ding_reservation.module

<?php

/**
 * @file
 * Handles display and creation/deletion of reservations for users.
 */

// Default interest period is ~six months.
define('DING_RESERVATION_DEFAULT_INTEREST_PERIOD', 90 * 86400);

/**
 * Implements hook_ctools_plugin_directory().
 *
 * It simply tells panels where to find the .inc files that define various
 * args, contexts, content_types. In this case the subdirectories of
 * ctools_plugin_example/panels are used.
 */
function ding_reservation_ctools_plugin_directory($module, $plugin) {
  if ($module == 'ctools' && !empty($plugin)) {
    return "plugins/$plugin";
  }
}

/**
 * Implements hook_menu().
 */
function ding_reservation_menu() {
  // @todo ding_reservation really doesn't know that this path is correct. How
  // to handle it?
  $items['user/%user/status/reservations/update/%'] = array(
    'title' => 'Update reservations',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('ding_reservation_update_reservations_form', 1, 5),
    'access callback' => 'ding_reservation_access',
    'access arguments' => array(1),
  );

  $items['user/%user/status/reservations/delete/%'] = array(
    'title' => 'Delete reservations',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('ding_reservation_delete_reservations_form', 1, 5),
    'access callback' => 'ding_reservation_access',
    'access arguments' => array(1),
  );

  $items['admin/config/ding/reservation'] = array(
    'title' => 'Ding reservation',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('ding_reservation_admin_settings_form'),
    'access arguments' => array('administer site configuration'),
    'file' => 'ding_reservation.admin.inc',
  );

  return $items;
}

/**
 * Access callback. Ensure that current user is the same.
 */
function ding_reservation_access($account) {
  global $user;
  return $user->uid == $account->uid;
}

/**
 * Implements hook_ding_entity_menu().
 */
function ding_reservation_ding_entity_menu(&$items, $type, $path, $index) {
  if ($type == 'ding_entity') {
    $items[$path . '/reserve'] = array(
      'title' => 'Reserve',
      'page callback' => 'ding_provider_get_form',
      'page arguments' => array('ding_reservation_reserve_form', $index),
      'access callback' => TRUE,
    );
  }
}

/**
 * Implements hook_ding_entity_buttons().
 */
function ding_reservation_ding_entity_buttons($type, $entity) {
  if ($type == 'ding_entity' && $entity->is('reservable')) {
    return array(ding_provider_get_form('ding_reservation_reserve_form', new DingReservationReservableEntity($entity), TRUE));
  }
}

/**
 * Implements hook_ding_provider_user().
 */
function ding_reservation_ding_provider_user() {
  return array(
    'reservation' => array(
      'required' => TRUE,
      'install time setup' => TRUE,
    ),
  );
}

/**
 * Implements hook_forms().
 *
 * If the forms listing ready and not ready for pickup reservations is listed
 * on the same page, they need to have different form ids in order for Drupal
 * to be able to tell which was submitted. As we're using one builder
 * function, use this to let have their own form id.
 */
function ding_reservation_forms($form_id, $args) {
  $forms['ding_reservation_reservations_ready_form'] = array(
    'callback' => 'ding_reservation_reservations_form',
  );
  $forms['ding_reservation_reservations_notready_form'] = array(
    'callback' => 'ding_reservation_reservations_form',
  );
  return $forms;
}

/**
 * Reserve form callback.
 *
 * Note that this form relies on form caching, which is triggered by
 * ajaxifying the submit button.
 */
function ding_reservation_reserve_form($form, &$form_state, $reservable, $hide_options = FALSE) {
  global $user;
  if (!($reservable instanceof DingReservationReservable)) {
    // Assume that we were given a reservable entity.
    $reservable = new DingReservationReservableEntity($reservable);
  }
  $entity = $reservable->getEntity();
  $uri = ding_entity_uri('ding_entity', $entity);

  // We post to our own path as we might want to rebuild the form.
  // @todo move *_get_destination to ding_base?
  if ($_GET['q'] != $uri['path'] . '/reserve') {
    $form['#action'] = url($uri['path'] . '/reserve', array('query' => ding_provider_get_destination()));
  }

