Utilize async in state loop

src/states.rs

@@ -1,8 +1,12 @@
+use core::iter::repeat;
+
 use alloc::{
     borrow::ToOwned,
     boxed::Box,
+    format,
     string::{String, ToString},
 };
+use esp_hal::time::{Duration, Instant};
 
 use crate::{
     async_io::{ATCommand, SMSFormat},
@@ -12,36 +16,51 @@ use crate::{
 
 pub struct InitATState {
     inner_state: u8,
-    response: String,
+    message: String,
+    dots: u8,
+    prev_dots: Instant,
 }
 
 impl Default for InitATState {
     fn default() -> Self {
         Self {
             inner_state: 0,
-            response: "Initializing AT..".to_string(),
+            message: "Initializing AT..".to_string(),
+            dots: 0,
+            prev_dots: Instant::now(),
         }
     }
 }
 
 impl State for InitATState {
     fn update(&mut self, data: &mut StateData) -> Option<Box<dyn State>> {
+        // Update dots
+        if self.prev_dots.elapsed() > Duration::from_millis(200) {
+            self.dots = (self.dots + 1) % 3;
+            self.prev_dots = Instant::now();
+        }
+
+        // Wait for previous AT command to finish
         if let Some(response) = data.io.poll_at_response() {
             match response {
-                Some(response) => self.response = response,
+                Some(_) => {}
                 None => {}
             }
             return None;
         }
+
+        // Send next AT command
         let res: Option<Box<dyn State>> = match self.inner_state {
             0 => {
                 data.io.send_at_command(ATCommand::ATInformation).unwrap();
+                self.message = "Checking info".to_owned();
                 None
             }
             1 => {
                 data.io
                     .send_at_command(ATCommand::EnterPin("1234".to_owned()))
                     .unwrap();
+                self.message = "Entering PIN".to_owned();
                 None
             }
             2 => {
@@ -52,12 +71,14 @@ impl State for InitATState {
                 data.io
                     .send_at_command(ATCommand::ListTECharacterSets)
                     .unwrap();
+                self.message = "Checking\ncharsets".to_owned();
                 None
             }
             4 => {
                 data.io
                     .send_at_command(ATCommand::SelectSMSFormat(SMSFormat::TextMode))
                     .unwrap();
+                self.message = "Selecting SMS\nformat".to_owned();
                 None
             }
             _ => {
@@ -74,7 +95,12 @@ impl State for InitATState {
 
     fn draw(&self, data: &mut StateData) {
         data.clear_screen(Rgb565::black().as_color());
-        data.draw_text(&self.response, Position::new(0, 0), TextSettings::default());
+        let dots = repeat(".").take(self.dots as usize).collect::<String>();
+        data.draw_text(
+            format!("{}{}", self.message, dots),
+            Position::new(0, 0),
+            TextSettings::default(),
+        );
     }
 }