feat: default meters + update state on link

src/dsp408/client/dsp408.rs

@@ -10,8 +10,7 @@ use std::{
 use crate::{
     common::errors::DSPError,
     dsp408::{
-        default::default_input_meters,
-        default::default_output_meters,
+        default::{default_input_meters, default_output_meters},
         default_dsp_state,
         mapper::{
             self,
@@ -19,7 +18,7 @@ use crate::{
             response::map_response,
         },
         protocol::{commands, config::decode_config, frame::extract_frame},
-        types::{self},
+        types::self,
     },
 };
 
@@ -1514,9 +1513,6 @@ impl DSP408 {
                 if !self.request_acknowledgement()? {
                     return Ok(false);
                 }
-
-                let config = self.read_config_state()?;
-                self.state_mut().current_config = config;
             }
 
             types::DSPMode::Demo => {
@@ -1528,6 +1524,54 @@ impl DSP408 {
             }
         }
 
+        let state = self.state_mut();
+
+        match source {
+            types::Channel::Input(s) => {
+                let input_destinations: Vec<types::InputChannel> = destinations
+                    .iter()
+                    .filter_map(|destination| match destination {
+                        types::Channel::Input(input) => Some(*input),
+                        types::Channel::Output(_) => None,
+                    })
+                    .collect();
+
+                let states = &mut state.current_config.input_states;
+
+                // Remove the source and destinations from all existing links.
+                for channel_state in states.values_mut() {
+                    channel_state
+                        .linked_channels
+                        .retain(|channel| *channel != s && !input_destinations.contains(channel));
+                }
+
+                // Link source -> destinations.
+                states.get_mut(&s).unwrap().linked_channels = input_destinations;
+            }
+
+            types::Channel::Output(s) => {
+                let output_destinations: Vec<types::OutputChannel> = destinations
+                    .iter()
+                    .filter_map(|destination| match destination {
+                        types::Channel::Output(output) => Some(*output),
+                        types::Channel::Input(_) => None,
+                    })
+                    .collect();
+
+                let states = &mut state.current_config.output_states;
+
+                // Remove the source and destinations from all existing links.
+                for channel_state in states.values_mut() {
+                    channel_state
+                        .linked_channels
+                        .retain(|channel| *channel != s && !output_destinations.contains(channel));
+                }
+
+                // Link source -> destinations.
+                states.get_mut(&s).unwrap().linked_channels = output_destinations;
+            }
+        }
+
         Ok(true)
     }