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headerimage.module in Header image 6

Same filename and directory in other branches
  1. 5 headerimage.module
  2. 7 headerimage.module

headerimage.module Conditionally display an node in a block.

WHISH LIST: create CCK node type at install (see: http://drupal.org/node/82908) (maybe: http://drupal.org/node/101742)

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headerimage.module
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<?php

/**
 * @file headerimage.module
 * Conditionally display an node in a block.
 *
 * WHISH LIST:
 *   create CCK node type at install (see: http://drupal.org/node/82908) (maybe: http://drupal.org/node/101742)
 */

/**
 * Implementation of hook_menu()
 */
function headerimage_menu() {
  $items['admin/settings/headerimage'] = array(
    'title' => t('Header Image'),
    'description' => t('Control the Header Image.'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'headerimage_settings_block_add',
    ),
    'access arguments' => array(
      'administer header image',
    ),
    'type' => MENU_NORMAL_ITEM,
    'file' => 'headerimage.admin.inc',
  );
  $items['admin/settings/headerimage/list'] = array(
    'title' => t('List'),
    'page arguments' => array(
      'headerimage_settings_block_add',
    ),
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['admin/settings/headerimage/settings'] = array(
    'title' => t('Settings'),
    'page arguments' => array(
      'headerimage_settings_form',
    ),
    'access arguments' => array(
      'administer header image',
    ),
    'type' => MENU_LOCAL_TASK,
    'weight' => 10,
  );
  $items['admin/settings/headerimage/edit/%'] = array(
    'title' => t('Edit Header Image block'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'headerimage_settings_block_edit',
      4,
    ),
    'access arguments' => array(
      'administer header image',
    ),
    'type' => MENU_CALLBACK,
  );
  $items['admin/settings/headerimage/delete/%'] = array(
    'title' => t('Delete Header Image block'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'headerimage_block_confirm_delete',
      4,
    ),
    'access arguments' => array(
      'administer header image',
    ),
    'type' => MENU_CALLBACK,
    'file' => 'headerimage.admin.inc',
  );
  return $items;
}

/**
 * Edit block data form
 */
function headerimage_settings_block_edit(&$form_state, $delta) {
  $blocks = headerimage_get_blocks();
  $form = array();
  $form['delta'] = array(
    '#type' => 'hidden',
    '#value' => $delta,
  );
  $form['title'] = array(
    '#type' => 'textfield',
    '#title' => t('Block title'),
    '#description' => t('The block name must be unique.'),
    '#default_value' => $blocks[$delta],
    '#required' => true,
  );
  $form['op'] = array(
    '#type' => 'submit',
    '#value' => t('Save'),
  );
  $form['#redirect'] = 'admin/settings/headerimage';
  return $form;
}
function headerimage_settings_block_edit_validate($form, &$form_state) {
  $blocks = headerimage_get_blocks();

  // Remove current blockname to prevent false error
  unset($blocks[$form_state['values']['delta']]);
  if (!empty($blocks)) {

    // Check if name is unique
    if (in_array($form_state['values']['title'], $blocks)) {
      form_set_error('', t('Header Image block %s already exists. Please use a different name.', array(
        '%s' => $form_state['values']['title'],
      )));
    }
  }
}
function headerimage_settings_block_edit_submit($form, &$form_state) {
  db_query("UPDATE {headerimage_block} SET title = '%s' WHERE delta = %d", $form_state['values']['title'], $form_state['values']['delta']);
  drupal_set_message(t('Header Image block updated.'));
  return 'admin/settings/headerimage';
}

/**
 * Implementation of hook_perm().
 */
function headerimage_perm() {
  return array(
    'administer header image',
    'maintain display conditions',
    'view header image',
  );
}

/**
 * Implementation of hook_block().
 */
function headerimage_block($op = 'list', $delta = 0, $edit = array()) {
  switch ($op) {
    case 'list':
      $headerimage_blocks = headerimage_get_blocks();
      foreach ($headerimage_blocks as $key => $name) {
        $blocks[$key]['info'] = check_plain($name);
      }
      return $blocks;
      break;
    case 'configure':
      return headerimage_block_configure($delta);
    case 'save':
      variable_set('headerimage_block_' . $delta . '_random_fallback', $edit['random_fallback']);
      break;
    case 'view':
      if (user_access('view header image')) {

