exhibit.module

<?php
// $Id$

//////////////////////////////////////////////////////////////////////////////
// Module settings

define('EXHIBIT_DATE_FORMAT',        '%Y-%m-%dT%H:%M:%SZ');
define('EXHIBIT_XMLNS_URL',          'http://simile.mit.edu/2006/11/exhibit#');  // TODO:  What's this for? This needs to be updated or removed
define('EXHIBIT_JS_URL',             variable_get('exhibit_js_url', 'http://api.simile-widgets.org/exhibit/2.2.0/exhibit-api.js'));
define('EXHIBIT_MAP_JS_URL',         variable_get('exhibit_map_js_url', 'http://api.simile-widgets.org/exhibit/2.2.0/extensions/map/map-extension.js'));
define('EXHIBIT_BARCHART_JS_URL',    variable_get('exhibit_barchart_js_url', 'http://api.simile-widgets.org/exhibit/2.2.0/extensions/chart/chart-extension.js'));
define('EXHIBIT_SCATTERPLOT_JS_URL', variable_get('exhibit_scatterplot_js_url', 'http://api.simile-widgets.org/exhibit/2.2.0/extensions/chart/chart-extension.js'));
define('EXHIBIT_TIMELINE_JS_URL',    variable_get('exhibit_timeline_js_url', 'http://api.simile-widgets.org/exhibit/2.2.0/extensions/time/time-extension.js'));
define('EXHIBIT_CALENDAR_JS_URL',    variable_get('exhibit_calendar_js_url', 'http://api.simile-widgets.org/exhibit/2.2.0/extensions/calendar/calendar-extension.js'));
define('EXHIBIT_FEED_LIFETIME',      (int)variable_get('timeline_feed_lifetime', 0));
define('EXHIBIT_FEED_ETAG',          (bool)variable_get('timeline_feed_etag', TRUE));


//////////////////////////////////////////////////////////////////////////////
// Core API hooks

/**
 * Implementation of hook_help().
 */
function exhibit_help($path) {
  switch ($path) {
    case 'admin/help#exhibit':
      return '<p>' . t('') . '</p>'; // TODO
    case 'admin/settings/exhibit':
      //return '<p>' . t('') . '</p>'; // TODO
  }
}

/**
 * Implementation of hook_perm().
 */
function exhibit_perm() {
  return array(
    'administer exhibit feeds',
    //'use external exhibit feeds', // TODO
    'access exhibits',
    'create exhibits',
    'edit exhibits',
    'edit own exhibits',
    'delete exhibits',
    'delete own exhibits',
  );
}

/**
 * Implementation of hook_menu().
 */
function exhibit_menu() {
  return array(
    'node/%node/exhibit-json' => array(
      'type' => MENU_CALLBACK,
      'access callback' => 'user_access',
      'access arguments' => array('access exhibits'),
      'page callback' => 'exhibit_output_node',
      'page arguments' => array(1),
      'file' => 'exhibit.pages.inc',
    ),
    'node/__history__.html' => array(
      'type' => MENU_CALLBACK,
      'access arguments' => array('access exhibits'),
      'page callback' => 'exhibit_output_history',
      'file' => 'exhibit.pages.inc',
    ),
    'exhibit/tsv/%' => array(
      'type' => MENU_CALLBACK,
      'access arguments' => array('access exhibits'),
      'page callback' => 'exhibit_output_convert',
      'page arguments' => array(2, 'exhibit_parse_tsv', 'text/tab-separated-values'),
      'file' => 'exhibit.pages.inc',
    ),
    'exhibit/feeds/%exhibit_feed' => array(
      'type' => MENU_CALLBACK,
      'access arguments' => array('access exhibits'),
      'page callback' => 'exhibit_output_feed',
      'page arguments' => array(2),
      'file' => 'exhibit.pages.inc',
    ),
    'admin/settings/exhibit' => array(
      'title' => 'Exhibits',
      'description' => 'Settings for the Exhibit module.',
      'access arguments' => array('administer site configuration'),
      'page callback' => 'drupal_get_form',
      'page arguments' => array('exhibit_admin_settings'),
      'file' => 'exhibit.admin.inc',
    ),
    'admin/content/exhibit' => array(
      'title' => 'Exhibit feeds',
      'access arguments' => array('administer exhibit feeds'),
      'page callback' => 'exhibit_admin_feeds',
      'file' => 'exhibit.admin.inc',
    ),
    'admin/content/exhibit/list' => array(
      'title' => 'List',
      'type' => MENU_DEFAULT_LOCAL_TASK,
      'access arguments' => array('administer exhibit feeds'),
      'weight' => -10,
    ),
    'admin/content/exhibit/add' => array(
      'title' => 'Add data feed',
      'type' => MENU_LOCAL_TASK,
      'access arguments' => array('administer exhibit feeds'),
      'page callback' => 'drupal_get_form',
      'page arguments' => array('exhibit_admin_feed_form'),
      'file' => 'exhibit.admin.inc',
      'weight' => 10,
    ),
    'admin/content/exhibit/edit/%exhibit_feed' => array(
      'title' => 'Edit data feed',
      'type' => MENU_CALLBACK,
      'access arguments' => array('administer exhibit feeds'),
      'page callback' => 'drupal_get_form',
      'page arguments' => array('exhibit_admin_feed_form', 4),
      'file' => 'exhibit.admin.inc',
    ),
    'admin/content/exhibit/delete/%exhibit_feed' => array(
      'title' => 'Delete data feed',
      'type' => MENU_CALLBACK,
      'access arguments' => array('administer exhibit feeds'),
      'page callback' => 'drupal_get_form',
      'page arguments' => array('exhibit_admin_feed_delete', 4),
      'file' => 'exhibit.admin.inc',
    ),
  );
}

