<?php
/**
 * @package     Joomla.Platform
 * @subpackage  HTML
 *
 * @copyright   Copyright (C) 2005 - 2014 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 */

defined('JPATH_PLATFORM') or die;

/**
 * Pagination Class.  Provides a common interface for content pagination for the
 * Joomla! Platform.
 *
 * @package     Joomla.Platform
 * @subpackage  HTML
 * @since       11.1
 */
class JPagination extends JObject
{
   /**
    * @var    integer  The record number to start displaying from.
    * @since  11.1
    */
   public $limitstart = null;

   /**
    * @var    integer  Number of rows to display per page.
    * @since  11.1
    */
   public $limit = null;

   /**
    * @var    integer  Total number of rows.
    * @since  11.1
    */
   public $total = null;

   /**
    * @var    integer  Prefix used for request variables.
    * @since  11.1
    */
   public $prefix = null;

   /**
    * @var    boolean  View all flag
    * @since  11.1
    */
   protected $_viewall = false;

   /**
    * Additional URL parameters to be added to the pagination URLs generated by the class.  These
    * may be useful for filters and extra values when dealing with lists and GET requests.
    *
    * @var    array
    * @since  11.1
    */
   protected $_additionalUrlParams = array();

   /**
    * Constructor.
    *
    * @param   integer  $total       The total number of items.
    * @param   integer  $limitstart  The offset of the item to start at.
    * @param   integer  $limit       The number of items to display per page.
    * @param   string   $prefix      The prefix used for request variables.
    *
    * @since   11.1
    */
   public function __construct($total, $limitstart, $limit, $prefix = '')
   {
      // Value/type checking.
      $this->total = (int) $total;
      $this->limitstart = (int) max($limitstart, 0);
      $this->limit = (int) max($limit, 0);
      $this->prefix = $prefix;

      if ($this->limit > $this->total)
      {
         $this->limitstart = 0;
      }

      if (!$this->limit)
      {
         $this->limit = $total;
         $this->limitstart = 0;
      }

      /*
       * If limitstart is greater than total (i.e. we are asked to display records that don't exist)
       * then set limitstart to display the last natural page of results
       */
      if ($this->limitstart > $this->total - $this->limit)
      {
         $this->limitstart = max(0, (int) (ceil($this->total / $this->limit) - 1) * $this->limit);
      }

      // Set the total pages and current page values.
      if ($this->limit > 0)
      {
         $this->set('pages.total', ceil($this->total / $this->limit));
         $this->set('pages.current', ceil(($this->limitstart + 1) / $this->limit));
      }

      // Set the pagination iteration loop values.
      $displayedPages = 10;
      $this->set('pages.start', $this->get('pages.current') - ($displayedPages / 2));
      if ($this->get('pages.start') < 1)
      {
         $this->set('pages.start', 1);
      }
      if (($this->get('pages.start') + $displayedPages) > $this->get('pages.total'))
      {
         $this->set('pages.stop', $this->get('pages.total'));
         if ($this->get('pages.total') < $displayedPages)
         {
            $this->set('pages.start', 1);
         }
         else
         {
            $this->set('pages.start', $this->get('pages.total') - $displayedPages + 1);
         }
      }
      else
      {
         $this->set('pages.stop', ($this->get('pages.start') + $displayedPages - 1));
      }

      // If we are viewing all records set the view all flag to true.
      if ($limit == 0)
      {
         $this->_viewall = true;
      }
   }

   /**
    * Method to set an additional URL parameter to be added to all pagination class generated
    * links.
    *
    * @param   string  $key    The name of the URL parameter for which to set a value.
    * @param   mixed   $value  The value to set for the URL parameter.
    *
    * @return  mixed  The old value for the parameter.
    *
    * @since   11.1
    */
   public function setAdditionalUrlParam($key, $value)
   {
      // Get the old value to return and set the new one for the URL parameter.
      $result = isset($this->_additionalUrlParams[$key]) ? $this->_additionalUrlParams[$key] : null;

