--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/includes/tablesort.inc	Tue Dec 23 14:28:28 2008 +0100
@@ -0,0 +1,200 @@
+<?php
+// $Id: tablesort.inc,v 1.47 2008/01/04 09:31:48 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'), 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';
+}