/**
 * Implementation of hook_block().
 */
function exhibit_block($op = 'list', $delta = 0, $edit = array()) {
  switch ($op) {
    case 'list':
      return array('facets' => array('info' => t('Exhibit facets')));
    case 'view':
      switch ($delta) {
        case 'facets':
          if (arg(0) == 'node' && is_numeric(arg(1)) && arg(2) != 'edit') {
            $node = node_load(arg(1));
            $block['content'] = $node->exhibit['facet_definition'];
          }
          break;
      }
      return $block;
  }
}

/**
 * Implementation of hook_theme().
 */
function exhibit_theme() {
  return array(
    'exhibit_definition' => array(
      'arguments' => array('node' => NULL),
    ),
  );
}

//////////////////////////////////////////////////////////////////////////////
// Node API hooks

/**
 * Implementation of hook_node_info().
 */
function exhibit_node_info() {
  return array(
    'exhibit' => array(
      'name'        => t('Exhibit'),
      'module'      => 'exhibit', //_node',
      'description' => t('An <em>exhibit</em> displays structured data in the form of rich visualizations that can be searched, filtered and sorted using faceted browsing.'),
      'has_title'   => TRUE,
      'title_label' => t('Title'),
      'has_body'    => TRUE,
      'body_label'  => t('Description'),
    ),
  );
}

/**
 * Implementation of hook_access().
 */
function exhibit_access($op, $node) {
  switch ($op) {
    case 'view':
      return user_access('access exhibits');
    case 'create':
      return user_access('create exhibits');
    case 'update':
      global $user;
      return user_access('edit exhibits') || (user_access('edit own exhibits') && $user->uid == $node->uid);
    case 'delete':
      global $user;
      return user_access('delete exhibits') || (user_access('delete own exhibits') && $user->uid == $node->uid);
  }
}

/**
 * Implementation of hook_load().
 */
function exhibit_load($node) {
  $exhibit = db_fetch_array(db_query('SELECT * FROM {exhibit_nodes} WHERE vid = %d', $node->vid));
  $exhibit['feeds'] = explode(',', $exhibit['feeds']);
  return (object)array('exhibit' => $exhibit);
}

/**
 * Implementation of hook_validate().
 */
function exhibit_validate(&$node) {}

/**
 * Implementation of hook_insert().
 */
function exhibit_insert($node) {
  $node->exhibit['feeds'] = implode(',', array_filter(array_values($node->exhibit['feeds']), 'trim'));
  db_query("INSERT INTO {exhibit_nodes} (nid, vid, feeds, definition, facet_definition) VALUES (%d, %d, '%s', '%s', '%s')", $node->nid, $node->vid, $node->exhibit['feeds'], $node->exhibit['definition'], $node->exhibit['facet_definition']);
}