        // select node from nodes assigned to this block
        $nid = headerimage_select_node($delta);
        $teaser = variable_get('headerimage_teaser', true);

        // prepare block output
        if (!empty($nid)) {
          $node = node_load($nid);
          $node = node_prepare($node, $teaser);

          //use node teaser view

          // mimic node_view
          $node = node_build_content($node, $teaser, false);
          $content = drupal_render($node->content);
          if ($teaser) {
            $node->teaser = $content;
            unset($node->body);
          }
          else {
            $node->body = $content;
            unset($node->teaser);
          }
          node_invoke_nodeapi($node, 'alter', $teaser);
          $block['content'] = theme('headerimage_block', $node, $teaser);
          return $block;
        }
      }
      break;
  }
}

/**
 * Select a node to be displayed in the block
 *
 * Node selection by (1)weight and (2)condition.
 * If multiple conditions are present, any true condition will select the node.
 * If no node is selected by the conditions and random fallback selection is
 * enabled for the block, one of the available nodes will be selected at random.
 *
 * @param $block
 *   The headerimage block number ($delta)
 *
 * @return
 *   nid of the selected node
 *   null: no node selected
 */
function headerimage_select_node($block) {
  $result = db_query("SELECT nid, conditions FROM {headerimage} WHERE block = %d ORDER BY weight, nid ASC", $block);
  while ($header_image = db_fetch_object($result)) {
    $conditions = unserialize($header_image->conditions);
    $match = false;

    // Store the nid in an array for the random selection fallback option.
    $block_nids[] = $header_image->nid;
    $selected_types = variable_get('headerimage_condition_types', array(
      'nid' => 'nid',
    ));
    foreach ($conditions as $type => $condition) {
      if (!empty($condition) && !empty($selected_types[$type])) {
        switch ($type) {
          case 'nid':
            $match = headerimage_eval_nid($condition);
            break;
          case 'url':
            $match = headerimage_eval_url($condition);
            break;
          case 'taxonomy':
            $match = headerimage_eval_taxonomy($condition);
            break;
          case 'book':
            $match = headerimage_eval_book($condition);
            break;
          case 'nodetype':
            $match = headerimage_eval_nodetype($condition);
            break;
          case 'php':
            $match = drupal_eval($condition);
            break;
        }
      }
      if ($match) {
        break;
      }
    }
    if ($match) {
      break;
    }
  }
  if ($match) {
    return $header_image->nid;
  }
  elseif (variable_get('headerimage_block_' . $block . '_random_fallback', 0) && count($block_nids)) {
    return $block_nids[array_rand($block_nids)];
  }
}

/**
 * Evaluate nid condition
 *
 * Checks if current page is in list of nids
 *
 * @param $condition
 *   comma separated list of nids
 *
 * @return
 *   true: current page is in $condition
 *   false: if not
 *   null: current page is not a node
 */
function headerimage_eval_nid($condition) {
  if (arg(0) == 'node' && is_numeric(arg(1))) {
    $nids = explode(',', $condition);
    $match = in_array(arg(1), $nids);
  }
  return $match;
}

/**
 * Evaluate url condition
 *
 * Check if current page is in selected paths
 *
 * @param $condition
 *   text with paths or '<frontpage>'. May contain wild cards.
 *
 * @return
 *   true: current page matches one of the $condition paths;
 *   false: if not
 */
function headerimage_eval_url($condition) {
  $path = drupal_get_path_alias($_GET['q']);
  $regexp = '/^(' . preg_replace(array(
    '/(\\r\\n?|\\n)/',
    '/\\\\\\*/',
    '/(^|\\|)\\\\<front\\\\>($|\\|)/',
  ), array(
    '|',
    '.*',
    '\\1' . preg_quote(variable_get('site_frontpage', 'node'), '/') . '\\2',
  ), preg_quote($condition, '/')) . ')$/';

  // Compare with the internal and path alias (if any).
  $match = preg_match($regexp, $path);
  if ($match) {
    return true;
  }
  if ($path != $_GET['q']) {
    $match = preg_match($regexp, $_GET['q']);
  }
  return $match;
}