  $form['reservable'] = array(
    '#type' => 'value',
    '#value' => $reservable,
  );

  $form['provider_options'] = array(
    '#type' => 'value',
    '#value' => array(),
  );

  $hide_options = !isset($form_state['options_hidden']) ? $hide_options : FALSE;
  $form_state['options_hidden'] = $hide_options;

  if (!$hide_options) {
    if (ding_provider_implements('reservation', 'options') && $provider_form = ding_provider_invoke('reservation', 'options', 'create', $user, $reservable)) {
      $form['provider_options'] = $provider_form + array(
        '#tree' => TRUE,
      );
    }
  }

  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Reserve'),
    '#ajax' => array(
      'callback' => 'ding_reservation_reserve_form_callback',
      'wrapper' => 'ding-reservation-reserve-form',
    ),
  );

  return $form;
}

/**
 * Form validation.
 */
function ding_reservation_reserve_form_validate($form, &$form_state) {
  global $user;
  if (ding_provider_implements('reservation', 'options_validate')) {
    $res = ding_provider_invoke('reservation', 'options_validate', 'create', $user, $form_state['values']['reservable'], $form_state['values']['provider_options']);
    /**
     * We cannot set the value of the individual provider form elements, as
     * they might not have been show, and thus not exist. However, setting the
     * value of the parent element to an associative array gives the same end
     * result.
     */
    $provider_options = array();
    foreach ($res as $key => $value) {
      if (is_array($value) && !empty($value['#error'])) {
        if (!$form_state['options_hidden']) {
          // Only show an error if the user had a choice.
          form_error($form['provider_options'], $res['#error']);
        }
        else {
          // Else simply rebuild the form.
          $form_state['rebuild'] = TRUE;
        }
      }
      else {
        $provider_options[$key] = $value;
      }
    }
    if (!empty($provider_options)) {
      form_set_value($form['provider_options'], $provider_options, $form_state);
    }
  }
}

/**
 * Form submission handler.
 */
function ding_reservation_reserve_form_submit($form, &$form_state) {
  global $user;
  if (ding_provider_implements('reservation', 'options_submit')) {
    ding_provider_invoke('reservation', 'options_submit', 'create', $user, $form_state['values']['reservable'], $form_state['values']['provider_options']);
  }
  if ($form_state['values']['reservable']) {
    $reservable = $form_state['values']['reservable'];
    try {
      $reservation_result = ding_provider_invoke('reservation', 'create', $user, $reservable->getProviderId(), $form_state['values']['provider_options']);
      $form_state['reserved'] = TRUE;
      // @todo use profile
      if (!empty($reservation_result['branch']) && ding_provider_implements('reservation', 'branch_name')) {
        $branch_name = ding_provider_invoke('reservation', 'branch_name', $reservation_result['branch']);
        drupal_set_message(t('"@title" reserved and will be available for pickup at @branch.', array('@title' => $reservable->getTitle(), '@branch' => $branch_name)));
      }
      else {
        drupal_set_message(t('"@title" reserved.', array('@title' => $reservable->getTitle())));
      }

      if (is_array($reservation_result) and !empty($reservation_result['queue_number'])) {
        drupal_set_message(t('You are number @number in queue.', array('@number' => $reservation_result['queue_number'])));
      }
    }
    catch (DingProviderUserException $e) {
      drupal_set_message($e->getMessageT(array('@title' => $reservable->getTitle())), 'error');
    }
    catch (DingProviderAuthException $e) {
      // Just rethrow.
      throw $e;
    }
    catch (Exception $e) {
      drupal_set_message(t('An error occurred while reserving item. Please try again later.'), 'error');
      watchdog('ding_reservation', 'Error while reserving, message: @message', array('@message', $e->getMessage()), WATCHDOG_ERROR);
    }
  }
}

/**
 * Ajax callback.
 */
function ding_reservation_reserve_form_callback($form, &$form_state) {
  global $user; 
  $response = array(
    '#type' => 'ajax',
    '#commands' => array(),
  );

