<?php
// +-----------------------------------------------------------------------+
// | This file is part of Piwigo.                                          |
// |                                                                       |
// | For copyright and license information, please view the COPYING.txt    |
// | file that was distributed with this source code.                      |
// +-----------------------------------------------------------------------+

/**
 * @package functions\calendar
 */

/** level of year view */
define('CYEAR', 0);
/** level of week view in weekly view */
define('CWEEK', 1);
/** level of month view in monthly view */
define('CMONTH', 1);
/** level of day view */
define('CDAY',  2);

/**
 * Base class for monthly and weekly calendar styles
 */
abstract class CalendarBase
{
  /** db column on which this calendar works */
  var $date_field;
  /** used for queries (INNER JOIN or normal) */
  var $inner_sql;
  /** used to store db fields */
  var $calendar_levels;

  /**
   * Generate navigation bars for category page.
   *
   * @return boolean false indicates that thumbnails where not included
   */
  abstract function generate_category_content();

  /**
   * Returns a sql WHERE subquery for the date field.
   *
   * @param int $max_levels (e.g. 2=only year and month)
   * @return string
   */
  abstract function get_date_where($max_levels=3);

  /**
   * Initialize the calendar.
   *
   * @param string $inner_sql
   */
  function initialize($inner_sql)
  {
    global $page;
    if ($page['chronology_field']=='posted')
    {
      $this->date_field = 'date_available';
    }
    else
    {
      $this->date_field = 'date_creation';
    }
    $this->inner_sql = $inner_sql;
  }

  /**
   * Returns the calendar title (with HTML).
   *
   * @return string
   */
  function get_display_name()
  {
    global $conf, $page;
    $res = '';

    for ($i=0; $i<count($page['chronology_date']); $i++)
    {
      $res .= $conf['level_separator'];
      if ( isset($page['chronology_date'][$i+1]) )
      {
        $chronology_date = array_slice($page['chronology_date'],0, $i+1);
        $url = duplicate_index_url(
            array( 'chronology_date'=>$chronology_date ),
            array( 'start' )
            );
        $res .=
          '<a href="'.$url.'">'
          .$this->get_date_component_label($i, $page['chronology_date'][$i])
          .'</a>';
      }
      else
      {
        $res .=
          '<span class="calInHere">'
          .$this->get_date_component_label($i, $page['chronology_date'][$i])
          .'</span>';
      }
    }
    return $res;
  }

  /**
   * Returns a display name for a date component optionally using labels.
   *
   * @return string
   */
  protected function get_date_component_label($level, $date_component)
  {
    $label = $date_component;
    if (isset($this->calendar_levels[$level]['labels'][$date_component]))
    {
      $label = $this->calendar_levels[$level]['labels'][$date_component];
    }
    elseif ('any' === $date_component )
    {
      $label = l10n('All');
    }
    return $label;
  }

  /**
   * Gets a nice display name for a date to be shown in previous/next links
   *
   * @param string $date
   * @return string
   */
  protected function get_date_nice_name($date)
  {
    $date_components = explode('-', $date);
    $res = '';
    for ($i=count($date_components)-1; $i>=0; $i--)
    {
      if ('any' !== $date_components[$i])
      {
        $label = $this->get_date_component_label($i, $date_components[$i] );
        if ( $res!='' )
        {
          $res .= ' ';
        }
        $res .= $label;
      }
    }
    return $res;
  }

  /**
   * Creates a calendar navigation bar.
   *
   * @param array $date_components
   * @param array $items - hash of items to put in the bar (e.g. 2005,2006)
   * @param bool $show_any - adds any link to the end of the bar
   * @param bool $show_empty - shows all labels even those without items
   * @param array $labels - optional labels for items (e.g. Jan,Feb,...)
   * @return string
   */
  protected function get_nav_bar_from_items($date_components, $items,
                                  $show_any,
                                  $show_empty=false, $labels=null)
  {
    global $conf, $page, $template;

    $nav_bar_datas=array();

    if ($conf['calendar_show_empty'] and $show_empty and !empty($labels) )
    {
      foreach ($labels as $item => $label)
      {
        if ( ! isset($items[$item]) )
        {
          $items[$item] = -1;
        }
      }
      ksort($items);
    }

    foreach ($items as $item => $nb_images)
    {
      $label = $item;
      if (isset($labels[$item]))
      {
        $label = $labels[$item];
      }
      if ($nb_images==-1)
      {
        $tmp_datas=array(
          'LABEL'=> $label
        );
      }
      else
      {
        $url = duplicate_index_url(
          array('chronology_date'=>array_merge($date_components,array($item))),
          array( 'start' )
            );
        $tmp_datas=array(
          'LABEL'=> $label,
          'URL' => $url
        );
      }
      if ($nb_images > 0)
      {
        $tmp_datas['NB_IMAGES']=$nb_images;
      }
      $nav_bar_datas[]=$tmp_datas;

