almost there

spike/review/reinvent/ezmded/server/tree.go

@@ -9,8 +9,8 @@ import (
 )
 
 type Branch struct {
-	Leaf     Leaf
-	Branches map[string]Branch
+	Leaf     Leaf              `json:"Leaf,omitempty"`
+	Branches map[string]Branch `json:"Branches,omitempty"`
 }
 
 func (branch Branch) IsZero() bool {
@@ -29,6 +29,24 @@ func (branch Branch) Find(baseId string) ([]string, bool) {
 	return nil, false
 }
 
+func (branch Branch) ForEach(foo func([]string, Leaf) error) error {
+	return branch.forEach([]string{}, foo)
+}
+
+func (branch Branch) forEach(preid []string, foo func([]string, Leaf) error) error {
+	if err := foo(preid, branch.Leaf); err != nil {
+		return err
+	}
+	postid := append(preid, "")
+	for id, child := range branch.Branches {
+		postid[len(postid)-1] = id
+		if err := child.forEach(postid, foo); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 type Leaf struct {
 	Title   string
 	Deleted bool
@@ -39,6 +57,9 @@ func (base Leaf) Merge(updated Leaf) Leaf {
 	if updated.Title != "" {
 		base.Title = updated.Title
 	}
+	if base.Title == "" {
+		base.Title = "Untitled"
+	}
 	base.Deleted = updated.Deleted
 	base.Content = updated.Content
 	return base
@@ -55,6 +76,7 @@ func NewTree(root string) Tree {
 
 func (tree Tree) WithRoot(root string) Tree {
 	tree.root = root
+	tree.cachedRoot = Branch{}
 	return tree
 }