<?php
// $Id$


// Module metainfo
/**
* Implements hook_node_info()
*/
function mkdru_node_info() {
  return array(
    'mkdru' => array(
      'name'        => t("Pazpar2 metasearch interface"),
      'base'        => 'mkdru',
      'description' => t("Metasearch interface for Z39.50/SRU and other targets via a Pazpar2/Service Proxy backend"),
    )
  );
}

/**
 * Implements hook_search_info()
 */
function mkdru_search_info() {
  return array(
    'title'               => 'Meta search',
    'path'                => 'meta',
    'conditions_callback' => 'mkdru_search_conditions_callback',
  );
}

/**
 * Implements hook_search_page()
 */
function mkdru_search_page($results) {
  $output['prefix']['#markup'] = theme('mkdru_results');
  $output['suffix']['#markup'] = '';
  return $output;
}

/**
 * Implements hook_ding_facetbrowser()
 */
function mkdru_ding_facetbrowser() {
	$results             = new stdClass();
  $results->facets     = array();
  $results->show_empty = TRUE; # Show an empty facetbrowser block, even if search didn't return any results
  return $results;
}

/**
 * Search callback function that is invoked by search_view()
 */
function mkdru_search_conditions_callback($keys) {}

/**
 * Implement hook_search_execute()
 */
function mkdru_search_execute($keys = NULL, $conditions = NULL) {
  $path = drupal_get_path('module', 'mkdru');
  // Include client library.
  drupal_add_js(variable_get('pz2_js_path', 'pazpar2/js') . '/pz2.js',
    array('type' => 'file', 'scope' => 'footer'));
  drupal_add_library('overlay', 'jquery-bbq');
  drupal_add_js($path . '/mkdru.theme.js',
    array('type' => 'file', 'scope' => 'footer'));
  drupal_add_js($path . '/mkdru.client.js',
    array('type' => 'file', 'scope' => 'footer'));
  drupal_add_js(array('mkdru' =>
    array(
      'use_sessions' => variable_get('use_sessions', '1'),
      'pz2_path'     => variable_get('pz2_path', '/pazpar2/search.pz2'),
      'sp_user'      => variable_get('sp_user', ''),
      'sp_pass'      => variable_get('sp_pass', ''),
      'query'        => $keys,
    )
  ), 'setting');

  return array();
}

/**
* Implements hook_permission()
*/
function mkdru_permission() {
  return array(
    'administer metasearch interfaces' => array(
      'title' => t('Administer Pazpar2 metasearch integration'),
    ),
    'create metasearch interface' => array(
      'title' => t('Create metasearch interface'),
    ),
    'edit any metasearch interface' => array(
      'title' => t('Edit any metasearch interface'),
    ),
    'edit own metasearch interface' => array(
      'title' => t('Edit own metasearch interface'),
    ),
  );
}

/**
* Implements hook_node_access()
*/
function mkdru_node_access($node, $op, $account) {
  if ($op == 'create') {
    // Only users with permission to do so may create this node type.
    return user_access('create metasearch interface', $account);
  }

  // Users who create a node may edit or delete it later, assuming they have the
  // necessary permissions.
  if ($op == 'update' || $op == 'delete') {
    if (user_access('edit own metasearch interface', $account) && ($account->uid == $node->uid)) {
      return TRUE;
    }
    elseif (user_access('edit any metasearch interface', $account)) {
      return TRUE;
    }
  }
}

/**
* Implements hook_menu()
*/
function mkdru_menu() {
  $items['admin/settings/mkdru'] = array(
    'title' => 'mkdru Settings',
    'description' => 'Settings for mkdru.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('mkdru_admin_settings'),
    'access arguments' => array('administer site configuration'),
    'type' => MENU_NORMAL_ITEM,
    'file' => 'mkdru.admin.inc',
  );
  return $items;
}

/**
* Implementation of hook_init()
*/
function mkdru_init() {
  // Applies our module specific CSS to all pages. This works best because
  // all CSS is aggregated and cached so we reduce the number of HTTP 
  // requests and the size is negligible.
  drupal_add_css(drupal_get_path('module', 'mkdru') .'/mkdru.css');
}