      // If the passed parameter value is null unset the parameter, otherwise set it to the given value.
      if ($value === null)
      {
         unset($this->_additionalUrlParams[$key]);
      }
      else
      {
         $this->_additionalUrlParams[$key] = $value;
      }

      return $result;
   }

   /**
    * Method to get an additional URL parameter (if it exists) to be added to
    * all pagination class generated links.
    *
    * @param   string  $key  The name of the URL parameter for which to get the value.
    *
    * @return  mixed  The value if it exists or null if it does not.
    *
    * @since   11.1
    */
   public function getAdditionalUrlParam($key)
   {
      $result = isset($this->_additionalUrlParams[$key]) ? $this->_additionalUrlParams[$key] : null;

      return $result;
   }

   /**
    * Return the rationalised offset for a row with a given index.
    *
    * @param   integer  $index  The row index
    *
    * @return  integer  Rationalised offset for a row with a given index.
    *
    * @since   11.1
    */
   public function getRowOffset($index)
   {
      return $index + 1 + $this->limitstart;
   }

   /**
    * Return the pagination data object, only creating it if it doesn't already exist.
    *
    * @return  object   Pagination data object.
    *
    * @since   11.1
    */
   public function getData()
   {
      static $data;
      if (!is_object($data))
      {
         $data = $this->_buildDataObject();
      }
      return $data;
   }

   /**
    * Create and return the pagination pages counter string, ie. Page 2 of 4.
    *
    * @return  string   Pagination pages counter string.
    *
    * @since   11.1
    */
   public function getPagesCounter()
   {
      // Initialise variables.
      $html = null;
      if ($this->get('pages.total') > 1)
      {
         $html .= JText::sprintf('JLIB_HTML_PAGE_CURRENT_OF_TOTAL', $this->get('pages.current'), $this->get('pages.total'));
      }
      return $html;
   }

   /**
    * Create and return the pagination result set counter string, e.g. Results 1-10 of 42
    *
    * @return  string   Pagination result set counter string.
    *
    * @since   11.1
    */
   public function getResultsCounter()
   {
      // Initialise variables.
      $html = null;
      $fromResult = $this->limitstart + 1;

      // If the limit is reached before the end of the list.
      if ($this->limitstart + $this->limit < $this->total)
      {
         $toResult = $this->limitstart + $this->limit;
      }
      else
      {
         $toResult = $this->total;
      }

      // If there are results found.
      if ($this->total > 0)
      {
         $msg = JText::sprintf('JLIB_HTML_RESULTS_OF', $fromResult, $toResult, $this->total);
         $html .= "\n" . $msg;
      }
      else
      {
         $html .= "\n" . JText::_('JLIB_HTML_NO_RECORDS_FOUND');
      }

      return $html;
   }

   /**
    * Create and return the pagination page list string, ie. Previous, Next, 1 2 3 ... x.
    *
    * @return  string  Pagination page list string.
    *
    * @since   11.1
    */
   public function getPagesLinks()
   {
      $app = JFactory::getApplication();

      // Build the page navigation list.
      $data = $this->_buildDataObject();

      $list = array();
      $list['prefix'] = $this->prefix;

      $itemOverride = false;
      $listOverride = false;

      $chromePath = JPATH_THEMES . '/' . $app->getTemplate() . '/html/pagination.php';
      if (file_exists($chromePath))
      {
         include_once $chromePath;
         if (function_exists('pagination_item_active') && function_exists('pagination_item_inactive'))
         {
            $itemOverride = true;
         }
         if (function_exists('pagination_list_render'))
         {
            $listOverride = true;
         }
      }

      // Build the select list
      if ($data->all->base !== null)
      {
         $list['all']['active'] = true;
         $list['all']['data'] = ($itemOverride) ? pagination_item_active($data->all) : $this->_item_active($data->all);
      }
      else
      {
         $list['all']['active'] = false;
         $list['all']['data'] = ($itemOverride) ? pagination_item_inactive($data->all) : $this->_item_inactive($data->all);
      }

      if ($data->start->base !== null)
      {
         $list['start']['active'] = true;
         $list['start']['data'] = ($itemOverride) ? pagination_item_active($data->start) : $this->_item_active($data->start);
      }
      else
      {
         $list['start']['active'] = false;
         $list['start']['data'] = ($itemOverride) ? pagination_item_inactive($data->start) : $this->_item_inactive($data->start);
      }
      if ($data->previous->base !== null)
      {
         $list['previous']['active'] = true;
         $list['previous']['data'] = ($itemOverride) ? pagination_item_active($data->previous) : $this->_item_active($data->previous);
      }
      else
      {
         $list['previous']['active'] = false;
         $list['previous']['data'] = ($itemOverride) ? pagination_item_inactive($data->previous) : $this->_item_inactive($data->previous);
      }

