eventQueue.cpp

/*
 * PA4_the_murder - Jacob Tutlis - jjtutlis - James Taylor - jrtaylor
 * Created by jrtaylor on 2/11/18.
 */

#include "eventQueue.h"
#include "event.h"

event *eventQueue::getFirst() {
    return head->data;
}

/**
 * for getting an event at the given index
 * @param index
 * @return
 */
event *eventQueue::getIndex(int index) {
    node *cur = new node;
    cur = head;
    for (int i = 0; i < index; ++i) {
        cur = cur->next;
    }
    return cur->data;
}

/*
 * creates a new event node
 * @param event new event
 * @return void
 */
void eventQueue::createNode(event *e) {
	node *temp = new node;
	temp->data = e;
	temp->next = NULL;
	if (head == NULL) {
		head = temp;
		tail = temp;
		temp = NULL;
	} else {
		tail->next = temp;
		tail = temp;
	}
}

/* displays all the nodes in linked list
 * @return void
 */
void eventQueue::display() {
	node *temp;
	temp = new node;
	temp = head;
	while (temp != NULL) {
		cout << temp->data->getArrTime() << "\t";
		temp = temp->next;
	}
}

/* adds event to the start of the linked list
 * @param value event being added
 * @return void
 */
void eventQueue::insert_start(event *value) {
	node *temp;
	temp = new node;
	temp->data = value;
	temp->next = head;
	head = temp;
}

/* adds event to the correct position of the linked list
 * @param value event being added
 * @return void
 */
void eventQueue::priorityAdd(event *value) {

	node *temp, *temp1, *temp2;
	temp = new node;
    temp1 = new node;
    temp2 = new node;
	temp->data = value;
	temp->arrTime = value->getArrTime(); // Priority
	if (head == NULL || value->getArrTime() < head->arrTime) {
		temp->next = head;
		head = temp;
	} else {
		temp1 = head;
		//q->link->priority <= priority)
        // TODO: Solve infinite loop here
		while (temp1->next != NULL && temp1->data->getArrTime() <= value->getArrTime()) {
            // checks if the input value's time is less than the next and greater than the previous
            if(temp->data->getArrTime() >= temp1->data->getArrTime()){
                // path for setting a new tail
                if(temp1->next == NULL){
                    temp->next = NULL;
                    temp1->next = temp;
                    tail = temp;
                }
                // path for inserting within the list
                else{
                    temp2 = temp1->next;
                    temp->next = temp2;
                    temp1->next = temp;
                }
                break;
            }
			temp1 = temp1->next;
			temp->next = temp1->next;
			temp1->next = temp;
		}
	}

}

/* adds event to a certain position of the linked list
 * @param pos desired pos to be added
 * @param value event being added
 * @return void
 */
void eventQueue::insert_position(int pos, event *value) {
	node *pre;
	node *cur;
	node *temp;
	pre = new node;
	cur = new node;
	temp = new node;
	cur = head;
	for (int i = 1; i < pos; ++i) {
		pre = cur;
		cur = cur->next;
	}
	temp->data = value;
	pre->next = temp;
	temp->next = cur;
}

/* removes head of the linked list
 * @return void
 */
void eventQueue::delete_first() {
	node *temp;
	temp = head;
	head = head->next;
	delete temp;
}