  $html = theme('status_messages');
  if ($form_state['rebuild'] || form_get_errors()) {
    // Redisplay form.
    $html .= drupal_render($form);
  }

  $response['#commands'][] = ajax_command_ding_popup('ding_reservation', t('Reserve'), $html);
  $response['#commands'][] = ajax_command_append('.messages',
      '<div><button class="btn message-btn" onclick="jQuery(\'.ui-icon-closethick\').trigger(\'click\');">' . t("Ok") . '</button></div>');

  //update amount.
  $response['#commands'][] = ajax_command_html('#ding-user-reservation-amount .amount', '<span>(' . count(ding_provider_invoke_page('reservation', 'list', $user)) . ')</span>');
   
  return $response;
}

/**
 * Show a reservation list form.
 */
function ding_reservation_reservations_form($form, &$form_state, $items = array(), $type = 'not_ready_for_pickup') {
  drupal_add_library('system', 'ui.dialog');
  drupal_add_js(drupal_get_path('module', 'ding_reservation') . '/ding_reservation.js');
  drupal_add_css(drupal_get_path('theme', 'latto_odense') .'/css/oc_tablesort.css'); //tablesort overwrites.
  $options = array();
  $destination = drupal_get_destination();
  switch ($type) {
    case 'ready_for_pickup':
      $header = array(
        'title' => t('Title'),
        'notes' => t('periodical'),
        'created' => array('data' => t('Created date'),'class' => '{sorter: "ting_date_sort"}'),
        'pickup_date' => array('data' => t('Pickup date'),'class' => '{sorter: "ting_date_sort"}'),
        'pickup_branch' => t('Pickup branch'),
        'operations' => '',
      );
      uasort($items, 'ding_reservation_sort_queue_by_pickup_date');
    break;
    case 'not_ready_for_pickup':
      $header = array(
        'title' => t('Title'),
        'notes' => t('periodical'),
        'created' => array('data' => t('Created date'),'class' => '{sorter: "ting_date_sort"}'),
        'expiry' => array('data' => t('Expiry date'),'class' => '{sorter: "ting_date_sort"}'),
        'pickup_branch' => t('Pickup branch'),
        'queue_number' => t('Queue number'),
        'operations' => '',
      );
      uasort($items, 'ding_reservation_sort_queue_by_queue_number');
    break;
  }
  foreach ($items as $id => $item) {
    $entity = $item->entity;
    $pickup_branch = ding_provider_invoke('reservation', 'branch_name', $item->pickup_branch_id);
    switch ($type) {
    case 'ready_for_pickup':
      $res = NULL;
     //Check if remote loan then get title.
        if ($entity == FALSE) {
          $ding_entity_id = explode(":", $item->ding_entity_id);
          $result = ding_provider_invoke('availability', 'holdings', array($ding_entity_id[1]));
          $details = $result[$ding_entity_id[1]];      
          if (isset($details['title'])) {
          $title = array('#markup' =>'<h2>' . $details['title'] . '</h2>');
          }
        }
         elseif ($item->entity->type == 'Tidsskrift') {
          global $user;
          $notes = ding_provider_invoke('reservation', 'get_reservations', $user);
          $res   = $notes[$item->id];
          $title = array('#markup' => $item->display_name);
        }
        else {
          $title = array('#markup' => $item->display_name);
        }
      $options[$item->id] = array(
        'title' => array(
          'data' => array($entity ? ting_object_view($entity, 'user_list') : $title),
          'class' => 'title',
        ),
        'notes' => array(
          'data' => $res['notes'] ? check_plain($res['notes']) : '',
          'class' => 'notes',
        ),
        'created' => array(
          'data' => $item->created ? format_date(strtotime(check_plain($item->created)), 'date_only') : '',
          'class' => 'created-date',
        ),
        'pickup_date' => array(
          'data' => $item->pickup_date ? format_date(strtotime(check_plain($item->pickup_date)), 'date_only' ) : '',
          'class' => 'pickup-date',
        ),
        'pickup_branch' => array(
          'data' => $pickup_branch ? check_plain($pickup_branch) : '',
          'class' => 'pickup-branch',
        ),
        'operations' => array(
          'data' =>  array(
            '#prefix' => '<div class="delete-reservation">',
            '#suffix' => '</div><div id="reservation-delete-confirm-ready-branch"></div>',
            '#type' => 'submit',
            '#submit' => array('ding_reservation_reservation_delete_submit'),
            '#reservation_id' => $item->id,
            '#name' => 'delete-' . preg_replace('/\W/', '-', $item->id), // Need this for formAPI can tell buttons apart
            '#value' => t('Delete'),
            '#options' => array('query' => $destination),
            '#attributes' => array(
              'onclick' => 'Drupal.ding_reservation.delete_confirm(event, 1, '.$item->id.')'
            ),
          ),
          'class' => 'operations',
        ),
      );
      if (isset($item->pickup_order_id)) {
        $options[$item->id]['title']['data'][] = array(
          '#type' => 'markup',
          '#prefix' => '<p class="pickup-order-id">',
          '#markup' => t('(Pickup id: @pickup_id)', array('@pickup_id' => check_plain($item->pickup_order_id))),
          '#suffix' => '</p>',
        );
      }

