initial commit

1 files changed, 82 insertions, 0 deletions

diff --git a/main.rs b/main.rs
new file mode 100644
index 0000000..d6bf3d9
--- /dev/null
+++ b/main.rs
@@ -0,0 +1,82 @@
+use std::{
+    collections::HashMap, env, fs::File, io::Read, process::Command, thread::sleep, time::Duration,
+};
+
+fn main() {
+    let mut args = env::args();
+
+    assert!(
+        args.len() > 2,
+        "Too few arguments, provide battery id and values with warning levels"
+    );
+    // Skip process (argc[0])
+    args.next();
+
+    // 1: Battery ID
+    let bat = args.next().expect("Invalid Battery id");
+    let bat_path = format!("/sys/class/power_supply/{bat}");
+    let cap_path = format!("{bat_path}/capacity");
+    let status_path = format!("{bat_path}/status");
+
+    // 2: Sleep
+    let sleep_secs = args
+        .next()
+        .expect("Invalid sleep duration")
+        .parse::<u64>()
+        .expect("Invalid sleep value");
+
+    let mut warnings: HashMap<u8, String> = HashMap::new();
+    for arg in args {
+        let (lvl, value) = arg.split_at(1);
+        assert!(
+            lvl == "l" || lvl == "n" || lvl == "c",
+            "Unknown notification level"
+        );
+        warnings.insert(
+            value.parse::<u8>().expect("Invalid battery value"),
+            lvl.to_string(),
+        );
+    }
+
+    let mut cap_cache = String::new();
+    loop {
+        let cur_cap = read_file(&cap_path);
+        if cur_cap != cap_cache {
+            cap_cache.clone_from(&cur_cap);
+            if &read_file(&status_path) == "Charging" { continue; };
+            let val = cur_cap
+                .parse::<u8>()
+                .expect("Couldn't parse capacity value");
+            if let Some(lvl) = warnings.get(&val) {
+                notify(lvl, val);
+            };
+        }
+        sleep(Duration::from_secs(sleep_secs));
+    }
+}
+
+fn read_file(path: &str) -> String {
+    let mut f = File::open(path).expect("Could't open file");
+    let mut buf = String::new();
+    f.read_to_string(&mut buf).expect("Couldn't read file");
+    buf.trim().to_string()
+}
+
+fn notify(lvl: &str, remaining: u8) {
+    let urgency = match lvl {
+        "l" => "low",
+        "n" => "normal",
+        "c" => "critical",
+        _ => unreachable!(),
+    };
+    let notif = format!("Remaining battery capacity: {remaining}");
+    Command::new("notify-send")
+        .arg("--app-name=esbnd")
+        .arg("--category=device")
+        .arg("--icon=battery-low-symbolic")
+        .arg("-u")
+        .arg(urgency)
+        .arg(notif)
+        .spawn()
+        .expect("Couldn't send notification");
+}