    }

    if ($conf['calendar_show_any'] and $show_any and count($items)>1 and
          count($date_components)<count($this->calendar_levels)-1 )
    {
      $url = duplicate_index_url(
        array('chronology_date'=>array_merge($date_components,array('any'))),
        array( 'start' )
          );
      $nav_bar_datas[]=array(
        'LABEL' => l10n('All'),
        'URL' => $url
      );
    }

    return $nav_bar_datas;
  }

  /**
   * Creates a calendar navigation bar for a given level.
   *
   * @param int $level - 0-year, 1-month/week, 2-day
   */
  protected function build_nav_bar($level, $labels=null)
  {
    global $template, $conf, $page;

    $query = '
SELECT DISTINCT('.$this->calendar_levels[$level]['sql'].') as period,
  COUNT(DISTINCT id) as nb_images'.
$this->inner_sql.
$this->get_date_where($level).'
  GROUP BY period;';

    $level_items = query2array($query, 'period', 'nb_images');

    if ( count($level_items)==1 and
         count($page['chronology_date'])<count($this->calendar_levels)-1)
    {
      if ( ! isset($page['chronology_date'][$level]) )
      {
        list($key) = array_keys($level_items);
        $page['chronology_date'][$level] = (int)$key;

        if ( $level<count($page['chronology_date']) and
             $level!=count($this->calendar_levels)-1 )
        {
          return;
        }
      }
    }

    $dates = $page['chronology_date'];
    while ($level<count($dates))
    {
      array_pop($dates);
    }

    $nav_bar = $this->get_nav_bar_from_items(
      $dates,
      $level_items,
      true,
      true,
      isset($labels) ? $labels : $this->calendar_levels[$level]['labels']
      );

    $template->append(
      'chronology_navigation_bars',
      array(
        'items' => $nav_bar,
        )
      );
  }

  /**
   * Assigns the next/previous link to the template with regards to
   * the currently choosen date.
   */
  protected function build_next_prev()
  {
    global $template, $page;

    $prev = $next =null;
    if ( empty($page['chronology_date']) )
      return;
    
    $sub_queries = array();
    $nb_elements = count($page['chronology_date']);
    for ($i=0; $i<$nb_elements; $i++)
    {
      if ( 'any' === $page['chronology_date'][$i] )
      {
        $sub_queries[] = '\'any\'';
      }
      else
      {
        $sub_queries[] = pwg_db_cast_to_text($this->calendar_levels[$i]['sql']);
      }
    }
    $query = 'SELECT '.pwg_db_concat_ws($sub_queries, '-').' AS period';
    $query .= $this->inner_sql .'
AND ' . $this->date_field . ' IS NOT NULL
GROUP BY period';
    
    $current = implode('-', $page['chronology_date'] );
    $upper_items = query2array($query,null, 'period');

    usort($upper_items, 'version_compare');
    $upper_items_rank = array_flip($upper_items);
    if ( !isset($upper_items_rank[$current]) )
    {
      $upper_items[] = $current;// just in case (external link)
      usort($upper_items, 'version_compare');
      $upper_items_rank = array_flip($upper_items);
    }
    $current_rank = $upper_items_rank[$current];

    $tpl_var = array();

    if ( $current_rank>0 )
    { // has previous
      $prev = $upper_items[$current_rank-1];
      $chronology_date = explode('-', $prev);
      $tpl_var['previous'] =
        array(
          'LABEL' => $this->get_date_nice_name($prev),
          'URL' => duplicate_index_url(
                array('chronology_date'=>$chronology_date), array('start')
                )
        );
    }

    if ( $current_rank < count($upper_items)-1 )
    { // has next
      $next = $upper_items[$current_rank+1];
      $chronology_date = explode('-', $next);
      $tpl_var['next'] =
        array(
          'LABEL' => $this->get_date_nice_name($next),
          'URL' => duplicate_index_url(
                array('chronology_date'=>$chronology_date), array('start')
                )
        );
    }

    if ( !empty($tpl_var) )
    {
      $existing = $template->smarty->getVariable('chronology_navigation_bars');
      if (! ($existing instanceof Smarty_Undefined_Variable))
      {
        $existing->value[ sizeof($existing->value)-1 ] =
          array_merge( $existing->value[ sizeof($existing->value)-1 ], $tpl_var);
      }
      else
      {
        $template->append( 'chronology_navigation_bars', $tpl_var );
      }
    }
  }
}

?>