From 75cfd93ad1e4fc1e565fe92b464202bd3f48c9ec Mon Sep 17 00:00:00 2001
From: Levi Armstrong <levi.armstrong@gmail.com>
Date: Fri, 13 Sep 2024 14:07:05 -0500
Subject: [PATCH] Add timer class with callback

---
 tesseract_common/CMakeLists.txt               |  3 +-
 .../include/tesseract_common/timer.h          | 67 +++++++++++++++++++
 tesseract_common/src/timer.cpp                | 53 +++++++++++++++
 3 files changed, 122 insertions(+), 1 deletion(-)
 create mode 100644 tesseract_common/include/tesseract_common/timer.h
 create mode 100644 tesseract_common/src/timer.cpp

diff --git a/tesseract_common/CMakeLists.txt b/tesseract_common/CMakeLists.txt
index 4908038e196..f884bfbde5c 100644
--- a/tesseract_common/CMakeLists.txt
+++ b/tesseract_common/CMakeLists.txt
@@ -82,7 +82,8 @@ add_library(
   src/plugin_info.cpp
   src/resource_locator.cpp
   src/types.cpp
-  src/stopwatch.cpp)
+  src/stopwatch.cpp
+  src/timer.cpp)
 target_link_libraries(
   ${PROJECT_NAME}
   PUBLIC Eigen3::Eigen
diff --git a/tesseract_common/include/tesseract_common/timer.h b/tesseract_common/include/tesseract_common/timer.h
new file mode 100644
index 00000000000..74272666cf4
--- /dev/null
+++ b/tesseract_common/include/tesseract_common/timer.h
@@ -0,0 +1,67 @@
+/**
+ * @file timer.h
+ * @brief Simple timer class using chrono and thread
+ *
+ * @author Levi Armstrong
+ * @date February 2, 2021
+ * @version TODO
+ * @bug No known bugs
+ *
+ * @copyright Copyright (c) 2021, Southwest Research Institute
+ *
+ * @par License
+ * Software License Agreement (Apache License)
+ * @par
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * @par
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef TESSERACT_COMMON_TIMER_H
+#define TESSERACT_COMMON_TIMER_H
+
+#include <tesseract_common/macros.h>
+TESSERACT_COMMON_IGNORE_WARNINGS_PUSH
+#include <iostream>
+#include <functional>
+#include <chrono>
+#include <thread>
+#include <atomic>
+TESSERACT_COMMON_IGNORE_WARNINGS_POP
+
+namespace tesseract_common
+{
+/** @brief A timer which calls a callback every interval on a separate thread */
+class Timer
+{
+public:
+  Timer() = default;
+  ~Timer();
+  Timer(const Timer&) = delete;
+  Timer& operator=(const Timer&) = delete;
+  Timer(Timer&&) = delete;
+  Timer& operator=(Timer&&) = delete;
+
+  /**
+   * @brief Start the timer with a callback function and a std::chrono::duration interval
+   * @param callback The callback called every time the timer expires
+   * @param interval The interval at which the timer triggers
+   */
+  void start(const std::function<void()>& callback, std::chrono::steady_clock::duration interval);
+
+  /** @brief Stop the timer */
+  void stop();
+
+private:
+  std::atomic<bool> running_{ false };
+  std::thread timer_thread_;
+};
+
+}  // namespace tesseract_common
+#endif  // TESSERACT_COMMON_TIMER_H
diff --git a/tesseract_common/src/timer.cpp b/tesseract_common/src/timer.cpp
new file mode 100644
index 00000000000..24532e7fed3
--- /dev/null
+++ b/tesseract_common/src/timer.cpp
@@ -0,0 +1,53 @@
+/**
+ * @file timer.cpp
+ * @brief Simple timer class using chrono and thread
+ *
+ * @author Levi Armstrong
+ * @date February 2, 2021
+ * @version TODO
+ * @bug No known bugs
+ *
+ * @copyright Copyright (c) 2021, Southwest Research Institute
+ *
+ * @par License
+ * Software License Agreement (Apache License)
+ * @par
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * @par
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <tesseract_common/timer.h>
+
+namespace tesseract_common
+{
+Timer::~Timer() { stop(); }
+
+void Timer::start(const std::function<void()>& callback, std::chrono::steady_clock::duration interval)
+{
+  running_ = true;
+  timer_thread_ = std::thread([this, callback, interval]() {
+    while (running_)
+    {
+      auto next_time = std::chrono::steady_clock::now() + interval;
+      callback();  // Call the provided function
+      std::this_thread::sleep_until(next_time);
+    }
+  });
+}
+
+void Timer::stop()
+{
+  running_ = false;
+  if (timer_thread_.joinable())
+    timer_thread_.join();
+}
+
+}  // namespace tesseract_common