fix join null check and expose current task uuid in worker

src/actsim_agent/uploader.cpp

@@ -37,7 +37,7 @@ void Uploader::start() {
 }
 
 void Uploader::join() {
-    if (this->uploader_thread != nullptr) return;
+    if (this->uploader_thread == nullptr) return;
     this->uploader_thread->join();
 }
 
@@ -99,6 +99,9 @@ void Uploader::thread_run() {
 }
 
 bool Uploader::upload_task([[maybe_unused]]std::unique_ptr<Task> task) {
+
+    // make sure any task that is uploaded isn't halted in the database
+
     std::cout << "Task uploaded!";
     return true;
 }

src/actsim_agent/worker.cpp

@@ -31,15 +31,17 @@ Worker::Worker(TaskInterface& interface) : interface(interface) {}
 
 void Worker::start() {
     std::cout << "Worker started" << std::endl;
-    this->worker_thread = std::make_unique<std::thread>([this]() { thread_run(); });
+    this->worker_thread = std::make_unique<std::thread>([this] () { this->thread_run(); });
 }
 
 void Worker::cancel_current() {
     std::cout << "Current simulation cancelled." << std::endl;
+    // set a condition variable and notify
+    // must not be blocking
 }
 
 void Worker::join() {
-    if (this->worker_thread != nullptr) return;
+    if (this->worker_thread == nullptr) return;
     this->worker_thread->join();
 }
 
@@ -55,12 +57,14 @@ void Worker::thread_run() {
         // we're still good to go! get a task from the fresh queue
         bool queue_empty;
         auto task = this->interface.pop_fresh(queue_empty);
+        this->current_task.store(task->uuid, std::memory_order_relaxed);
 
         // we need to make sure the queue wasn't emptied between waiting and getting new data
         if (queue_empty) continue;
 
         // everything is good, perform the given task
         bool complete = this->perform_task(task);
+        this->current_task.store(db::uuid_t(), std::memory_order_relaxed);
 
         // if the task was finished, push the task to be uploaded
         // we need this since the task might have been interrupted
@@ -70,8 +74,11 @@ void Worker::thread_run() {
 }
 
 bool Worker::perform_task(std::unique_ptr<Task>& task) {
-    std::cout << "Worker ping" << std::endl;
     usleep(100000);
-    task->get_uuid();
+    std::cout << "Worker performed task. Please implement me!" << std::endl;
+    task->uuid;
     return true;
+
+    // wait for either the executing process to finish or 
+    // for the condition variable indicating the process should be stopped
 }