Add versioned host settings API for plugins

crates/ocs_plugin_api/src/ipc/client.rs

@@ -11,7 +11,7 @@ use acadrust::{CadDocument, EntityType, Handle};
 use interprocess::local_socket::traits::Stream as StreamTrait;
 use interprocess::local_socket::{GenericNamespaced, Stream, ToNsName};
 
-use crate::host::{DocumentReader, HostApi, InteractiveCommand, ReaderEntity};
+use crate::host::{DocumentReader, HostApi, HostSettingValue, InteractiveCommand, ReaderEntity};
 use crate::ipc::protocol::{
     HostResponse, HostToPlugin, PluginRequest, PluginResponse, PluginToHost, RunnerHandshake,
 };
@@ -416,6 +416,34 @@ impl HostApi for PluginHostApi {
             }
         }
     }
+
+    fn system_variable(&self, name: &str) -> Option<HostSettingValue> {
+        match self.client.request(PluginRequest::GetSystemVariable { name: name.to_owned() }) {
+            Ok(PluginResponse::SystemVariable(value)) => value,
+            _ => None,
+        }
+    }
+
+    fn set_system_variable(
+        &mut self,
+        name: &str,
+        value: HostSettingValue,
+    ) -> Result<HostSettingValue, String> {
+        match self.client.request(PluginRequest::SetSystemVariable {
+            name: name.to_owned(),
+            value,
+        }) {
+            Ok(PluginResponse::SystemVariableResult(result)) => {
+                if result.is_ok() {
+                    self.document_cache = OnceCell::new();
+                }
+                result
+            }
+            Ok(PluginResponse::Error(error)) => Err(error),
+            Ok(other) => Err(format!("unexpected system variable response: {other:?}")),
+            Err(error) => Err(error.to_string()),
+        }
+    }
 }
 
 /// Sentinel reader used when the shared-memory view could not be initialized.