#include "myList.h"

void List::add(Object &newNode)
{
	Node *newElement = new Node(&newNode);

	if(head != 0)//if there is already a node just add item to head of list
	{
		newElement->next = head;
		head = newElement;
		noEntries++;
	}
	else//there is only one entry therefore head and tail point to the same place
	{
		newElement->next = head;
		head = newElement;
		tail = newElement;
		noEntries++;
	}
}

void List::push_back(Object &newNode)
{
	Node *newElement = new Node(&newNode);

	if(head != 0)
	{
		tail->next = newElement;
		tail = newElement;
		noEntries++;
	}
	else
	{
		tail = newElement;
		head = newElement;
		noEntries++;
	}
}

//start at the head of the list
//delete items as you move along
//stop when at the end i.e. when
//the next pointer value is 0
List::~List()
{
	while(head!=0)
	{
		Node *temp = head;
		head = head->next;
		delete temp;	//delete what temp points at!
	}
}

Object &List::at(int index)
{
	Node *temp = head;
	int i;
	for(i = 0; i < index; ++i)
	{
		temp = temp->next;
	}

	return &temp->info;
}

int List::size()
{
	int i = 0;
	Node *temp = head;

	while(temp != tail)
	{
		++i;
	}
	return i;
}

void List::erase(int index)
{
	Node *temp = at(index);
	delete temp;
	//Might actually need to use the destructor at this point in which case it would be
	//something like ~Node(temp); where that deletes all variables and references relating to temp
}

//Tell each item in the list to print itself
//start at the front i.e. at the head of the list
ostream &List::print(ostream &co)
{
	Node *temp = head;			//point wherever head is pointing (head always points to current first element)
	while (temp!=0)				//while there are actually elements int the list
	{
		temp->info->printOn(co);//info is a pointer to the the first element in the list (the list itself). Call printOn for that list
		temp = temp->next; //printOn is a friend of linked list and therefore friend to all other classes used in LinkedList.h
	}
	return co; //ostream used is cout therefore return type returns a reference to an ostream in this case returning cout
}

ostream &List::printAt(ostream &co, int index)
{
	Node *temp = at(index);
	temp->info->printOn(co);

	return co;
}