<?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) {
  theme('mkdru_js', array('setting' => array('mkdru' => array(
    'settings' => json_encode(variable_get('mkdru_ding', NULL)),
    'query' => $keys))));
  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/config/search/mkdru'] = array(
    'title' => 'Configure Pazpar2 metasearch integration',
    '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',
  );
  $items['admin/config/search/mkdru_ding'] = array(
    'title' => 'Pazpar2 Metasearch Ding Integration',
    'description' => 'Search settings for mkdru instance integrated into Ding.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('mkdru_ding_settings'),
    'access arguments' => array('administer site configuration'),
    'type' => MENU_NORMAL_ITEM,
  );
  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');
}


// Config form common to node and settings
function mkdru_settings_form($form, &$form_state) {
  if (isset($form_state['values']['settings'])) {
    $settings = $form_state['values']['settings'];
  }
  else if (isset($form_state['build_info']['args']['settings'])) {
    $settings = $form_state['build_info']['args']['settings'];
  }
  else {
    $settings = variable_get('mkdru_defaults');
  }

  $form['settings'] = array(
    '#tree' => TRUE,
  );

  $form['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' => $settings['pz2_path'],
  );
  $form['settings']['use_sessions'] = array(
    '#type' => 'checkbox',
    '#title' => t('Session handling'),
    '#description' => t('Disable for use with Service Proxy'),
    '#default_value' => $settings['use_sessions'],
  );

  $form['settings']['sp']  = array(
    '#type' => 'fieldset',
    '#title' => t('Service Proxy specific settings'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE
  );
  $form['settings']['sp']['user'] = array(
    '#type' => 'textfield',
    '#title' => t('Service Proxy username'),
    '#description' => t('Service Proxy username'),
    '#required' => FALSE,
    '#default_value' => $settings['sp']['user'],
  );
  $form['settings']['sp']['pass'] = array(
    '#type' => 'textfield',
    '#title' => t('Service Proxy password'),
    '#description' => t('Service Proxy password'),
    '#required' => FALSE,
    '#default_value' => $settings['sp']['pass'],
  );

  $form['settings']['facets']  = array(
    '#type' => 'fieldset',
    '#title' => t('Facet settings'),
    // Set up the wrapper so that AJAX will be able to replace the fieldset.
    '#prefix' => '<div id="mkdru-facets-form-wrapper">', 
    '#suffix' => '</div>',
    '#collapsible' => TRUE,
    '#collapsed' => FALSE
  );

  foreach (array_keys($settings['facets']) as $facet) {
    $form['settings']['facets'][$facet]  = array(
      '#type' => 'fieldset',
      '#title' => $facet . ' ' . t('facet'),
      '#collapsible' => TRUE,
      '#collapsed' => FALSE
    );
    $form['settings']['facets'][$facet]['displayName'] = array(
      '#type' => 'textfield',
      '#title' => t('Facet name to display in UI'),
      '#required' => TRUE,
      '#default_value' => $settings['facets'][$facet]['displayName'],
    );
    $form['settings']['facets'][$facet]['pz2Name'] = array(
      '#type' => 'textfield',
      '#title' => t('Name of termlist in Pazpar2'),
      '#required' => TRUE,
      '#default_value' => $settings['facets'][$facet]['pz2Name'],
    );
    $form['settings']['facets'][$facet]['limiter'] = array(
      '#type' => 'textfield',
      '#title' => t('Query limiter string'),
      '#default_value' => $settings['facets'][$facet]['limiter'],
      '#size' => 5,
    );
    $form['settings']['facets'][$facet]['multiLimit'] = array(
      '#type' => 'checkbox',
      '#title' => t('Allow multiple limits?'),
      '#default_value' => $settings['facets'][$facet]['multiLimit'],
    );
    $form['settings']['facets'][$facet]['max'] = array(
      '#type' => 'textfield',
      '#title' => t('Number of terms to display'),
      '#required' => TRUE,
      '#default_value' => $settings['facets'][$facet]['max'],
      '#size' => 3,
      '#maxlength' => 3,
    );
    $form['settings']['facets'][$facet]['orderWeight'] = array(
      '#type' => 'textfield',
      '#title' => t('Facet weight'),
      '#default_value' => $settings['facets'][$facet]['orderWeight'],
      '#size' => 3,
      '#maxlength' => 3,
    );
    $form['settings']['facets'][$facet]['remove'] = array(
      '#type' => 'submit',
      '#value' => t('Remove ') . $facet . t(' facet'),
      '#mkdru facet' => $facet,
      '#submit' => array('mkdru_remove_facet'),
      '#ajax' => array(
        'callback' => 'mkdru_ajax_facet_callback',
        'wrapper' => 'mkdru-facets-form-wrapper',
      ),
    );
  }

