#include <chrono> //time measurement
#include <fstream> // reading from serial port

#include "rclcpp/rclcpp.hpp"
#include "std_msgs/msg/string.hpp"

using namespace std::chrono_literals; // for time measurements

class HeightSensorPublisher : public rclcpp::Node
{
	public:
		HeightSensorPublisher() : Node("height_sensor_publisher")
			{
				publisher_ = this->create_publisher<std_msgs::msg::String>("height_sensor", 10);
				timer_ = this->create_wall_timer(
					500ms, std::bind(&HeightSensorPublisher::timer_callback, this));
				RCLCPP_INFO(this->get_logger(), "Constructor of height sensor publisher");	

				setup_serial_port();

			}
	private:


		/**
		 * @brief Timer callback function to publish the height sensor data
		 * 
		 */
		void timer_callback()
		{
			char* readdata = new char[1];
			serial_port.read(readdata, 1);
			auto message = std_msgs::msg::String();
			message.data = "Height: " + std::to_string((int)readdata[0]);
			RCLCPP_INFO(this->get_logger(), "Publishing: %s", message.data.c_str());
			publisher_->publish(message);
		}

		/**
		 * @brief Set the up serial port object to read from the sensor (/dev/ttyACM0)
		 * 
		 */
		void setup_serial_port() 
		{
			serial_port.open("/dev/ttyACM0", std::ios::in);
			if (!serial_port.is_open())
			{
				RCLCPP_ERROR(this->get_logger(), "Could not open serial port");
				return;
			}
			else
			{
				RCLCPP_INFO(this->get_logger(), "Serial port opened");
			}

			serial_port.close();
		}
		rclcpp::TimerBase::SharedPtr timer_;
		rclcpp::Publisher<std_msgs::msg::String>::SharedPtr publisher_;
		std::fstream serial_port; // serial port for reading from device
};

int main(int argc, char *argv[])
{
	rclcpp::init(argc,argv);
	rclcpp::spin(std::make_shared<HeightSensorPublisher>());
	rclcpp::shutdown();

	return 0;
}