// Airport.cpp : definitions of the Airport class functions

#include <stdlib.h>

#include "Airport.h"
#include "Controller.h"
#include "Event.h"
#include "utils.h"

Airport::Airport(GP142Display *display) {
	// initialize the screen on which the airport will be displayed
	this->display = display;		

	// initialize the number of runways equal to zero
	numRunways = 0;
	for (int i = 0; i < MAX_RUNWAYS; i++) {
		runways[i] = NULL;
	}

	// create an instance of the Controller
	airTrafficController = new Controller (this);
}


// This function invokes Controller::generateEvent 
// *** Note that the argument to getNextEvent is pass by reference 
// This argument in turn is passed to generateEvent, again by reference
// Controller::generateEvent sets the value of runwayNumber. Since
// both Airport::getNextEvent and Controller::generateEvent pass their
// argument by reference, this change gets reflected in the argument
// that was passed to getNextEvent ***
EventType Airport::getNextEvent (int &runwayNumber) {
	return airTrafficController->generateEvent (runwayNumber);
}


int Airport::getNumRunways () {
	return numRunways;
}


Runway* Airport::getRunway (int i) {
	if (i >= numRunways || i < 0)
		return NULL;		// return NULL if i-th runway does not exist
	
	return runways[i];	
}


bool Airport::addRunway (int y) {
	if (numRunways == MAX_RUNWAYS)	{
		// simply ignores if already MAX_RUNWAYS exist and returns false
		return false;		
	}

	runways[numRunways] = new Runway (y, display);
	numRunways++;

	return true;
}


void Airport::simulate () {
	Event *event;

	this->draw();			// draw the airport and the runway 

	for (int i = 0; i < numRunways; i++) {

		// for each runway, get the event that is in progress on it
		event = runways[i]->getEventInProgress();
		if (event == NULL) {
			// if no event is currently in progress on a runway, then
			// get an event from any one of the event queues associated with
			// the runway. The choice of the event queue can again be 
			// random.
			// *** The starter code has just one possible event. So the 
			// second argument to randomNumber is 1. When there two possible
			// events to choose from, then the argument to randomNumber will
			// be 2 ***
			int whatToDo = randomNumber (0,1);
			switch (whatToDo) {
			case 0:
				event = runways[i]->getTakeOffQueue()->dequeue();
				break;
			default:
				break;
			}
			
			// update the event in progress on the runway to the new event just
			// dequeued from the eventqueue
			runways[i]->setEventInProgress (event);
		}

		if (event != NULL) {
			// doEvent returns true if the event gets over. 
			bool retval = event->doEvent();
			event->draw();	// draw the event
			if (retval)	{	
				// if the event got over, mark it in the corresponding runway as over
				runways[i]->setEventOver();
			}
		}
	}
}


void Airport::draw () {
	// clear the display
	display->clear ();

	// draw the sky and the background
	display->drawRectangle (SKY_LEFTX, SKY_BOTTOMY, SKY_RIGHTX, SKY_TOPY, IceBlue, 0);
	display->drawRectangle (FIELD_LEFTX, FIELD_BOTTOMY, FIELD_RIGHTX, FIELD_TOPY, SeaGreen, 0);

	// draw the airport building : got to make some enhancements
	display->drawRectangle (BUILD1_LEFTX, BUILD1_BOTTOMY, BUILD1_RIGHTX, BUILD1_TOPY, Peach, 0);
	display->write (BUILD1_LEFTX, BUILD1_TOPY - TEXTHEIGHT, " Seattle Tacoma ", Black, TEXTHEIGHT);
	
	// draw each of the runways and stuff related with each runway
	for (int i = 0; i < numRunways; i++) {
		runways[i]->draw ();
	}
}


Airport::~Airport() {
	for (int i = 0; i < numRunways; i++) {
		delete runways[i];
	}

	delete airTrafficController;
}