TextEditor: filter suggestions while typing

This will remove suggestions that are no longer applyable with the
current editor content.

Change-Id: Ibfc47495d5dda99a9ef2d7fe3f69c83a2d7e3997
Reviewed-by: <lie@spyro-soft.com>
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>

src/plugins/copilot/copilotplugin.cpp

@@ -45,7 +45,6 @@ static void cycleSuggestion(TextEditor::TextEditorWidget *editor, Direction dire
             index = suggestion->suggestions().count() - 1;
         else if (index >= suggestion->suggestions().count())
             index = 0;
-        suggestion->reset();
         editor->insertSuggestion(std::make_unique<TextEditor::CyclicSuggestion>(
             suggestion->suggestions(), editor->document(), index));
     }

src/plugins/texteditor/textdocumentlayout.cpp

@@ -608,26 +608,6 @@ void TextDocumentLayout::updateSuggestionFormats(const QTextBlock &block,
     }
 }
 
-bool TextDocumentLayout::updateSuggestion(const QTextBlock &block,
-                                          int position,
-                                          const FontSettings &fontSettings)
-{
-    if (TextSuggestion *suggestion = TextDocumentLayout::suggestion(block)) {
-        if (position < suggestion->currentPosition())
-            return false;
-        const int positionInBlock = position - block.position();
-        const QString start = block.text().left(positionInBlock);
-        const QString end = block.text().mid(positionInBlock);
-        const QString replacement = suggestion->replacementDocument()->firstBlock().text();
-        if (replacement.startsWith(start) && replacement.indexOf(end, start.size()) >= 0) {
-            suggestion->setCurrentPosition(position);
-            TextDocumentLayout::updateSuggestionFormats(block, fontSettings);
-            return true;
-        }
-    }
-    return false;
-}
-
 void TextDocumentLayout::requestExtraAreaUpdate()
 {
     emit updateExtraArea();

src/plugins/texteditor/textdocumentlayout.h

@@ -188,9 +188,6 @@ public:
     static quint8 attributeState(const QTextBlock &block);
     static void updateSuggestionFormats(const QTextBlock &block,
                                         const FontSettings &fontSettings);
-    static bool updateSuggestion(const QTextBlock &block,
-                                 int position,
-                                 const FontSettings &fontSettings);
 
     class TEXTEDITOR_EXPORT FoldValidator
     {

src/plugins/texteditor/texteditor.cpp

@@ -1836,16 +1836,23 @@ void TextEditorWidgetPrivate::updateSuggestion()
 {
     if (!m_suggestionBlock.isValid())
         return;
-    if (m_cursors.mainCursor().block() != m_suggestionBlock) {
-        clearCurrentSuggestion();
-    } else {
-        if (!TextDocumentLayout::updateSuggestion(m_suggestionBlock,
-                                                  m_cursors.mainCursor().position(),
-                                                  m_document->fontSettings())) {
-            clearCurrentSuggestion();
+    const QTextCursor cursor = m_cursors.mainCursor();
+    if (cursor.block() == m_suggestionBlock) {
+        TextSuggestion *suggestion = TextDocumentLayout::suggestion(m_suggestionBlock);
+        if (QTC_GUARD(suggestion)) {
+            const int pos = cursor.position();
+            if (pos >= suggestion->currentPosition()) {
+                suggestion->setCurrentPosition(pos);
+                if (suggestion->filterSuggestions(q)) {
+                    TextDocumentLayout::updateSuggestionFormats(
+                        m_suggestionBlock, m_document->fontSettings());
+                    return;
                 }
             }
         }
+    }
+    clearCurrentSuggestion();
+}
 
 void TextEditorWidgetPrivate::clearCurrentSuggestion()
 {

src/plugins/texteditor/textsuggestion.cpp

@@ -47,11 +47,11 @@ bool TextSuggestion::applyLine(TextEditorWidget *widget)
     return applyPart(Line, widget);
 }
 
-void TextSuggestion::reset()
+bool TextSuggestion::filterSuggestions(TextEditorWidget *widget)
 {
-    QTextCursor c = m_suggestion.position.toTextCursor(sourceDocument());
+    QTextCursor c = m_suggestion.range.begin.toTextCursor(sourceDocument());
     c.setPosition(currentPosition(), QTextCursor::KeepAnchor);
-    c.removeSelectedText();
+    return m_suggestion.text.startsWith(c.selectedText(), Qt::CaseInsensitive);
 }
 
 bool TextSuggestion::applyPart(Part part, TextEditorWidget *widget)
@@ -98,6 +98,38 @@ CyclicSuggestion::CyclicSuggestion(
     , m_currentSuggestion(currentSuggestion)
 {}
 
