pbs_tv_schedule.module

<?php

/**
 * @file
 * Core functions and hooks for the PBS TV Schedule module.
 */

const PBS_TV_SCHEDULE_SHOW_ID_NONE = 'noshowid';

/**
 * Implements hook_menu().
 *
 * @see pbs_tv_schedule_date_load()
 */
function pbs_tv_schedule_menu() {
  $items = array();

  $items['pbs-tv-schedule/schedule'] = array(
    'title' => 'Schedule',
    'description' => 'Date-based schedule page.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('pbs_tv_schedule_schedule'),
    'access arguments' => array('access content'),
    'type' => MENU_SUGGESTED_ITEM,
  );

  $items['pbs-tv-schedule/schedule/week'] = array(
    'title' => 'Week-based schedule page,',
    'page callback' => 'pbs_tv_schedule_schedule_week',
    'access arguments' => array('access content'),
    'type' => MENU_SUGGESTED_ITEM,
  );

  $items['pbs-tv-schedule/upcoming/nojs'] = array(
    'page callback' => 'pbs_tv_schedule_upcoming',
    'page arguments' => array(2),
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );
  $items['pbs-tv-schedule/upcoming/ajax'] = array(
    'delivery callback' => 'ajax_deliver',
  ) + $items['pbs-tv-schedule/upcoming/nojs'];

  $items['admin/config/system/pbs-tv-schedule'] = array(
    'title' => 'PBS TV Schedule',
    'description' => 'PBS TV Schedule settings.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('pbs_tv_schedule_settings'),
    'access arguments' => array('administer pbs tv schedule'),
    'file' => 'pbs_tv_schedule.admin.inc',
  );

  $items['pbs-tv-schedule/autocomplete/program'] = array(
    'title' => 'Autocomplete for programs',
    'page callback' => '_pbs_tv_schedule_autocomplete_program',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );

  return $items;
}

/**
 * Implements hook_help().
 */
function pbs_tv_schedule_help($path, $arg) {
  switch ($path) {
    case 'admin/help#pbs_tv_schedule':
      $output = file_get_contents(
        drupal_get_path('module', 'pbs_tv_schedule') . '/README.md'
      );
      if (module_exists('markdown')) {
        $output = filter_xss_admin(module_invoke(
          'markdown',
          'filter',
          'process',
          0,
          -1,
          $output
        ));
      }
      else {
        $output = '<pre>' . check_plain($output) . '</pre>';
      }
      return $output;
  }
}

/**
 * Implements hook_permission().
 */
function pbs_tv_schedule_permission() {
  return array(
    'administer pbs tv schedule' => array(
      'title' => t('Administer PBS TV Schedule settings.'),
    ),
  );
}

/**
 * Implements hook_theme().
 */
function pbs_tv_schedule_theme() {
  $module_path = drupal_get_path('module', 'pbs_tv_schedule');
  $path = $module_path . '/theme';
  return array(
    'pbs_tv_schedule_schedule' => array(
      'render element' => 'form',
      'template' => 'pbs-tv-schedule-schedule',
      'file' => 'theme.inc',
      'path' => $path,
    ),
    'pbs_tv_schedule_schedule_week_filter' => array(
      'render element' => 'form',
      'template' => 'pbs-tv-schedule-schedule-week-filter',
      'file' => 'theme.inc',
      'path' => $path,
    ),
    'pbs_tv_schedule_schedule_date' => array(
      'template' => 'pbs-tv-schedule-schedule-date',
      'variables' => array(
        'date' => '',
        'items' => array(),
      ),
      'file' => 'theme.inc',
      'path' => $path,
    ),
    'pbs_tv_schedule_schedule_search' => array(
      'template' => 'pbs-tv-schedule-schedule-search',
      'variables' => array(
        'program' => '',
        'items' => array(),
      ),
      'file' => 'theme.inc',
      'path' => $path,
    ),
    'pbs_tv_schedule_schedule_date_item' => array(
      'template' => 'pbs-tv-schedule-schedule-date-item',
      'variables' => array(
        'feed' => '',
        'show_id' => '',
        'start_time' => '',
        'title' => '',
        'subtitle' => '',
        'description' => '',
        'parent_description' => '',
        'duration' => 0,
        'closed_captions' => FALSE,
        'hd' => FALSE,
        'stereo' => FALSE,
        'animated' => FALSE,
        'upcoming_url' => '',
        'listing' => array(),
      ),
      'file' => 'theme.inc',
      'path' => $path,
    ),
    'pbs_tv_schedule_schedule_week' => array(
      'template' => 'pbs-tv-schedule-schedule-week',
      'variables' => array(
        'title' => '',
        'link_previous' => NULL,
        'link_next' => NULL,
        'headers' => array(),
        'rows' => array(),
      ),
      'file' => 'theme.inc',
      'path' => $path,
    ),
    'pbs_tv_schedule_schedule_week_item' => array(
      'template' => 'pbs-tv-schedule-schedule-week-item',
      'variables' => array(
        'show_id' => '',
        'title' => '',
        'subtitle' => '',
        'description' => '',
        'duration' => 0,
        'closed_captions' => FALSE,
        'hd' => FALSE,
        'stereo' => FALSE,
        'animated' => FALSE,
        'flex_basis' => 0,
        'listing' => array(),
      ),
      'file' => 'theme.inc',
      'path' => $path,
    ),
    'pbs_tv_schedule_schedule_no_results' => array(
      'template' => 'pbs-tv-schedule-schedule-no-results',
      'variables' => array(
        'message' => t('No results found.'),
      ),
      'file' => 'theme.inc',
      'path' => $path,
    ),
    'pbs_tv_schedule_settings' => array(
      'render element' => 'form',
    ),
  );
}

