feat: Add a split view for code document

The right view shows the TreeSitter tree, like in the inspector view.

Related-to KDAB#62

src/gui/CMakeLists.txt

@@ -14,6 +14,8 @@ set(PROJECT_SOURCES
     apiexecutorwidget.h
     apiexecutorwidget.cpp
     apiexecutorwidget.ui
+    codeview.cpp
+    codeview.h
     documentpalette.h
     documentpalette.cpp
     fileselector.h

src/gui/codeview.cpp

@@ -0,0 +1,138 @@
+/*
+  This file is part of Knut.
+
+  SPDX-FileCopyrightText: 2024 Klarälvdalens Datakonsult AB, a KDAB Group company <info@kdab.com>
+
+  SPDX-License-Identifier: GPL-3.0-only
+
+  Contact KDAB at <info@kdab.com> for commercial licensing options.
+*/
+
+#include "codeview.h"
+#include "core/logger.h"
+#include "core/textdocument.h"
+#include "guisettings.h"
+#include "treesitter/languages.h"
+#include "treesitter/predicates.h"
+#include "treesittertreemodel.h"
+
+#include <QCheckBox>
+#include <QPlainTextEdit>
+#include <QSplitter>
+#include <QTreeView>
+#include <QVBoxLayout>
+
+namespace Gui {
+
+CodeView::CodeView(QWidget *parent)
+    : TextView(parent)
+    , m_parser(nullptr)
+{
+    auto *action = new QAction(tr("Show TreeSitter Explorer"));
+    action->setCheckable(true);
+    action->setChecked(false);
+    GuiSettings::setIcon(action, ":/gui/file-tree.png");
+    connect(action, &QAction::triggered, this, &CodeView::toggleTreeView);
+    addAction(action);
+}
+
+void CodeView::setDocument(Core::TextDocument *document)
+{
+    TextView::setDocument(document);
+
+    m_treeView = new QTreeView(this);
+    m_showUnnamed = new QCheckBox(tr("Show unnamed nodes"), this);
+
+    auto *splitter = new QSplitter(Qt::Horizontal, this);
+    splitter->addWidget(document->textEdit());
+    splitter->setCollapsible(0, false);
+
+    QWidget *rightWidget = new QWidget;
+    QVBoxLayout *vbox = new QVBoxLayout(rightWidget);
+    vbox->setContentsMargins({});
+    vbox->addWidget(m_treeView);
+    vbox->addWidget(m_showUnnamed);
+    splitter->addWidget(rightWidget);
+
+    layout()->addWidget(splitter);
+
+    // By default, the treesitter view is not visible
+    rightWidget->setVisible(false);
+}
+
+void CodeView::toggleTreeView()
+{
+    Q_ASSERT(m_treeView && document());
+    initializeCodeModel();
+    m_treeView->parentWidget()->setVisible(!m_treeView->isVisible());
+}
+
+void CodeView::toggleUnnamedNodes()
+{
+    // technically the text didn't change, but this will force
+    // a complete re-parse and re-build of the entire tree.
+    changeText();
+}
+
+void CodeView::initializeCodeModel()
+{
+    if (m_treemodel)
+        return;
+
+    m_treemodel = new TreeSitterTreeModel(this);
+    m_treeView->setModel(m_treemodel);
+    m_parser = treesitter::Parser::getLanguage(document()->type());
+    connect(document(), &Core::TextDocument::textChanged, this, &CodeView::changeText);
+    connect(document(), &Core::TextDocument::positionChanged, this, &CodeView::changeCursor);
+    connect(m_treeView->selectionModel(), &QItemSelectionModel::currentChanged, this, &CodeView::changeTreeSelection);
+    connect(m_showUnnamed, &QCheckBox::toggled, this, &CodeView::toggleUnnamedNodes);
+
+    changeCursor();
+    changeText();
+}
+
+void CodeView::changeText()
+{
+    QString text;
+    {
+        Core::LoggerDisabler disableLogging;
+        text = document()->text();
+    }
+    auto tree = m_parser.parseString(text);
+    if (tree.has_value()) {
+        m_treemodel->setTree(std::move(tree.value()), makePredicates(), m_showUnnamed->isChecked());
+        m_treeView->expandAll();
+        for (int i = 0; i < 2; i++) {
+            m_treeView->resizeColumnToContents(i);
+        }
+    }
+}
+
+void CodeView::changeCursor()
+{
+    int position;
+    {
+        Core::LoggerDisabler disableLogging;
+        position = document()->position();
+    }
+    m_treemodel->setCursorPosition(position);
+}
+
+void CodeView::changeTreeSelection(const QModelIndex &current)
+{
+    const auto node = m_treemodel->tsNode(current);
+    if (node.has_value()) {
+        Core::LoggerDisabler disableLogging;
+        document()->selectRegion(node->startPosition(), node->endPosition());
+    }
+}
+
+std::unique_ptr<treesitter::Predicates> CodeView::makePredicates()
+{
+    Q_ASSERT(document());
+    // No need to always log the call to TextDocument::text
+    Core::LoggerDisabler disabler;
+    return std::make_unique<treesitter::Predicates>(document()->text());
+}
+
+} // namespace Gui

