From 3a1644b734f4c801800bf0d478062789a5680f15 Mon Sep 17 00:00:00 2001
From: Rasmus Andersson <rasmus@notion.se>
Date: Tue, 1 Feb 2011 14:13:21 +0100
Subject: [PATCH] added an "edit" event in node.js-land emitted from documents
 (with version, location and change delta values)

---
 resources/main.js               | 21 +++++++++++++++++++++
 src/KDocument.mm                | 32 +++++++++++++++++++++++++++++++-
 src/node-module/KObjectProxy.mm |  2 ++
 3 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/resources/main.js b/resources/main.js
index 17e4e3c..f2f356c 100644
--- a/resources/main.js
+++ b/resources/main.js
@@ -64,6 +64,27 @@ kod.on('openDocument', function(document) {
   //console.log('openDocument: '+ util.inspect(document, 0, 4));
   console.log('openDocument: #'+document.identifier+' '+document.type+
               ' '+(document.url || '*new*'));
+
+  // example of registering for the "edit" event, emitted after each edit to
+  // a document.
+  /*document.on('edit', function(version, location, changeDelta) {
+    console.log(this+':edit -> %j', {
+      version:version, location:location, changeDelta:changeDelta});
+    // if we are to manipulate the text, we need to compare versions since
+    // these things happen concurrently. Here, we wrap a "p" character in < & >:
+    if (document.version == version && changeDelta == 1) {
+      var text = document.text;
+      var changedChar = text.substr(location, 1);
+      if (changedChar == "p") {
+        document.text = text.substr(0,location)+'<'+changedChar+'>'+
+                        text.substr(location+1);
+        if (document.version != version+1) {
+          console.log("another edit happened while we where running. "+
+                      "The effect is undefined from our perspective.");
+        }
+      }
+    }
+  })*/
 });
 
 // example event listener for the "activateDocument" event, emitted when a
diff --git a/src/KDocument.mm b/src/KDocument.mm
index 5f60029..3c02e80 100644
--- a/src/KDocument.mm
+++ b/src/KDocument.mm
@@ -1358,7 +1358,7 @@ - (void)textStorageDidProcessEditing:(NSNotification *)notification {
 
   // Increment our version
   [self willChangeValueForKey:@"version"];
-  h_atomic_inc(&version_);
+  uint64_t version = h_atomic_inc(&version_);
   [self didChangeValueForKey:@"version"];
 
   // range that was affected by the edit
@@ -1382,6 +1382,36 @@ - (void)textStorageDidProcessEditing:(NSNotification *)notification {
     });
   }
 
+  // emit event in node-land
+  KNodePerformInNode(^(KNodeReturnBlock returnCallback){
+    v8::HandleScope scope;
+    v8::Local<v8::Object> doc = [self v8Value]->ToObject();
+    // TODO: refactor this to be reusable for emitting events on any object
+    v8::Local<v8::Value> emitV = doc->Get(v8::String::New("emit"));
+    if (!emitV.IsEmpty() && emitV->IsFunction()) {
+      v8::Local<v8::Value> argv[] = {
+        v8::String::New("edit"),
+        v8::Number::New((double)version),
+        v8::Number::New((double)editedRange.location),
+        v8::Integer::New(changeInLength)
+      };
+      static const int argc = sizeof(argv) / sizeof(argv[0]);
+      v8::TryCatch tryCatch;
+      v8::Local<v8::Value> returnValue =
+          v8::Local<v8::Function>::Cast(emitV)->Call(doc, argc, argv);
+      NSError *error = nil;
+      if (tryCatch.HasCaught()) {
+        v8::String::Utf8Value trace(tryCatch.StackTrace());
+        NSAutoreleasePool *pool1 = [NSAutoreleasePool new];
+        WLOG("Error while emitting event '%s' on %@: %s", "edit", self,
+             *trace ? *trace : "(no trace)");
+        [pool1 drain];
+      }
+    }
+    // must be called since this takes care of releasing some resources
+    returnCallback(nil, nil, nil);
+  });
+
   // we do not process edits when we are loading
   if (isLoading_) return;
 
diff --git a/src/node-module/KObjectProxy.mm b/src/node-module/KObjectProxy.mm
index c22a17c..548b4f7 100644
--- a/src/node-module/KObjectProxy.mm
+++ b/src/node-module/KObjectProxy.mm
@@ -32,6 +32,8 @@ @interface _KObjectProxyShelf : NSObject {} @end
 @implementation _KObjectProxyShelf
 - (void)_KObjectProxy_dealloc_associations {
   //DLOG("_KObjectProxy_dealloc_associations for %p", self);
+  // TODO: assert that we are running in the nodejs thread, or we need to
+  // defer this to that thread since v8 will crash and burn unless so.
 
   // clear wrapper
   NSValue *v = objc_getAssociatedObject(self, &kPersistentWrapperKey);