      $form['reservations'] = array(
        '#type' => 'tableselect_form',
        '#header' => $header,
        '#options' => $options,
        '#empty' => t('No reservations ready for pickup'),
      );
      $form['reservations']['#attributes']['class'] = array('tablesorter','{sortlist: [[4,0]]}');
      break;
    case 'not_ready_for_pickup':
      $res = NULL;
     //Check if remote loan then get title.
        if ($entity == FALSE) {
          $ding_entity_id = explode(":", $item->ding_entity_id);
          $result = ding_provider_invoke('availability', 'holdings', array($ding_entity_id[1]));
          $details = $result[$ding_entity_id[1]];      
          if (isset($details['title'])) {
          $title = array('#markup' =>'<h2>' . $details['title'] . '</h2>');
          }
        }
        elseif ($item->entity->type == 'Tidsskrift') {
          global $user;
          $notes = ding_provider_invoke('reservation', 'get_reservations', $user);
          $res   = $notes[$item->id];
           $title = array('#markup' => $item->display_name );
        }
        else {
          $title = array('#markup' => $item->display_name);
        }
      $options[$item->id] = array(
        'title' => array(
          'data' => array($entity ? ting_object_view($entity, 'user_list') : $title),
          'class' => 'title',
        ),      
        'notes' => array(
          'data' => $res['notes'] ? check_plain($res['notes']) : '',
          'class' => 'notes',
        ),       
        'created' => array(
          'data' => $item->created ? format_date(strtotime(check_plain($item->created)), 'date_only') : '',
          'class' => 'created-date',
        ),
        'expiry' => array(
          'data' => $item->created ? format_date(strtotime(check_plain($item->expiry)), 'date_only') : '',
          'class' => 'expire-date',
        ),
        'pickup_branch' => array(
          'data' => $pickup_branch ? check_plain($pickup_branch) : '',
          'class' => 'pickup-branch',
        ),
        'queue_number' => array(
          'data' => $item->queue_number ? check_plain($item->queue_number) : '',
          'class' => 'queue-number',
        ),
        'operations' => array(
          'data' => array(
            '#prefix' => '<div class="delete-reservation">',
            '#suffix' => '</div><div id="reservation-delete-confirm-not-ready-branch"></div>',
            '#type' => 'submit',
            '#submit' => array('ding_reservation_reservation_delete_submit'),
            '#reservation_id' => $item->id,
            '#name' => 'delete-' . preg_replace('/\W/', '-', $item->id), // Need this for formAPI can tell buttons apart
            '#value' => t('Delete'),
            '#attributes' => array(
              'onclick' => 'Drupal.ding_reservation.delete_confirm(event, 0, '.$item->id.')'
            ),
            '#options' => array('query' => $destination),
          ),
          'class' => 'operations',
        ),
      );

