package config

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

func TestGetConfig(t *testing.T) {
	telegramToken := ":: telegram telegram token ::"
	telegramOwner := 1234567890
	pathDictionaries := `docs/dictionaries`

	initTelegramBotEnvironment(telegramToken, telegramOwner, pathDictionaries)
	defer cleanTelegramBotEnvironment()

	var config Config
	assert.NotPanics(t, func() { 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, pathDictionaries, config.Paths.Docs)
}

func TestGetConfigTwice(t *testing.T) {
	initTelegramBotEnvironment(":: telegram telegram token ::", 1234567890, `docs/dictionaries`)
	defer cleanTelegramBotEnvironment()

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

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

func TestGetConfigAndSingletonIsImmutable(t *testing.T) {
	telegramToken := ":: telegram telegram token ::"
	telegramOwner := 1234567890
	pathDictionaries := `docs/dictionaries`

	initTelegramBotEnvironment(telegramToken, telegramOwner, pathDictionaries)
	defer cleanTelegramBotEnvironment()

	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) {
	telegramToken := ":: telegram telegram token ::"
	telegramOwner := 1234567890

	_ = os.Setenv("TOKEN", telegramToken)
	_ = os.Setenv("OWNER", strconv.Itoa(telegramOwner))
	defer cleanTelegramBotEnvironment()

	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) {
	cleanTelegramBotEnvironment()

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

func initTelegramBotEnvironment(telegramToken string, telegramOwner int, pathDictionaries string) {
	resetConfig()
	_ = os.Setenv("TOKEN", telegramToken)
	_ = os.Setenv("OWNER", strconv.Itoa(telegramOwner))
	_ = os.Setenv("DOCS_PATH", pathDictionaries)
}

func cleanTelegramBotEnvironment() {
	_ = os.Unsetenv("TOKEN")
	_ = os.Unsetenv("OWNER")
	_ = os.Unsetenv("DOCS_PATH")
	resetConfig()
}

func resetConfig()  {
	cfg = Config{}
	once = sync.Once{}
}