Clean up code

red/src/printer/mod.rs

@@ -22,6 +22,7 @@ use self::gcode::{G0Command, G28Command, G90Command, GcodeReplyError};
 /// This should fit a simple "OK Pnn Bn" reply for GCODE commands that
 /// do not return any data.
 const RECV_BUFFER_CAPACITY: usize = 32;
+const BAUD_RATE: u32 = 115200;
 
 #[derive(Debug)]
 pub enum PrinterError {
@@ -32,8 +33,11 @@ pub enum PrinterError {
     // If the "ok" line can't be parsed
     ConfirmationError { parsed_string: String },
     NoResponseFromPrinter(String),
+    // If the initial printer configuration fails
+    InitializationError(String),
 }
 
+#[derive(Debug, Clone, Copy)]
 pub struct PrinterPosition {
     x: f64,
     y: f64,
@@ -86,10 +90,7 @@ impl Printer {
     }
 
     pub async fn connect(port_path: &str) -> Result<Self, PrinterError> {
-        // TODO: implement auto position reporting.
-        //  For this the whole reply-response control flow won't really work anymore, since the
-        //  replies will just be interlaced with position reports.
-        let mut port = tokio_serial::new(port_path, 115200)
+        let mut port = tokio_serial::new(port_path, BAUD_RATE)
             .open_native_async()
             .expect("Unable to open serial port");
 
@@ -141,13 +142,24 @@ impl Printer {
             maximum_buffer_capacity: 0, // this is updated on the next call to `send_gcode()`
         };
 
-        res.send_gcode(G91Command)
-            .await
-            .expect("Could not ask for current position!");
+        // This implicitly sets `res.last_buffer_capacity`
+        res.use_absolute_movements().await.map_err(|err| {
+            PrinterError::InitializationError(format!(
+                "Failed to set absolute movements mode: {:?}",
+                err
+            ))
+        })?;
 
         // since we never sent any positioning GCODE, we should be at max-capacity now.
         res.maximum_buffer_capacity = res.last_buffer_capacity;
 
+        res.update_position().await.map_err(|err| {
+            PrinterError::InitializationError(format!(
+                "Failed to get the current position: {:?}",
+                err
+            ))
+        })?;
+
         Ok(res)
     }
 
@@ -180,6 +192,13 @@ impl Printer {
             .map_err(|_| make_err())
     }
 
+    /// Update the internal position by asking the printer for it
+    async fn update_position(&mut self) -> Result<PrinterPosition, PrinterError> {
+        let res = self.send_gcode(M114Command).await?;
+        self.state.position = res;
+        Ok(res)
+    }
+
     /// Switch the printer to absolute movement mode.
     ///
     /// This is generally necessary before sending consecutive `self.move_absolute()` commands.
@@ -208,13 +227,13 @@ impl Printer {
     /// * `x, y, z` - Whether the axis should be homed. Axis that are set to `false` will not be
     /// homed.,
     pub async fn auto_home(&mut self, x: bool, y: bool, z: bool) -> Result<(), PrinterError> {
-        let res = self.send_gcode(G28Command::new(x, y, z)).await?;
+        self.send_gcode(G28Command::new(x, y, z)).await?;
         self.state.position = PrinterPosition {
             x: 0.0,
             y: 0.0,
             z: 0.0,
         };
-        Ok(res)
+        Ok(())
     }
 
     /// Move the printer by a specific distance
@@ -241,7 +260,7 @@ impl Printer {
             e: None, // Machine has no e
             velocity,
         };
-        let reply = if let MovementMode::AbsoluteMovements = self.state.movement_mode {
+        if let MovementMode::AbsoluteMovements = self.state.movement_mode {
             self.use_relative_movements().await?;
             let res = self.send_gcode(command).await;
             self.use_absolute_movements().await?;
@@ -254,7 +273,7 @@ impl Printer {
         self.state.position.y += y;
         self.state.position.z += z;
 
-        Ok(reply)
+        Ok(())
     }
     /// Move the printer to a specific position
     ///
@@ -279,7 +298,7 @@ impl Printer {
             e: None, // Machine has no e
             velocity: Some(velocity),
         };
-        let reply = if let MovementMode::RelativeMovements = self.state.movement_mode {
+        if let MovementMode::RelativeMovements = self.state.movement_mode {
             self.use_absolute_movements().await?;
             let res = self.send_gcode(command).await;
             self.use_relative_movements().await?;
@@ -292,7 +311,7 @@ impl Printer {
         self.state.position.y = y;
         self.state.position.z = z;
 
-        Ok(reply)
+        Ok(())
     }
 }