From 8016ec256de0c3d2290d1446cda45a769a3c5284 Mon Sep 17 00:00:00 2001
From: Jake Stanger <mail@jstanger.dev>
Date: Sat, 27 Jan 2024 00:35:16 +0000
Subject: [PATCH 1/5] fix(tray): crash caused by excess updates

Some icons seem to absolutely spam updates in some circumstances. Increasing the channel size by 4x seems sufficient to prevent this.
---
 src/clients/system_tray.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/clients/system_tray.rs b/src/clients/system_tray.rs
index 60c8b129..aec5c0a6 100644
--- a/src/clients/system_tray.rs
+++ b/src/clients/system_tray.rs
@@ -25,7 +25,7 @@ impl TrayEventReceiver {
         let id = format!("ironbar-{}", Ironbar::unique_id());
 
         let (tx, rx) = mpsc::channel(16);
-        let (b_tx, b_rx) = broadcast::channel(16);
+        let (b_tx, b_rx) = broadcast::channel(64);
 
         let tray = StatusNotifierWatcher::new(rx).await?;
         let mut host = Box::pin(tray.create_notifier_host(&id)).await?;
@@ -48,7 +48,7 @@ impl TrayEventReceiver {
                             item,
                             menu,
                         } => {
-                            debug!("Adding item with address '{address}'");
+                            debug!("Adding/updating item with address '{address}'");
                             tray.insert(address, (item, menu));
                         }
                         NotifierItemMessage::Remove { address } => {

From b3a70ce8fa76b0ae8b06f423e7d5955c6d5d6920 Mon Sep 17 00:00:00 2001
From: Jake Stanger <mail@jstanger.dev>
Date: Sat, 27 Jan 2024 01:01:10 +0000
Subject: [PATCH 2/5] fix(tray): not handling checkbox items

---
 src/modules/tray.rs | 88 ++++++++++++++++++++++++++-------------------
 1 file changed, 52 insertions(+), 36 deletions(-)

diff --git a/src/modules/tray.rs b/src/modules/tray.rs
index 35a8b57c..63f248e1 100644
--- a/src/modules/tray.rs
+++ b/src/modules/tray.rs
@@ -9,7 +9,7 @@ use gtk::ffi::gtk_icon_theme_get_search_path;
 use gtk::gdk_pixbuf::{Colorspace, InterpType};
 use gtk::prelude::*;
 use gtk::{
-    gdk_pixbuf, IconLookupFlags, IconTheme, Image, Label, Menu, MenuBar, MenuItem,
+    gdk_pixbuf, CheckMenuItem, IconLookupFlags, IconTheme, Image, Label, Menu, MenuBar, MenuItem,
     SeparatorMenuItem,
 };
 use serde::Deserialize;
@@ -17,7 +17,7 @@ use std::collections::{HashMap, HashSet};
 use std::ffi::CStr;
 use std::os::raw::{c_char, c_int};
 use std::ptr;
-use system_tray::message::menu::{MenuItem as MenuItemInfo, MenuType};
+use system_tray::message::menu::{MenuItem as MenuItemInfo, MenuType, ToggleState, ToggleType};
 use system_tray::message::tray::StatusNotifierItem;
 use system_tray::message::{NotifierItemCommand, NotifierItemMessage};
 use tokio::sync::mpsc;
@@ -75,7 +75,7 @@ fn get_image_from_icon_name(item: &StatusNotifierItem, icon_theme: &IconTheme) -
 /// The pixmap is supplied in ARGB32 format,
 /// which has 8 bits per sample and a bit stride of `4*width`.
 fn get_image_from_pixmap(item: &StatusNotifierItem) -> Option<Image> {
-    const BITS_PER_SAMPLE: i32 = 8; //
+    const BITS_PER_SAMPLE: i32 = 8;
 
     let pixmap = item
         .icon_pixmap
@@ -109,46 +109,62 @@ fn get_menu_items(
     id: &str,
     path: &str,
 ) -> Vec<MenuItem> {
+    macro_rules! setup_menu_item {
+        ($builder:expr, $item_info:expr) => {{
+            if !$item_info.submenu.is_empty() {
+                let menu = Menu::new();
+                get_menu_items(&$item_info.submenu, &tx.clone(), id, path)
+                    .iter()
+                    .for_each(|item| menu.add(item));
+
+                $builder = $builder.submenu(&menu);
+            }
+
+            let item = $builder.build();
+
+            let info = $item_info.clone();
+            let id = id.to_string();
+            let path = path.to_string();
+
+            {
+                let tx = tx.clone();
+                item.connect_activate(move |_item| {
+                    try_send!(
+                        tx,
+                        NotifierItemCommand::MenuItemClicked {
+                            submenu_id: info.id,
+                            menu_path: path.clone(),
+                            notifier_address: id.clone(),
+                        }
+                    );
+                });
+            }
+
+            Box::new(item)
+        }};
+    }
+
     menu.iter()
         .map(|item_info| {
-            let item: Box<dyn AsRef<MenuItem>> = match item_info.menu_type {
-                MenuType::Separator => Box::new(SeparatorMenuItem::new()),
-                MenuType::Standard => {
+            let item: Box<dyn AsRef<MenuItem>> = match (item_info.menu_type, item_info.toggle_type)
+            {
+                (MenuType::Separator, _) => Box::new(SeparatorMenuItem::new()),
+                (MenuType::Standard, ToggleType::Checkmark) => {
+                    let mut builder = CheckMenuItem::builder()
+                        .label(item_info.label.as_str())
+                        .visible(item_info.visible)
+                        .sensitive(item_info.enabled)
+                        .active(item_info.toggle_state == ToggleState::On);
+
+                    setup_menu_item!(builder, item_info)
+                }
+                (MenuType::Standard, _) => {
                     let mut builder = MenuItem::builder()
                         .label(item_info.label.as_str())
                         .visible(item_info.visible)
                         .sensitive(item_info.enabled);
 