/**
 * Evaluate taxonomy condition
 *
 * Check if current page has selected taxonomy terms
 *
 * @param $condition
 *   array of taxonomy term tid's
 *
 * @return
 *   true: current page contains one of $condition's tags
 *   false: if not
 *   null: current page is not a node
 */
function headerimage_eval_taxonomy($condition) {
  if (arg(0) == 'node' && is_numeric(arg(1))) {
    if ($node = menu_get_object()) {
      foreach (array_keys($node->taxonomy) as $key) {
        if (isset($condition[$key])) {
          return true;
        }
      }
      return false;
    }
  }
  return null;
}

/**
 * Evaluate book condition
 *
 * Return true if current node is a page of the book(s) selected in the condition
 *
 * @param $condition
 *   array of book root nid's
 *
 * @return
 *   true: current node is a page in $condition's books
 *   false: if not
 *   null: current page is not a node
 */
function headerimage_eval_book($condition) {
  if (arg(0) == 'node' && is_numeric(arg(1))) {

    // check if current node is one of the condition pages (books)
    $match = in_array(arg(1), $condition);
    if ($match) {
      return true;
    }

    // check if current page is part of book in the condition pages
    $bid = db_result(db_query("SELECT bid FROM {book} WHERE nid = %d", arg(1)));
    $match = in_array($bid, $condition);
  }
  return $match;
}

/**
 * Evaluate node type condition
 *
 * Return true if type of current node is selected
 *
 * @param $condition
 *   array of selected node types
 *
 * @return
 *   true: current node type is selected
 *   false: if not
 *   null: current page is not a node
 */
function headerimage_eval_nodetype($condition) {
  $match = FALSE;
  if (arg(0) == 'node' && is_numeric(arg(1))) {
    $node = menu_get_object();
    $match = in_array($node->type, $condition);
  }
  return $match;
}

