package Examples;

import java.util.*;
import java.util.logging.Logger;

import Sequenic.T3.SuiteUtils.Inference.Comment;

public class PriorityQueue {
	
	private static class Node {
		Comparable value ;
		Node next = null ;
		Node(Comparable x) { value = x ; }
		Node linkto(Node n) { next = n ; return this ; }
	} 
	
	private Node stack = null ;
	private int size = 0 ;
	
	private final static Comment comment = new Comment(Logger.getLogger(PriorityQueue.class.getName())) ; 

	// public int size() { return stack.size() ; }

	private Node insert(Node n, Comparable x) {
		Node x_ = new Node(x) ;
		x_.linkto(n.next) ;
		n.next = x_ ;
		size++ ;
		return n ;
	}
	
	
	public Comparable put(Comparable x) {
		if (x == null) throw new IllegalArgumentException() ;
		comment.with("input ok").end() ;
		if (size == 0) {
			comment.with("found an empty stack").end(); ;
			stack = new Node(x) ; size++ ;
			return x ;
		}
		
		comment.with("singleton").If(size==1);
		
		if (stack.value.compareTo(x)>0) {
			comment.with("inserting at the head").end(); ;
			stack = new Node(x) . linkto(stack) ; size++ ;
			return x ;
		}
		
		Node p = stack ;
		while (true) {
		   if (p.value.compareTo(x) == 0) {
			   comment.with("x is already in the queue").end(); 
			   return null ;
		   }
		   if (p.next == null || p.next.value.compareTo(x) > 0) {
			   comment.with("inserting x...").end();   
			   insert(p,x) ;
			   return x ;			   
		   }
		   p = p.next ;
		}
	}
	
	public Integer indexOf(Comparable x) {
		int toGo = size ;
		Node p = stack ;
		while (toGo>0) {
			if (p.value.compareTo(x) == 0) return size - toGo ;
			toGo-- ;
			p = p.next ;
		}
		return null ;
	}

	public static void main(String[] args) {
		PriorityQueue q = new PriorityQueue() ;
		q.put(1) ; q.put(10) ; q.put(3) ; q.put(1) ; q.put(3) ; q.put(10) ; q.put(-1) ; q.put(11) ;
		Node p = q.stack ;
		while (p != null) {
			System.out.println(">> " + p.value) ;
			p = p.next ;
		}
		System.out.println(">> size " + q.size) ;
	}
	
}