-                    if !item_info.submenu.is_empty() {
-                        let menu = Menu::new();
-                        get_menu_items(&item_info.submenu, &tx.clone(), id, path)
-                            .iter()
-                            .for_each(|item| menu.add(item));
-
-                        builder = builder.submenu(&menu);
-                    }
-
-                    let item = builder.build();
-
-                    let info = item_info.clone();
-                    let id = id.to_string();
-                    let path = path.to_string();
-
-                    {
-                        let tx = tx.clone();
-                        item.connect_activate(move |_item| {
-                            try_send!(
-                                tx,
-                                NotifierItemCommand::MenuItemClicked {
-                                    submenu_id: info.id,
-                                    menu_path: path.clone(),
-                                    notifier_address: id.clone(),
-                                }
-                            );
-                        });
-                    }
-
-                    Box::new(item)
+                    setup_menu_item!(builder, item_info)
                 }
             };
 

From cc39896181fd317440d94a054457ba01c649f0d7 Mon Sep 17 00:00:00 2001
From: Jake Stanger <mail@jstanger.dev>
Date: Sat, 27 Jan 2024 01:03:46 +0000
Subject: [PATCH 3/5] build: update `system-tray` crate

---
 Cargo.lock | 4 ++--
 Cargo.toml | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index b75a7fbe..d5bb9bb9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3002,9 +3002,9 @@ dependencies = [
 
 [[package]]
 name = "system-tray"
-version = "0.1.4"
+version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c8f7f19237d2149a8e4b56409c579b26a98748e3cfadba93762c4746c4c7ae2"
+checksum = "a456e3e6cbd396f1a3a91f8f74d1fdcf2bde85c97afe174442c367f4749fc09b"
 dependencies = [
  "anyhow",
  "byteorder",
diff --git a/Cargo.toml b/Cargo.toml
index 17972274..d3aa9fd0 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -125,7 +125,7 @@ mpris = { version = "2.0.1", optional = true }
 sysinfo = { version = "0.29.11", optional = true }
 
 # tray
-system-tray = { version = "0.1.4", optional = true }
+system-tray = { version = "0.1.5", optional = true }
 
 # upower
 upower_dbus = { version = "0.3.2", optional = true }

From 061663392e01503448fb44a064d172dbf10dc770 Mon Sep 17 00:00:00 2001
From: Jake Stanger <mail@jstanger.dev>
Date: Mon, 29 Jan 2024 23:30:25 +0000
Subject: [PATCH 4/5] fix: do not panic on full channels

---
 src/macros.rs | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/macros.rs b/src/macros.rs
index e71a5934..028fd196 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -62,8 +62,17 @@ macro_rules! glib_recv {
         glib::spawn_future_local(async move {
             // re-delcare in case ie `context.subscribe()` is passed directly
             let mut rx = $rx;
-            while let Ok($val) = rx.recv().await {
-                $expr
+            loop {
+                match rx.recv().await {
+                    Ok($val) => $expr,
+                    Err(tokio::sync::broadcast::error::RecvError::Lagged(count)) => {
+                        tracing::warn!("Channel lagged behind by {count}, this may result in unexpected or broken behaviour");
+                    }
+                    Err(err) => {
+                        tracing::error!("{err:?}");
+                        break;
+                    }
+                }
             }
         });
     }};

From 133632d1ad0778bb93e398e6d2bacf28c364f6c4 Mon Sep 17 00:00:00 2001
From: Jake Stanger <mail@jstanger.dev>
Date: Thu, 1 Feb 2024 21:43:20 +0000
Subject: [PATCH 5/5] fix(tray): vastly improve rendering performance

---
 src/modules/tray.rs           | 291 -------------------------------
 src/modules/tray/diff.rs      | 104 +++++++++++
 src/modules/tray/icon.rs      |  86 ++++++++++
 src/modules/tray/interface.rs | 314 ++++++++++++++++++++++++++++++++++
 src/modules/tray/mod.rs       | 146 ++++++++++++++++
 5 files changed, 650 insertions(+), 291 deletions(-)
 delete mode 100644 src/modules/tray.rs
 create mode 100644 src/modules/tray/diff.rs
 create mode 100644 src/modules/tray/icon.rs
 create mode 100644 src/modules/tray/interface.rs
 create mode 100644 src/modules/tray/mod.rs