/**
 * Implementation of hook_form_alter
 *
 * Add display conditions to header image node forms
 */
function headerimage_form_alter(&$form, &$form_state, $form_id) {
  if (strpos($form_id, '_node_form') && isset($form['type']['#value']) && in_array($form['type']['#value'], variable_get('headerimage_node_type', array()), true) && user_access('maintain display conditions')) {
    $form['headerimage'] = array(
      '#type' => 'fieldset',
      '#title' => t('Display conditions'),
      '#description' => t('This node is displayed in a Header Image block when one of the conditions below are evaluated true.'),
      '#collapsible' => true,
      '#collapsed' => false,
      '#weight' => -2,
    );
    $form['headerimage']['headerimage_block'] = array(
      '#type' => 'select',
      '#title' => t('Block name'),
      '#description' => t('The block in which this node is displayed.'),
      '#options' => headerimage_get_blocks(),
      '#default_value' => $form['#node']->headerimage_block,
      '#required' => true,
      '#multiple' => false,
    );
    $form['headerimage']['headerimage_weight'] = array(
      '#type' => 'weight',
      '#title' => t('Condition weight'),
      '#description' => t('Determines the order of in which the nodes are evaluated. The conditions of a node with a smaller weight will be evaluated first, those with a larger weight are evaluated later. A default image (the one displayed if the conditions of all other images fail) should have the largest weight: 10.'),
      '#default_value' => $form['#node']->headerimage_weight,
      '#delta' => 10,
    );
    $condition_types = variable_get(headerimage_condition_types, array(
      'nid' => 'nid',
    ));
    if (!empty($condition_types)) {
      foreach ($condition_types as $type) {
        if ($type != '0') {
          $all_types = headerimage_get_condition_types();
          $title = t("@name condition", array(
            '@name' => $all_types[$type],
          ));
          $name = 'headerimage_condition_' . $type;
          switch ($type) {
            case 'nid':
              $form['headerimage'][$name] = array(
                '#type' => 'textarea',
                '#title' => $title,
                '#description' => t("Enter node id's separated by comma's."),
                '#default_value' => $form['#node']->{$name},
                '#rows' => 4,
              );
              break;
            case 'url':
              $form['headerimage'][$name] = array(
                '#type' => 'textarea',
                '#title' => $title,
                '#description' => t("Enter one page per line as Drupal paths. The '*' character is a wildcard. Example paths are blog for the blog page and blog/* for every personal blog. %front is the front page.", array(
                  '%front' => '<front>',
                )),
                '#default_value' => $form['#node']->{$name},
                '#rows' => 4,
              );
              break;
            case 'taxonomy':
              $options = array();
              if (module_exists('taxonomy')) {
                $vocab = taxonomy_get_vocabularies();
                if (!empty($vocab)) {
                  foreach ($vocab as $v) {
                    $taxonomy = taxonomy_get_tree($v->vid);
                    if (!empty($taxonomy)) {
                      foreach ($taxonomy as $tag) {
                        $options[$tag->tid] = check_plain($tag->name);
                      }
                    }
                  }
                }
                if (!empty($options)) {
                  $description = t("One tag or multiple tags can be selected.");
                }
                else {
                  drupal_set_message(t("No vocabulary or tags defined. Please create vocabulary and tags or remove taxonomy from the !settings.", array(
                    '!settings' => l(t('Header Image settings'), 'admin/settings/headerimage/settings'),
                  )));
                  break;
                }
                $form['headerimage'][$name] = array(
                  '#type' => 'select',
                  '#title' => $title,
                  '#description' => $description,
                  '#default_value' => $form['#node']->{$name},
                  '#options' => $options,
                  '#multiple' => true,
                );
              }
              else {
                drupal_set_message(t("The taxonomy module is not enabled. Please enable the module or remove it from the !settings.", array(
                  '!settings' => l(t('Header Image settings'), 'admin/settings/headerimage/settings'),
                )));
              }
              break;
            case 'book':
              if (module_exists('book')) {
                $options = array();
                $books = book_get_books();
                if (count($books)) {
                  $description = t("One book or multiple books can be selected.");
                  foreach ($books as $key => $book) {
                    $options[$key] = $book['title'];
                  }
                }
                else {
                  $description = t("No books defined. Please create a book before using it as a condition.");
                }
                $form['headerimage'][$name] = array(
                  '#type' => 'select',
                  '#title' => $title,
                  '#description' => $description,
                  '#default_value' => $form['#node']->{$name},
                  '#options' => $options,
                  '#multiple' => true,
                );
              }
              else {
                drupal_set_message(t("The book module is not enabled. Please enable the module or remove it from the !settings.", array(
                  '!settings' => l(t('Header Image settings'), 'admin/settings/headerimage/settings'),
                )));
              }
              break;
            case 'nodetype':
              $nodes = node_get_types();
              foreach ($nodes as $node) {
                $nodetype[$node->type] = check_plain($node->name);
              }
              $form['headerimage'][$name] = array(
                '#type' => 'select',
                '#title' => $title,
                '#description' => t('Select one or multiple node types'),
                '#default_value' => $form['#node']->{$name},
                '#options' => $nodetype,
                '#multiple' => true,
              );
              break;
            case 'php':
              $form['headerimage'][$name] = array(
                '#type' => 'textarea',
                '#title' => $title,
                '#description' => t("Enter PHP code between &lt;?php ?&gt; tags. Note that executing incorrect PHP-code can break your Drupal site."),
                '#default_value' => $form['#node']->{$name},
                '#rows' => 4,
              );
              break;
          }
        }
      }
    }
  }
}

/**
 * Return a form with a list of Header Image nodes
 *
 * Nodes assigned to Header Image block $delta are listed with weight and
 * edit link
 *
 * @param $delta
 *   Header Image block delta
 *
 * @return
 *   form array
 */
function headerimage_block_configure($delta) {
  $result = db_query("SELECT title, weight, n.nid FROM {headerimage} hi JOIN {node} n ON n.nid = hi.nid AND hi.block = %d ORDER BY weight, nid ASC", $delta);

  // Table with image set details
  $rows = array();
  while ($data = db_fetch_object($result)) {
    $rows[] = array(
      'node' => check_plain($data->title),
      'weight' => $data->weight,
      'edit' => l(t('Edit'), "node/{$data->nid}/edit"),
    );
  }
  if (empty($rows)) {
    $rows[] = array(
      array(
        'data' => t('No Header Image nodes assigned to this block.'),
        'colspan' => '3',
      ),
    );
  }
  $header = array(
    t('Node'),
    t('Weight'),
    array(
      'data' => t('Operation'),
      'colspan' => '1',
    ),
  );
  $output = theme('table', $header, $rows, array(
    'id' => 'imageblock',
  ));