/**
 * Implementation of hook_update().
 */
function exhibit_update($node) {
  if ($node->revision) {
    return exhibit_insert($node);
  }
  $node->exhibit['feeds'] = implode(',', array_filter(array_values($node->exhibit['feeds']), 'trim'));
  db_query("UPDATE {exhibit_nodes} SET feeds = '%s', definition = '%s', facet_definition = '%s' WHERE vid = %d", $node->exhibit['feeds'], $node->exhibit['definition'], $node->exhibit['facet_definition'], $node->vid);
}

/**
 * Implementation of hook_delete().
 */
function exhibit_delete($node) {
  db_query('DELETE FROM {exhibit_nodes} WHERE nid = %d', $node->nid);
}

/**
 * Implementation of hook_nodeapi().
 */
function exhibit_nodeapi(&$node, $op, $teaser, $page) {
  switch ($op) {
    case 'delete revision':
      db_query('DELETE FROM {exhibit_nodes} WHERE vid = %d', $node->vid);
      break;
  }
}

/**
 * Implementation of hook_form().
 */
function exhibit_form(&$node, &$param) {
  drupal_add_js(drupal_get_path('module', 'exhibit') .'/exhibit.js');
  drupal_add_js(array('exhibit' => exhibit_get_feeds('url')), 'setting');

  $type = node_get_types('type', $node);

  if ($type->has_title) {
    $form['title'] = array('#type' => 'textfield', '#title' => check_plain($type->title_label), '#required' => TRUE, '#default_value' => $node->title, '#weight' => -5);
  }

  if ($type->has_body) {
    // FIXME: this works around a bug in node_submit(), lines 782-793, which
    // causes the body field to be emptied when not using node_body_field()
    // to generate the body and format fieldset. Need to submit a core patch.
    $form['teaser_include'] = array('#type' => 'hidden', '#value' => '1');

    $form['body_filter'] = array('#type' => 'fieldset', '#title' => check_plain($type->body_label), '#collapsible' => TRUE, '#collapsed' => TRUE);
    $form['body_filter']['body'] = array('#type' => 'textarea', '#title' => t('Description'), '#default_value' => $node->body, '#required' => ($type->min_word_count > 0), '#rows' => 2);
    $form['body_filter']['format'] = filter_form($node->format);
  }

  $form['exhibit'] = array('#type' => 'fieldset', '#title' => t('Exhibit'), '#collapsible' => TRUE, '#collapsed' => FALSE, '#tree' => TRUE);
  $form['exhibit']['feeds'] = array('#type' => 'checkboxes', '#title' => t('Data feeds'), '#default_value' => !empty($node->exhibit['feeds']) ? $node->exhibit['feeds'] : array(), '#options' => exhibit_get_feeds('title'), '#attributes' => array('class' => 'exhibit-feed-checkbox'), '#prefix' => '<div id="feed-field-selection">', '#suffix' => '</div>');
  $form['exhibit']['definition'] = array('#type' => 'textarea', '#title' => t('Definition'), '#default_value' => !empty($node->exhibit['definition']) ? $node->exhibit['definition'] : theme('exhibit_definition'), '#rows' => 10);
  $form['exhibit']['facet_definition'] = array('#type' => 'textarea', '#title' => t('Facet definition'), '#default_value' => @$node->exhibit['facet_definition'], '#rows' => 5);
  $form['exhibit']['facet-generator-form-wrapper'] = array('#type' => 'fieldset', '#title' => t('Facet Generator'), '#collapsible' => TRUE, '#collapsed' => TRUE, '#tree' => TRUE, '#attributes' => array('id' => 'exhibit-facet-builder', 'style' => 'display:none;'), '#value' => '<div id="facet-generator-form"></div>');

  return $form;
}

/**
 * Implementation of hook_view().
 */
function exhibit_view($node, $teaser = FALSE, $page = FALSE) {
  // Load the SIMILE Exhibit API and any enabled extensions
  drupal_set_html_head('<script type="text/javascript" src="'. EXHIBIT_JS_URL .'"></script>'."\n");

  // Load any enabled Exhibit extensions
  foreach (exhibit_exhibit_views() as $id => $view) {
    if (variable_get('exhibit_extensions_'. $id, FALSE)) {
      drupal_set_html_head('<script type="text/javascript" src="'. $view['href'] .'"></script>'."\n");
    }
  }

  // Insert <LINK> references to all enabled data feeds
  foreach ($node->exhibit['feeds'] as $fid) {
    if ($feed = exhibit_feed_load($fid)) {
      exhibit_add_feed(exhibit_get_feed_url($feed), check_plain($feed['type']));
    }
  }