      $list['pages'] = array(); //make sure it exists
      foreach ($data->pages as $i => $page)
      {
         if ($page->base !== null)
         {
            $list['pages'][$i]['active'] = true;
            $list['pages'][$i]['data'] = ($itemOverride) ? pagination_item_active($page) : $this->_item_active($page);
         }
         else
         {
            $list['pages'][$i]['active'] = false;
            $list['pages'][$i]['data'] = ($itemOverride) ? pagination_item_inactive($page) : $this->_item_inactive($page);
         }
      }

      if ($data->next->base !== null)
      {
         $list['next']['active'] = true;
         $list['next']['data'] = ($itemOverride) ? pagination_item_active($data->next) : $this->_item_active($data->next);
      }
      else
      {
         $list['next']['active'] = false;
         $list['next']['data'] = ($itemOverride) ? pagination_item_inactive($data->next) : $this->_item_inactive($data->next);
      }

      if ($data->end->base !== null)
      {
         $list['end']['active'] = true;
         $list['end']['data'] = ($itemOverride) ? pagination_item_active($data->end) : $this->_item_active($data->end);
      }
      else
      {
         $list['end']['active'] = false;
         $list['end']['data'] = ($itemOverride) ? pagination_item_inactive($data->end) : $this->_item_inactive($data->end);
      }

      if ($this->total > $this->limit)
      {
         return ($listOverride) ? pagination_list_render($list) : $this->_list_render($list);
      }
      else
      {
         return '';
      }
   }

   /**
    * Return the pagination footer.
    *
    * @return  string   Pagination footer.
    *
    * @since   11.1
    */
   public function getListFooter()
   {
      $app = JFactory::getApplication();

      $list = array();
      $list['prefix'] = $this->prefix;
      $list['limit'] = $this->limit;
      $list['limitstart'] = $this->limitstart;
      $list['total'] = $this->total;
      $list['limitfield'] = $this->getLimitBox();
      $list['pagescounter'] = $this->getPagesCounter();
      $list['pageslinks'] = $this->getPagesLinks();

      $chromePath = JPATH_THEMES . '/' . $app->getTemplate() . '/html/pagination.php';
      if (file_exists($chromePath))
      {
         include_once $chromePath;
         if (function_exists('pagination_list_footer'))
         {
            return pagination_list_footer($list);
         }
      }
      return $this->_list_footer($list);
   }

   /**
    * Creates a dropdown box for selecting how many records to show per page.
    *
    * @return  string  The HTML for the limit # input box.
    *
    * @since   11.1
    */
   public function getLimitBox()
   {
      $app = JFactory::getApplication();

      // Initialise variables.
      $limits = array();

      // Make the option list.
      for ($i = 5; $i <= 30; $i += 5)
      {
         $limits[] = JHtml::_('select.option', "$i");
      }
      $limits[] = JHtml::_('select.option', '50', JText::_('J50'));
      $limits[] = JHtml::_('select.option', '100', JText::_('J100'));
      $limits[] = JHtml::_('select.option', '0', JText::_('JALL'));

      $selected = $this->_viewall ? 0 : $this->limit;

      // Build the select list.
      if ($app->isAdmin())
      {
         $html = JHtml::_(
            'select.genericlist',
            $limits,
            $this->prefix . 'limit',
            'class="inputbox" size="1" onchange="Joomla.submitform();"',
            'value',
            'text',
            $selected
         );
      }
      else
      {
         $html = JHtml::_(
            'select.genericlist',
            $limits,
            $this->prefix . 'limit',
            'class="inputbox" size="1" onchange="this.form.submit()"',
            'value',
            'text',
            $selected
         );
      }
      return $html;
   }

