dirtree: add dirtree-collapse config setting

Adds a setting to the configuration to choose at which level the
folders in the dirtree are collapsed by default.

In my case, this is useful because my organisation has some rather deep
nesting in the folder structure, and a _lot_ of folders, and this way I
can keep my dirtree uncluttered while still having all folders there if
I need them.

Signed-off-by: Sijmen <me@sijman.nl>
Acked-by: Koni Marti <koni.marti@gmail.com>

widgets/dirtree.go

@@ -327,7 +327,7 @@ func (dt *DirectoryTree) buildTree() {
 	copy(dt.treeDirs, dt.dirs)
 
 	root := &types.Thread{Uid: 0}
-	buildTree(root, sTree, 0xFFFFFF)
+	dt.buildTreeNode(root, sTree, 0xFFFFFF, 1)
 
 	threads := make([]*types.Thread, 0)
 
@@ -373,7 +373,7 @@ func (dt *DirectoryTree) buildTree() {
 	}
 }
 
-func buildTree(node *types.Thread, stree [][]string, defaultUid uint32) {
+func (dt *DirectoryTree) buildTreeNode(node *types.Thread, stree [][]string, defaultUid uint32, depth int) {
 	m := make(map[string][][]string)
 	for _, branch := range stree {
 		if len(branch) > 1 {
@@ -398,7 +398,10 @@ func buildTree(node *types.Thread, stree [][]string, defaultUid uint32) {
 		}
 		nextNode := &types.Thread{Uid: uid}
 		node.AddChild(nextNode)
-		buildTree(nextNode, next, defaultUid)
+		if dt.UiConfig().DirListCollapse != 0 {
+			node.Hidden = depth > dt.UiConfig().DirListCollapse
+		}
+		dt.buildTreeNode(nextNode, next, defaultUid, depth+1)
 	}
 }