[Client] Settings: isolate the selected section when drilling down (#7488)

* [Client] Settings: isolate the selected section when drilling down

Show only the selected section's group box. Restore the overview on
page rows. Filter search results to the control's containing section.
Reset the scroll position on every change.

Reworked to stay in the enlarged modal instead of the settings tab.

* [Client] Settings: re-clicking an isolated section restores the overview

* [Settings] Keep section row selected when drilling down per review

* [Settings] Stop stealing nav selection mid-gesture per review

* [Settings] Sample nav selection pre-press so re-click detection works per review

* Don't flash the section on drill-down

* [Client] Settings: clear the section filter when selecting the page row per review

onTabClicked() returned early for the already-current page before switchPageContent() could call applySectionFilter(index, nullptr), so clicking the page row while a section was isolated moved the selection but left the page filtered. Only skip the restore when no section is isolated.

* [Settings] Select the search result's section in the sidebar per review

Reaching a setting through the search isolated its section and flashed the
widget, but left the navigation selection on the page row, so the sidebar
looked like it had only jumped to the section's page. Extract the section-row
selection shared with drill-down into selectSectionRow() and use it for search
results too, keeping the gesture/re-click behavior untouched.

---------

Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>

cockatrice/src/interface/widgets/dialogs/settings_view.cpp

@@ -37,6 +37,7 @@
 #include <QListView>
 #include <QMessageLogger>
 #include <QModelIndex>
+#include <QMouseEvent>
 #include <QObject>
 #include <QPalette>
 #include <QPixmap>
@@ -47,6 +48,7 @@
 #include <QScrollBar>
 #include <QSequentialAnimationGroup>
 #include <QShortcut>
+#include <QSignalBlocker>
 #include <QSize>
 #include <QSizePolicy>
 #include <QStackedLayout>
@@ -251,6 +253,13 @@ void SettingsView::setupNavTree()
     navTree->setStyleSheet(
         "QTreeWidget::item:selected { background: palette(highlight); color: palette(highlighted-text); }");
 
+    // Re-click detection has to sample the selection before the view handles the
+    // press: QAbstractItemView updates the current item (emitting
+    // currentItemChanged) and only then emits itemPressed, so itemPressed always
+    // sees the pressed item as "current" and cannot tell a re-click from a first
+    // click. The viewport event filter runs before QAbstractItemView::mousePressEvent.
+    navTree->viewport()->installEventFilter(this);
+
     // Groups of SettingsPage values, in navigation order
     static const QList<QList<SettingsPage>> groupedPages = {
         {GeneralPage, AppearancePage, UserInterfacePage},
@@ -301,6 +310,26 @@ void SettingsView::setupNavTree()
             onTabClicked(index);
         }
     });
+
+    connect(navTree, &QTreeWidget::itemClicked, this, [this](QTreeWidgetItem *item) {
+        const bool wasReClick = pressWasOnCurrentItem;
+        pressWasOnCurrentItem = false;
+        // A fresh click already navigated via currentItemChanged; only a press that
+        // started on the already-current item (captured by the viewport event filter
+        // before the view updated the selection) is a re-click. Re-clicking the
+        // isolated section restores the full page.
+        if (!wasReClick || item == nullptr || item != navTree->currentItem() || isolatedSection == nullptr ||
+            fromWidgetId(item->data(0, SectionWidgetRole).value<WidgetId>()) != isolatedSection) {
+            return;
+        }
+        bool ok = false;
+        const int index = item->data(0, Qt::UserRole).toInt(&ok);
+        if (ok) {
+            // setActiveTab, not onTabClicked: the page is already current and
+            // only setActiveTab clears the section filter
+            setActiveTab(index);
+        }
+    });
 }
 
 void SettingsView::buildSearchIndex()
@@ -328,7 +357,9 @@ void SettingsView::onTabClicked(int index)
 {
     if (searchActive) {
         switchToTabMode();
-    } else if (index == currentTabIndex) {
+    } else if (index == currentTabIndex && isolatedSection == nullptr) {
+        // Re-selecting the current page row is a no-op, but it must still clear
+        // an isolated section so the page's widgets come back.
         return;
     }
     setActiveTab(index);
@@ -340,15 +371,28 @@ void SettingsView::setActiveTab(int index)
         return;
     }
 