  $form['new_facet']  = array(
    '#type' => 'fieldset',
    '#title' => t('Add new facet...'),
    '#tree' => TRUE,
    '#collapsible' => TRUE,
    '#collapsed' => FALSE
  );
  $form['new_facet']['canonical'] = array(
    '#type' => 'textfield',
    '#title' => t('Canonical name of new facet'),
  );
  $form['new_facet']['button'] = array(
    '#type' => 'submit',
    '#value' => t('Add facet'),
    '#description' => t('Configure additional facets based on Pazpar2/SP termlists'),
    '#weight' => 1,
    '#submit' => array('mkdru_add_facet_form'),
    '#ajax' => array(
      'callback' => 'mkdru_ajax_facet_callback', 
      'wrapper' => 'mkdru-facets-form-wrapper',
    ),
  );
  return $form;
}

function mkdru_add_facet_form($form, &$form_state) {
  // TODO: validation
  $newfacet = $form_state['values']['new_facet']['canonical'];
  $form_state['values']['settings']['facets'][$newfacet] = NULL;
  $form_state['rebuild'] = TRUE;
}

function mkdru_remove_facet($form, &$form_state) {
  $delfacet = $form_state['clicked_button']['#mkdru facet'];
  if ($delfacet)
    unset($form_state['values']['settings']['facets'][$delfacet]);
  // Block table is not rebuilt like in D6 so we need to remove blocks explicitly
  // This is a bit preemptive but the block still reappears in block_list if you
  // decide not to save the facet deletion.
  db_delete('block')->condition(db_and()
    ->condition('module', 'mkdru')
    ->condition('delta', 'mkdru_facet_' . $delfacet . '_' . $form_state['values']['nid'])
    )->execute();
  $form_state['rebuild'] = TRUE;
}

function mkdru_ajax_facet_callback($form, &$form_state) {
  return $form['settings']['facets'];
}


// Ding config
function mkdru_ding_settings($form, &$form_state) {
  $form_state['build_info']['args']['settings'] = variable_get('mkdru_ding', NULL);
  $form = drupal_retrieve_form('mkdru_settings_form', $form_state);
  $form['settings']['#title'] = t('Search settings for DING integration');
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Save configuration',
  );
  return $form;
}

function mkdru_ding_settings_submit($form, &$form_state) {
  variable_set('mkdru_ding', $form_state['values']['settings']);
  drupal_set_message(t('The configuration options have been saved.'));
}


// Node config
/**
* Implements hook_form()
*/
function mkdru_form(&$node, &$form_state) {
  if (isset($node->mkdru->settings)) {
    // Second decode parameter indicates associative array
    $form_state['build_info']['args']['settings'] = json_decode($node->mkdru->settings, TRUE);
  }
  $form = drupal_retrieve_form('mkdru_settings_form', $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
  );
  return $form;
}

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

/**
* Implements hook_insert().
*/
function mkdru_insert($node) {
  $fields = array('nid' => $node->nid, 'vid' => $node->vid,
            'settings' => json_encode($node->settings));
  db_insert('mkdru')->fields($fields)->execute();
}