// Node config
/**
* Implements hook_form()
*/
function mkdru_form(&$node, $form_state) {
  $type = node_type_get_type($node);

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

  $form['search_settings']  = array(
    '#type' => 'fieldset',
    '#title' => t('Pazpar2/Service Proxy search settings'),
    '#collapsible' => TRUE,
    '#collapsed' => FALSE
  );
  $form['search_settings']['pz2_path'] = array(
    '#type' => 'textfield',
    '#title' => t('Pazpar2/Service Proxy path'),
    '#description' => t('Path that takes Pazpar2 commands via HTTP'),
    '#required' => TRUE,
    '#default_value' => isset($node->mkdru->pz2_path) ? $node->mkdru->pz2_path : '/pazpar2/search.pz2',
  );
  $form['search_settings']['use_sessions'] = array(
    '#type' => 'checkbox',
    '#title' => t('Session handling'),
    '#description' => t('Disable for use with Service Proxy'),
    '#default_value' => isset($node->mkdru->use_sessions) ? $node->mkdru->use_sessions : 1,
  );

  $form['sp_settings']  = array(
    '#type' => 'fieldset',
    '#title' => t('Service Proxy specific settings'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE
  );
  $form['sp_settings']['sp_user'] = array(
    '#type' => 'textfield',
    '#title' => t('Service Proxy username'),
    '#description' => t('Service Proxy username'),
    '#required' => FALSE,
    '#default_value' => isset($node->mkdru->sp_user) ? 
      $node->mkdru->sp_user : '',
  );
  $form['sp_settings']['sp_pass'] = array(
    '#type' => 'textfield',
    '#title' => t('Service Proxy password'),
    '#description' => t('Service Proxy password'),
    '#required' => FALSE,
    '#default_value' => isset($node->mkdru->sp_pass) ? 
      $node->mkdru->sp_pass : '',
  );

  $form['display_settings']  = array(
    '#type' => 'fieldset',
    '#title' => t('Display settings'),
    '#collapsible' => TRUE,
    '#collapsed' => FALSE
  );
  $form['display_settings']['source_max'] = array(
    '#type' => 'textfield',
    '#title' => t('Number of sources to display'),
    '#required' => TRUE,
    '#default_value' => isset($node->mkdru->source_max) ? $node->mkdru->source_max : 10,
    '#size' => 3,
    '#maxlength' => 3,
  );
  $form['display_settings']['author_max'] = array(
    '#type' => 'textfield',
    '#title' => t('Number of authors to display'),
    '#required' => TRUE,
    '#default_value' => isset($node->mkdru->author_max) ? $node->mkdru->author_max : 10,
    '#size' => 3,
    '#maxlength' => 3,
  );
  $form['display_settings']['subject_max'] = array(
    '#type' => 'textfield',
    '#title' => t('Number of subjects to display'),
    '#required' => TRUE,
    '#default_value' => isset($node->mkdru->subject_max) ? $node->mkdru->subject_max : 10,
    '#size' => 3,
    '#maxlength' => 3,
  );
  return $form;
}


/**
* Implements hook_validate()
*/
function mkdru_validate($node) {
  if (!is_numeric($node->source_max)) {
    form_set_error('source_max', t('Please enter a number.'));
  }
  if (!is_numeric($node->author_max)) {
    form_set_error('author_max', t('Please enter a number.'));
  }
  if (!is_numeric($node->subject_max)) {
    form_set_error('subject_max', t('Please enter a number.'));
  }
}

/**
* Implements hook_insert().
*/
function mkdru_insert($node) {
  drupal_write_record('mkdru', $node);
}

/**
* Implements hook_update().
*/
function mkdru_update($node) {
  if ($node->revision) {
    // New revision; treat it as a new record.
    mkdru_insert($node);
  }
  else {
    drupal_write_record('mkdru', $node, 'vid');
  }
}

/**
 * Implements hook_node_revision_delete()
 */
function mkdru_node_revision_delete($node) {
  db_delete('mkdru')
    ->condition('vid', $node->vid)
    ->execute();
}

