package cluster

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

func TestEnsureNodeID_GeneratesAndPersists(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "node-id")

	id1, err := EnsureNodeID(path)
	if err != nil {
		t.Fatalf("first call: %v", err)
	}
	if !validNodeID(id1) {
		t.Fatalf("invalid node id minted: %q", id1)
	}

	id2, err := EnsureNodeID(path)
	if err != nil {
		t.Fatalf("second call: %v", err)
	}
	if id1 != id2 {
		t.Errorf("node id should be stable: %q vs %q", id1, id2)
	}
}

func TestEnsureNodeID_RejectsCorruptFile(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "node-id")
	if err := os.WriteFile(path, []byte("not a real id\n"), 0o640); err != nil {
		t.Fatal(err)
	}
	id, err := EnsureNodeID(path)
	if err != nil {
		t.Fatalf("EnsureNodeID: %v", err)
	}
	if !validNodeID(id) {
		t.Errorf("expected fresh id when file was junk, got %q", id)
	}
	// Re-read should now match the regenerated id.
	id2, _ := EnsureNodeID(path)
	if id != id2 {
		t.Errorf("regenerated id not persisted: %q vs %q", id, id2)
	}
}