diff --git a/src/modules/tray.rs b/src/modules/tray.rs
deleted file mode 100644
index 63f248e1..00000000
--- a/src/modules/tray.rs
+++ /dev/null
@@ -1,291 +0,0 @@
-use crate::clients::system_tray::TrayEventReceiver;
-use crate::config::CommonConfig;
-use crate::modules::{Module, ModuleInfo, ModuleParts, ModuleUpdateEvent, WidgetContext};
-use crate::{glib_recv, spawn, try_send};
-use color_eyre::Result;
-use glib::ffi::g_strfreev;
-use glib::translate::ToGlibPtr;
-use gtk::ffi::gtk_icon_theme_get_search_path;
-use gtk::gdk_pixbuf::{Colorspace, InterpType};
-use gtk::prelude::*;
-use gtk::{
-    gdk_pixbuf, CheckMenuItem, IconLookupFlags, IconTheme, Image, Label, Menu, MenuBar, MenuItem,
-    SeparatorMenuItem,
-};
-use serde::Deserialize;
-use std::collections::{HashMap, HashSet};
-use std::ffi::CStr;
-use std::os::raw::{c_char, c_int};
-use std::ptr;
-use system_tray::message::menu::{MenuItem as MenuItemInfo, MenuType, ToggleState, ToggleType};
-use system_tray::message::tray::StatusNotifierItem;
-use system_tray::message::{NotifierItemCommand, NotifierItemMessage};
-use tokio::sync::mpsc;
-use tokio::sync::mpsc::{Receiver, Sender};
-
-#[derive(Debug, Deserialize, Clone)]
-pub struct TrayModule {
-    #[serde(flatten)]
-    pub common: Option<CommonConfig>,
-}
-
-/// Gets the GTK icon theme search paths by calling the FFI function.
-/// Conveniently returns the result as a `HashSet`.
-fn get_icon_theme_search_paths(icon_theme: &IconTheme) -> HashSet<String> {
-    let mut gtk_paths: *mut *mut c_char = ptr::null_mut();
-    let mut n_elements: c_int = 0;
-    let mut paths = HashSet::new();
-    unsafe {
-        gtk_icon_theme_get_search_path(
-            icon_theme.to_glib_none().0,
-            &mut gtk_paths,
-            &mut n_elements,
-        );
-        // n_elements is never negative (that would be weird)
-        for i in 0..n_elements as usize {
-            let c_str = CStr::from_ptr(*gtk_paths.add(i));
-            if let Ok(str) = c_str.to_str() {
-                paths.insert(str.to_owned());
-            }
-        }
-
-        g_strfreev(gtk_paths);
-    }
-
-    paths
-}
-
-/// Attempts to get a GTK `Image` component
-/// for the status notifier item's icon.
-fn get_image_from_icon_name(item: &StatusNotifierItem, icon_theme: &IconTheme) -> Option<Image> {
-    if let Some(path) = item.icon_theme_path.as_ref() {
-        if !path.is_empty() && !get_icon_theme_search_paths(icon_theme).contains(path) {
-            icon_theme.append_search_path(path);
-        }
-    }
-
-    item.icon_name.as_ref().and_then(|icon_name| {
-        let icon_info = icon_theme.lookup_icon(icon_name, 16, IconLookupFlags::empty());
-        icon_info.map(|icon_info| Image::from_pixbuf(icon_info.load_icon().ok().as_ref()))
-    })
-}
-
-/// Attempts to get an image from the item pixmap.
-///
-/// The pixmap is supplied in ARGB32 format,
-/// which has 8 bits per sample and a bit stride of `4*width`.
-fn get_image_from_pixmap(item: &StatusNotifierItem) -> Option<Image> {
-    const BITS_PER_SAMPLE: i32 = 8;
-
-    let pixmap = item
-        .icon_pixmap
-        .as_ref()
-        .and_then(|pixmap| pixmap.first())?;
-
-    let bytes = glib::Bytes::from(&pixmap.pixels);
-    let row_stride = pixmap.width * 4; //
-
-    let pixbuf = gdk_pixbuf::Pixbuf::from_bytes(
-        &bytes,
-        Colorspace::Rgb,
-        true,
-        BITS_PER_SAMPLE,
-        pixmap.width,
-        pixmap.height,
-        row_stride,
-    );
-
-    let pixbuf = pixbuf
-        .scale_simple(16, 16, InterpType::Bilinear)
-        .unwrap_or(pixbuf);
-    Some(Image::from_pixbuf(Some(&pixbuf)))
-}
-
-/// Recursively gets GTK `MenuItem` components
-/// for the provided submenu array.
-fn get_menu_items(
-    menu: &[MenuItemInfo],
-    tx: &Sender<NotifierItemCommand>,
-    id: &str,
-    path: &str,
-) -> Vec<MenuItem> {
-    macro_rules! setup_menu_item {
-        ($builder:expr, $item_info:expr) => {{
-            if !$item_info.submenu.is_empty() {
-                let menu = Menu::new();
-                get_menu_items(&$item_info.submenu, &tx.clone(), id, path)
-                    .iter()
-                    .for_each(|item| menu.add(item));
-
-                $builder = $builder.submenu(&menu);
-            }
-
-            let item = $builder.build();
-
-            let info = $item_info.clone();
-            let id = id.to_string();
-            let path = path.to_string();
-
-            {
-                let tx = tx.clone();
-                item.connect_activate(move |_item| {
-                    try_send!(
-                        tx,
-                        NotifierItemCommand::MenuItemClicked {
-                            submenu_id: info.id,
-                            menu_path: path.clone(),
-                            notifier_address: id.clone(),
-                        }
-                    );
-                });
-            }
-
-            Box::new(item)
-        }};
-    }
-
-    menu.iter()
-        .map(|item_info| {
-            let item: Box<dyn AsRef<MenuItem>> = match (item_info.menu_type, item_info.toggle_type)
-            {
-                (MenuType::Separator, _) => Box::new(SeparatorMenuItem::new()),
-                (MenuType::Standard, ToggleType::Checkmark) => {
