Improve how AT command responses are handled

src/at_commands.rs

@@ -1,19 +1,38 @@
-use alloc::format;
-use alloc::string::String;
+use alloc::string::{String, ToString};
 use alloc::vec::Vec;
+use alloc::{borrow::ToOwned, format};
 use core::fmt::Write;
 use esp_hal::{Blocking, delay::Delay, gpio::Output, uart::Uart};
 
 static RESPONSES: [&'static str; 3] = ["OK", "ERROR", "DOWNLOAD"];
 
 pub struct ATCommands<'a, 'd> {
-    pub rst: Output<'a>,
-    pub pwr_key: Output<'a>,
-    pub uart: Uart<'d, Blocking>,
-    pub delay: Delay,
+    rst: Output<'a>,
+    pwr_key: Output<'a>,
+    uart: Uart<'d, Blocking>,
+    delay: Delay,
+
+    buffer: String,
+    lines: Vec<String>,
 }
 
 impl<'a, 'd> ATCommands<'a, 'd> {
+    pub fn new(
+        rst: Output<'a>,
+        pwr_key: Output<'a>,
+        uart: Uart<'d, Blocking>,
+    ) -> ATCommands<'a, 'd> {
+        ATCommands {
+            rst,
+            pwr_key,
+            uart,
+            delay: Delay::new(),
+
+            buffer: String::new(),
+            lines: Vec::new(),
+        }
+    }
+
     pub fn init(&mut self) {
         self.pwr_key.set_low();
         self.delay.delay_millis(1_000);
@@ -38,11 +57,12 @@ impl<'a, 'd> ATCommands<'a, 'd> {
     pub fn raw_command(&mut self, command: String) -> String {
         self.uart.flush().unwrap();
         self.flush_rx();
-        self.uart.write_str(&(command.clone() + "\r")).unwrap();
+        let command = command.clone() + "\r";
+        self.uart.write_str(&command).unwrap();
         self.uart.flush().unwrap();
         self.delay.delay_millis(500);
         log::info!("Wrote command {}", command);
-        self.read_response()
+        self.read_response(command)
     }
 
     pub fn raw_two_part_command(&mut self, command: String, additional: String) -> String {
@@ -52,55 +72,86 @@ impl<'a, 'd> ATCommands<'a, 'd> {
         self.uart.flush().unwrap();
         self.delay.delay_millis(500);
         log::info!("Wrote command {}", command);
-        log::info!("{}", self.flush_rx());
+        self.flush_rx();
 
-        self.uart.write_str(&(additional.clone() + "\x1A")).unwrap();
+        let text = additional.clone() + "\x1A";
+        self.uart.write_str(&text).unwrap();
         self.uart.flush().unwrap();
 
-        self.read_response()
+        self.read_response(text)
     }
 
-    fn read_response(&mut self) -> String {
-        let mut buffer = [0u8; 1024];
-
-        let mut contents = String::new();
-
-        while {
-            let parts: Vec<&str> = contents.split("\r\n").collect();
-            !RESPONSES
-                .iter()
-                .any(|r| parts.iter().any(|p| p.contains(r)))
-        } {
-            let length = self.uart.read(&mut buffer).unwrap();
-            contents += str::from_utf8(&buffer[..length]).unwrap();
-            log::info!("Contents so far: {}", contents);
+    pub fn readline(&mut self) -> Option<String> {
+        self.flush_rx();
+        if self.lines.len() > 0 {
+            Some(self.lines.remove(0))
+        } else {
+            None
+        }
     }
 
-        let parts: Vec<&str> = contents.split("\r\n").collect();
-        let (idx, _) = parts
+    fn read_response(&mut self, start: String) -> String {
+        let mut response = None;
+        while response.is_none() {
+            self.flush_rx();
+            response = self.parse_response(&start);
+        }
+
+        response.unwrap()
+    }
+
+    fn parse_response(&mut self, start: &String) -> Option<String> {
+        let start_idx = self
+            .lines
             .iter()
             .enumerate()
-            .find(|(_, part)| RESPONSES.iter().any(|r| part.contains(r)))
-            .unwrap();
-        parts
-            .into_iter()
-            .take(idx + 1)
-            .collect::<Vec<_>>()
-            .join("\n")
+            .find(|(_, l)| l.starts_with(start))
+            .map(|(i, _)| i);
+
+        if let Some(start_idx) = start_idx {
+            let mut response = String::new();
+
+            for (i, line) in self.lines.iter().cloned().skip(start_idx).enumerate() {
+                if i == 0 {
+                    continue;
+                }
+                if response.len() > 0 {
+                    response += "\n";
+                }
+                response += &line;
+                if RESPONSES.iter().any(|r| line.starts_with(r)) {
+                    for _ in 0..=i {
+                        self.lines.remove(start_idx);
+                    }
+                    return Some(response);
+                }
+            }
         }
 
-    pub fn flush_rx(&mut self) -> String {
+        None
+    }
+
+    pub fn flush_rx(&mut self) {
         let mut buffer = [0u8; 1024];
 
-        let mut contents = String::new();
         while {
             self.delay.delay_millis(10);
             self.uart.read_ready()
         } {
             let length = self.uart.read(&mut buffer).unwrap();
-            contents += str::from_utf8(&buffer[..length]).unwrap();
+            self.buffer += str::from_utf8(&buffer[..length]).unwrap();
         }
 
-        contents
+        let lines = self
+            .buffer
+            .split("\n")
+            .map(|s| s.to_string())
+            .collect::<Vec<String>>();
+        self.buffer = lines.last().unwrap().to_string();
+
+        let full_lines_len = lines.len() - 1;
+        for line in lines.into_iter().take(full_lines_len) {
+            self.lines.push(line);
+        }
     }
 }

src/main.rs

@@ -126,12 +126,7 @@ fn main() -> ! {
     .with_rx(peripherals.GPIO7)
     .with_tx(peripherals.GPIO8);
 
-    let mut at_commands = ATCommands {
-        rst: sim_rst,
-        pwr_key: sim_pwr_key,
-        uart,
-        delay: Delay::new(),
-    };
+    let mut at_commands = ATCommands::new(sim_rst, sim_pwr_key, uart);
 
     let font_renderer = FontRenderer::create(30);
     display.clear(Rgb565::black().as_color());
@@ -290,5 +285,9 @@ fn thread_2_main(async_io: AsyncIO, mut at_commands: ATCommands<'static, 'static
             };
             unsafe { async_io.set_at_response(response) };
         }
+
+        if let Some(event) = at_commands.readline() {
+            log::info!("Event: {}", event);
+        }
     }
 }

src/states.rs

@@ -44,7 +44,9 @@ impl State for InitATState {
         // Wait for previous AT command to finish
         if let Some(response) = data.io.poll_at_response() {
             match response {
-                Some(_) => {}
+                Some(response) => {
+                    log::info!("Response: {}", response)
+                }
                 None => {}
             }
             return None;