   /**
    * Return the icon to move an item UP.
    *
    * @param   integer  $i          The row index.
    * @param   boolean  $condition  True to show the icon.
    * @param   string   $task       The task to fire.
    * @param   string   $alt        The image alternative text string.
    * @param   boolean  $enabled    An optional setting for access control on the action.
    * @param   string   $checkbox   An optional prefix for checkboxes.
    *
    * @return  string   Either the icon to move an item up or a space.
    *
    * @since   11.1
    */
   public function orderUpIcon($i, $condition = true, $task = 'orderup', $alt = 'JLIB_HTML_MOVE_UP', $enabled = true, $checkbox = 'cb')
   {
      if (($i > 0 || ($i + $this->limitstart > 0)) && $condition)
      {
         return JHtml::_('jgrid.orderUp', $i, $task, '', $alt, $enabled, $checkbox);
      }
      else
      {
         return '&#160;';
      }
   }

   /**
    * Return the icon to move an item DOWN.
    *
    * @param   integer  $i          The row index.
    * @param   integer  $n          The number of items in the list.
    * @param   boolean  $condition  True to show the icon.
    * @param   string   $task       The task to fire.
    * @param   string   $alt        The image alternative text string.
    * @param   boolean  $enabled    An optional setting for access control on the action.
    * @param   string   $checkbox   An optional prefix for checkboxes.
    *
    * @return  string   Either the icon to move an item down or a space.
    *
    * @since   11.1
    */
   public function orderDownIcon($i, $n, $condition = true, $task = 'orderdown', $alt = 'JLIB_HTML_MOVE_DOWN', $enabled = true, $checkbox = 'cb')
   {
      if (($i < $n - 1 || $i + $this->limitstart < $this->total - 1) && $condition)
      {
         return JHtml::_('jgrid.orderDown', $i, $task, '', $alt, $enabled, $checkbox);
      }
      else
      {
         return '&#160;';
      }
   }

   /**
    * Create the HTML for a list footer
    *
    * @param   array  $list  Pagination list data structure.
    *
    * @return  string  HTML for a list footer
    *
    * @since   11.1
    */
   protected function _list_footer($list)
   {
      $html = "<div class=\"list-footer\">\n";

      $html .= "\n<div class=\"limit\">" . JText::_('JGLOBAL_DISPLAY_NUM') . $list['limitfield'] . "</div>";
      $html .= $list['pageslinks'];
      $html .= "\n<div class=\"counter\">" . $list['pagescounter'] . "</div>";

      $html .= "\n<input type=\"hidden\" name=\"" . $list['prefix'] . "limitstart\" value=\"" . $list['limitstart'] . "\" />";
      $html .= "\n</div>";

      return $html;
   }

   /**
    * Create the html for a list footer
    *
    * @param   array  $list  Pagination list data structure.
    *
    * @return  string  HTML for a list start, previous, next,end
    *
    * @since   11.1
    */
   protected function _list_render($list)
   {
      // Reverse output rendering for right-to-left display.
      $html = '<ul>';
      $html .= '<li class="pagination-start">' . $list['start']['data'] . '</li>';
      $html .= '<li class="pagination-prev">' . $list['previous']['data'] . '</li>';
      foreach ($list['pages'] as $page)
      {
         $html .= '<li>' . $page['data'] . '</li>';
      }
      $html .= '<li class="pagination-next">' . $list['next']['data'] . '</li>';
      $html .= '<li class="pagination-end">' . $list['end']['data'] . '</li>';
      $html .= '</ul>';

      return $html;
   }

   /**
    * Method to create an active pagination link to the item
    *
    * @param   JPaginationObject  &$item  The object with which to make an active link.
    *
    * @return   string  HTML link
    *
    * @since    11.1
    */
   protected function _item_active(&$item)
   {
      $app = JFactory::getApplication();
      if ($app->isAdmin())
      {
         if ($item->base > 0)
         {
            return "<a title=\"" . $item->text . "\" onclick=\"document.adminForm." . $this->prefix . "limitstart.value=" . $item->base
               . "; Joomla.submitform();return false;\">" . $item->text . "</a>";
         }
         else
         {
            return "<a title=\"" . $item->text . "\" onclick=\"document.adminForm." . $this->prefix
               . "limitstart.value=0; Joomla.submitform();return false;\">" . $item->text . "</a>";
         }
      }
      else
      {
         return "<a title=\"" . $item->text . "\" href=\"" . $item->link . "\" class=\"pagenav\">" . $item->text . "</a>";
      }
   }

