Scheduler.cpp

/** A Scheduler schedules iterative commands to be run, and then executes them
  * in order.  Commands can be added, and removed, can be scheduled to run in parallel
  * with other commands, and can be scheduled to run persistently.  Credits to PeterMitrano
  * for some of the initial code
  * @author Jordan Burklund
  * @version 1.0
  * @date Sept. 2015
  **/

#include "Scheduler.h"

Scheduler* Scheduler::instance = NULL;

/** Constructor **/
Scheduler::Scheduler() {
}

/** Get the singleton instance of the scheduler
  * @return The instance of the scheduler
  **/
Scheduler* Scheduler::getInstance() {
	if(instance == NULL) {
		instance = new Scheduler();
	}
	return instance;
}

/** Adds a command to the end of the scheduled
  * list of commands, and does change the parallel flag
  * @param command Pointer to the command to add
  **/
void Scheduler::addCommand(Command* command) {
	/* #TODO Should we prevent scheduling the same command?
	if(!commands.contains(command)) {
		commands.add(command);
	} */
	commands.add(command);
}

/** Adds a command to the end of the scheduled list, and sets
  * the flag to run in parallel
  * @param command Pointer to the command to add
  * @note this may change soon with command groups
  **/
void Scheduler::addParallelCommand(Command* command) {
	command->setParallel(true);
	commands.add(command);
}

/** Adds a command to the end of the scheduled list, and sets 
  * the flag to not run in parallel
  * @param command Pointer to the command to add
  * @note this may change soon with command groups
  **/
void Scheduler::addSequentialCommand(Command* command) {
	command->setParallel(false);
	commands.add(command);
}

/** Execute an iteration of the scheduled commands
  **/
void Scheduler::run() {
	//Execute commands until there is a command that is not parallel
	int size = commands.size();

	Command* command;
	bool isFinished;
	int i = 0;
	while(i<size) {
		//Get the command
		command = commands.get(i);
		isFinished = command->cycle();
		//Remove the command if it is finished
		if(isFinished) {
			commands.remove(i);
			size = commands.size();
			if(command->isParallel()) {
				//don't increment, since just removed
			} else {
				//command was sequential, done with this loop
				break;
			}
		} else {
			if(command->isParallel()) {
				//Command is parallel, increment the pointer
				i++;
			} else {
				//Command is sequential, done with this loop
				break;
			}
		}
	}
	
}


/** Print out the current list of scheduled commands
  **/
void Scheduler::printCommands() {
	if(commands.size() > 0) {
		for(int i=0, n=commands.size(); i<n; i++) {
			Serial.println(commands.get(i)->name);
		}
	} else {
		Serial.println("Scheduler: No Commands Scheduled");
	}
}