      $form['reservations'] = array(
        '#type' => 'tableselect_form',
        '#header' => $header,
        '#options' => $options,
        '#empty' => t('No Reservations'),
      );
      $form['reservations']['#attributes']['class'] = array('tablesorter','{sortlist: [[6,0]]}');
      break;
    }
  }

  $form['delete'] = array(
    '#prefix' => '<div class="delete-reservations">',
    '#suffix' => '</div>',
    '#submit' => array('ding_reservation_deletes_form_submit'),
    '#type' => 'submit',
    '#value' => t('Delete reservations'),
    '#ajax' => array(
      'callback' => 'ding_reservation_deletes_form_callback',
      'wrapper' => 'ding-reservation-reservations-form',
    ),
  );

  if ($type == 'not_ready_for_pickup') {
    $form['update'] = array(
      '#prefix' => '<div class="update-reservations">',
      '#suffix' => '</div>',
      '#type' => 'submit',
      /* '#submit' => array('ding_reservation_update_reservation_form'), */
      '#submit' => array('ding_reservation_updates_form_submit'),
      '#value' => t('Update reservations'),
      '#ajax' => array(
        'callback' => 'ding_reservation_updates_form_callback',
        'wrapper' => 'ding-reservation-updates-form',
      ),
    );
  }

  
  return $form;
}

/**
 * Submit handler for the reservations form.
 */
function ding_reservation_reservation_delete_submit($form, &$form_state) {
  global $user;
  if (!empty($form_state['triggering_element']['#reservation_id'])) {
    $reservations = array($form_state['triggering_element']['#reservation_id']);
  }
  else {
    $reservations = array_filter($form_state['values']['reservations']);
  }
  foreach ($reservations as $entity_id) {
    ding_provider_invoke('reservation', 'delete', $user, $entity_id);
  }
}

/**
 * Submit handler for the delete form.
 */
function ding_reservation_deletes_form_submit($form, &$form_state) {
  global $user;
  $ids = join(',', array_map('rawurlencode', array_filter($form_state['values']['reservations'],'is_string')));
  $form_state['encoded_reservations'] = $ids;
  $form_state['redirect'] = array('user/' . $user->uid . '/status/reservations/delete/' . $ids, array('query' => drupal_get_destination()));
}

/**
 * Submit handler for the update form.
 */
function ding_reservation_updates_form_submit($form, &$form_state) {
  global $user;
  $ids = join(',', array_map('rawurlencode', array_filter($form_state['values']['reservations'],'is_string')));
  $form_state['encoded_reservations'] = $ids;
  $form_state['redirect'] = array('user/' . $user->uid . '/status/reservations/update/' . $ids, array('query' => drupal_get_destination()));
}

/**
 * Ajax callback for the delete form.
 */
function ding_reservation_deletes_form_callback($form, &$form_state) {
  global $user;
  $response = array(
    '#type' => 'ajax',
    '#commands' => array(),
  );

  $html = theme('status_messages');
  $html .= drupal_render(drupal_get_form('ding_reservation_delete_reservations_form', $user, $form_state['encoded_reservations']));

  if ($html) {
    $response['#commands'][] = ajax_command_ding_popup('ding_reservation', t('Delete reservations'), $html, array('refresh' => TRUE));
  }
  return $response;
}

/**
 * Ajax callback for the update form.
 */
function ding_reservation_updates_form_callback($form, &$form_state) {
  global $user;
  $response = array(
    '#type' => 'ajax',
    '#commands' => array(),
  );

  $html = theme('status_messages');
  $html .= drupal_render(drupal_get_form('ding_reservation_update_reservations_form', $user, $form_state['encoded_reservations']));

  if ($html) {
    $response['#commands'][] = ajax_command_ding_popup('ding_reservation', t('Update reservations'), $html, array('refresh' => TRUE));
  }
  return $response;
}

/**
 * Delete reservations form.
 */
function ding_reservation_delete_reservations_form($form, $form_state, $account, $reservation_ids) {
  global $user;
  $ids = array_map('rawurldecode', explode(',', $reservation_ids));

