Add Plasma task group shortcuts

plasma-task-group-shortcuts/keyboardlayout.cpp

@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: MIT
+
+#include "keyboardlayout.h"
+
+#include <QDBusArgument>
+#include <QDBusInterface>
+#include <QDBusMetaType>
+#include <QDBusReply>
+#include <QDebug>
+
+#include <memory>
+
+#include <xkbcommon/xkbcommon.h>
+
+namespace KeyboardLayoutDbus
+{
+struct Layout
+{
+    QString name;
+    QString variant;
+    QString displayName;
+};
+
+using Layouts = QList<Layout>;
+
+QDBusArgument &operator<<(QDBusArgument &argument, const Layout &layout)
+{
+    argument.beginStructure();
+    argument << layout.name << layout.variant << layout.displayName;
+    argument.endStructure();
+    return argument;
+}
+
+const QDBusArgument &operator>>(const QDBusArgument &argument, Layout &layout)
+{
+    argument.beginStructure();
+    argument >> layout.name >> layout.variant >> layout.displayName;
+    argument.endStructure();
+    return argument;
+}
+}
+
+Q_DECLARE_METATYPE(KeyboardLayoutDbus::Layout)
+Q_DECLARE_METATYPE(KeyboardLayoutDbus::Layouts)
+
+namespace
+{
+KeyboardLayoutDbus::Layouts configuredLayouts()
+{
+    qDBusRegisterMetaType<KeyboardLayoutDbus::Layout>();
+    qDBusRegisterMetaType<KeyboardLayoutDbus::Layouts>();
+
+    QDBusInterface layouts(QStringLiteral("org.kde.KWin"), QStringLiteral("/Layouts"),
+                           QStringLiteral("org.kde.KeyboardLayouts"));
+    const QDBusReply<KeyboardLayoutDbus::Layouts> reply = layouts.call(QStringLiteral("getLayoutsList"));
+    if (!reply.isValid()) {
+        qWarning() << "Could not read KWin keyboard layouts:" << reply.error().message();
+        return {};
+    }
+    return reply.value();
+}
+}
+
+std::optional<Qt::Key> numberRowKey(QStringView layout, QStringView variant, int number, bool shifted)
+{
+    if (number < 1 || number > 9) {
+        return std::nullopt;
+    }
+
+    using Context = std::unique_ptr<xkb_context, decltype(&xkb_context_unref)>;
+    using Keymap = std::unique_ptr<xkb_keymap, decltype(&xkb_keymap_unref)>;
+    using State = std::unique_ptr<xkb_state, decltype(&xkb_state_unref)>;
+
+    const Context context(xkb_context_new(XKB_CONTEXT_NO_FLAGS), xkb_context_unref);
+    if (!context) {
+        return std::nullopt;
+    }
+
+    const QByteArray layoutName = layout.toLatin1();
+    const QByteArray variantName = variant.toLatin1();
+    const xkb_rule_names names{
+        .layout = layoutName.constData(),
+        .variant = variantName.isEmpty() ? nullptr : variantName.constData(),
+    };
+    const Keymap keymap(xkb_keymap_new_from_names(context.get(), &names, XKB_KEYMAP_COMPILE_NO_FLAGS),
+                        xkb_keymap_unref);
+    if (!keymap) {
+        return std::nullopt;
+    }
+
+    const State state(xkb_state_new(keymap.get()), xkb_state_unref);
+    if (!state) {
+        return std::nullopt;
+    }
+
+    if (shifted) {
+        const xkb_mod_index_t shift = xkb_keymap_mod_get_index(keymap.get(), XKB_MOD_NAME_SHIFT);
+        if (shift == XKB_MOD_INVALID) {
+            return std::nullopt;
+        }
+        xkb_state_update_mask(state.get(), xkb_mod_mask_t{1} << shift, 0, 0, 0, 0, 0);
+    }
+    const QByteArray keyName = QByteArrayLiteral("AE0") + QByteArray::number(number);
+    const xkb_keycode_t keycode = xkb_keymap_key_by_name(keymap.get(), keyName.constData());
+    if (keycode == XKB_KEYCODE_INVALID) {
+        return std::nullopt;
+    }
+    const uint32_t codePoint = xkb_keysym_to_utf32(xkb_state_key_get_one_sym(state.get(), keycode));
+    if (codePoint == 0) {
+        return std::nullopt;
+    }
+    return static_cast<Qt::Key>(codePoint);
+}
+
+QList<QKeySequence> numberRowShortcuts(int number)
+{
+    QList<QKeySequence> shortcuts;
+    for (const auto &layout : configuredLayouts()) {
+        for (const bool shifted : {false, true}) {
+            const auto key = numberRowKey(layout.name, layout.variant, number, shifted);
+            if (!key) {
+                qWarning() << "Could not map number-row key" << number << "for keyboard layout" << layout.name;
+                continue;
+            }
+
+            const QKeySequence sequence(Qt::META | *key);
+            if (!shortcuts.contains(sequence)) {
+                shortcuts.append(sequence);
+            }
+        }
+    }
+    return shortcuts;
+}