Language widget for panel

data/css/default.css

@@ -59,4 +59,16 @@
 
 .wf-panel .command-output.icon-bottom label {
     padding-bottom: 5px;
+}
+
+.wf-panel .language {
+    min-width: 48px;
+}
+
+.wf-panel .language label {
+    background-color: #24283B;
+    padding: 5px;
+    margin: 5px;
+    border-radius: 3px; 
+    color: #41A6B5;
 }

meson.build

@@ -22,6 +22,8 @@ gtklayershell  = dependency('gtk-layer-shell-0', version: '>= 0.6', fallback: ['
 libpulse       = dependency('libpulse', required : get_option('pulse'))
 dbusmenu_gtk   = dependency('dbusmenu-gtk3-0.4')
 libgvc         = subproject('gvc', default_options: ['static=true'], required : get_option('pulse'))
+xkbregistry    = dependency('xkbregistry')
+json           = dependency('nlohmann_json')
 
 if get_option('wayland-logout') == true
   wayland_logout = subproject('wayland-logout')

src/panel/meson.build

@@ -2,6 +2,7 @@ widget_sources = ['widgets/battery.cpp',
                   'widgets/menu.cpp',
                   'widgets/clock.cpp',
                   'widgets/command-output.cpp',
+                  'widgets/language.cpp',
                   'widgets/launchers.cpp',
                   'widgets/network.cpp',
                   'widgets/spacing.cpp',
@@ -17,7 +18,7 @@ widget_sources = ['widgets/battery.cpp',
                   'widgets/tray/item.cpp',
                   'widgets/tray/host.cpp']
 
-deps = [gtkmm, wayland_client, libutil, wf_protos, wfconfig, gtklayershell, dbusmenu_gtk]
+deps = [gtkmm, wayland_client, libutil, wf_protos, wfconfig, gtklayershell, dbusmenu_gtk, xkbregistry]
 
 if libpulse.found()
   widget_sources += 'widgets/volume.cpp'

src/panel/panel.cpp

@@ -6,8 +6,8 @@
 #include <gdk/gdkwayland.h>
 #include <gtk-layer-shell.h>
 
-#include <stdio.h>
 #include <iostream>
+#include <memory>
 #include <sstream>
 
 #include <map>
@@ -16,8 +16,10 @@
 #include "panel.hpp"
 #include "../util/gtk-utils.hpp"
 
+#include "wf-ipc.hpp"
 #include "widgets/battery.hpp"
 #include "widgets/command-output.hpp"
+#include "widgets/language.hpp"
 #include "widgets/menu.hpp"
 #include "widgets/clock.hpp"
 #include "widgets/launchers.hpp"
@@ -36,6 +38,7 @@
 class WayfirePanel::impl
 {
     std::unique_ptr<WayfireAutohidingWindow> window;
+    WayfireIPC* ipc;
 
     Gtk::HBox content_box;
     Gtk::HBox left_box, center_box, right_box;
@@ -226,6 +229,11 @@ class WayfirePanel::impl
             return Widget(new WfCommandOutputButtons());
         }
 
+        if (name == "language")
+        {
+            return Widget(new WayfireLanguage(ipc));
+        }
+
         if (auto pixel = widget_with_value(name, "spacing"))
         {
             return Widget(new WayfireSpacing(*pixel));
@@ -313,7 +321,7 @@ class WayfirePanel::impl
     }
 
   public:
-    impl(WayfireOutput *output) : output(output)
+    impl(WayfireOutput *output, WayfireIPC *ipc) : ipc(ipc), output(output)
     {
         create_window();
     }
@@ -347,8 +355,9 @@ class WayfirePanel::impl
     }
 };
 
-WayfirePanel::WayfirePanel(WayfireOutput *output) : pimpl(new impl(output))
+WayfirePanel::WayfirePanel(WayfireOutput *output, WayfireIPC *ipc) : pimpl(new impl(output, ipc))
 {}
+
 wl_surface*WayfirePanel::get_wl_surface()
 {
     return pimpl->get_wl_surface();
@@ -437,7 +446,7 @@ void WayfirePanelApp::add_css_file(std::string file, int priority)
 void WayfirePanelApp::handle_new_output(WayfireOutput *output)
 {
     priv->panels[output] = std::unique_ptr<WayfirePanel>(
-        new WayfirePanel(output));
+        new WayfirePanel(output, ipc));
 }
 
 WayfirePanel*WayfirePanelApp::panel_for_wl_output(wl_output *output)

src/panel/panel.hpp

@@ -6,12 +6,13 @@
 #include <gtkmm/window.h>
 #include <gtkmm/cssprovider.h>
 
+#include "wf-ipc.hpp"
 #include "wf-shell-app.hpp"
 
 class WayfirePanel
 {
   public:
-    WayfirePanel(WayfireOutput *output);
+    WayfirePanel(WayfireOutput *output, WayfireIPC *ipc);
 
     wl_surface *get_wl_surface();
     Gtk::Window& get_window();

