From 8f7076cd0972608c0010bc73e41ab846d9b5b2c3 Mon Sep 17 00:00:00 2001
From: Dan Paulat <dpaulat@gmail.com>
Date: Sat, 18 May 2024 11:08:48 -0500
Subject: [PATCH] Add thread manager for QThreads

---
 scwx-qt/scwx-qt.cmake                         |  2 +
 scwx-qt/source/scwx/qt/main/main.cpp          |  4 +
 .../source/scwx/qt/manager/thread_manager.cpp | 83 +++++++++++++++++++
 .../source/scwx/qt/manager/thread_manager.hpp | 37 +++++++++
 4 files changed, 126 insertions(+)
 create mode 100644 scwx-qt/source/scwx/qt/manager/thread_manager.cpp
 create mode 100644 scwx-qt/source/scwx/qt/manager/thread_manager.hpp

diff --git a/scwx-qt/scwx-qt.cmake b/scwx-qt/scwx-qt.cmake
index 47340552..cb48e893 100644
--- a/scwx-qt/scwx-qt.cmake
+++ b/scwx-qt/scwx-qt.cmake
@@ -99,6 +99,7 @@ set(HDR_MANAGER source/scwx/qt/manager/alert_manager.hpp
                 source/scwx/qt/manager/resource_manager.hpp
                 source/scwx/qt/manager/settings_manager.hpp
                 source/scwx/qt/manager/text_event_manager.hpp
+                source/scwx/qt/manager/thread_manager.hpp
                 source/scwx/qt/manager/timeline_manager.hpp
                 source/scwx/qt/manager/update_manager.hpp)
 set(SRC_MANAGER source/scwx/qt/manager/alert_manager.cpp
@@ -113,6 +114,7 @@ set(SRC_MANAGER source/scwx/qt/manager/alert_manager.cpp
                 source/scwx/qt/manager/resource_manager.cpp
                 source/scwx/qt/manager/settings_manager.cpp
                 source/scwx/qt/manager/text_event_manager.cpp
+                source/scwx/qt/manager/thread_manager.cpp
                 source/scwx/qt/manager/timeline_manager.cpp
                 source/scwx/qt/manager/update_manager.cpp)
 set(HDR_MAP source/scwx/qt/map/alert_layer.hpp
diff --git a/scwx-qt/source/scwx/qt/main/main.cpp b/scwx-qt/source/scwx/qt/main/main.cpp
index 2d8073da..b6dcf5f0 100644
--- a/scwx-qt/source/scwx/qt/main/main.cpp
+++ b/scwx-qt/source/scwx/qt/main/main.cpp
@@ -7,6 +7,7 @@
 #include <scwx/qt/manager/radar_product_manager.hpp>
 #include <scwx/qt/manager/resource_manager.hpp>
 #include <scwx/qt/manager/settings_manager.hpp>
+#include <scwx/qt/manager/thread_manager.hpp>
 #include <scwx/qt/settings/general_settings.hpp>
 #include <scwx/qt/types/qt_types.hpp>
 #include <scwx/qt/ui/setup/setup_wizard.hpp>
@@ -129,6 +130,9 @@ int main(int argc, char* argv[])
    // Deinitialize application
    scwx::qt::manager::RadarProductManager::Cleanup();
 
+   // Stop Qt Threads
+   scwx::qt::manager::ThreadManager::Instance().StopThreads();
+
    // Gracefully stop the io_context main loop
    work.reset();
    threadPool.join();
diff --git a/scwx-qt/source/scwx/qt/manager/thread_manager.cpp b/scwx-qt/source/scwx/qt/manager/thread_manager.cpp
new file mode 100644
index 00000000..8b12edb0
--- /dev/null
+++ b/scwx-qt/source/scwx/qt/manager/thread_manager.cpp
@@ -0,0 +1,83 @@
+#include <scwx/qt/manager/thread_manager.hpp>
+#include <scwx/util/logger.hpp>
+
+#include <mutex>
+
+#include <boost/unordered/unordered_flat_map.hpp>
+#include <QThread>
+
+namespace scwx
+{
+namespace qt
+{
+namespace manager
+{
+
+static const std::string logPrefix_ = "scwx::qt::manager::thread_manager";
+static const auto        logger_    = scwx::util::Logger::Create(logPrefix_);
+
+class ThreadManager::Impl
+{
+public:
+   explicit Impl() {}
+   ~Impl() {}
+
+   std::mutex mutex_ {};
+
+   boost::unordered_flat_map<std::string, QThread*> threadMap_ {};
+};
+
+ThreadManager::ThreadManager() : p(std::make_unique<Impl>()) {}
+ThreadManager::~ThreadManager() = default;
+
+QThread* ThreadManager::thread(const std::string& id, bool autoStart)
+{
+   std::unique_lock lock {p->mutex_};
+   QThread*         thread = nullptr;
+
+   auto it = p->threadMap_.find(id);
+   if (it != p->threadMap_.cend())
+   {
+      thread = it->second;
+   }
+
+   if (thread == nullptr)
+   {
+      logger_->debug("Creating thread: {}", id);
+
+      thread = new QThread(this);
+      p->threadMap_.insert_or_assign(id, thread);
+
+      if (autoStart)
+      {
+         thread->start();
+      }
+   }
+
+   return thread;
+}
+
+void ThreadManager::StopThreads()
+{
+   std::unique_lock lock {p->mutex_};
+
+   logger_->debug("Stopping threads");
+
+   for (auto& thread : p->threadMap_)
+   {
+      thread.second->quit();
+      thread.second->deleteLater();
+   }
+
+   p->threadMap_.clear();
+}
+
+ThreadManager& ThreadManager::Instance()
+{
+   static ThreadManager threadManager_ {};
+   return threadManager_;
+}
+
+} // namespace manager
+} // namespace qt
+} // namespace scwx
diff --git a/scwx-qt/source/scwx/qt/manager/thread_manager.hpp b/scwx-qt/source/scwx/qt/manager/thread_manager.hpp
new file mode 100644
index 00000000..496d30ba
--- /dev/null
+++ b/scwx-qt/source/scwx/qt/manager/thread_manager.hpp
@@ -0,0 +1,37 @@
+#pragma once
+
+#include <memory>
+
+#include <QObject>
+#include <QThread>
+
+namespace scwx
+{
+namespace qt
+{
+namespace manager
+{
+
+class ThreadManager : public QObject
+{
+   Q_OBJECT
+   Q_DISABLE_COPY_MOVE(ThreadManager)
+
+public:
+   explicit ThreadManager();
+   ~ThreadManager();
+
+   QThread* thread(const std::string& id, bool autoStart = true);
+
+   void StopThreads();
+
+   static ThreadManager& Instance();
+
+private:
+   class Impl;
+   std::unique_ptr<Impl> p;
+};
+
+} // namespace manager
+} // namespace qt
+} // namespace scwx