package main

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

func TestRenameProbeOKSameFilesystem(t *testing.T) {
	tmpDir := t.TempDir()
	targetDir := t.TempDir()
	if err := renameProbeOK(tmpDir, targetDir); err != nil {
		t.Fatalf("same-filesystem probe: %s", err)
	}
	// No litter: probe file removed, nothing else created.
	entries, err := os.ReadDir(targetDir)
	if err != nil {
		t.Fatal(err)
	}
	if len(entries) != 0 {
		t.Errorf("probe left %d entries in target dir", len(entries))
	}
	entries, err = os.ReadDir(tmpDir)
	if err != nil {
		t.Fatal(err)
	}
	if len(entries) != 0 {
		t.Errorf("probe left %d entries in tmp dir", len(entries))
	}
}

func TestRenameProbeFailsClosed(t *testing.T) {
	tmpDir := t.TempDir()

	t.Run("missing tmp dir", func(t *testing.T) {
		if err := renameProbeOK(filepath.Join(tmpDir, "nope"), tmpDir); err == nil {
			t.Error("expected error for missing tmp dir, got nil")
		}
	})

	t.Run("unwritable target dir", func(t *testing.T) {
		targetDir := t.TempDir()
		if err := os.Chmod(targetDir, 0o500); err != nil {
			t.Fatal(err)
		}
		defer os.Chmod(targetDir, 0o700)
		if err := renameProbeOK(tmpDir, targetDir); err == nil {
			t.Error("expected error for unwritable target dir, got nil")
		}
	})

	t.Run("missing target dir", func(t *testing.T) {
		if err := renameProbeOK(tmpDir, filepath.Join(tmpDir, "nope")); err == nil {
			t.Error("expected error for missing target dir, got nil")
		}
	})
}