Initial DDC release

internal/files/size.go

@@ -0,0 +1,52 @@
+package files
+
+import (
+	"errors"
+	"fmt"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+func TreeSize(root string) (int64, error) {
+	var total int64
+	err := filepath.WalkDir(root, func(_ string, entry fs.DirEntry, walkErr error) error {
+		if walkErr != nil {
+			return walkErr
+		}
+		if !entry.Type().IsRegular() {
+			return nil
+		}
+		info, err := entry.Info()
+		if err != nil {
+			return err
+		}
+		total += info.Size()
+		return nil
+	})
+	return total, err
+}
+
+func UniquePath(candidate string) string {
+	if !exists(candidate) {
+		return candidate
+	}
+
+	directory, name := filepath.Split(candidate)
+	extension := filepath.Ext(name)
+	base := strings.TrimSuffix(name, extension)
+	for index := 1; index < 1000; index++ {
+		next := filepath.Join(directory, fmt.Sprintf("%s (%d)%s", base, index, extension))
+		if !exists(next) {
+			return next
+		}
+	}
+	return filepath.Join(directory, fmt.Sprintf("%s-%d%s", base, time.Now().UnixNano(), extension))
+}
+
+func exists(path string) bool {
+	_, err := os.Lstat(path)
+	return !errors.Is(err, fs.ErrNotExist)
+}