-                    let mut builder = CheckMenuItem::builder()
-                        .label(item_info.label.as_str())
-                        .visible(item_info.visible)
-                        .sensitive(item_info.enabled)
-                        .active(item_info.toggle_state == ToggleState::On);
-
-                    setup_menu_item!(builder, item_info)
-                }
-                (MenuType::Standard, _) => {
-                    let mut builder = MenuItem::builder()
-                        .label(item_info.label.as_str())
-                        .visible(item_info.visible)
-                        .sensitive(item_info.enabled);
-
-                    setup_menu_item!(builder, item_info)
-                }
-            };
-
-            (*item).as_ref().clone()
-        })
-        .collect()
-}
-
-impl Module<MenuBar> for TrayModule {
-    type SendMessage = NotifierItemMessage;
-    type ReceiveMessage = NotifierItemCommand;
-
-    fn name() -> &'static str {
-        "tray"
-    }
-
-    fn spawn_controller(
-        &self,
-        _info: &ModuleInfo,
-        context: &WidgetContext<Self::SendMessage, Self::ReceiveMessage>,
-        mut rx: Receiver<Self::ReceiveMessage>,
-    ) -> Result<()> {
-        let tx = context.tx.clone();
-
-        let client = context.client::<TrayEventReceiver>();
-
-        let (tray_tx, mut tray_rx) = client.subscribe();
-
-        // listen to tray updates
-        spawn(async move {
-            while let Ok(message) = tray_rx.recv().await {
-                tx.send(ModuleUpdateEvent::Update(message)).await?;
-            }
-
-            Ok::<(), mpsc::error::SendError<ModuleUpdateEvent<Self::SendMessage>>>(())
-        });
-
-        // send tray commands
-        spawn(async move {
-            while let Some(cmd) = rx.recv().await {
-                tray_tx.send(cmd).await?;
-            }
-
-            Ok::<(), mpsc::error::SendError<NotifierItemCommand>>(())
-        });
-
-        Ok(())
-    }
-
-    fn into_widget(
-        self,
-        context: WidgetContext<Self::SendMessage, Self::ReceiveMessage>,
-        info: &ModuleInfo,
-    ) -> Result<ModuleParts<MenuBar>> {
-        let container = MenuBar::new();
-
-        {
-            let container = container.clone();
-            let mut widgets = HashMap::new();
-            let icon_theme = info.icon_theme.clone();
-
-            // listen for UI updates
-            glib_recv!(context.subscribe(), update =>  {
-                match update {
-                    NotifierItemMessage::Update {
-                        item,
-                        address,
-                        menu,
-                    } => {
-                        let addr = &address;
-                        let menu_item = widgets.remove(address.as_str()).unwrap_or_else(|| {
-                            let menu_item = MenuItem::new();
-                            menu_item.style_context().add_class("item");
-
-                            get_image_from_icon_name(&item, &icon_theme)
-                                .or_else(|| get_image_from_pixmap(&item))
-                                .map_or_else(
-                                    || {
-                                        let label =
-                                            Label::new(Some(item.title.as_ref().unwrap_or(addr)));
-                                        menu_item.add(&label);
-                                    },
-                                    |image| {
-                                        image.set_widget_name(address.as_str());
-                                        menu_item.add(&image);
-                                    },
-                                );
-
-                            container.add(&menu_item);
-                            menu_item.show_all();
-                            menu_item
-                        });
-                        if let (Some(menu_opts), Some(menu_path)) = (menu, item.menu) {
-                            let submenus = menu_opts.submenus;
-                            if !submenus.is_empty() {
-                                let menu = Menu::new();
-                                get_menu_items(
-                                    &submenus,
-                                    &context.controller_tx.clone(),
-                                    &address,
-                                    &menu_path,
-                                )
-                                .iter()
-                                .for_each(|item| menu.add(item));
-                                menu_item.set_submenu(Some(&menu));
-                            }
-                        }
-                        widgets.insert(address, menu_item);
-                    }
-                    NotifierItemMessage::Remove { address } => {
-                        if let Some(widget) = widgets.get(&address) {
-                            container.remove(widget);
-                        }
-                    }
-                };
-            });
-        };
-
-        Ok(ModuleParts {
-            widget: container,
-            popup: None,
-        })
-    }
-}
diff --git a/src/modules/tray/diff.rs b/src/modules/tray/diff.rs