  $node = node_prepare($node, $teaser);
  $node->content['exhibit'] = array('#value' => $node->exhibit['definition'], '#weight' => 1);
  return $node;
}

//////////////////////////////////////////////////////////////////////////////
// Views API hooks

/**
 * Implementation of hook_views_api().
 */
function exhibit_views_api() {
  return array(
    'api'  => 2,
    'path' => drupal_get_path('module', 'exhibit'),
  );
}

//////////////////////////////////////////////////////////////////////////////
// Exhibit API hooks

/**
 * Implementation of hook_exhibit_views().
 */
function exhibit_exhibit_views() {
  return array(
    'tile'      => array(
      'title'   => t('Tile (default)'),
      'class'   => '',
    ),
    'thumbnail' => array(
      'title'   => t('Thumbnail'),
      'class'   => 'Thumbnail',
    ),
    'map'       => array(
      'title'   => t('Map'),
      'class'   => 'Map',
      'href'    => variable_get('exhibit_extensions_map_api', EXHIBIT_MAP_JS_URL) . '?gmapkey=' . (module_exists('gmap') ?  gmap_get_key() : variable_get('exhibit_gmap_key', '')),
    ),
    'barchart'  => array(
      'title'   => t('Barchart'),
      'class'   => 'Barchart',
      'href'    => variable_get('exhibit_extensions_barchart_api', EXHIBIT_BARCHART_JS_URL),
    ),
    'scatterplot' => array(
      'title'   => t('Scatterplot'),
      'class'   => 'Scatterplot',
      'href'    => variable_get('exhibit_extensions_scatterplot_api', EXHIBIT_SCATTERPLOT_JS_URL),
    ),
    'timeline'  => array(
      'title'   => t('Timeline'),
      'class'   => 'Timeline',
      'href'    => variable_get('exhibit_extensions_timeline_api', EXHIBIT_TIMELINE_JS_URL),
    ),
    'calendar'  => array(
      'title'   => t('Calendar'),
      'class'   => 'Calendar',
      'href'    => variable_get('exhibit_extensions_calendar_api', EXHIBIT_CALENDAR_JS_URL),
    ),
    'tabular'   => array(
      'title'   => t('Tabular'),
      'class'   => 'Tabular',
    ),
  );
}

//////////////////////////////////////////////////////////////////////////////
// Exhibit API functions

function exhibit_add_link($url) {
  drupal_add_link(array('rel' => 'meta', 'type' => 'application/json', 'title' => 'Exhibit JSON', 'href' => exhibit_get_url($url)));
}

function exhibit_get_url($url) {
  if (exhibit_is_link_internal($url)) {
    $url_parts = parse_url($url);
    // Handle views args
    if (isset($_GET['args'])) {
      $url_parts['path'] = preg_replace('/\%/', $_GET['args'], $url_parts['path']);
    }
    if (empty($url_parts['query'])) {
      return url($url_parts['path']);
    }
    else {
      return url($url_parts['path'], array('query' => $url_parts['query']));
    }
  }
  else {
    return url($url, array('external' => TRUE));
  }
}

function exhibit_is_link_internal($url) {
  return (bool)!preg_match('!^[\w\d\+\-]+://!', $url);
}

function exhibit_add_feed($url, $type = 'application/json') {
  switch ($type) {
    case 'application/vnd.google-spreadsheet': // special case
      drupal_add_link(array('rel' => 'exhibit/data', 'href' => $url, 'type' => 'application/jsonp', 'ex:converter' => 'googleSpreadsheets'));
      break;
    default:
      drupal_add_link(array('rel' => 'exhibit/data', 'href' => $url, 'type' => $type));
      break;
  }
}

function exhibit_feed_load($fid) {
  if (is_numeric($fid)) {
    return db_fetch_array(db_query('SELECT f.* FROM {exhibit_feeds} f WHERE f.fid = %d', $fid));
  }
  else {
    if (module_exists('views')) {
      $views = views_get_all_views();
      foreach ($views as $view) {
        // Skip disabled views or broken views
        if (!empty($view->disabled) || empty($view->display)) {
          continue;
        }

