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

/**
* Implements hook_perm()
*/
function mkdru_perm() {
  return array('create metasearch interface', 'edit any metasearch interface', 'edit own metasearch interface');
}

/**
* Implements hook_access()
*/
function mkdru_access($op, $node, $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' => 'Pazpar2 Metasearch 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',
  );
  $items['ahah-mkdru-facet'] = array(
    'page callback' => 'mkdru_add_facet_callback',
    'access arguments' => array('create metasearch interface'),
    'type' => MENU_CALLBACK,
  );
  return $items;
}

/**
* Implements 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) {
function mkdru_settings_form(&$form_state) {
  if (isset($form_state['values']['settings'])) {
    $settings = $form_state['values']['settings'];
  }
  elseif (isset($form_state['build_info']['args']['settings'])) {
    $settings = $form_state['build_info']['args']['settings'];
  }
  else {
    $settings = variable_get('mkdru_defaults', NULL);
  }

  $form['#cache'] = TRUE;

  $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' => FALSE
  );
  $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_submit'),
      '#ahah' => array(
        'path' => 'ahah-mkdru-facet',
        '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'),
    '#submit' => array('mkdru_add_facet_submit'),
    '#ahah' => array(
      'path' => 'ahah-mkdru-facet',
      'wrapper' => 'mkdru-facets-form-wrapper',
    ),
  );
  return $form;
}

function mkdru_add_facet_submit($form, &$form_state) {
  $newfacet = $form_state['values']['new_facet']['canonical'];
  $form_state['values']['settings']['facets'][$newfacet] = NULL;
  $form_state['rebuild'] = TRUE;
  return $form_state['values'];
}

function mkdru_remove_facet_submit($form, &$form_state) {
  $delfacet = $form_state['clicked_button']['#mkdru facet'];
  if ($delfacet)
    unset($form_state['values']['settings']['facets'][$delfacet]);
}

function mkdru_add_facet_callback() {
  // Necessary to work with hook_form
  module_load_include('inc', 'node', 'node.pages');

  // Retrieve form from cache
  $form_state = array('storage' => NULL, 'submitted' => FALSE);
  $form_build_id = $_POST['form_build_id'];
  $form = form_get_cache($form_build_id, $form_state);

  // Run drupal_process_form to call submit handler and update $form_state
  $args = $form['#parameters'];
  $form_id = array_shift($args);
  $form_state['post'] = $form['#post'] = $_POST;
  $form['#programmed'] = $form['#redirect'] = FALSE;
  drupal_process_form($form_id, $form, $form_state);

  // Regenerate form so we can render the new facet part
  $form = drupal_rebuild_form($form_id, $form_state, $args, $form_build_id);

  // Choose subset of form to redraw.
  $facet_form = $form['settings']['facets'];
  // Prevent duplicate wrappers.
  unset($facet_form['#prefix'], $facet_form['#suffix']);
  $output = theme('status_messages') . drupal_render($facet_form);

  // Final rendering callback
  drupal_json(array('status' => TRUE, 'data' => $output));
}


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

  $form = drupal_retrieve_form('mkdru_settings_form', &$form_state);
  $type = node_get_types('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
}

/**
* Implements hook_insert().
*/
function mkdru_insert($node) {
  $record['nid'] =  $node->nid;
  $record['vid'] =  $node->vid;
  $record['settings'] =  json_encode($node->settings);
  drupal_write_record('mkdru', &$record);
}

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

/**
 * Implements hook_nodeapi().
 *
 * When a node revision is deleted, we need to remove the corresponding record
 * from our table. The only way to handle revision deletion is by implementing
 * hook_nodeapi().
 */
function mkdru_nodeapi(&$node, $op, $teaser, $page) {
  switch ($op) {
    case 'delete revision':
      db_query('DELETE FROM {mkdru} WHERE vid = %d', $node->vid);
      break;
  }
}

/**
 * Implements hook_delete().
 */
function mkdru_delete($node) {
  // Deleting by nid covers all revisions.
  db_query('DELETE FROM {mkdru} WHERE nid = %d', $node->nid);
}


// Node rendering
/**
* Implements hook_load()
*/
function mkdru_load($node) {
  return db_fetch_object(db_query('SELECT * FROM {mkdru} WHERE vid = %d', $node->vid));
}

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

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

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

/** 
* Implements hook_block()
*/
function mkdru_block($op='list', $delta='sources', $edit=array()) {
  switch ($op) {
    case 'list':
      $result = db_query("SELECT title, {mkdru}.nid as nid, settings FROM {node},{mkdru} WHERE {mkdru}.nid = {node}.nid;");
      while ($node = db_fetch_object($result)) {
        // search blocks
        $blocks['mkdru_search_' . $node->nid]['info'] = 
           t('mkdru - search box for "' . $node->title . '"');
        // 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'] = BLOCK_CACHE_GLOBAL;
        }
      };
      return $blocks;

    case 'view':
      if (preg_match('/^mkdru_facet_(.*)_(\d+)$/', $delta, $matches) > 0) {
        $facet = $matches[1];
        $nid = $matches[2];

        // this is rather spendy just to get the title, should really
        // be able to set a default title in op=list. will be cached though
        // so I suppose it's okay?
        $result = db_query("SELECT settings FROM {mkdru} WHERE nid = %d;", $nid);
        $settingsjson = db_fetch_object($result)->settings;
        $settings = json_decode($settingsjson, TRUE);
        if (isset($settings['facets'][$facet]['displayName'])) {
          $block['subject'] = $settings['facets'][$facet]['displayName'];
        }
        $block['content'] = theme('mkdru_block_facet', 'mkdru-facet-' . $facet);
      }
      else if (substr($delta, 0, 13) == 'mkdru_search_') {
        $nid = substr($delta, 13);
        $block['content'] = theme('mkdru_block_search', $nid, '/node/' . $nid);
      }
    return $block;
  }
}