Use clap to parse arguments

Cargo.toml

@@ -20,6 +20,8 @@ ws2818-rgb-led-spi-driver = { path = "./lib-ws2818-rgb-led-spi-driver" }
 common = { path = "./common" }
 webui = { path = "./webui" }
 dotenv = "0.15.0"
+clap = { version = "4.3.0", features = ["derive", "env"] }
+tracing = "0.1.37"
 
 [profile.release]
 lto = true

src/main.rs

@@ -33,6 +33,7 @@
 // mod pattern;
 mod strip;
 mod ui;
+use clap::Parser;
 use common::error::{self, ProgramError, ProgramResult};
 use std::{
     io,
@@ -47,31 +48,17 @@ fn main() -> ProgramResult<()> {
     // Initialize any config
     dotenv::dotenv().ok();
 
+    // Use clap to parse the configuration
+    let config = strip::Config::parse();
+
     // Strip control transmitter and receiver
     let (strip_tx, strip_rx) = channel::<common::strip::Message>();
     let (console_strip_tx, webui_strip_tx) = (strip_tx.clone(), strip_tx);
 
     let (message_tx, message_rx) = channel::<error::Message>();
 
-    let num_lights: u16 = std::env::var("NUM_LIGHTS")
-        .as_ref()
-        .map(String::as_str)
-        .unwrap_or("89")
-        .parse()
-        .unwrap();
-
-    eprintln!("Number of lights: {num_lights}");
-
     make_child(message_tx.clone(), move |message_tx| -> ProgramResult<()> {
-        let mut strip = LedStrip::new(strip::Config {
-            // I have 89 right now, but start off with 20
-            num_lights,
-            // Skip 14 lights
-            shift_lights: 14,
-            // Scaling factor (scale 0..255)
-            global_brightness_max: 255,
-            tick_time_ms: strip::DEFAULT_TICK_TIME_MS,
-        })?;
+        let mut strip = LedStrip::new(config)?;
         strip.strip_loop(message_tx, &strip_rx)
     });
 

src/strip.rs

@@ -1,3 +1,4 @@
+use clap::Parser;
 use common::{
     color, error,
     error::ProgramError,
@@ -21,15 +22,30 @@ pub const DEFAULT_TICK_TIME_MS: u64 = 10;
 /// Minimum time per tick before strip breaks
 pub const MIN_TICK_TIME: u64 = 10;
 
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Parser)]
 pub struct Config {
     /// Number of lights
+    #[clap(short = 'c', long, help = "Number of lights in the strip", value_parser = clap::value_parser!(u16).range(1..=(MAX_NUM_LIGHTS as i64)))]
     pub num_lights: u16,
     /// Number of lights to skip
+    #[clap(
+        short = 's',
+        long,
+        env,
+        default_value_t = 0,
+        help = "Number of lights to skip in the beginning"
+    )]
     pub shift_lights: u16,
     /// Global brightness multiplier
+    #[clap(
+        long,
+        env,
+        default_value_t = 255,
+        help = "The max brightness (clamped)"
+    )]
     pub global_brightness_max: u8,
     /// Time per tick
+    #[clap(long = "tick_time", env, default_value_t = DEFAULT_TICK_TIME_MS, help = "Tick time in milliseconds", value_parser = clap::value_parser!(u64).range(MIN_TICK_TIME..))]
     pub tick_time_ms: u64,
 }