package modernzconf

import (
	"path/filepath"
	"sync"
	"testing"
)

func TestSetValueFileConcurrentUpdatesPreserveEveryOption(t *testing.T) {
	path := filepath.Join(t.TempDir(), "modernz.conf")
	options := KnownOptions()
	if len(options) < 2 {
		t.Fatal("expected at least two ModernZ options")
	}

	start := make(chan struct{})
	errs := make(chan error, len(options))
	var wg sync.WaitGroup
	for _, option := range options {
		option := option
		wg.Add(1)
		go func() {
			defer wg.Done()
			<-start
			if err := SetValueFile(path, option.Key, option.Default); err != nil {
				errs <- err
			}
		}()
	}
	close(start)
	wg.Wait()
	close(errs)
	for err := range errs {
		t.Fatal(err)
	}

	conf, err := ParseModernZConf(path)
	if err != nil {
		t.Fatal(err)
	}
	for _, option := range options {
		if !conf.IsSet(option.Key) {
			t.Errorf("concurrent update lost option %q", option.Key)
		}
	}
}