new file mode 100644
index 00000000..25e27b69
--- /dev/null
+++ b/src/modules/tray/diff.rs
@@ -0,0 +1,104 @@
+use system_tray::message::menu::{MenuItem as MenuItemInfo, ToggleState};
+
+/// Diff change type and associated info.
+#[derive(Debug, Clone)]
+pub enum Diff {
+    Add(MenuItemInfo),
+    Update(i32, MenuItemDiff),
+    Remove(i32),
+}
+
+/// Diff info to be applied to an existing menu item as an update.
+#[derive(Debug, Clone)]
+pub struct MenuItemDiff {
+    /// Text of the item,
+    pub label: Option<String>,
+    /// Whether the item can be activated or not.
+    pub enabled: Option<bool>,
+    /// True if the item is visible in the menu.
+    pub visible: Option<bool>,
+    /// Icon name of the item, following the freedesktop.org icon spec.
+    // pub icon_name: Option<Option<String>>,
+    /// Describe the current state of a "togglable" item. Can be one of:
+    ///   - Some(true): on
+    ///   - Some(false): off
+    ///   - None: indeterminate
+    pub toggle_state: Option<ToggleState>,
+    /// A submenu for this item, typically this would ve revealed to the user by hovering the current item
+    pub submenu: Vec<Diff>,
+}
+
+impl MenuItemDiff {
+    fn new(old: &MenuItemInfo, new: &MenuItemInfo) -> Self {
+        macro_rules! diff {
+            ($field:ident) => {
+                if old.$field == new.$field {
+                    None
+                } else {
+                    Some(new.$field)
+                }
+            };
+
+            (&$field:ident) => {
+                if &old.$field == &new.$field {
+                    None
+                } else {
+                    Some(new.$field.clone())
+                }
+            };
+        }
+
+        Self {
+            label: diff!(&label),
+            enabled: diff!(enabled),
+            visible: diff!(visible),
+            // icon_name: diff!(&icon_name),
+            toggle_state: diff!(toggle_state),
+            submenu: get_diffs(&old.submenu, &new.submenu),
+        }
+    }
+
+    /// Whether this diff contains any changes
+    fn has_diff(&self) -> bool {
+        self.label.is_some()
+            || self.enabled.is_some()
+            || self.visible.is_some()
+            // || self.icon_name.is_some()
+            || self.toggle_state.is_some()
+            || !self.submenu.is_empty()
+    }
+}
+
+/// Gets a diff set between old and new state.
+pub fn get_diffs(old: &[MenuItemInfo], new: &[MenuItemInfo]) -> Vec<Diff> {
+    let mut diffs = vec![];
+
+    for new_item in new {
+        let old_item = old.iter().find(|&item| item.id == new_item.id);
+
+        let diff = match old_item {
+            Some(old_item) => {
+                let item_diff = MenuItemDiff::new(old_item, new_item);
+                if item_diff.has_diff() {
+                    Some(Diff::Update(old_item.id, item_diff))
+                } else {
+                    None
+                }
+            }
+            None => Some(Diff::Add(new_item.clone())),
+        };
+
+        if let Some(diff) = diff {
+            diffs.push(diff);
+        }
+    }
+
+    for old_item in old {
+        let new_item = new.iter().find(|&item| item.id == old_item.id);
+        if new_item.is_none() {
+            diffs.push(Diff::Remove(old_item.id));
+        }
+    }
+
+    diffs
+}
diff --git a/src/modules/tray/icon.rs b/src/modules/tray/icon.rs
new file mode 100644
index 00000000..850137f6
--- /dev/null
+++ b/src/modules/tray/icon.rs
@@ -0,0 +1,86 @@
+use glib::ffi::g_strfreev;
+use glib::translate::ToGlibPtr;
+use gtk::ffi::gtk_icon_theme_get_search_path;
+use gtk::gdk_pixbuf::{Colorspace, InterpType};
+use gtk::prelude::IconThemeExt;
+use gtk::{gdk_pixbuf, IconLookupFlags, IconTheme, Image};
+use std::collections::HashSet;
+use std::ffi::CStr;
+use std::os::raw::{c_char, c_int};
+use std::ptr;
+use system_tray::message::tray::StatusNotifierItem;
+
+/// Gets the GTK icon theme search paths by calling the FFI function.
+/// Conveniently returns the result as a `HashSet`.
+fn get_icon_theme_search_paths(icon_theme: &IconTheme) -> HashSet<String> {
+    let mut gtk_paths: *mut *mut c_char = ptr::null_mut();
+    let mut n_elements: c_int = 0;
+    let mut paths = HashSet::new();
+    unsafe {
+        gtk_icon_theme_get_search_path(
+            icon_theme.to_glib_none().0,
+            &mut gtk_paths,
+            &mut n_elements,
+        );
+        // n_elements is never negative (that would be weird)
+        for i in 0..n_elements as usize {
+            let c_str = CStr::from_ptr(*gtk_paths.add(i));
+            if let Ok(str) = c_str.to_str() {
+                paths.insert(str.to_owned());
+            }
+        }
+
+        g_strfreev(gtk_paths);
+    }
+
+    paths
+}
+
+/// Attempts to get a GTK `Image` component
+/// for the status notifier item's icon.
+pub(crate) fn get_image_from_icon_name(
+    item: &StatusNotifierItem,
+    icon_theme: &IconTheme,
+) -> Option<Image> {
+    if let Some(path) = item.icon_theme_path.as_ref() {
+        if !path.is_empty() && !get_icon_theme_search_paths(icon_theme).contains(path) {
+            icon_theme.append_search_path(path);
+        }
+    }
+
+    item.icon_name.as_ref().and_then(|icon_name| {