   /**
    * Method to create an inactive pagination string
    *
    * @param   object  &$item  The item to be processed
    *
    * @return  string
    *
    * @since   11.1
    */
   protected function _item_inactive(&$item)
   {
      $app = JFactory::getApplication();
      if ($app->isAdmin())
      {
         return "<span>" . $item->text . "</span>";
      }
      else
      {
         return "<span class=\"pagenav\">" . $item->text . "</span>";
      }
   }

   /**
    * Create and return the pagination data object.
    *
    * @return  object  Pagination data object.
    *
    * @since   11.1
    */
   protected function _buildDataObject()
   {
      // Initialise variables.
      $data = new stdClass;

      // Build the additional URL parameters string.
      $params = '';
      if (!empty($this->_additionalUrlParams))
      {
         foreach ($this->_additionalUrlParams as $key => $value)
         {
            $params .= '&' . $key . '=' . $value;
         }
      }

      $data->all = new JPaginationObject(JText::_('JLIB_HTML_VIEW_ALL'), $this->prefix);
      if (!$this->_viewall)
      {
         $data->all->base = '0';
         $data->all->link = JRoute::_($params . '&' . $this->prefix . 'limitstart=');
      }

      // Set the start and previous data objects.
      $data->start = new JPaginationObject(JText::_('JLIB_HTML_START'), $this->prefix);
      $data->previous = new JPaginationObject(JText::_('JPREV'), $this->prefix);

      if ($this->get('pages.current') > 1)
      {
         $page = ($this->get('pages.current') - 2) * $this->limit;

         // Set the empty for removal from route
         //$page = $page == 0 ? '' : $page;

         $data->start->base = '0';
         $data->start->link = JRoute::_($params . '&' . $this->prefix . 'limitstart=0');
         $data->previous->base = $page;
         $data->previous->link = JRoute::_($params . '&' . $this->prefix . 'limitstart=' . $page);
      }

      // Set the next and end data objects.
      $data->next = new JPaginationObject(JText::_('JNEXT'), $this->prefix);
      $data->end = new JPaginationObject(JText::_('JLIB_HTML_END'), $this->prefix);

      if ($this->get('pages.current') < $this->get('pages.total'))
      {
         $next = $this->get('pages.current') * $this->limit;
         $end = ($this->get('pages.total') - 1) * $this->limit;

         $data->next->base = $next;
         $data->next->link = JRoute::_($params . '&' . $this->prefix . 'limitstart=' . $next);
         $data->end->base = $end;
         $data->end->link = JRoute::_($params . '&' . $this->prefix . 'limitstart=' . $end);
      }

      $data->pages = array();
      $stop = $this->get('pages.stop');
      for ($i = $this->get('pages.start'); $i <= $stop; $i++)
      {
         $offset = ($i - 1) * $this->limit;
         // Set the empty for removal from route
         //$offset = $offset == 0 ? '' : $offset;

         $data->pages[$i] = new JPaginationObject($i, $this->prefix);
         if ($i != $this->get('pages.current') || $this->_viewall)
         {
            $data->pages[$i]->base = $offset;
            $data->pages[$i]->link = JRoute::_($params . '&' . $this->prefix . 'limitstart=' . $offset);
         }
      }
      return $data;
   }
}

/**
 * Pagination object representing a particular item in the pagination lists.
 *
 * @package     Joomla.Platform
 * @subpackage  HTML
 * @since       11.1
 */
class JPaginationObject extends JObject
{
   /**
    * @var    string  The link text.
    * @since  11.1
    */
   public $text;

   /**
    * @var    integer  The number of rows as a base offset.
    * @since  11.1
    */
   public $base;

   /**
    * @var    string  The link URL.
    * @since  11.1
    */
   public $link;

   /**
    * @var    integer  The prefix used for request variables.
    * @since  11.1
    */
   public $prefix;

   /**
    * Class constructor.
    *
    * @param   string   $text    The link text.
    * @param   integer  $prefix  The prefix used for request variables.
    * @param   integer  $base    The number of rows as a base offset.
    * @param   string   $link    The link URL.
    *
    * @since   11.1
    */
   public function __construct($text, $prefix = '', $base = null, $link = null)
   {
      $this->text = $text;
      $this->prefix = $prefix;
      $this->base = $base;
      $this->link = $link;
   }
}