  // Pack the tabel in form as markup text.
  $form['headerimage']['description'] = array(
    '#prefix' => '<p>',
    '#value' => t('The table below contains the nodes which will be displayed in this block when there condition evaluates to true.'),
    '#suffix' => '</p>',
  );
  $form['headerimage']['table'] = array(
    '#prefix' => '<div>',
    '#value' => $output,
    '#suffix' => '</div>',
  );
  $form['headerimage']['random_fallback'] = array(
    '#type' => 'checkbox',
    '#title' => t('Enable a random fallback selection'),
    '#default_value' => variable_get('headerimage_block_' . $delta . '_random_fallback', 0),
    '#description' => t('If no node is selected by the conditions, select a random node from those assigned to this block.'),
  );
  return $form;
}

/**
 * Implementation of hook_nodeapi
 */
function headerimage_nodeapi(&$node, $op) {
  if (!empty($node->type) && in_array($node->type, variable_get('headerimage_node_type', array()), true)) {
    switch ($op) {
      case 'update':
        db_query("DELETE from {headerimage} WHERE nid = %d", $node->nid);
      case 'insert':

        // Pack all conditions into one array
        $conditions = variable_get(headerimage_condition_types, array(
          'nid' => 'nid',
        ));
        if (!empty($conditions)) {
          foreach ($conditions as $condition) {
            if ($condition != '0') {
              $name = 'headerimage_condition_' . $condition;
              $conditions[$condition] = $node->{$name};
            }
          }
        }
        db_query("INSERT INTO {headerimage} (nid, block, weight, conditions)\n                 VALUES (%d, %d, %d, '%s')", $node->nid, $node->headerimage_block, $node->headerimage_weight, serialize($conditions));
        break;
      case 'prepare':

        // Load data from database if node is edited
        $result = db_fetch_object(db_query("SELECT * from {headerimage} where nid = %d", $node->nid));
        $node->headerimage_block = $result->block;
        $node->headerimage_weight = $result->weight;
        $conditions = unserialize($result->conditions);
        if (!empty($conditions)) {
          foreach ($conditions as $condition => $value) {
            $name = 'headerimage_condition_' . $condition;
            $node->{$name} = $value;
          }
        }
        break;
      case 'delete':
        db_query("DELETE from {headerimage} WHERE nid = %d", $node->nid);
        break;
    }
  }
}

/**
 * Implementation of hook_help
 */
function headerimage_help($path, $arg) {
  switch ($path) {
    case 'admin/help#headerimage':

