, config)
	assert.Equal(t, telegramToken, config.API.Token)
	assert.Equal(t, telegramOwner, config.API.Owner)
	assert.Equal(t, pathDictionaries, config.Paths.Docs)
}

func TestGetConfigTwice(t *testing.T) { //nolint:paralleltest // because this test mock globals
	initTelegramBotEnvironment(t, telegramToken, telegramOwner, pathDictionaries)
	defer resetConfig(t)

	config1 := GetConfig()
	config2 := GetConfig()

	assert.NotNil(t, config1)
	assert.NotNil(t, config2)
	assert.Equal(t, config1, config2)
	assert.NotSame(t, config1, config2)
}

func TestGetConfigAndSingletonIsImmutable(t *testing.T) { //nolint:paralleltest // because this test mock globals
	initTelegramBotEnvironment(t, telegramToken, telegramOwner, pathDictionaries)
	defer resetConfig(t)

	config1 := GetConfig()

	assert.Equal(t, telegramToken, config1.API.Token)
	assert.Equal(t, telegramOwner, config1.API.Owner)
	assert.Equal(t, pathDictionaries, config1.Paths.Docs)

	config1.API.Token = ":: some another telegram token ::"
	config1.API.Owner = 1
	config1.Paths.Docs = ":: some else path ::"
	config2 := GetConfig()

	assert.Equal(t, telegramToken, config2.API.Token)
	assert.Equal(t, telegramOwner, config2.API.Owner)
	assert.Equal(t, pathDictionaries, config2.Paths.Docs)
}

func TestGetConfigWithOnlyRequiredEnvironment(t *testing.T) { //nolint:paralleltest // because this test mock globals
	t.Setenv("TOKEN", telegramToken)
	t.Setenv("OWNER", strconv.Itoa(telegramOwner))

	resetConfig(t)
	defer resetConfig(t)

	config := GetConfig()

	assert.NotEmpty(t, config)
	assert.IsType(t, Config{}, config)
	assert.Equal(t, telegramToken, config.API.Token)
	assert.Equal(t, telegramOwner, config.API.Owner)
	assert.Equal(t, `docs`, config.Paths.Docs)
}

func TestGetConfigWithEmptyEnvironment(t *testing.T) { //nolint:paralleltest // because this test mock globals
	resetConfig(t)
	defer resetConfig(t)

	assert.Panics(t, func() { GetConfig() })
}

func initTelegramBotEnvironment(t *testing.T, telegramToken string, telegramOwner int, pathDictionaries string) {
	t.Helper()
	t.Setenv("TOKEN", telegramToken)
	t.Setenv("OWNER", strconv.Itoa(telegramOwner))
	t.Setenv("DOCS_PATH", pathDictionaries)
	resetConfig(t)
}

func resetConfig(t *testing.T) {
	t.Helper()

	cfg = Config{}
	once = sync.Once{}
}