feat: Add battery module(#63)

src/main.rs

@@ -2,6 +2,7 @@
 extern crate clap;
 
 extern crate ansi_term;
+extern crate battery;
 extern crate dirs;
 extern crate git2;
 extern crate pretty_env_logger;

src/modules/battery.rs

@@ -0,0 +1,77 @@
+use ansi_term::Color;
+
+use super::{Context, Module};
+
+/// Creates a segment for the battery percentage and charging state
+pub fn segment(_context: &Context) -> Option<Module> {
+    const BATTERY_FULL: &str = "•";
+    const BATTERY_CHARGING: &str = "⇡";
+    const BATTERY_DISCHARGING: &str = "⇣";
+    const BATTERY_THRESHOLD: f32 = 10.0;
+
+    let battery_status = get_battery_status()?;
+    let BatteryStatus { state, percentage } = battery_status;
+
+    if percentage > BATTERY_THRESHOLD {
+        log::debug!(
+            "Battery percentage is higher than threshold ({} > {})",
+            percentage,
+            BATTERY_THRESHOLD
+        );
+        return None;
+    }
+
+    // TODO: Set style based on percentage when threshold is modifiable
+    let mut module = Module::new("battery");
+    module.set_style(Color::Red.bold());
+    module.get_prefix().set_value("");
+
+    match state {
+        battery::State::Full => {
+            module.new_segment("full", BATTERY_FULL);
+        }
+        battery::State::Charging => {
+            module.new_segment("charging", BATTERY_CHARGING);
+        }
+        battery::State::Discharging => {
+            module.new_segment("discharging", BATTERY_DISCHARGING);
+        }
+        _ => return None,
+    }
+
+    let mut percent_string = Vec::<String>::with_capacity(2);
+    // Round the percentage to a whole number
+    percent_string.push(percentage.round().to_string());
+    percent_string.push("%".to_string());
+    module.new_segment("percentage", percent_string.join(""));
+
+    Some(module)
+}
+
+fn get_battery_status() -> Option<BatteryStatus> {
+    let battery_manager = battery::Manager::new().ok()?;
+    match battery_manager.batteries().ok()?.next() {
+        Some(Ok(battery)) => {
+            log::debug!("Battery found: {:?}", battery);
+            let battery_status = BatteryStatus {
+                percentage: battery.state_of_charge().value * 100.0,
+                state: battery.state(),
+            };
+
+            Some(battery_status)
+        }
+        Some(Err(e)) => {
+            log::debug!("Unable to access battery information:\n{}", e);
+            None
+        }
+        None => {
+            log::debug!("No batteries found");
+            None
+        }
+    }
+}
+
+struct BatteryStatus {
+    percentage: f32,
+    state: battery::State,
+}

src/modules/mod.rs

@@ -1,3 +1,4 @@
+mod battery;
 mod character;
 mod directory;
 mod git_branch;
@@ -26,6 +27,7 @@ pub fn handle(module: &str, context: &Context) -> Option<Module> {
         "git_branch" => git_branch::segment(context),
         "git_status" => git_status::segment(context),
         "username" => username::segment(context),
+        "battery" => battery::segment(context),
 
         _ => panic!("Unknown module: {}", module),
     }

src/print.rs

@@ -8,6 +8,7 @@ use crate::modules;
 
 pub fn prompt(args: ArgMatches) {
     let prompt_order = vec![
+        "battery",
         "username",
         "directory",
         "git_branch",
@@ -22,10 +23,6 @@ pub fn prompt(args: ArgMatches) {
     ];
     let context = Context::new(args);
 
-    // TODO:
-    // - List files in directory
-    // - Index binaries in PATH
-
     let stdout = io::stdout();
     let mut handle = stdout.lock();