Initial DDC release

internal/extract/formats.go

@@ -0,0 +1,50 @@
+package extract
+
+import "strings"
+
+type format int
+
+const (
+	formatNone format = iota
+	formatZip
+	formatTar
+	formatTarGzip
+	formatTarBzip2
+)
+
+var knownSuffixes = []struct {
+	suffix string
+	format format
+}{
+	{".tar.gz", formatTarGzip},
+	{".tgz", formatTarGzip},
+	{".tar.bz2", formatTarBzip2},
+	{".tbz2", formatTarBzip2},
+	{".tbz", formatTarBzip2},
+	{".tar", formatTar},
+	{".zip", formatZip},
+}
+
+func detect(name string) (format, string) {
+	lowerName := strings.ToLower(name)
+	for _, known := range knownSuffixes {
+		if strings.HasSuffix(lowerName, known.suffix) {
+			return known.format, known.suffix
+		}
+	}
+	return formatNone, ""
+}
+
+func IsArchive(name string) bool {
+	archiveFormat, _ := detect(name)
+	return archiveFormat != formatNone
+}
+
+func DirectoryName(archiveName string) string {
+	_, suffix := detect(archiveName)
+	base := strings.Trim(archiveName[:len(archiveName)-len(suffix)], ". ")
+	if base == "" {
+		return "extracted"
+	}
+	return base
+}