-    currentTabIndex = index;
-    pagesWidget->setCurrentIndex(index);
+    switchPageContent(index);
 
     // Selecting the item also expands a collapsed group; selecting the already
     // current item emits nothing, so the currentItemChanged handler cannot loop.
+    navTree->setCurrentItem(pageItems[index]);
+}
+
+void SettingsView::switchPageContent(int index)
+{
+    if (index < 0 || index >= pageItems.size() || !pageItems[index]) {
+        return;
+    }
+
+    currentTabIndex = index;
+    pagesWidget->setCurrentIndex(index);
+
+    // A page row always shows the full page; sections filter down from here
+    applySectionFilter(index, nullptr);
+
     if (QTreeWidgetItem *parent = pageItems[index]->parent()) {
         parent->setExpanded(true);
     }
-    navTree->setCurrentItem(pageItems[index]);
 }
 
 void SettingsView::flashWidget(QWidget *widget)
@@ -446,8 +490,19 @@ void SettingsView::navigateToSearchResult(const QModelIndex &index)
     switchToTabMode();
     setActiveTab(entry.pageIndex);
 
-    // Scroll to the widget, focus it, and flash to highlight it
+    // Isolate the control's section, then scroll to the widget, focus it, and flash it
     if (entry.widget) {
+        QWidget *section = nullptr;
+        for (const SettingsPageSection &candidate : pages[entry.pageIndex]->getSections()) {
+            if (candidate.sectionWidget == entry.widget ||
+                (candidate.sectionWidget && candidate.sectionWidget->isAncestorOf(entry.widget))) {
+                section = candidate.sectionWidget;
+                break;
+            }
+        }
+        applySectionFilter(entry.pageIndex, section);
+        // Keep the sidebar in sync with the deep link: highlight the setting's section row
+        selectSectionRow(entry.pageIndex, section);
         scrollToAndFlash(entry.widget);
         entry.widget->setFocus();
     }
@@ -459,15 +514,110 @@ void SettingsView::navigateToSection(int pageIndex, QWidget *sectionWidget)
         return;
     }
 
+    // Never steal the view's own selection mid-gesture: when this runs from
+    // currentItemChanged the section row is already current (mouse press or arrow key),
+    // and re-selecting the page row here is what made the selection visibly snap back
+    // to the parent on mouse release. selectSectionRow only acts on a known section
+    // that is not current yet, so it syncs programmatic callers without disturbing a gesture.
     if (currentTabIndex != pageIndex) {
         if (searchActive) {
             switchToTabMode();
         }
-        setActiveTab(pageIndex);
+        const QSignalBlocker blocker(navTree);
+        switchPageContent(pageIndex);
+    }
+    applySectionFilter(pageIndex, sectionWidget);
+
+    // Unknown widgets show the full page; known sections keep their row selected
+    selectSectionRow(pageIndex, sectionWidget);
+}
+
+/**
+ * @brief Selects the nav row for a section, expanding its page row
+ *
+ * A null or unknown section (a page whose sections are its own group boxes) leaves
+ * the current selection untouched, so callers can pass a lookup result directly.
+ *
+ * @param pageIndex SettingsPage owning the section
+ * @param sectionWidget Section's group box, or nullptr for no section
+ */
+void SettingsView::selectSectionRow(int pageIndex, QWidget *sectionWidget)
+{
+    if (!sectionWidget) {
+        return;
     }
 
