feat(bar): add cpu widget

This commit adds a CPU widget, following the patterns of the Memory
widget.

komorebi-bar/src/cpu.rs

@@ -0,0 +1,107 @@
+use crate::widget::BarWidget;
+use crate::WIDGET_SPACING;
+use eframe::egui::text::LayoutJob;
+use eframe::egui::Context;
+use eframe::egui::FontId;
+use eframe::egui::Label;
+use eframe::egui::Sense;
+use eframe::egui::TextFormat;
+use eframe::egui::TextStyle;
+use eframe::egui::Ui;
+use schemars::JsonSchema;
+use serde::Deserialize;
+use serde::Serialize;
+use std::process::Command;
+use std::time::Duration;
+use std::time::Instant;
+use sysinfo::RefreshKind;
+use sysinfo::System;
+
+#[derive(Copy, Clone, Debug, Serialize, Deserialize, JsonSchema)]
+pub struct CpuConfig {
+    /// Enable the Cpu widget
+    pub enable: bool,
+    /// Data refresh interval (default: 10 seconds)
+    pub data_refresh_interval: Option<u64>,
+}
+
+impl From<CpuConfig> for Cpu {
+    fn from(value: CpuConfig) -> Self {
+        let mut system =
+            System::new_with_specifics(RefreshKind::default().without_memory().without_processes());
+
+        system.refresh_cpu_usage();
+
+        Self {
+            enable: value.enable,
+            system,
+            data_refresh_interval: value.data_refresh_interval.unwrap_or(10),
+            last_updated: Instant::now(),
+        }
+    }
+}
+
+pub struct Cpu {
+    pub enable: bool,
+    system: System,
+    data_refresh_interval: u64,
+    last_updated: Instant,
+}
+
+impl Cpu {
+    fn output(&mut self) -> String {
+        let now = Instant::now();
+        if now.duration_since(self.last_updated) > Duration::from_secs(self.data_refresh_interval) {
+            self.system.refresh_cpu_usage();
+            self.last_updated = now;
+        }
+
+        let used = self.system.global_cpu_usage();
+        format!("CPU: {:.0}%", used)
+    }
+}
+
+impl BarWidget for Cpu {
+    fn render(&mut self, ctx: &Context, ui: &mut Ui) {
+        if self.enable {
+            let output = self.output();
+            if !output.is_empty() {
+                let font_id = ctx
+                    .style()
+                    .text_styles
+                    .get(&TextStyle::Body)
+                    .cloned()
+                    .unwrap_or_else(FontId::default);
+
+                let mut layout_job = LayoutJob::simple(
+                    egui_phosphor::regular::CIRCUITRY.to_string(),
+                    font_id.clone(),
+                    ctx.style().visuals.selection.stroke.color,
+                    100.0,
+                );
+
+                layout_job.append(
+                    &output,
+                    10.0,
+                    TextFormat::simple(font_id, ctx.style().visuals.text_color()),
+                );
+
+                if ui
+                    .add(
+                        Label::new(layout_job)
+                            .selectable(false)
+                            .sense(Sense::click()),
+                    )
+                    .clicked()
+                {
+                    if let Err(error) = Command::new("cmd.exe").args(["/C", "taskmgr.exe"]).spawn()
+                    {
+                        eprintln!("{}", error)
+                    }
+                }
+            }
+
+            ui.add_space(WIDGET_SPACING);
+        }
+    }
+}

komorebi-bar/src/main.rs

@@ -1,4 +1,5 @@
 mod bar;
+mod cpu;
 mod battery;
 mod config;
 mod date;

komorebi-bar/src/widget.rs

@@ -1,5 +1,7 @@
 use crate::battery::Battery;
 use crate::battery::BatteryConfig;
+use crate::cpu::Cpu;
+use crate::cpu::CpuConfig;
 use crate::date::Date;
 use crate::date::DateConfig;
 use crate::komorebi::Komorebi;
@@ -27,6 +29,7 @@ pub trait BarWidget {
 #[derive(Clone, Debug, Serialize, Deserialize, JsonSchema)]
 pub enum WidgetConfig {
     Battery(BatteryConfig),
+    Cpu(CpuConfig),
     Date(DateConfig),
     Komorebi(KomorebiConfig),
     Media(MediaConfig),
@@ -40,6 +43,7 @@ impl WidgetConfig {
     pub fn as_boxed_bar_widget(&self) -> Box<dyn BarWidget> {
         match self {
             WidgetConfig::Battery(config) => Box::new(Battery::from(*config)),
+            WidgetConfig::Cpu(config) => Box::new(Cpu::from(*config)),
             WidgetConfig::Date(config) => Box::new(Date::from(config.clone())),
             WidgetConfig::Komorebi(config) => Box::new(Komorebi::from(config)),
             WidgetConfig::Media(config) => Box::new(Media::from(*config)),