        // Check each display, add those using the Exhibit JSON style plugin
        foreach (array_keys($view->display) as $id) {
          $plugin = views_fetch_plugin_data('display', $view->display[$id]->display_plugin);
          $display_options = $view->display[$id]->display_options;
          if ($plugin['handler'] == 'views_plugin_display_feed' && $display_options['style_plugin'] == 'exhibit_json') {
            $view_feed_id = $view->vid . '_' . $id;
            if ($view_feed_id == $fid) {
              return array('fid' => $view_feed_id,
                            'module' => 'views',
                            'title' => $view->name . ': ' . $view->display[$id]->display_title,
                            'enabled' => TRUE,
                            'cache' => FALSE,
                            'type' => 'application/json',
                            'url' => $display_options['path']);
            }
          }
        }
      }
    }
  }
}

function exhibit_get_feeds($key = NULL) {
  $feeds = array();
  $result = db_query('SELECT f.* FROM {exhibit_feeds} f ORDER BY f.title ASC');
  while ($feed = db_fetch_object($result)) {
    $feeds[$feed->fid] = $key ? $feed->$key : $feed;
  }

  // Check for Exhibit JSON feeds in views and add automaticall add them to the list
  if (module_exists('views')) {
    $views = views_get_all_views();
    foreach ($views as $view) {
      // Skip disabled views or broken views
      if (!empty($view->disabled) || empty($view->display)) {
        continue;
      }

      // Check each display, add those using the Exhibit JSON style plugin
      foreach (array_keys($view->display) as $id) {
        $plugin = views_fetch_plugin_data('display', $view->display[$id]->display_plugin);
        $display_options = $view->display[$id]->display_options;
        if ($plugin['handler'] == 'views_plugin_display_feed' && $display_options['style_plugin'] == 'exhibit_json') {
          $view_feed_id = $view->vid . '_' . $id;
          if ($key) {
            switch ($key) {
              case 'fid':
                $feeds[$view_feed_id] = $view_feed_id;
                break;
              case 'module':
                $feeds[$view_feed_id] = 'views';
                break;
              case 'title':
                $feeds[$view_feed_id] = l($view->name . ': ' . $view->display[$id]->display_title, 'admin/build/views/edit/' . $view->name);
                break;
              case 'enabled':
                $feeds[$view_feed_id] = TRUE;
                break;
              case 'cache':
                $feeds[$view_feed_id] = FALSE;
                break;
              case 'type':
                $feeds[$view_feed_id] = 'application/json';
                break;
              case 'url':
                $feeds[$view_feed_id] = $display_options['path'];
                break;
            }
          }
          else {
            $feeds[$view_feed_id] = (object)array('fid' => $view_feed_id,
                                                  'module' => 'views',
                                                  'title' => l($view->name . ': ' . $view->display[$id]->display_title, 'admin/build/views/edit/' . $view->name),
                                                  'enabled' => TRUE,
                                                  'cache' => FALSE,
                                                  'type' => 'application/json',
                                                  'url' => $display_options['path']);
          }
        }
      }
    }
  }

  return $feeds;
}

function exhibit_get_feed_url($feed) {
  $feed = (object)$feed;
  return exhibit_get_url(!empty($feed->cache) ? 'exhibit/feeds/' . $feed->fid : $feed->url);
}

function exhibit_get_feed_contents($url) {
  if (exhibit_is_link_internal($url)) {
    // Internal Drupal path
    ob_start();
    $result = $url ? menu_execute_active_handler($url) : MENU_NOT_FOUND;
    $output = ob_get_clean();
    if (is_int($result)) {
      switch ($result) {
        case MENU_NOT_FOUND:
          return die(drupal_not_found());
        case MENU_ACCESS_DENIED:
          return die(drupal_access_denied());
      }
    }
  }
  else {
    // External URL
    $output = file_get_contents($url);
  }
  return $output;
}

function exhibit_json($items, $types = NULL, $properties = NULL) {
  return exhibit_compact_item(array(
    'types'      => $types,
    'properties' => $properties,
    'items'      => $items,
  ));
}

function exhibit_compact_item($item) {
  foreach ($item as $k => $v) {
    if (is_null($v)) {
      unset($item[$k]);
    }
  }
  return $item;
}

//////////////////////////////////////////////////////////////////////////////
// Theme callbacks

function theme_exhibit_definition() { // TODO
  return '<div ex:role="viewPanel"><div ex:role="view"></div></div>';
}

function theme_exhibit_lens() { // TODO
  return '<div ex:content=".label" class="label"></div>';
}