/**
* Implements hook_update().
*/
function mkdru_update($node) {
  if ($node->revision) {
    // New revision; treat it as a new record.
    mkdru_insert($node);
  }
  else {
    db_update('mkdru')
      ->condition('vid', $node->vid)
      ->fields(array('settings' => json_encode($node->settings)))
      ->execute();
    block_flush_caches();
  }
}

/**
 * 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();
  // Block table is not rebuilt like in D6 so we need to remove blocks explicitly
  db_delete('block')->condition(db_and()
    ->condition('module', 'mkdru')
    ->condition('delta', '%\_' . $node->nid, 'like')
    )->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('setting' => 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) {
  $path = drupal_get_path('module', 'mkdru');
  // Pazpar2 client library
  drupal_add_js(variable_get('pz2_js_path', 'pazpar2/js') . '/pz2.js', array(
    'type' => 'external', 'scope' => 'footer', 'defer' => TRUE, 'preprocess' => FALSE));
  // jQuery plugin for query string/history manipulation.
  drupal_add_library('system', 'jquery.bbq');
  drupal_add_js($path . '/mkdru.theme.js', array(
    'type' => 'file', 'scope' => 'footer', 'defer' => TRUE, 'preprocess' => FALSE));
  drupal_add_js($path . '/mkdru.client.js', array(
    'type' => 'file', 'scope' => 'footer', 'defer' => TRUE, 'preprocess' => FALSE));
  drupal_add_js($variables['setting'], 'setting');
}

/** 
* Implements hook_view()
*/
function mkdru_view($node, $view_mode) {
  if ($view_mode == 'full') {
    $node->content['mkdru_js'] = array(
      '#markup' => theme('mkdru_js', array('setting' 
        => array('mkdru' => array('settings' => $node->mkdru->settings)))),
      '#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() {
  $blocks = array();
  $result = db_query("SELECT title, {mkdru}.nid as nid, settings FROM {node},{mkdru} WHERE {mkdru}.nid = {node}.nid;");
  foreach($result as $node) {
    // search blocks
    $blocks['mkdru_search_' . $node->nid]['info'] = 
        t('mkdru - search box for "' . $node->title . '"');
    $blocks['mkdru_search_' . $node->nid]['cache'] = DRUPAL_NO_CACHE;
    // facet blocks
    $settings = json_decode($node->settings, TRUE);
    foreach ($settings['facets'] as $facet_name => $facet) {
      $key = 'mkdru_facet_' . $facet_name . '_' . $node->nid;
      $blocks[$key]['info'] = 'mkdru - ' . $facet_name
        . t(' facet for "') . $node->title . '"';
      $blocks[$key]['visibility'] = 1;
      $blocks[$key]['pages'] = 'node/' . $node->nid;
      $blocks[$key]['cache'] = DRUPAL_CACHE_GLOBAL;
    }
  };
  return $blocks;
}

/** 
* Implements hook_block_view()
*/
function mkdru_block_view($delta) {
  if (substr($delta, 0, 13) == 'mkdru_search_') {
    $nid = substr($delta, 13);
    $block['content'] = theme('mkdru_block_search',
      array('nid' => $nid, 'path' => '/node/' . $nid));
    return $block;
  }
  else if (preg_match('/^mkdru_facet_(.*)_(\d+)$/', $delta, $matches) > 0) {
    $facet = $matches[1];
    $nid = $matches[2];
    $result = db_query("SELECT settings FROM {mkdru} WHERE nid = :nid;", array(':nid' => $nid));
    $settingsjson = $result->fetchObject()->settings;
    $settings = json_decode($settingsjson, TRUE);
    if (isset($settings['facets'][$facet]['displayName'])) {
      $block['subject'] = $settings['facets'][$facet]['displayName'];
    }
    $block['content'] = theme('mkdru_block_facet', array('class' => 'mkdru-facet-' . $facet));
    return $block;
  }
}