      // Determine the status of the installation
      $type_is_set = count(variable_get('headerimage_node_type', array())) ? t('(DONE)') : t('(TO DO)');
      $block_is_created = count(headerimage_get_blocks()) ? t('(DONE)') : t('(TO DO)');
      foreach (headerimage_get_blocks() as $delta => $name) {
        $block_has_nodes = db_result(db_query("SELECT nid FROM {headerimage} WHERE block = %d", $delta));
        if ($block_has_nodes) {
          break;
        }
      }
      $block_has_nodes = $block_has_nodes ? t('(DONE)') : t('(TO DO)');
      foreach (headerimage_get_blocks() as $delta => $name) {
        $block_in_region = db_result(db_query("SELECT region FROM {blocks} WHERE module = '%s' AND theme = '%s' AND delta = %d", 'headerimage', variable_get('theme_default', 'garland'), $delta));
        if ($block_in_region) {
          break;
        }
      }
      $block_in_region = $block_in_region ? t('(DONE)') : t('(TO DO)');
      $output = "<p>" . t('Header Image allows you to to display an image on selected pages. It can display one image at the front page, a different one at FAQ pages and yet another at all other pages.') . "</p>\n";
      $output .= "<p>" . t('Visibility of each image, included in a node, can be determined by node ID, path, taxonomy, book, node type or custom PHP code. Header Image uses an arbitrary node type.') . "</p>\n";
      $output .= "<p>" . t('Multiple images (nodes) can be displayed in one block, with each image having its own conditions. Using a weight per node the order of selection can be controlled.') . "</p>\n";
      $output .= "<h2>" . t('Installation') . "</h2>\n";
      $output .= "<p>" . t('<ol>
<li>Set up <a href="!permissions">permissions</a>.</li>
<li>Optionally <a href="!create_node_type">create a node type</a> which will contain the header image.</li>
<li><a href="!set_node_type">Select a node type</a> to be used as Header Image. %status_type</li>
<li><a href="!create_header_image_block">Create a Header Image block</a>. %status_create</li>
<li>Create Header Image nodes. Select a Header Image block and set display conditions for each node. %status_assign</li>
<li><a href="!assign_header_image_block">Assign the Header Image block</a> to a region. %status_region</li>
</ol>', array(
        '!permissions' => url('admin/user/permissions'),
        '!create_node_type' => url('admin/content/types/add'),
        '!set_node_type' => url('admin/settings/headerimage/settings'),
        '%status_type' => $type_is_set,
        '!create_header_image_block' => url('admin/settings/headerimage'),
        '%status_create' => $block_is_created,
        '!assign_header_image_block' => url('admin/build/block'),
        '%status_assign' => $block_has_nodes,
        '%status_region' => $block_in_region,
      )) . "</p>\n";
      $output .= "<p>" . t('For more information please read the <a href="@handbook">configuration and customization handbook</a> on Header Image.', array(
        '@handbook' => 'http://drupal.org/node/201426/',
      )) . "</p>\n";
      return $output;
  }
}

/**
 * Return all condition types available
 *
 * @return
 *   array of condition types
 */
function headerimage_get_condition_types() {
  return array(
    'nid' => t('Node ID'),
    'url' => t('URL'),
    'taxonomy' => t('Taxonomy'),
    'book' => t('Book'),
    'nodetype' => t('Node type'),
    'php' => t('PHP'),
  );
}

/**
 * Return all Header Image blocks
 *
 * @return
 *   array of Header Image blocks
 */
function headerimage_get_blocks() {
  static $blocks;
  if (!isset($blocks)) {
    $blocks = array();
    $result = db_query("SELECT * FROM {headerimage_block}");
    while ($block = db_fetch_object($result)) {
      if (!empty($block)) {
        $blocks[$block->delta] = $block->title;
      }
    }
  }
  return $blocks;
}

/**
 * Implementation of hook_theme()
 */
function headerimage_theme() {
  return array(
    'headerimage_block' => array(
      'template' => 'headerimage-block',
      'arguments' => array(
        'node' => NULL,
        'teaser' => NULL,
      ),
    ),
  );
}

/**
 * Process variables to format the headerimage block.
 *
 * $variables contains:
 * - $node
 * - $teaser: TRUE = display node as teaser; FALSE = display full node
 *
 * @see headerimage-block.tpl.php
 */
function template_preprocess_headerimage_block(&$variables) {
  $node = $variables['node'];
  $teaser = $variables['teaser'];
  $variables['unpublished'] = !$node->status;
  if ($teaser && isset($node->teaser)) {
    $variables['content'] = $node->teaser;
  }
  else {
    $variables['content'] = $node->body;
  }
}

Functions

Namesort descending Description
headerimage_block Implementation of hook_block().
headerimage_block_configure Return a form with a list of Header Image nodes
headerimage_eval_book Evaluate book condition
headerimage_eval_nid Evaluate nid condition
headerimage_eval_nodetype Evaluate node type condition
headerimage_eval_taxonomy Evaluate taxonomy condition
headerimage_eval_url Evaluate url condition
headerimage_form_alter Implementation of hook_form_alter
headerimage_get_blocks Return all Header Image blocks
headerimage_get_condition_types Return all condition types available
headerimage_help Implementation of hook_help
headerimage_menu Implementation of hook_menu()
headerimage_nodeapi Implementation of hook_nodeapi
headerimage_perm Implementation of hook_perm().
headerimage_select_node Select a node to be displayed in the block
headerimage_settings_block_edit Edit block data form
headerimage_settings_block_edit_submit
headerimage_settings_block_edit_validate
headerimage_theme Implementation of hook_theme()
template_preprocess_headerimage_block Process variables to format the headerimage block.