  $form_state['cache'] = TRUE;

  $form['reservations'] = array(
    '#type' => 'value',
    '#value' => $ids,
  );

  $form['confirm_text'] = array(
    '#markup' => '<div>' . t('Are you sure you want to delete these reservations?') . '</div>',
  );

  $form['submit'] = array(
    '#type' => 'submit',
    '#submit' => array('ding_reservation_delete_reservations_form_submit'),
    '#ajax' => array(
      'callback' => 'ding_reservation_delete_reservations_form_callback',
      'wrapper' => 'ding-reservation-delete-reservation-form',
    ),
    '#value' => t('Yes'),
    '#name' => 'delete_reservations',
  );

  $form['cancel'] = array(
    '#markup' => '<input type="button" onclick="location.href=\'/user/' . $user->uid . '/status/reservations\'; return false;" value="' . t("Cancel") . '" />',
  );

  return $form;
}

/**
 * Update reservations form.
 */
function ding_reservation_update_reservations_form($form, $form_state, $account, $reservation_ids) {
  global $user;
  $ids = array_map('rawurldecode', explode(',', $reservation_ids));

  $form_state['cache'] = TRUE;

  $form['reservations'] = array(
    '#type' => 'value',
    '#value' => $ids,
  );

  if (ding_provider_implements('reservation', 'options') && $provider_form = ding_provider_invoke('reservation', 'options', 'update', $user, NULL)) {
    $form['provider_options'] = $provider_form + array(
      '#tree' => TRUE,
    );
  }
  
  $form['submit'] = array(
    '#type' => 'submit',
    '#submit' => array('ding_reservation_update_reservations_form_submit'),
    '#ajax' => array(
      'callback' => 'ding_reservation_update_reservations_form_callback',
      'wrapper' => 'ding-reservation-update-reservation-form',
    ),
    '#value' => t('Update reservations'),
  );
  return $form;
}

/**
 * Validation handler.
 */
function ding_reservation_update_reservations_form_validate($form, &$form_state) {
  global $user;
  if (ding_provider_implements('reservation', 'options_validate')) {
    $res = ding_provider_invoke('reservation', 'options_validate', 'create', $user, $form_state['values']['reservations'], $form_state['values']['provider_options']);
    /**
     * We cannot set the value of the individual provider form elements, as
     * they might not have been show, and thus not exist. However, setting the
     * value of the parent element to an associative array gives the same end
     * result.
     */
    $provider_options = array();
    foreach ($res as $key => $value) {
      if (is_array($value) && !empty($value['#error'])) {
        if (!$form_state['options_hidden']) {
          // Only show an error if the user had a choice.
          form_error($form['provider_options'], $res['#error']);
        }
        else {
          // Else simply rebuild the form.
          $form_state['rebuild'] = TRUE;
        }
      }
      else {
        $provider_options[$key] = $value;
      }
    }
    if (!empty($provider_options)) {
      form_set_value($form['provider_options'], $provider_options, $form_state);
    }
  }
}

/**
 * Submit handlers.
 *
 */
function ding_reservation_delete_reservations_form_submit($form, &$form_state) {
  global $user;
  if (!empty($form_state['triggering_element']['#reservation_id'])) {
    $reservations = array($form_state['triggering_element']['#reservation_id']);
  }
  else {
    $reservations = array_filter($form_state['values']['reservations']);
  }
  foreach ($reservations as $entity_id) {
    ding_provider_invoke('reservation', 'delete', $user, $entity_id);
  }
}

function ding_reservation_update_reservations_form_submit($form, &$form_state) {
  global $user;
  ding_provider_invoke('reservation', 'update', $user, $form_state['values']['reservations'], $form_state['values']['provider_options']);
}

/**
 * Ajax callback functions.
 */
function ding_reservation_delete_reservations_form_callback($form, &$form_state) {
  $response = array(
    '#type' => 'ajax',
    '#commands' => array(),
  );