-    // Focus stays in the navigation tree; only scroll and highlight the section
-    scrollToAndFlash(sectionWidget);
+    QTreeWidgetItem *sectionItem = findSectionItem(pageIndex, sectionWidget);
+    if (!sectionItem) {
+        return;
+    }
+
+    pageItems[pageIndex]->setExpanded(true);
+    if (navTree->currentItem() != sectionItem) {
+        const QSignalBlocker blocker(navTree);
+        navTree->setCurrentItem(sectionItem);
+    }
+}
+
+/**
+ * @brief Finds the nav row for a section widget
+ * @param pageIndex SettingsPage owning the section
+ * @param sectionWidget Section's group box
+ * @return The section's tree item, or nullptr when it has no row
+ */
+QTreeWidgetItem *SettingsView::findSectionItem(int pageIndex, QWidget *sectionWidget) const
+{
+    if (pageIndex < 0 || pageIndex >= pageItems.size() || !pageItems[pageIndex]) {
+        return nullptr;
+    }
+    for (int c = 0; c < pageItems[pageIndex]->childCount(); ++c) {
+        QTreeWidgetItem *child = pageItems[pageIndex]->child(c);
+        if (fromWidgetId(child->data(0, SectionWidgetRole).value<WidgetId>()) == sectionWidget) {
+            return child;
+        }
+    }
+    return nullptr;
+}
+
+/**
+ * @brief Shows only the given section of a page, hiding its siblings
+ *
+ * A null sectionWidget restores the full page. Unknown widgets fall back to
+ * the full page so a stale reference can never leave a blank page.
+ *
+ * @param pageIndex SettingsPage to filter
+ * @param sectionWidget Section's group box, or nullptr to show all sections
+ */
+void SettingsView::applySectionFilter(int pageIndex, QWidget *sectionWidget)
+{
+    if (pageIndex < 0 || pageIndex >= pages.size()) {
+        return;
+    }
+
+    const QList<SettingsPageSection> sections = pages[pageIndex]->getSections();
+
+    bool known = sectionWidget == nullptr;
+    for (const SettingsPageSection &section : sections) {
+        if (section.sectionWidget == sectionWidget) {
+            known = true;
+        }
+    }
+    if (!known) {
+        sectionWidget = nullptr;
+    }
+    isolatedSection = sectionWidget;
+
+    for (const SettingsPageSection &section : sections) {
+        if (section.sectionWidget) {
+            section.sectionWidget->setVisible(sectionWidget == nullptr || section.sectionWidget == sectionWidget);
+        }
+    }
+
+    if (auto *scrollArea = qobject_cast<QScrollArea *>(pagesWidget->widget(pageIndex))) {
+        if (QScrollBar *scrollBar = scrollArea->verticalScrollBar()) {
+            scrollBar->setValue(0);
+        }
+    }
 }
 
 void SettingsView::scrollToAndFlash(QWidget *target)
@@ -500,6 +650,17 @@ AbstractSettingsPage *SettingsView::page(SettingsPage which) const
 
 bool SettingsView::eventFilter(QObject *watched, QEvent *event)
 {
+    if (watched == navTree->viewport()) {
+        if (event->type() == QEvent::MouseButtonPress) {
+            auto *mouseEvent = static_cast<QMouseEvent *>(event);
+            // Left button only: context presses must never toggle the filter
+            QTreeWidgetItem *pressedItem = navTree->itemAt(mouseEvent->position().toPoint());
+            pressWasOnCurrentItem = mouseEvent->button() == Qt::LeftButton && pressedItem != nullptr &&
+                                    pressedItem == navTree->currentItem();
+        }
+        return false; // observation only: the view still handles the press
+    }
+
     if (watched == searchEdit && event->type() == QEvent::KeyPress) {
         auto *keyEvent = static_cast<QKeyEvent *>(event);
         if (keyEvent->key() == Qt::Key_Escape) {

cockatrice/src/interface/widgets/dialogs/settings_view.h

@@ -79,6 +79,8 @@ private:
     SettingsSearchDelegate *searchDelegate; ///< Delegate for search result rendering
     int currentTabIndex;                    ///< Currently active tab index
     bool searchActive;                      ///< Whether search mode is active
+    QWidget *isolatedSection = nullptr;     ///< Isolated section group box, or nullptr for full pages
+    bool pressWasOnCurrentItem = false;     ///< True when the mouse press started on the already-current item
 
     void setupUi();
     void setupNavTree();
@@ -88,6 +90,10 @@ private:
     void navigateToSearchResult(const QModelIndex &index);
     void navigateToSection(int pageIndex, QWidget *sectionWidget);
     void setActiveTab(int index);
+    void switchPageContent(int index);
+    void applySectionFilter(int pageIndex, QWidget *sectionWidget);
+    void selectSectionRow(int pageIndex, QWidget *sectionWidget);
+    QTreeWidgetItem *findSectionItem(int pageIndex, QWidget *sectionWidget) const;
     static void flashWidget(QWidget *widget);
     static void scrollToAndFlash(QWidget *target);
     static QStringList translatedPageNames();