qml: fix hang in ChatView by processing text explicitly (#2543)

Fixes #2519

Signed-off-by: Adam Treat <treat.adam@gmail.com>
Signed-off-by: Jared Van Bortel <jared@nomic.ai>
Co-authored-by: Jared Van Bortel <jared@nomic.ai>

gpt4all-chat/chatmodel.h

@@ -188,11 +188,6 @@ public:
         }
     }
 
-    Q_INVOKABLE void forceUpdate(int index)
-    {
-        emit dataChanged(createIndex(index, 0), createIndex(index, 0), {ValueRole});
-    }
-
     Q_INVOKABLE void updateValue(int index, const QString &value)
     {
         if (index < 0 || index >= m_chatItems.size()) return;
@@ -201,6 +196,7 @@ public:
         if (item.value != value) {
             item.value = value;
             emit dataChanged(createIndex(index, 0), createIndex(index, 0), {ValueRole});
+            emit valueChanged(index, value);
         }
     }
 
@@ -468,6 +464,7 @@ public:
 
 Q_SIGNALS:
     void countChanged();
+    void valueChanged(int index, const QString &value);
 
 private:
 

gpt4all-chat/chatviewtextprocessor.cpp

@@ -771,9 +771,8 @@ void SyntaxHighlighter::highlightBlock(const QString &text)
 // chat class to populate the clipboard.
 ChatViewTextProcessor::ChatViewTextProcessor(QObject *parent)
     : QObject{parent}
-    , m_textDocument(nullptr)
+    , m_quickTextDocument(nullptr)
     , m_syntaxHighlighter(new SyntaxHighlighter(this))
-    , m_isProcessingText(false)
     , m_shouldProcessText(true)
     , m_fontPixelSize(QGuiApplication::font().pointSizeF())
 {
@@ -781,17 +780,19 @@ ChatViewTextProcessor::ChatViewTextProcessor(QObject *parent)
 
 QQuickTextDocument* ChatViewTextProcessor::textDocument() const
 {
-    return m_textDocument;
+    return m_quickTextDocument;
 }
 
-void ChatViewTextProcessor::setTextDocument(QQuickTextDocument* textDocument)
+void ChatViewTextProcessor::setTextDocument(QQuickTextDocument* quickTextDocument)
 {
-    if (m_textDocument)
+    m_quickTextDocument = quickTextDocument;
-        disconnect(m_textDocument->textDocument(), &QTextDocument::contentsChanged, this, &ChatViewTextProcessor::handleTextChanged);
+    m_syntaxHighlighter->setDocument(m_quickTextDocument->textDocument());
+    handleTextChanged();
+}
 
-    m_textDocument = textDocument;
+void ChatViewTextProcessor::setValue(const QString &value)
-    m_syntaxHighlighter->setDocument(m_textDocument->textDocument());
+{
-    connect(m_textDocument->textDocument(), &QTextDocument::contentsChanged, this, &ChatViewTextProcessor::handleTextChanged);
+    m_quickTextDocument->textDocument()->setPlainText(value);
     handleTextChanged();
 }
 
@@ -881,14 +882,12 @@ void traverseDocument(QTextDocument *doc, QTextFrame *frame)
 
 void ChatViewTextProcessor::handleTextChanged()
 {
-    if (!m_textDocument || m_isProcessingText || !m_shouldProcessText)
+    if (!m_quickTextDocument || !m_shouldProcessText)
         return;
 
-    m_isProcessingText = true;
-
     // Force full layout of the text document to work around a bug in Qt
     // TODO(jared): report the Qt bug and link to the report here
-    QTextDocument* doc = m_textDocument->textDocument();
+    QTextDocument* doc = m_quickTextDocument->textDocument();
     (void)doc->documentLayout()->documentSize();
 
     handleCodeBlocks();
@@ -899,12 +898,11 @@ void ChatViewTextProcessor::handleTextChanged()
     QTextCursor cursor(doc);
     QString invisibleCharacter = QString(QChar(0xFEFF));
     cursor.insertText(invisibleCharacter, QTextCharFormat());
-    m_isProcessingText = false;
 }
 
 void ChatViewTextProcessor::handleCodeBlocks()
 {
-    QTextDocument* doc = m_textDocument->textDocument();
+    QTextDocument* doc = m_quickTextDocument->textDocument();
     QTextCursor cursor(doc);
 
     QTextCharFormat textFormat;
@@ -1081,7 +1079,7 @@ void replaceAndInsertMarkdown(int startIndex, int endIndex, QTextDocument *doc)
 
 void ChatViewTextProcessor::handleMarkdown()
 {
-    QTextDocument* doc = m_textDocument->textDocument();
+    QTextDocument* doc = m_quickTextDocument->textDocument();
     QTextCursor cursor(doc);
 
     QVector<QPair<int, int>> codeBlockPositions;

gpt4all-chat/chatviewtextprocessor.h

@@ -96,6 +96,7 @@ public:
     QQuickTextDocument* textDocument() const;
     void setTextDocument(QQuickTextDocument* textDocument);
 
+    Q_INVOKABLE void setValue(const QString &value);
     Q_INVOKABLE bool tryCopyAtPosition(int position) const;
 
     bool shouldProcessText() const;
@@ -119,12 +120,11 @@ private Q_SLOTS:
     void handleMarkdown();
 
 private:
-    QQuickTextDocument *m_textDocument;
+    QQuickTextDocument *m_quickTextDocument;
     SyntaxHighlighter *m_syntaxHighlighter;
     QVector<ContextLink> m_links;
     QVector<CodeCopy> m_copies;
     bool m_shouldProcessText = false;
-    bool m_isProcessingText = false;
     qreal m_fontPixelSize;
 };
 

gpt4all-chat/qml/ChatView.qml

@@ -879,7 +879,6 @@ Rectangle {
                                     Layout.fillWidth: true
                                     TextArea {
                                         id: myTextArea
-                                        text: value
                                         Layout.fillWidth: true
                                         padding: 0
                                         color: {
@@ -953,7 +952,7 @@ Rectangle {
                                                 height: enabled ? implicitHeight : 0
                                                 onTriggered: {
                                                     textProcessor.shouldProcessText = !textProcessor.shouldProcessText;
-                                                    myTextArea.text = value
+                                                    textProcessor.setValue(value);
                                                 }
                                             }
                                         }
@@ -974,11 +973,16 @@ Rectangle {
                                             textProcessor.codeColors.headerColor       = theme.codeHeaderColor
                                             textProcessor.codeColors.backgroundColor   = theme.codeBackgroundColor
                                             textProcessor.textDocument                 = textDocument
-                                            chatModel.forceUpdate(index); // called to trigger a reprocessing of the text
+                                            textProcessor.setValue(value);
                                         }
 
                                         Component.onCompleted: {
                                             resetChatViewTextProcessor();
+                                            chatModel.valueChanged.connect(function(i, value) {
+                                                if (index === i)
+                                                    textProcessor.setValue(value);
+                                                }
+                                            );
                                         }
 
                                         Connections {

gpt4all-chat/qml/HomeView.qml

@@ -272,7 +272,7 @@ Rectangle {
         color: theme.conversationBackground
         width: subscribeLink.width
         RowLayout {
-            anchors.fill: parent
+            anchors.centerIn: parent
             MyFancyLink {
                 id: subscribeLink
                 Layout.alignment: Qt.AlignCenter