/*
 * task.hpp
 *
 *  Created on: Sep 14, 2023
 *      Author: Dario
 */

#ifndef INCLUDE_TACOS_TASK_HPP_
#define INCLUDE_TACOS_TASK_HPP_

#include <cmsis_os2.h>

#include <sta/config.hpp>
#include <sta/rtos/thread.hpp>
#include <sta/rtos/queue.hpp>
#include <sta/rtos/system/can_bus.hpp>

/**
 * @defgroup tacos_thread TACOS Thread
 * @ingroup tacos
 * @brief TACOS Thread class.
 */

namespace sta
{
	namespace tacos
	{
#ifdef STA_TACOS_WATCHDOG_ENABLED
		/**
		 * @brief A status flags for the watchdog.
		 * 
		 * @ingroup tacos_thread
		 */
		enum class ThreadStatus
		{
			/**
			 * @brief This thread wants to be ignored by the watchdog.
			 * 
			 */
			IGNORED,

			/**
			 * @brief The thread terminated regularly. The watchdog will not try to restart this thread.
			 * 
			 */
			STOPPED,

			/**
			 * @brief The thread's status is unknown. If the watchdog encounters this status, it will try to
			 * restart the affected thread.
			 * 
			 */
			UNKNOWN,

			/**
			 * @brief The thread is running as intended. The watchdog will set this flag back to UNKNOWN.
			 * 
			 */
			RUNNING,

			/**
			 * @brief The thread is waiting and might not send a heartbeat signal in a while. The watchdog will
			 * not do anything in this case.
			 * 
			 */
			WAITING
		};
#endif // STA_TACOS_WATCHDOG_ENABLED

		/**
		 * @brief Abstract class for thread implementations in Tacos.
		 *
		 * @ingroup tacos_thread
		 */
		class TacosThread : public RtosThread
		{
		public:
			/**
			 * @brief Create a new thread with the given name and priority.
			 * 
			 * @param name The thread's name. This is used for debugging.
			 * @param prio The thread's priority. Generally, this should be lower than the manager and statemachine priority.
			 * @param stack_size The stack size for the task. The default is 0, i.e. the stack size specified in the FreeRTOS settings.
			 * @param cb_size The control block size for the task. The default is 0, i.e. the size specified in the FreeRTOS settings.
			 */
			TacosThread(const char* name, osPriority_t prio, uint32_t stack_size = 0, uint32_t cb_size = 0);

			virtual ~TacosThread();

			/**
			 * @brief Checks if this thread is currently running.
			 */
			bool isRunning();

			bool operator==(const TacosThread& other) const;

			/**
			 * @brief Compare two threads by their names.
			 */
			bool operator<(const TacosThread& other) const;

			void loop() override;

			void start() override;

			/**
			 * @brief This function is executed first when this thread is started.
			 */
			virtual void init();

			/**
			 * @brief The body of the thread's loop. Has to be implemented by the user.
			 *	 	This function is called repeatedly until termination is requested.
			 */
			virtual void func() = 0;

			/**
			 * @brief This function is executed when the thread is terminated. Has to be implemented by the user.
			 * 		This function should free all ressources used by this thread.
			 */
			virtual void cleanup();

			/**
			 * @brief Sleep for a given number of ticks. Sets itself to WAITING if the watchdog is enabled, preventing
			 * the watchdog from restarting this thread.
			 * 
			 * @param ticks 
			 */
			void sleep(uint32_t ticks);

			/**
			 * @brief Sleep until next period. Sets itself to WAITING if the watchdog is enabled, preventing
			 * the watchdog from restarting this thread.
			 * 
			 * @param frequency 
			 */
			void periodicDelay(uint32_t frequency);

#ifdef STA_CAN_BUS_ENABLE
			/**
			 * @brief Set the ID of the CAN bus this thread is associated with.
			 * 
			 * @param canID 
			 */
			void setCanID(uint32_t canID);

			/**
			 * @brief Get the ID of the CAN bus this thread is associated with.
			 * 
			 * @return can ID 
			 */
			uint32_t getCanID();

			sta::RtosQueue<CanSysMsg> CAN_queue_;
#endif // STA_CAN_BUS_ENABLE

#ifdef STA_TACOS_WATCHDOG_ENABLED
			/**
			 * @brief This macro wraps a given statement into waiting() and heartbeat() to make the code more readable.
			 * 
			 */
			#define blocking(...) \
				waiting(); \
				__VA_ARGS__ \
				heartbeat(); \

		protected:
			/**
			 * @brief Sends a heartbeat signal by setting the thread status to RUNNING
			 * 
			 */
			void heartbeat();

			/**
			 * @brief Set the thread's status to waiting. This can called before executing code which is very likely
			 * to exceed a watchdog cycle. This stops the watchdog from restarting the thread.
			 * 
			 */
			void waiting();
		public:
			/**
			 * @brief Get the current status of the thread.
			 * 
			 * @return ThreadStatus The current status of the thread.
			 */
			ThreadStatus getStatus();

			/**
			 * @brief Reset the thread's status to UNKNOWN. Should only be called by the Watchdog.
			 * 
			 */
			void resetStatus();

			/**
			 * @brief This thread status tells the watchdog to ignore this thread.
			 */
			void watchdogIgnore();
#endif // STA_TACOS_WATCHDOG_ENABLED

			/**
			 * @brief Send termination request to thread.
			 */
			void requestTermination();

			/**
			 * @brief Clear the termination request flag for this thread.
			 */
			void deleteTerminationRequest();

			/**
			 * @brief Resets the terminate bool to false.
			 *
			 * @return Returns the previous value of this variable.
			 */
			bool isTerminationRequested();
		private:
			osThreadId_t instance_;
			osThreadAttr_t attribs_;
			bool running_;
#ifdef STA_TACOS_WATCHDOG_ENABLED
			ThreadStatus status_;
#endif // STA_TACOS_WATCHDOG_ENABLED
#ifdef STA_CAN_BUS_ENABLE
			uint32_t canID_;
#endif // STA_TACOS_WATCHDOG_ENABLED
			bool terminate_;
			uint32_t previous_tick_;
		};
	}
}


#endif /* INCLUDE_TACOS_TASK_HPP_ */