[feat] acknowledge remote input and wait for visual changes

libs/controller/src/controller_requests.cpp

@@ -0,0 +1,56 @@
+#include "controller_session.h"
+#include <stream_names.h>
+
+namespace crossdesk {
+using nlohmann::json;
+
+uint64_t ControllerSession::RequestRemote(const std::string &method, json arguments) {
+  if (!Connected() || remote_results_.size() >= 512) return 0;
+  const auto id = ++remote_sequence_;
+  remote_results_[id] = nullptr;
+  const auto message = json{{"type", "automation"}, {"version", 1},
+      {"id", id}, {"method", method}, {"arguments", std::move(arguments)}}.dump();
+  if (!Send(kControlStream, message)) {
+    remote_results_.erase(id);
+    return 0;
+  }
+  return id;
+}
+
+std::optional<json> ControllerSession::TakeRemoteResult(uint64_t request) {
+  const auto found = remote_results_.find(request);
+  if (found == remote_results_.end() || found->second.is_null()) return {};
+  auto result = std::move(found->second);
+  remote_results_.erase(found);
+  return result;
+}
+
+void ControllerSession::BeginInput() {
+  for (const auto id : input_requests_) remote_results_.erase(id);
+  input_requests_.clear();
+  input_result_ = "applied";
+  input_ack_active_ = InputAcknowledged();
+}
+
+bool ControllerSession::SendInput(const char *stream, const RemoteAction &action) {
+  if (!input_ack_active_) return Send(stream, action.to_json());
+  const auto id = RequestRemote("input", json::parse(action.to_json()));
+  if (!id) return false;
+  input_requests_.push_back(id);
+  return true;
+}
+
+std::string ControllerSession::InputResult() {
+  if (!input_ack_active_) return "unsupported";
+  for (auto it = input_requests_.begin(); it != input_requests_.end();) {
+    auto reply = TakeRemoteResult(*it);
+    if (!reply) { ++it; continue; }
+    const auto result = reply->value("result", json{});
+    if (reply->value("ok", json{}) != true || !result.is_object() ||
+        result.value("state", json{}) != "applied")
+      input_result_ = "failed";
+    it = input_requests_.erase(it);
+  }
+  return input_requests_.empty() ? input_result_ : "pending";
+}
+} // namespace crossdesk