  $html = theme('status_messages') . t('Your reservations have been deleted.');
  $response['#commands'][] = ajax_command_ding_popup('ding_reservation', t('Delete reservations'), $html, array('refresh' => TRUE));

  return $response;
}

function ding_reservation_update_reservations_form_callback($form, &$form_state) {
  $response = array(
    '#type' => 'ajax',
    '#commands' => array(),
  );

  $html = theme('status_messages') . t('Your reservations has been updated.');
  $response['#commands'][] = ajax_command_ding_popup('ding_reservation', t('Update reservations'), $html, array('refresh' => TRUE));

  return $response;
}

/**
 * Default options handling.
 *
 * Reservation providers may use these to use standard implementations of
 * widgets like pickup branch and get much logic for free.
 */

/**
 * Create a pickup branch selector.
 *
 * Returns form element(s) for selecting a pickup branch.
 */
function ding_reservation_default_options_branch($type, $name, $default, $options) {
  $create = ($type == 'create');
  $allowed_branches = ($create ? array() : array('' => t('No change'))) + $options;
  $default_value = $create ? $default : '';
  $form[$name] = array(
    '#type' => 'select',
    '#title' => t('Select branch'),
    '#options' => $allowed_branches,
    '#default_value' => $default_value,
  );
  if ($create) {
    $form[$name . 'description'] = array(
      '#markup' => '<p>' . t('In order to make quick reservations, you must select a default pickup branch.') . '</p>',
    );
  }
  return $form;
}


/**
 * Create an interest period selector.
 *
 * Returns form element(s) for selecting an interest period.
 */
function ding_reservation_interest_period_selector($type, $name, $default, $options) {
  $create = ($type == 'create');
  $allowed_periods = ($create ? array() : array('' => t('No change'))) + $options;
  // $default_value = $create ? $default : '';
  $form[$name] = array(
    '#type' => 'select',
    '#title' => t('Select interest period'),
    '#options' => $allowed_periods,
    '#default_value' => $default,
  );
  if ($create) {
    $form[$name . 'description'] = array(
      '#markup' => '<p>' . t('Select an interest period.') . '</p>',
    );
  }
  return $form;
}


/**
 * Validate pickup branch selector.
 *
 * Returns what ding_reservation expects.
 */
function ding_reservation_default_options_branch_validate($type, $name, $default, $values) {
  if (empty($values[$name])) {
    if ($type == 'create' && (empty($default) || variable_get('ding_reservation_always_choose_pickup', FALSE))) {
      $result['openruth_preferred_branch'] = array(
        '#error' => 'You must select a branch',
      );
    }
    else {
      $result[$name] = $default;
    }
    return $result;
  } else {
    return $values;
  }
}

/**
 * Submit pickup branch selector.
 *
 * Returns new properties to save, if any.
 */
function ding_reservation_default_options_branch_submit($type, $name, $default, $values) {
  $result = array();
  if ($type == 'create' && !empty($values[$name]) && $values[$name] != $default) {
    $result[$name] = $values['name'];
  }
  return $result;
}


/**
 * Callback function to sort array by pickup date
 */
function ding_reservation_sort_queue_by_pickup_date($a, $b) {
  if ($a->pickup_date == $b->pickup_date) {
    return 0;
  }
  return ($a->pickup_date < $b->pickup_date) ? -1 : 1;
}

/**
 * Callback function for sorting loans by queue_number
 */
function ding_reservation_sort_queue_by_queue_number($a, $b) {
  if ($a->queue_number == $b->queue_number) {
    return 0;
  }
  return ($a->queue_number < $b->queue_number) ? -1 : 1;
}

/**
 * Interface for reservable items.
 */
interface DingReservationReservable {
  public function getProviderId();
  // @todo, this should be optional.
  public function getEntity();
  public function getTitle();
}

/**
 * A reservable entity.
 */
class DingReservationReservableEntity implements DingReservationReservable {
  public function __construct($entity) {
    $this->entity = $entity;
  }

  public function getProviderId() {
    return $this->entity->provider_id;
  }

  public function getEntity() {
    return $this->entity;
  }
  public function getTitle() {
    return $this->entity->title;
  }
}