refactor scanner

scanner/folder_stack.go

@@ -0,0 +1,35 @@
+package scanner
+
+import "github.com/sentriz/gonic/model"
+
+type folderStack []*model.Folder
+
+func (s *folderStack) Push(v *model.Folder) {
+	*s = append(*s, v)
+}
+
+func (s *folderStack) Pop() *model.Folder {
+	l := len(*s)
+	if l == 0 {
+		return nil
+	}
+	r := (*s)[l-1]
+	*s = (*s)[:l-1]
+	return r
+}
+
+func (s *folderStack) Peek() *model.Folder {
+	l := len(*s)
+	if l == 0 {
+		return nil
+	}
+	return (*s)[l-1]
+}
+
+func (s *folderStack) PeekID() int {
+	l := len(*s)
+	if l == 0 {
+		return 0
+	}
+	return (*s)[l-1].ID
+}