+        let icon_info = icon_theme.lookup_icon(icon_name, 16, IconLookupFlags::empty());
+        icon_info.map(|icon_info| Image::from_pixbuf(icon_info.load_icon().ok().as_ref()))
+    })
+}
+
+/// Attempts to get an image from the item pixmap.
+///
+/// The pixmap is supplied in ARGB32 format,
+/// which has 8 bits per sample and a bit stride of `4*width`.
+pub(crate) fn get_image_from_pixmap(item: &StatusNotifierItem) -> Option<Image> {
+    const BITS_PER_SAMPLE: i32 = 8;
+
+    let pixmap = item
+        .icon_pixmap
+        .as_ref()
+        .and_then(|pixmap| pixmap.first())?;
+
+    let bytes = glib::Bytes::from(&pixmap.pixels);
+    let row_stride = pixmap.width * 4; //
+
+    let pixbuf = gdk_pixbuf::Pixbuf::from_bytes(
+        &bytes,
+        Colorspace::Rgb,
+        true,
+        BITS_PER_SAMPLE,
+        pixmap.width,
+        pixmap.height,
+        row_stride,
+    );
+
+    let pixbuf = pixbuf
+        .scale_simple(16, 16, InterpType::Bilinear)
+        .unwrap_or(pixbuf);
+    Some(Image::from_pixbuf(Some(&pixbuf)))
+}
diff --git a/src/modules/tray/interface.rs b/src/modules/tray/interface.rs
new file mode 100644
index 00000000..3b9d988d
--- /dev/null
+++ b/src/modules/tray/interface.rs
@@ -0,0 +1,314 @@
+use crate::modules::tray::diff::{Diff, MenuItemDiff};
+use crate::{spawn, try_send};
+use gtk::prelude::*;
+use gtk::{CheckMenuItem, Image, Label, Menu, MenuItem, SeparatorMenuItem};
+use std::collections::HashMap;
+use system_tray::message::menu::{MenuItem as MenuItemInfo, MenuType, ToggleState, ToggleType};
+use system_tray::message::NotifierItemCommand;
+use tokio::sync::mpsc;
+
+/// Calls a method on the underlying widget,
+/// passing in a single argument.
+///
+/// This is useful to avoid matching on
+/// `TrayMenuWidget` constantly.
+///
+/// # Example
+/// ```rust
+/// call!(container, add, my_widget)
+/// ```
+/// is the same as:
+/// ```
+/// match &my_widget {
+///     TrayMenuWidget::Separator(w) => {
+///         container.add(w);
+///     }
+///     TrayMenuWidget::Standard(w) => {
+///         container.add(w);
+///     }
+///     TrayMenuWidget::Checkbox(w) => {
+///         container.add(w);
+///     }
+/// }
+/// ```
+macro_rules! call {
+    ($parent:expr, $method:ident, $child:expr) => {
+        match &$child {
+            TrayMenuWidget::Separator(w) => {
+                $parent.$method(w);
+            }
+            TrayMenuWidget::Standard(w) => {
+                $parent.$method(w);
+            }
+            TrayMenuWidget::Checkbox(w) => {
+                $parent.$method(w);
+            }
+        }
+    };
+}
+
+/// Main tray icon to show on the bar
+pub(crate) struct TrayMenu {
+    pub(crate) widget: MenuItem,
+    menu_widget: Menu,
+    image_widget: Option<Image>,
+    label_widget: Option<Label>,
+
+    menu: HashMap<i32, TrayMenuItem>,
+    state: Vec<MenuItemInfo>,
+    icon_name: Option<String>,
+
+    tx: mpsc::Sender<i32>,
+}
+
+impl TrayMenu {
+    pub fn new(tx: mpsc::Sender<NotifierItemCommand>, address: String, path: String) -> Self {
+        let widget = MenuItem::new();
+        widget.style_context().add_class("item");
+
+        let (item_tx, mut item_rx) = mpsc::channel(8);
+
+        spawn(async move {
+            while let Some(id) = item_rx.recv().await {
+                try_send!(
+                    tx,
+                    NotifierItemCommand::MenuItemClicked {
+                        submenu_id: id,
+                        menu_path: path.clone(),
+                        notifier_address: address.clone(),
+                    }
+                );
+            }
+        });
+
+        let menu = Menu::new();
+        widget.set_submenu(Some(&menu));
+
+        Self {
+            widget,
+            menu_widget: menu,
+            image_widget: None,
+            label_widget: None,
+            state: vec![],
+            icon_name: None,
+            menu: HashMap::new(),
+            tx: item_tx,
+        }
+    }
+
+    /// Updates the label text, and shows it in favour of the image.
+    pub fn set_label(&mut self, text: &str) {
+        if let Some(image) = &self.image_widget {
+            image.hide();
+        }
+
+        self.label_widget
+            .get_or_insert_with(|| {
+                let label = Label::new(None);
+                self.widget.add(&label);
+                label.show();
+                label
+            })
+            .set_label(text);
+    }
+
+    /// Updates the image, and shows it in favour of the label.
+    pub fn set_image(&mut self, image: &Image) {
+        if let Some(label) = &self.label_widget {
+            label.hide();
+        }
+
+        if let Some(old) = self.image_widget.replace(image.clone()) {
+            self.widget.remove(&old);
+        }
+
+        self.widget.add(image);
+        image.show();
+    }
+
+    /// Applies a diff set to the submenu.
+    pub fn apply_diffs(&mut self, diffs: Vec<Diff>) {
+        for diff in diffs {
+            match diff {
+                Diff::Add(info) => {
+                    let item = TrayMenuItem::new(&info, self.tx.clone());
+                    call!(self.menu_widget, add, item.widget);
+                    self.menu.insert(item.id, item);
+                }
+                Diff::Update(id, info) => {
