<?php
	class pagesystem implements ioptPagesystem
	{
		private $buffer;		// the buffer, where the page information is generated to.
		private $prev;			// the number of the previously returned page

		// some other class methods here...

		/*
	 	 * Returns the next page from the buffer or nothing, if the script reaches the end of the buffer.
		 */
		public function getPage()
		{
			if(!is_array($this -> buffer))
			{
				$this -> prepare(); // generate the list of pages, if it does not exist
			}
			$page = key($this -> buffer); // try to get the next page
			if(!is_null($page))
			{
				if($this -> prev + 1 != $page) // there is a hole in the page numbers, insert the separator here.
				{
					$this -> prev = $page - 1;
					return array('t' => 2, 'p' => 0, 'l' => '');
				}

				$this -> prev = $page;
				next($this->buffer); // jump to the next page
				return array('t' => ($page == $this->from_pos ? 1 : 0), // return the page, checking whether it's the active one
					'p' => $page,
					'l' => $this -> l($page)
				);
			}
		} // end getPage();

		/*
	 	 * Returns the information for the "next page" link.
		 */
		public function nextPage()
		{
			if($this -> from_pos < $this -> pages)
			{
				return array('t' => 0, 'p' => $this->from_pos+1, 'l' => $this->l($this->from_pos+1));
			}
		} // end nextPage();

		/*
		 * Returns the information for the "previous page" link.
		 */
		public function prevPage()
		{
			if($this -> from_pos > 1)
			{
				return array('t' => 0, 'p' => $this->from_pos-1, 'l' => $this->l($this->from_pos-1));
			}
		} // end prevPage();

		/*
		 * Returns the information for the "first page" link.
		 */
		public function firstPage()
		{
			if($this -> pages > 1)
			{
				return array('t' => 0, 'p' => 1, 'l' => $this->l(1));
			}
		} // end firstPage();

		/*
		 * Returns the information for the "last page" link.
		 */
		public function lastPage()
		{
			if($this -> pages > 1)
			{
				return array('t' => 0, 'p' => $this->pages, 'l' => $this->l($this->pages));
			}
		} // end lastPage();
	}
?>