src/panel/widgets/language.cpp

@@ -0,0 +1,105 @@
+#include <cstddef>
+#include <cstdint>
+#include <glibmm.h>
+#include <map>
+#include <nlohmann/json_fwd.hpp>
+#include <string>
+#include <vector>
+#include <xkbcommon/xkbregistry.h>
+#include "language.hpp"
+#include "gtkmm/button.h"
+#include "sigc++/functors/mem_fun.h"
+
+void WayfireLanguage::init(Gtk::HBox *container) {
+    button.get_style_context()->add_class("language");
+    button.add(label);
+    button.get_style_context()->add_class("flat");
+    button.get_style_context()->remove_class("activated");
+    button.signal_clicked().connect_notify(sigc::mem_fun(this, &WayfireLanguage::next_layout));
+    button.show();
+    label.show();
+
+    ipc->subscribe(this, {"keyboard-modifier-state-changed"});
+    ipc->send("{\"method\":\"wayfire/get-keyboard-state\"}", [=](nlohmann::json data) {
+        set_available(data["possible-layouts"]);
+        set_current(data["layout-index"]);    
+    });
+
+    container->pack_start(button, false, false);
+}
+
+void WayfireLanguage::on_event(nlohmann::json data) {
+    if (data["event"] == "keyboard-modifier-state-changed") {
+        if (available_layouts.size() == 0) {
+            set_available(data["state"]["possible-layouts"]);
+        }
+
+        auto state_layout = data["state"]["layout-index"];
+        if (state_layout != current_layout) {
+            current_layout = state_layout;
+            set_current(state_layout);
+        }
+    }
+}
+
+bool WayfireLanguage::update_label() {
+    if (current_layout >= available_layouts.size()) {
+        return false;
+    }
+    label.set_text(available_layouts[current_layout].ID);
+    return true;
+}
+
+void WayfireLanguage::set_current(uint32_t index) {
+    current_layout = index;
+    update_label();
+}
+
+void WayfireLanguage::set_available(nlohmann::json layouts) {
+    std::vector<Layout> layouts_available;
+    std::map<std::string, uint32_t> names;
+
+    for(size_t i = 0; i < layouts.size(); i++) {
+        auto elem = layouts[i];
+        names[elem] = i;
+        layouts_available.push_back(Layout{
+            .Name = (std::string)elem,
+            .ID = "",
+        });
+    }
+
+    auto context = rxkb_context_new(RXKB_CONTEXT_NO_FLAGS);
+    rxkb_context_parse_default_ruleset(context);
+    auto rlayout = rxkb_layout_first(context);
+    for (; rlayout != NULL; rlayout = rxkb_layout_next(rlayout)) {
+        auto descr = rxkb_layout_get_description(rlayout);
+        auto name = names.find(descr);
+        if (name != names.end()) {
+            layouts_available[name->second].ID = rxkb_layout_get_brief(rlayout);
+        }
+    }
+
+    available_layouts = layouts_available;
+    update_label();
+}
+
+void WayfireLanguage::next_layout() {
+    uint32_t next = current_layout + 1;
+    if (next >= available_layouts.size())
+    {
+        next = 0;
+    }
+
+    nlohmann::json message;
+    message["method"] = "wayfire/set-keyboard-state";
+    message["data"] = nlohmann::json::object();
+    message["data"]["layout-index"] = next;
+    ipc->send(message.dump());
+}
+
+WayfireLanguage::WayfireLanguage(WayfireIPC *ipc): ipc(ipc)
+{}
+
+WayfireLanguage::~WayfireLanguage() {
+    ipc->unsubscribe(this);
+}

src/panel/widgets/language.hpp

@@ -0,0 +1,40 @@
+#ifndef WIDGETS_LANGUAGE_HPP
+#define WIDGETS_LANGUAGE_HPP
+
+#include "../widget.hpp"
+#include "gtkmm/button.h"
+#include "wf-ipc.hpp"
+#include <cstdint>
+#include <gtkmm/calendar.h>
+#include <gtkmm/label.h>
+#include <nlohmann/json_fwd.hpp>
+#include <string>
+#include <vector>
+
+struct Layout
+{
+  std::string Name;
+  std::string ID;
+};
+
+class WayfireLanguage : public WayfireWidget, public IIPCSubscriber
+{
+    Gtk::Label label;
+    Gtk::Button button;
+
+    WayfireIPC *ipc;
+    uint32_t current_layout;
+    std::vector<Layout> available_layouts;
+
+  public:
+    void init(Gtk::HBox *container) override;
+    void on_event(nlohmann::json data) override;
+    bool update_label();
+    void set_current(uint32_t index);
+    void set_available(nlohmann::json layouts);
+    void next_layout();
+    WayfireLanguage(WayfireIPC *ipc);
+    ~WayfireLanguage();
+};
+
+#endif /* end of include guard: WIDGETS_LANGUAGE_HPP */

src/util/meson.build

@@ -1,5 +1,5 @@
-util = static_library('util', ['gtk-utils.cpp', 'wf-shell-app.cpp', 'wf-autohide-window.cpp', 'wf-popover.cpp'],
-    dependencies: [wf_protos, wayland_client, gtkmm, wfconfig, libinotify, gtklayershell])
+util = static_library('util', ['gtk-utils.cpp', 'wf-shell-app.cpp', 'wf-autohide-window.cpp', 'wf-popover.cpp', 'wf-ipc.cpp'],
+    dependencies: [wf_protos, wayland_client, gtkmm, wfconfig, libinotify, gtklayershell, json])
 
 util_includes = include_directories('.')
 libutil = declare_dependency(