+bool operator==(const TextSuggestion::Data &lhs, const TextSuggestion::Data &rhs)
+{
+    return lhs.text == rhs.text && lhs.range == rhs.range && lhs.position == rhs.position;
+}
+
+bool CyclicSuggestion::filterSuggestions(TextEditorWidget *widget)
+{
+    QList<Data> newSuggestions;
+    int newIndex = -1;
+    int currentIndex = 0;
+    for (auto suggestion : m_suggestions) {
+        QTextCursor c = suggestion.range.begin.toTextCursor(sourceDocument());
+        c.setPosition(currentPosition(), QTextCursor::KeepAnchor);
+        if (suggestion.text.startsWith(c.selectedText())) {
+            newSuggestions.append(suggestion);
+            if (currentIndex == m_currentSuggestion)
+                newIndex = newSuggestions.size() - 1;
+        } else if (currentIndex == m_currentSuggestion) {
+            newIndex = 0;
+        }
+        ++currentIndex;
+    }
+    if (newSuggestions.isEmpty())
+        return false;
+
+    if (newSuggestions != m_suggestions) {
+        widget->insertSuggestion(
+            std::make_unique<CyclicSuggestion>(newSuggestions, sourceDocument(), newIndex));
+    }
+    return true;
+}
+
 class SuggestionToolTip : public QToolBar
 {
 public:
@@ -108,33 +140,41 @@ public:
         , m_currentSuggestion(std::max(0, std::min<int>(currentSuggestion, suggestions.size() - 1)))
         , m_editor(editor)
     {
-        auto prev = addAction(
-            Utils::Icons::PREV_TOOLBAR.icon(), Tr::tr("Select Previous Suggestion"));
-        prev->setEnabled(m_suggestions.size() > 1);
+        m_prev = addAction(Utils::Icons::PREV_TOOLBAR.icon(), Tr::tr("Select Previous Suggestion"));
         addWidget(m_numberLabel);
-        auto next
-            = addAction(Utils::Icons::NEXT_TOOLBAR.icon(), Tr::tr("Select Next Suggestion"));
-        next->setEnabled(m_suggestions.size() > 1);
+        m_next = addAction(Utils::Icons::NEXT_TOOLBAR.icon(), Tr::tr("Select Next Suggestion"));
 
         auto apply = addAction(Tr::tr("Apply (%1)").arg(QKeySequence(Qt::Key_Tab).toString()));
         auto applyWord = addAction(
             Tr::tr("Apply Word (%1)").arg(QKeySequence(QKeySequence::MoveToNextWord).toString()));
         auto applyLine = addAction(Tr::tr("Apply Line"));
 
-        connect(prev, &QAction::triggered, this, &SuggestionToolTip::selectPrevious);
-        connect(next, &QAction::triggered, this, &SuggestionToolTip::selectNext);
+        connect(m_prev, &QAction::triggered, this, &SuggestionToolTip::selectPrevious);
+        connect(m_next, &QAction::triggered, this, &SuggestionToolTip::selectNext);
         connect(apply, &QAction::triggered, this, &SuggestionToolTip::apply);
         connect(applyWord, &QAction::triggered, this, &SuggestionToolTip::applyWord);
         connect(applyLine, &QAction::triggered, this, &SuggestionToolTip::applyLine);
+        connect(editor->document(), &QTextDocument::contentsChange, this, &SuggestionToolTip::contentsChanged);
 
-        updateLabels();
+        updateSuggestionSelector();
     }
 
 private:
-    void updateLabels()
+    void contentsChanged()
+    {
+        if (auto *suggestion = dynamic_cast<CyclicSuggestion *>(m_editor->currentSuggestion())) {
+            m_suggestions = suggestion->suggestions();
+            m_currentSuggestion = suggestion->currentSuggestion();
+            updateSuggestionSelector();
+        }
+    }
+
+    void updateSuggestionSelector()
     {
         m_numberLabel->setText(
             Tr::tr("%1 of %2").arg(m_currentSuggestion + 1).arg(m_suggestions.count()));
+        m_prev->setEnabled(m_suggestions.size() > 1);
+        m_next->setEnabled(m_suggestions.size() > 1);
     }
 
     void selectPrevious()
@@ -155,9 +195,7 @@ private:
 
     void setCurrentSuggestion()
     {
-        updateLabels();
-        if (TextSuggestion *suggestion = m_editor->currentSuggestion())
-            suggestion->reset();
+        updateSuggestionSelector();
         m_editor->insertSuggestion(std::make_unique<CyclicSuggestion>(
             m_suggestions, m_editor->document(), m_currentSuggestion));
     }
@@ -190,6 +228,8 @@ private:
     }
 
     QLabel *m_numberLabel;
+    QAction *m_prev;
+    QAction *m_next;
     QList<TextSuggestion::Data> m_suggestions;
     int m_currentSuggestion = 0;
     TextEditorWidget *m_editor;

src/plugins/texteditor/textsuggestion.h

@@ -35,7 +35,7 @@ public:
     // Returns true if the suggestion was applied completely, false if it was only partially applied.
     virtual bool applyWord(TextEditorWidget *widget);
     virtual bool applyLine(TextEditorWidget *widget);
-    virtual void reset();
+    virtual bool filterSuggestions(TextEditorWidget *widget);
 
     int currentPosition() const { return m_currentPosition; }
     void setCurrentPosition(int position) { m_currentPosition = position; }
@@ -63,6 +63,8 @@ public:
     int currentSuggestion() const { return m_currentSuggestion; }
 
 private:
+    bool filterSuggestions(TextEditorWidget *widget) override;
+
     QList<Data> m_suggestions;
     int m_currentSuggestion = 0;
 };