From 94c3a090542ab273db6fa0bdf234a4f7468406ed Mon Sep 17 00:00:00 2001
From: Giulio Eulisse <10544+ktf@users.noreply.github.com>
Date: Tue, 25 Jan 2022 17:27:54 +0100
Subject: [PATCH] GUI Controller

provide a controller which can be used to control state
transitions from an external GUI.
---
 fairmq/plugins/control/Control.cxx | 25 +++++++++++++++++++++++++
 fairmq/plugins/control/Control.h   |  1 +
 2 files changed, 26 insertions(+)

diff --git a/fairmq/plugins/control/Control.cxx b/fairmq/plugins/control/Control.cxx
index cd5204cf..61090a25 100644
--- a/fairmq/plugins/control/Control.cxx
+++ b/fairmq/plugins/control/Control.cxx
@@ -72,6 +72,9 @@ Control::Control(const string& name, Plugin::Version version, const string& main
         if (control == "static") {
             LOG(debug) << "Running builtin controller: static";
             fControllerThread = thread(&Control::StaticMode, this);
+        } else if (control == "gui") {
+            LOG(debug) << "Running builtin controller: gui";
+            fControllerThread = thread(&Control::GUIMode, this);
         } else if (control == "dynamic" || control == "external" || control == "interactive") {
             LOG(debug) << "Running builtin controller: interactive";
             fControllerThread = thread(&Control::InteractiveMode, this);
@@ -380,6 +383,28 @@ try {
     ReleaseDeviceControl();
 }
 
+auto Control::GUIMode() -> void
+try {
+    RunStartupSequence();
+
+    {
+        // Wait for next state, which is DeviceState::Ready,
+        // or for device shutdown request (Ctrl-C)
+        pair<bool, fair::mq::State> result;
+        do {
+            result = fStateQueue.WaitForNext(chrono::milliseconds(50));
+        } while (!fDeviceShutdownRequested);
+    }
+
+    RunShutdownSequence();
+} catch (PluginServices::DeviceControlError& e) {
+    // If we are here, it means another plugin has taken control. That's fine, just print the
+    // exception message and do nothing else.
+    LOG(debug) << e.what();
+} catch (DeviceErrorState&) {
+    ReleaseDeviceControl();
+}
+
 auto Control::SignalHandler() -> void
 {
     while (gSignalCount == 0 && !fPluginShutdownRequested) {
diff --git a/fairmq/plugins/control/Control.h b/fairmq/plugins/control/Control.h
index 61439d9f..b1c7d24d 100644
--- a/fairmq/plugins/control/Control.h
+++ b/fairmq/plugins/control/Control.h
@@ -43,6 +43,7 @@ class Control : public Plugin
     static auto PrintStateMachine() -> void;
     auto PrintNumberOfConnectedPeers() -> void;
     auto StaticMode() -> void;
+    auto GUIMode() -> void;
     auto SignalHandler() -> void;
     auto RunShutdownSequence() -> void;
     auto RunStartupSequence() -> void;