+                    if let Some(item) = self.menu.get_mut(&id) {
+                        item.apply_diff(info);
+                    }
+                }
+                Diff::Remove(id) => {
+                    if let Some(item) = self.menu.remove(&id) {
+                        call!(self.menu_widget, remove, item.widget);
+                    }
+                }
+            }
+        }
+    }
+
+    pub fn label_widget(&self) -> Option<&Label> {
+        self.label_widget.as_ref()
+    }
+
+    pub fn state(&self) -> &[MenuItemInfo] {
+        &self.state
+    }
+
+    pub fn set_state(&mut self, state: Vec<MenuItemInfo>) {
+        self.state = state;
+    }
+
+    pub fn icon_name(&self) -> Option<&String> {
+        self.icon_name.as_ref()
+    }
+
+    pub fn set_icon_name(&mut self, icon_name: Option<String>) {
+        self.icon_name = icon_name;
+    }
+}
+
+#[derive(Debug)]
+struct TrayMenuItem {
+    id: i32,
+    widget: TrayMenuWidget,
+    menu_widget: Menu,
+    submenu: HashMap<i32, TrayMenuItem>,
+    tx: mpsc::Sender<i32>,
+}
+
+#[derive(Debug)]
+enum TrayMenuWidget {
+    Separator(SeparatorMenuItem),
+    Standard(MenuItem),
+    Checkbox(CheckMenuItem),
+}
+
+impl TrayMenuItem {
+    fn new(info: &MenuItemInfo, tx: mpsc::Sender<i32>) -> Self {
+        let menu = Menu::new();
+
+        let widget = match (info.menu_type, info.toggle_type) {
+            (MenuType::Separator, _) => TrayMenuWidget::Separator(SeparatorMenuItem::new()),
+            (MenuType::Standard, ToggleType::Checkmark) => {
+                let widget = CheckMenuItem::builder()
+                    .label(info.label.as_str())
+                    .visible(info.visible)
+                    .sensitive(info.enabled)
+                    .active(info.toggle_state == ToggleState::On)
+                    .build();
+
+                {
+                    let tx = tx.clone();
+                    let id = info.id;
+
+                    widget.connect_activate(move |_item| {
+                        try_send!(tx, id);
+                    });
+                }
+
+                TrayMenuWidget::Checkbox(widget)
+            }
+            (MenuType::Standard, _) => {
+                let builder = MenuItem::builder()
+                    .label(&info.label)
+                    .visible(info.visible)
+                    .sensitive(info.enabled);
+
+                let widget = builder.build();
+
+                {
+                    let tx = tx.clone();
+                    let id = info.id;
+
+                    widget.connect_activate(move |_item| {
+                        try_send!(tx, id);
+                    });
+                }
+
+                TrayMenuWidget::Standard(widget)
+            }
+        };
+
+        Self {
+            id: info.id,
+            widget,
+            menu_widget: menu,
+            submenu: HashMap::new(),
+            tx,
+        }
+    }
+
+    /// Applies a diff to this submenu item.
+    ///
+    /// This is called recursively,
+    /// applying the submenu diffs to any further submenu items.
+    fn apply_diff(&mut self, diff: MenuItemDiff) {
+        if let Some(label) = diff.label {
+            match &self.widget {
+                TrayMenuWidget::Separator(widget) => widget.set_label(&label),
+                TrayMenuWidget::Standard(widget) => widget.set_label(&label),
+                TrayMenuWidget::Checkbox(widget) => widget.set_label(&label),
+            }
+        }
+
+        // TODO: Image support
+        // if let Some(icon_name) = diff.icon_name {
+        //
+        // }
+
+        if let Some(enabled) = diff.enabled {
+            match &self.widget {
+                TrayMenuWidget::Separator(widget) => widget.set_sensitive(enabled),
+                TrayMenuWidget::Standard(widget) => widget.set_sensitive(enabled),
+                TrayMenuWidget::Checkbox(widget) => widget.set_sensitive(enabled),
+            }
+        }
+
+        if let Some(visible) = diff.visible {
+            match &self.widget {
+                TrayMenuWidget::Separator(widget) => widget.set_visible(visible),
+                TrayMenuWidget::Standard(widget) => widget.set_visible(visible),
+                TrayMenuWidget::Checkbox(widget) => widget.set_visible(visible),
+            }
+        }
+
+        if let Some(toggle_state) = diff.toggle_state {
+            if let TrayMenuWidget::Checkbox(widget) = &self.widget {
+                widget.set_active(toggle_state == ToggleState::On);
+            }
+        }
+
+        for sub_diff in diff.submenu {
+            match sub_diff {
+                Diff::Add(info) => {
+                    let menu_item = TrayMenuItem::new(&info, self.tx.clone());
+                    call!(self.menu_widget, add, menu_item.widget);
+
+                    if let TrayMenuWidget::Standard(widget) = &self.widget {
+                        widget.set_submenu(Some(&self.menu_widget));
+                    }
+
+                    self.submenu.insert(menu_item.id, menu_item);
+                }
+                Diff::Update(id, diff) => {
+                    if let Some(sub) = self.submenu.get_mut(&id) {
+                        sub.apply_diff(diff);
+                    }