src/gui/codeview.h

@@ -0,0 +1,52 @@
+/*
+  This file is part of Knut.
+
+  SPDX-FileCopyrightText: 2024 Klarälvdalens Datakonsult AB, a KDAB Group company <info@kdab.com>
+
+  SPDX-License-Identifier: GPL-3.0-only
+
+  Contact KDAB at <info@kdab.com> for commercial licensing options.
+*/
+
+#pragma once
+
+#include "textview.h"
+#include "treesitter/parser.h"
+
+class QTreeView;
+class QCheckBox;
+
+namespace treesitter {
+class Predicates;
+}
+
+namespace Gui {
+
+class TreeSitterTreeModel;
+
+class CodeView : public TextView
+{
+    Q_OBJECT
+
+public:
+    explicit CodeView(QWidget *parent = nullptr);
+
+    void setDocument(Core::TextDocument *document) override;
+
+private:
+    void toggleTreeView();
+    void toggleUnnamedNodes();
+
+    void initializeCodeModel();
+    void changeText();
+    void changeCursor();
+    void changeTreeSelection(const QModelIndex &current);
+    std::unique_ptr<treesitter::Predicates> makePredicates();
+
+    QTreeView *m_treeView = nullptr;
+    QCheckBox *m_showUnnamed = nullptr;
+    treesitter::Parser m_parser;
+    TreeSitterTreeModel *m_treemodel = nullptr;
+};
+
+} // namespace Gui

src/gui/gui.qrc

@@ -24,6 +24,7 @@
         <file>gui/magnify-minus.png</file>
         <file>gui/magnify-plus.png</file>
         <file>gui/lightbulb.png</file>
+        <file>gui/file-tree.png</file>
     </qresource>
     <qresource prefix="/org.kde.syntax-highlighting/syntax-addons">
         <file alias="rc.xml">gui/rc.xml</file>

src/gui/knutstyle.cpp

@@ -82,6 +82,8 @@ int KnutStyle::pixelMetric(PixelMetric metric, const QStyleOption *option, const
         return 1;
     case PM_TabBarTabVSpace:
         return 10;
+    case PM_SplitterWidth:
+        return 1;
     default:
         break;
     }

src/gui/mainwindow.cpp

@@ -9,6 +9,7 @@
 */
 
 #include "mainwindow.h"
+#include "codeview.h"
 #include "core/codedocument.h"
 #include "core/cppdocument.h"
 #include "core/document.h"
@@ -717,13 +718,19 @@ static QWidget *widgetForDocument(Core::Document *document)
         tsView->setTsDocument(qobject_cast<Core::QtTsDocument *>(document));
         return tsView;
     }
-    case Core::Document::Type::Json:
     case Core::Document::Type::Cpp:
+    case Core::Document::Type::Json:
     case Core::Document::Type::Text:
     default: {
-        auto textView = new TextView();
-        textView->setDocument(qobject_cast<Core::TextDocument *>(document));
-        return textView;
+        if (auto codeDocument = qobject_cast<Core::CodeDocument *>(document)) {
+            auto codeView = new CodeView();
+            codeView->setDocument(codeDocument);
+            return codeView;
+        } else {
+            auto textView = new TextView();
+            textView->setDocument(qobject_cast<Core::TextDocument *>(document));
+            return textView;
+        }
     }
     }
     Q_UNREACHABLE();