package config_test

import (
	"FamilyHub/src/config"
	"os"
	"testing"

	"github.com/stretchr/testify/assert"
)

type EnvFixture struct {
	backup map[string]string
}

func NewEnvFixture() *EnvFixture {
	env := make(map[string]string)

	for _, e := range os.Environ() {
		pair := split(e)
		env[pair[0]] = pair[1]
	}

	// полностью чистое окружение
	os.Clearenv()
	return &EnvFixture{backup: env}
}

func (e *EnvFixture) Restore() {
	os.Clearenv()
	for key, val := range e.backup {
		_ = os.Setenv(key, val)
	}
}

func split(s string) [2]string {
	var p [2]string
	for i := 0; i < len(s); i++ {
		if s[i] == '=' {
			p[0] = s[:i]
			p[1] = s[i+1:]
			return p
		}
	}
	return p
}

func MustSet(env map[string]string) {
	for k, v := range env {
		_ = os.Setenv(k, v)
	}
}

func MustUnset(keys ...string) {
	for _, k := range keys {
		_ = os.Unsetenv(k)
	}
}

func TestConfigLoad_Table(t *testing.T) {
	env := NewEnvFixture()
	defer env.Restore()

	tests := []struct {
		name  string
		env   map[string]string
		want  config.Config
		error bool
	}{
		{
			name: "ok - values set",
			env:  map[string]string{"BOT_TOKEN": "abc", "DB_PATH": "db.sqlite"},
			want: config.Config{BotToken: "abc", DBConnectionString: "db.sqlite"},
		},
		{
			name:  "fail - missing token",
			env:   map[string]string{}, // ничего нет
			error: true,
		},
		{
			name:  "default DB path applied",
			env:   map[string]string{"BOT_TOKEN": "xyz"},
			error: true,
		},
	}

	for _, tc := range tests {
		testCase := tc
		t.Run(testCase.name, func(t *testing.T) {
			t.Parallel()

			os.Clearenv()
			MustSet(testCase.env)

			cfg, err := config.Load()

			if testCase.error {
				assert.Error(t, err)
				return
			}

			assert.NoError(t, err)
			assert.Equal(t, testCase.want.BotToken, cfg.BotToken)
			assert.Equal(t, testCase.want.DBConnectionString, cfg.DBConnectionString)
		})
	}
}