<?php

// $Id: tablesort.inc,v 1.47.2.1 2009/07/01 20:51:55 goba Exp $

/**

 * @file

 * Functions to aid in the creation of sortable tables.

 *

 * All tables created with a call to theme('table') have the option of having

 * column headers that the user can click on to sort the table by that column.

 */

/**

 * Initialize the table sort context.

 */

function tablesort_init($header) {

  $ts = tablesort_get_order($header);

  $ts['sort'] = tablesort_get_sort($header);

  $ts['query_string'] = tablesort_get_querystring();

  return $ts;

}

/**

 * Create an SQL sort clause.

 *

 * This function produces the ORDER BY clause to insert in your SQL queries,

 * assuring that the returned database table rows match the sort order chosen

 * by the user.

 *

 * @param $header

 *   An array of column headers in the format described in theme_table().

 * @param $before

 *   An SQL string to insert after ORDER BY and before the table sorting code.

 *   Useful for sorting by important attributes like "sticky" first.

 * @return

 *   An SQL string to append to the end of a query.

 *

 * @ingroup database

 */

function tablesort_sql($header, $before = '') {

  $ts = tablesort_init($header);

  if ($ts['sql']) {

    // Based on code from db_escape_table(), but this can also contain a dot.

    $field = preg_replace('/[^A-Za-z0-9_.]+/', '', $ts['sql']);

    // Sort order can only be ASC or DESC.

    $sort = drupal_strtoupper($ts['sort']);

    $sort = in_array($sort, array('ASC', 'DESC')) ? $sort : '';

    return " ORDER BY $before $field $sort";

  }

}

/**

 * Format a column header.

 *

 * If the cell in question is the column header for the current sort criterion,

 * it gets special formatting. All possible sort criteria become links.

 *

 * @param $cell

 *   The cell to format.

 * @param $header

 *   An array of column headers in the format described in theme_table().

 * @param $ts

 *   The current table sort context as returned from tablesort_init().

 * @return

 *   A properly formatted cell, ready for _theme_table_cell().

 */

function tablesort_header($cell, $header, $ts) {

  // Special formatting for the currently sorted column header.

  if (is_array($cell) && isset($cell['field'])) {

    $title = t('sort by @s', array('@s' => $cell['data']));

    if ($cell['data'] == $ts['name']) {

      $ts['sort'] = (($ts['sort'] == 'asc') ? 'desc' : 'asc');

      if (isset($cell['class'])) {

        $cell['class'] .= ' active';

      }

      else {

        $cell['class'] = 'active';

      }

      $image = theme('tablesort_indicator', $ts['sort']);

    }

    else {

      // If the user clicks a different header, we want to sort ascending initially.

      $ts['sort'] = 'asc';

      $image = '';

    }

    if (!empty($ts['query_string'])) {

      $ts['query_string'] = '&'. $ts['query_string'];

    }

    $cell['data'] = l($cell['data'] . $image, $_GET['q'], array('attributes' => array('title' => $title), 'query' => 'sort='. $ts['sort'] .'&order='. urlencode($cell['data']) . $ts['query_string'], 'html' => TRUE));

    unset($cell['field'], $cell['sort']);

  }

  return $cell;

}

/**

 * Format a table cell.

 *

 * Adds a class attribute to all cells in the currently active column.

 *

 * @param $cell

 *   The cell to format.

 * @param $header

 *   An array of column headers in the format described in theme_table().

 * @param $ts

 *   The current table sort context as returned from tablesort_init().

 * @param $i

 *   The index of the cell's table column.

 * @return

 *   A properly formatted cell, ready for _theme_table_cell().

 */

function tablesort_cell($cell, $header, $ts, $i) {

  if (isset($header[$i]['data']) && $header[$i]['data'] == $ts['name'] && !empty($header[$i]['field'])) {

    if (is_array($cell)) {

      if (isset($cell['class'])) {

        $cell['class'] .= ' active';

      }

      else {

        $cell['class'] = 'active';

      }

    }

    else {

      $cell = array('data' => $cell, 'class' => 'active');

    }

  }

  return $cell;

}

/**

 * Compose a query string to append to table sorting requests.

 *

 * @return

 *   A query string that consists of all components of the current page request

 *   except for those pertaining to table sorting.

 */

function tablesort_get_querystring() {

  return drupal_query_string_encode($_REQUEST, array_merge(array('q', 'sort', 'order', 'pass'), array_keys($_COOKIE)));

}

/**

 * Determine the current sort criterion.

 *

 * @param $headers

 *   An array of column headers in the format described in theme_table().

 * @return

 *   An associative array describing the criterion, containing the keys:

 *   - "name": The localized title of the table column.

 *   - "sql": The name of the database field to sort on.

 */

function tablesort_get_order($headers) {

  $order = isset($_GET['order']) ? $_GET['order'] : '';

  foreach ($headers as $header) {

    if (isset($header['data']) && $order == $header['data']) {

      return array('name' => $header['data'], 'sql' => isset($header['field']) ? $header['field'] : '');

    }

    if (isset($header['sort']) && ($header['sort'] == 'asc' || $header['sort'] == 'desc')) {

      $default = array('name' => $header['data'], 'sql' => isset($header['field']) ? $header['field'] : '');

    }

  }

  if (isset($default)) {

    return $default;

  }

  else {

    // The first column specified is initial 'order by' field unless otherwise specified

    if (is_array($headers[0])) {

      $headers[0] += array('data' => NULL, 'field' => NULL);

      return array('name' => $headers[0]['data'], 'sql' => $headers[0]['field']);

    }

    else {

      return array('name' => $headers[0]);

    }

  }

}

/**

 * Determine the current sort direction.

 *

 * @param $headers

 *   An array of column headers in the format described in theme_table().

 * @return

 *   The current sort direction ("asc" or "desc").

 */

function tablesort_get_sort($headers) {

  if (isset($_GET['sort'])) {

    return ($_GET['sort'] == 'desc') ? 'desc' : 'asc';

  }

  // User has not specified a sort. Use default if specified; otherwise use "asc".

  else {

    foreach ($headers as $header) {

      if (is_array($header) && array_key_exists('sort', $header)) {

        return $header['sort'];

      }

    }

  }

  return 'asc';

}