From 53f14d96ead5c331115065f238015538526e3964 Mon Sep 17 00:00:00 2001
From: Felix Ding <dingfeli@amazon.com>
Date: Thu, 21 Nov 2024 12:43:04 -0800
Subject: [PATCH] Adds command listeners for undo to control flag which signals
 to auto trigger whether or not to invoke queries (#256)

---
 .../util/AutoTriggerDocumentListener.java     | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/plugin/src/software/aws/toolkits/eclipse/amazonq/util/AutoTriggerDocumentListener.java b/plugin/src/software/aws/toolkits/eclipse/amazonq/util/AutoTriggerDocumentListener.java
index 19e0172c..e07ee0a3 100644
--- a/plugin/src/software/aws/toolkits/eclipse/amazonq/util/AutoTriggerDocumentListener.java
+++ b/plugin/src/software/aws/toolkits/eclipse/amazonq/util/AutoTriggerDocumentListener.java
@@ -3,14 +3,22 @@
 
 package software.aws.toolkits.eclipse.amazonq.util;
 
+import org.eclipse.core.commands.IExecutionListener;
 import org.eclipse.jface.text.DocumentEvent;
 import org.eclipse.jface.text.IDocumentListener;
+import org.eclipse.ui.PlatformUI;
+import org.eclipse.ui.commands.ICommandService;
 
 import static software.aws.toolkits.eclipse.amazonq.util.QEclipseEditorUtils.getActiveTextEditor;
 
 import java.util.concurrent.ExecutionException;
 
 public final class AutoTriggerDocumentListener implements IDocumentListener, IAutoTriggerListener {
+    private static final String UNDO_COMMAND_ID = "org.eclipse.ui.edit.undo";
+
+    private ThreadLocal<Boolean> isChangeInducedByUndo = ThreadLocal.withInitial(() -> false);
+    private IExecutionListener commandListener;
+
     public AutoTriggerDocumentListener() {
     }
 
@@ -45,17 +53,35 @@ private boolean shouldSendQuery(final DocumentEvent e, final QInvocationSession
             return false;
         }
 
+        if (isChangeInducedByUndo.get()) {
+            isChangeInducedByUndo.set(false);
+            return false;
+        }
+
         // TODO: implement other logic to prevent unnecessary firing
         return true;
     }
 
     @Override
     public void onStart() {
+        ICommandService commandService = PlatformUI.getWorkbench().getService(ICommandService.class);
+        commandListener = QEclipseEditorUtils.getAutoTriggerExecutionListener((commandId) -> undoCommandListenerCallback(commandId));
+        commandService.addExecutionListener(commandListener);
         return;
     }
 
     @Override
     public void onShutdown() {
+        if (commandListener != null) {
+            ICommandService commandService = PlatformUI.getWorkbench().getService(ICommandService.class);
+            commandService.removeExecutionListener(commandListener);
+        }
         return;
     }
+
+    private void undoCommandListenerCallback(final String commandId) {
+        if (commandId.equals(UNDO_COMMAND_ID)) {
+            isChangeInducedByUndo.set(true);
+        }
+    }
 }