started documentation effort

src/main.rs

@@ -1,10 +1,10 @@
+//! This file contains all driver code for the program.
 use core::time;
-use std::process::exit;
 use std::sync::Arc;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::thread;
 use clap::Parser;
-use log::{error, info};
+use log::{error, info, warn};
 use mpris::PlayerFinder;
 use structs::cli::Cli;
 use structs::{config::Config, data::Data};
@@ -19,13 +19,18 @@ mod print_text;
 mod structs;
 mod print_players;
 
+/// This function deals with an incoming (USR1) signal.
+/// It is hard-coded to play/payse the active player.
+/// 
+/// input:
+/// data: Data struct for active configuration.
 fn handle_signal(data: &Data) {
   if let Some(p) = &data.current_player {
     match p.checked_play_pause() {
         Ok(b) => {
           match b {
             true => info!("Player play/paused succesfully!"),
-            false => info!("Failed to send play/pause signal!"),
+            false => warn!("Failed to send play/pause signal!"),
         }
       },
         Err(e) => error!("{e}"),
@@ -33,26 +38,35 @@ fn handle_signal(data: &Data) {
   }
 }
 
+/// This function contains the default maim loop body of the program.
+/// It updates the active player, updates the output strings based on this, and finally formats and outputs these strings to stdout.
+/// 
+/// input:
+/// pf: PlayerFinder instance for the program
+/// cfg: Configuration of the program
+/// data: mutable Data struct, active state of the program
+/// r: pre-computed rating strings
 fn default_loop(pf: &PlayerFinder, cfg: &Config, data: &mut Data, r: &Vec<String>) {
   update_players(pf, cfg, data);
   update_message(cfg, data, r);
   print_text(cfg, data);
 }
 
+/// Main function. Mostly concerned with initialisation.
 fn main() {
+    // logging initialisation
     std::env::set_var("RUST_LOG", "error");
     if let Err(e) = env_logger::init() {
       error!("{e}");
       return
     }
 
+    // Cli flags, Config, Data, and PlayerFinder initialisation
     let cli = Cli::parse();
     match confy::load::<Config>("polybar-now-playing", cli.config_file.as_str()) {
       Ok(cfg) => {
         let mut data: Data = Data::default();
         let rating_strings = cfg.build_rating_strings();
-
-        let term = Arc::new(AtomicBool::new(false));
         
         let pf: PlayerFinder;        
         match PlayerFinder::new() {
@@ -63,11 +77,14 @@ fn main() {
             },
         }
 
+        // signal interception initialisation
+        let term = Arc::new(AtomicBool::new(false));
         if let Err(e) = signal_hook::flag::register(signal_hook::consts::SIGUSR1, Arc::clone(&term)) {
           error!("{e}");
           return
         }
 
+        // main body loop
         loop {
           thread::sleep(time::Duration::from_millis(cfg.update_delay));
           match cli.debug {