From fd14757c04f894919e014629fcec91de3c34892c Mon Sep 17 00:00:00 2001
From: Martin Grenfell <martin.grenfell@gmail.com>
Date: Thu, 17 Jul 2014 20:16:57 +0100
Subject: [PATCH] add proper events and make the notifier class generic

Expand the event system to have explicit Event objects and potentially
many Notifiers. Previously they was only one notifier and one (implied)
event.

A lot of this is stolen from #358.
---
 autoload/nerdtree.vim             |  3 ++-
 lib/nerdtree/event.vim            | 13 ++++++++++++
 lib/nerdtree/notifier.vim         | 35 +++++++++++++++++++++++++++++++
 lib/nerdtree/path.vim             |  4 ++--
 lib/nerdtree/refresh_notifier.vim | 21 -------------------
 lib/nerdtree/tree_dir_node.vim    |  2 +-
 6 files changed, 53 insertions(+), 25 deletions(-)
 create mode 100644 lib/nerdtree/event.vim
 create mode 100644 lib/nerdtree/notifier.vim
 delete mode 100644 lib/nerdtree/refresh_notifier.vim

diff --git a/autoload/nerdtree.vim b/autoload/nerdtree.vim
index 618328e..7f588b8 100644
--- a/autoload/nerdtree.vim
+++ b/autoload/nerdtree.vim
@@ -74,10 +74,11 @@ function! nerdtree#loadClassFiles()
     runtime lib/nerdtree/tree_dir_node.vim
     runtime lib/nerdtree/opener.vim
     runtime lib/nerdtree/creator.vim
-    runtime lib/nerdtree/refresh_notifier.vim
     runtime lib/nerdtree/flag_set.vim
     runtime lib/nerdtree/nerdtree.vim
     runtime lib/nerdtree/ui.vim
+    runtime lib/nerdtree/event.vim
+    runtime lib/nerdtree/notifier.vim
 endfunction
 
 " FUNCTION: nerdtree#postSourceActions() {{{2
diff --git a/lib/nerdtree/event.vim b/lib/nerdtree/event.vim
new file mode 100644
index 0000000..964e8ff
--- /dev/null
+++ b/lib/nerdtree/event.vim
@@ -0,0 +1,13 @@
+"CLASS: Event
+"============================================================
+let s:Event = {}
+let g:NERDTreeEvent = s:Event
+
+function! s:Event.New(nerdtree, subject, action, params) abort
+    let newObj = copy(self)
+    let newObj.nerdtree = a:nerdtree
+    let newObj.subject = a:subject
+    let newObj.action = a:action
+    let newObj.params = a:params
+    return newObj
+endfunction
diff --git a/lib/nerdtree/notifier.vim b/lib/nerdtree/notifier.vim
new file mode 100644
index 0000000..b445f8a
--- /dev/null
+++ b/lib/nerdtree/notifier.vim
@@ -0,0 +1,35 @@
+"CLASS: Notifier
+"============================================================
+let s:Notifier = {}
+
+function! s:Notifier.AddListener(event, funcname)
+    let listeners = s:Notifier.GetListenersForEvent(a:event)
+    if listeners == []
+        let listenersMap = s:Notifier.GetListenersMap()
+        let listenersMap[a:event] = listeners
+    endif
+    call add(listeners, a:funcname)
+endfunction
+
+function! s:Notifier.NotifyListeners(event, path, params)
+    let event = g:NERDTreeEvent.New(b:NERDTree, a:path, a:event, a:params)
+
+    for listener in s:Notifier.GetListenersForEvent(a:event)
+        call {listener}(event)
+    endfor
+endfunction
+
+function! s:Notifier.GetListenersMap()
+    if !exists("s:refreshListenersMap")
+        let s:refreshListenersMap = {}
+    endif
+    return s:refreshListenersMap
+endfunction
+
+function! s:Notifier.GetListenersForEvent(name)
+    let listenersMap = s:Notifier.GetListenersMap()
+    return get(listenersMap, a:name, [])
+endfunction
+
+let g:NERDTreePathNotifier = deepcopy(s:Notifier)
+
diff --git a/lib/nerdtree/path.vim b/lib/nerdtree/path.vim
index 5ab6b49..5de1dfe 100644
--- a/lib/nerdtree/path.vim
+++ b/lib/nerdtree/path.vim
@@ -549,13 +549,13 @@ endfunction
 "FUNCTION: Path.refresh() {{{1
 function! s:Path.refresh()
     call self.readInfoFromDisk(self.str())
-    call g:NERDTreeRefreshNotifier.NotifyListeners(self)
+    call g:NERDTreePathNotifier.NotifyListeners('refresh', self, {})
     call self.cacheDisplayString()
 endfunction
 
 "FUNCTION: Path.refreshFlags() {{{1
 function! s:Path.refreshFlags()
-    call g:NERDTreeRefreshNotifier.NotifyListeners(self)
+    call g:NERDTreePathNotifier.NotifyListeners('refreshFlags', self, {})
     call self.cacheDisplayString()
 endfunction
 
diff --git a/lib/nerdtree/refresh_notifier.vim b/lib/nerdtree/refresh_notifier.vim
deleted file mode 100644
index 0cc62b0..0000000
--- a/lib/nerdtree/refresh_notifier.vim
+++ /dev/null
@@ -1,21 +0,0 @@
-"CLASS: RefreshNotifier
-"============================================================
-let s:RefreshNotifier = {}
-let g:NERDTreeRefreshNotifier = s:RefreshNotifier
-
-function! s:RefreshNotifier.AddListener(funcname)
-    call add(s:RefreshNotifier.GetListeners(), a:funcname)
-endfunction
-
-function! s:RefreshNotifier.NotifyListeners(refreshedPath)
-    for listener in s:RefreshNotifier.GetListeners()
-        call {listener}(a:refreshedPath)
-    endfor
-endfunction
-
-function! s:RefreshNotifier.GetListeners()
-    if !exists("s:refreshListeners")
-        let s:refreshListeners = []
-    endif
-    return s:refreshListeners
-endfunction
diff --git a/lib/nerdtree/tree_dir_node.vim b/lib/nerdtree/tree_dir_node.vim
index e7cc846..3f11e93 100644
--- a/lib/nerdtree/tree_dir_node.vim
+++ b/lib/nerdtree/tree_dir_node.vim
@@ -252,7 +252,7 @@ function! s:TreeDirNode._initChildren(silent)
             try
                 let path = g:NERDTreePath.New(i)
                 call self.createChild(path, 0)
-                call g:NERDTreeRefreshNotifier.NotifyListeners(path)
+                call g:NERDTreePathNotifier.NotifyListeners('init', path, {})
             catch /^NERDTree.\(InvalidArguments\|InvalidFiletype\)Error/
                 let invalidFilesFound += 1
             endtry