package assigment5;
import java.util.Iterator;
import java.util.NoSuchElementException;

public class BinaryTreeInOrderIterator implements Iterator{
    private Stack stack;

    public BinaryTreeInOrderIterator(BinaryNode root)
    {
        stack = new StackAsDynamicArray();
        fillTheleft(root);
    }

    public boolean hasNext()
    {
        return (!(stack.isEmpty()));
    }
    public void fillTheleft(BinaryNode current)
    {
        while (current != null )
        {
            stack.push(current);
            current = current.left;
        }
    }

    public Object next()
    {
        if(!hasNext())
            throw new NoSuchElementException();

        BinaryNode current =  (BinaryNode) stack.pop();
        Object result = current.data;

        current = current.right;
        while(current != null) {
            stack.push(current);
            current = current.left;
        }

        return result;
    }

    public void remove() {
        throw new UnsupportedOperationException();
    }
}