/**
 * Implements hook_delete()
 */
function mkdru_delete($node) {
  // Deleting by nid covers all revisions.
  db_delete('mkdru')
    ->condition('nid', $node->nid)
    ->execute();
}


// Node rendering
/**
* Implements hook_load()
*/
function mkdru_load($nodes) {
  $result = db_query('SELECT * FROM {mkdru} WHERE nid IN (:nids)', array(':nids' => array_keys($nodes)));
  foreach ($result as $record) {
    $nodes[$record->nid]->mkdru = $record;
  }
}

/**
* Implements hook_theme().
*/
function mkdru_theme() {
  return array(
    'mkdru_form' => array(
      'template' => 'mkdru-form',
      'variables' => array(),
    ),
    'mkdru_results' => array(
      'template' => 'mkdru-results',
      'variables' => array(),
    ),
    'mkdru_js' => array(
      'variables' => array('node' => NULL),
    ),
    'mkdru_block_search' => array(
      'template' => 'mkdru-block-search',
      'variables' => array('nid' => NULL, 'path' => NULL),
    ),
    'mkdru_block_facet' => array(
      'template' => 'mkdru-block-facet',
      'variables' => array('class' => NULL)
    )
  );
}

/**
* Theme function to include Javascript search client and deps
*/
function theme_mkdru_js(&$variables) {
  $path = drupal_get_path('module', 'mkdru');
  // Pazpar2 client library
  drupal_add_js(variable_get('pz2_js_path', 'pazpar2/js') . '/pz2.js', array(
    'type' => 'file', 'scope' => 'footer', 'defer' => TRUE, 'preprocess' => FALSE));
  // jQuery plugin for query string/history manipulation.
  drupal_add_library('system', 'jquery.bbq');
  drupal_add_js($path . '/mkdru.theme.js', array(
    'type' => 'file', 'scope' => 'footer', 'defer' => TRUE, 'preprocess' => FALSE));
  drupal_add_js($path . '/mkdru.client.js', array(
    'type' => 'file', 'scope' => 'footer', 'defer' => TRUE, 'preprocess' => FALSE));
  drupal_add_js(array('mkdru' => $variables['node']->mkdru), 'setting');
}

/** 
* Implements hook_view()
*/
function mkdru_view($node, $view_mode) {
  if ($view_mode == 'full') {
    $node->content['mkdru_js'] = array(
      '#markup' => theme('mkdru_js', array('node' => $node)), 
      '#weight' => 0,
    );
    $node->content['mkdru_form'] = array(
      '#markup' => theme('mkdru_form'), 
      '#weight' => 1,
    );
    $node->content['mkdru_results'] = array(
      '#markup' => theme('mkdru_results'), 
      '#weight' => 2,
    );
  }
  return $node;
}


// Blocks
/** 
* Implements hook_block_info()
*/
function mkdru_block_info() {
  // facet blocks
  $facets = variable_get('mkdru_facets');
  foreach ($facets as $facet) {
    // NB: block caching is redundant for static content
    $blocks['mkdru_facet_' . $facet]['info'] = "mkdru - $facet " . t('facet');
    $blocks['mkdru_facet_' . $facet]['cache'] = DRUPAL_NO_CACHE;
  }

  // search blocks
  $result = db_query("SELECT title, nid FROM {node} WHERE type = 'mkdru';");
  foreach($result as $node) {
    $blocks['mkdru_search_' . $node->nid]['info'] = 
        t('mkdru - search box for "' . $node->title . '"');
    $blocks['mkdru_sources']['cache'] = DRUPAL_NO_CACHE;
  };

  return $blocks;
}

/** 
* Implements hook_block_view()
*/
function mkdru_block_view($delta) {
  if (substr($delta, 0, 12) == 'mkdru_facet_') {
    $facet = substr($delta, 12);
    $block['subject'] = t(ucwords($facet));
    $block['content'] = theme('mkdru_block_facet',
                               array('class' => 'mkdru-facet-' . $facet));
    return $block;
  }
  elseif (substr($delta, 0, 13) == 'mkdru_search_') {
    $nid = substr($delta, 13);
    $block['content'] = theme('mkdru_block_search',
        array('nid' => $nid, 'path' => '/node/' . $nid));
    return $block;
  }
}