feat: Create GPIO monitor and basic callback functionality to print

src/main.rs

@@ -0,0 +1,33 @@
+mod gpio;
+
+use std::time::Duration;
+
+use anyhow::Result;
+use tracing::{error, info};
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    // Initialize logging
+    tracing_subscriber::fmt::init();
+
+    // Initialize GPIO monitor
+    const DEFAULT_GPIO_PIN: u8 = 17;
+    let gpio_pin = std::env::var("GPIO_PIN")
+        .ok()
+        .and_then(|v| v.parse().ok())
+        .unwrap_or(DEFAULT_GPIO_PIN);
+
+    let mut gpio_monitor = gpio::GpioMonitor::new(gpio_pin, Duration::from_millis(100))?;
+
+    // Simple callback function that just logs the event
+    let callback = |event: gpio::CircuitEvent| {
+        info!("Circuit state changed: {:?}", event);
+    };
+
+    // Start GPIO monitoring
+    if let Err(e) = gpio_monitor.monitor(callback).await {
+        error!("GPIO monitoring error: {}", e);
+    }
+
+    Ok(())
+}