+                }
+                Diff::Remove(id) => {
+                    if let Some(sub) = self.submenu.remove(&id) {
+                        call!(self.menu_widget, remove, sub.widget);
+                    }
+                    if let TrayMenuWidget::Standard(widget) = &self.widget {
+                        if self.submenu.is_empty() {
+                            widget.set_submenu(None::<&Menu>);
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
diff --git a/src/modules/tray/mod.rs b/src/modules/tray/mod.rs
new file mode 100644
index 00000000..b2830a88
--- /dev/null
+++ b/src/modules/tray/mod.rs
@@ -0,0 +1,146 @@
+mod diff;
+mod icon;
+mod interface;
+
+use crate::clients::system_tray::TrayEventReceiver;
+use crate::config::CommonConfig;
+use crate::modules::tray::diff::get_diffs;
+use crate::modules::{Module, ModuleInfo, ModuleParts, ModuleUpdateEvent, WidgetContext};
+use crate::{glib_recv, spawn};
+use color_eyre::Result;
+use gtk::prelude::*;
+use gtk::{IconTheme, MenuBar};
+use interface::TrayMenu;
+use serde::Deserialize;
+use std::collections::HashMap;
+use system_tray::message::{NotifierItemCommand, NotifierItemMessage};
+use tokio::sync::mpsc;
+
+#[derive(Debug, Deserialize, Clone)]
+pub struct TrayModule {
+    #[serde(flatten)]
+    pub common: Option<CommonConfig>,
+}
+
+impl Module<MenuBar> for TrayModule {
+    type SendMessage = NotifierItemMessage;
+    type ReceiveMessage = NotifierItemCommand;
+
+    fn name() -> &'static str {
+        "tray"
+    }
+
+    fn spawn_controller(
+        &self,
+        _info: &ModuleInfo,
+        context: &WidgetContext<Self::SendMessage, Self::ReceiveMessage>,
+        mut rx: mpsc::Receiver<Self::ReceiveMessage>,
+    ) -> Result<()> {
+        let tx = context.tx.clone();
+
+        let client = context.client::<TrayEventReceiver>();
+
+        let (tray_tx, mut tray_rx) = client.subscribe();
+
+        // listen to tray updates
+        spawn(async move {
+            while let Ok(message) = tray_rx.recv().await {
+                tx.send(ModuleUpdateEvent::Update(message)).await?;
+            }
+
+            Ok::<(), mpsc::error::SendError<ModuleUpdateEvent<Self::SendMessage>>>(())
+        });
+
+        // send tray commands
+        spawn(async move {
+            while let Some(cmd) = rx.recv().await {
+                tray_tx.send(cmd).await?;
+            }
+
+            Ok::<(), mpsc::error::SendError<NotifierItemCommand>>(())
+        });
+
+        Ok(())
+    }
+
+    fn into_widget(
+        self,
+        context: WidgetContext<Self::SendMessage, Self::ReceiveMessage>,
+        info: &ModuleInfo,
+    ) -> Result<ModuleParts<MenuBar>> {
+        let container = MenuBar::new();
+
+        {
+            let container = container.clone();
+            let mut menus = HashMap::new();
+            let icon_theme = info.icon_theme.clone();
+
+            // listen for UI updates
+            glib_recv!(context.subscribe(), update =>
+                on_update(update, &container, &mut menus, &icon_theme, &context.controller_tx)
+            );
+        };
+
+        Ok(ModuleParts {
+            widget: container,
+            popup: None,
+        })
+    }
+}
+
+/// Handles UI updates as callback,
+/// getting the diff since the previous update and applying it to the menu.
+fn on_update(
+    update: NotifierItemMessage,
+    container: &MenuBar,
+    menus: &mut HashMap<Box<str>, TrayMenu>,
+    icon_theme: &IconTheme,
+    tx: &mpsc::Sender<NotifierItemCommand>,
+) {
+    match update {
+        NotifierItemMessage::Update {
+            item,
+            address,
+            menu,
+        } => {
+            if let (Some(menu_opts), Some(menu_path)) = (menu, &item.menu) {
+                let submenus = menu_opts.submenus;
+
+                let mut menu_item = menus.remove(address.as_str()).unwrap_or_else(|| {
+                    let item = TrayMenu::new(tx.clone(), address.clone(), menu_path.to_string());
+                    container.add(&item.widget);
+
+                    item
+                });
+
+                let label = item.title.as_ref().unwrap_or(&address);
+                if let Some(label_widget) = menu_item.label_widget() {
+                    label_widget.set_label(label);
+                }
+
+                if item.icon_name.as_ref() != menu_item.icon_name() {
+                    match icon::get_image_from_icon_name(&item, icon_theme)
+                        .or_else(|| icon::get_image_from_pixmap(&item))
+                    {
+                        Some(image) => menu_item.set_image(&image),
+                        None => menu_item.set_label(label),
+                    };
+                }
+
+                let diffs = get_diffs(menu_item.state(), &submenus);
+                menu_item.apply_diffs(diffs);
+                menu_item.widget.show();
+
+                menu_item.set_state(submenus);
+                menu_item.set_icon_name(item.icon_name);
+
+                menus.insert(address.into(), menu_item);
+            }
+        }
+        NotifierItemMessage::Remove { address } => {
+            if let Some(menu) = menus.get(address.as_str()) {
+                container.remove(&menu.widget);
+            }
+        }
+    };
+}