/**
 * Implements hook_views_api().
 */
function pbs_tv_schedule_views_api() {
  return array(
    'api' => 3.0,
    'path' => drupal_get_path('module', 'pbs_tv_schedule') . '/includes/views',
  );
}

/**
 * Initiate a new API client instance.
 *
 * @param string $api_key
 *   The API key to use for the client (defaults to system variable).
 * @param string $call_sign
 *   The call sign to use for the client (defaults to system variable).
 * @param bool $use_cache
 *   Whether or not to use/create cached responses with this client.
 *
 * @return PbsTvScheduleClient
 *   TVSS API client.
 *
 * @see PbsTvScheduleClient
 */
function pbs_tv_schedule_get_api_client($api_key = NULL, $call_sign = NULL, $use_cache = TRUE) {
  if (empty($api_key)) {
    $api_key = variable_get('pbs_tv_schedule_api_key');
  }
  if (empty($call_sign)) {
    $call_sign = variable_get('pbs_tv_schedule_call_sign');
  }
  module_load_include('inc', 'pbs_tv_schedule', 'classes/PbsTvScheduleClient');
  $client = new PbsTvScheduleClient($api_key, $call_sign, $use_cache);
  return $client;
}

/**
 * Display date-based schedule page.
 *
 * This page also handles Program based search on the full schedule.
 */
function pbs_tv_schedule_schedule($form, &$form_state) {
  $base_path = drupal_get_path('module', 'pbs_tv_schedule');
  $form['#attached'] = array(
    'css' => array($base_path . '/css/pbs_tv_schedule.css'),
    'js' => array($base_path . '/js/pbs_tv_schedule.js'),
  );

  $date = _pbs_tv_schedule_filter_get_date();
  $date_default = $date->format('Y-m-d');
  try {
    $date->sub(new DateInterval('P7D'));
  }
  catch (Exception $e) {
    watchdog_exception('pbs_tv_schedule', $e);
  }

  $date_options = array();
  $today = new DateTime();
  for ($i = 0; $i < 13; $i++) {
    try {
      $date->add(new DateInterval('P1D'));
      $key = $date->format('Y-m-d');
      $value = $date->format('D, M. j');

      if ($key == $today->format('Y-m-d')) {
        $value = t('@date (today)', array('@date' => $value));
      }

      $date_options[$key] = $value;

    }
    catch (Exception $e) {
      watchdog_exception('pbs_tv_schedule', $e);
    }
  }
  $form['date'] = array(
    '#type' => 'select',
    '#title' => 'Date',
    '#options' => $date_options,
    '#default_value' => $date_default,
  );
  if (isset($form_state['values']['date'])) {
    $form['date']['#default_value'] = $form_state['values']['date'];
  }

  /* @var PbsTvScheduleClient $client */
  $client = pbs_tv_schedule_get_api_client(
    variable_get('pbs_tv_schedule_api_key'),
    variable_get('pbs_tv_schedule_call_sign')
  );
  $form_state['storage']['client'] = $client;

  $form['channel'] = _pbs_tv_schedule_channel_filter();
  if (isset($form_state['values']['channel'])) {
    $form['channel']['#default_value'] = $form_state['values']['channel'];
  }

  $form['program'] = array(
    '#type' => 'textfield',
    '#title' => t('Search by Program'),
    '#autocomplete_path' => 'pbs-tv-schedule/autocomplete/program',
    '#default_value' => '',
    '#attributes' => array(
      'placeholder' => t('Enter a program name...'),
    ),
  );
  if (isset($_GET['program'])) {
    $form['program']['#default_value'] = $_GET['program'];
  }
  if (isset($form_state['values']['program'])) {
    $form['program']['#default_value'] = $form_state['values']['program'];
  }

  $form['actions']['submit'] = array(
    '#type' => 'submit',
    '#value' => t('View'),
    '#ajax' => array(
      'callback' => '_pbs_tv_schedule_schedule_update',
      'progress' => array(
        'type' => 'throbber',
        'message' => t('Updating schedule...'),
      ),
    ),
  );

  $form['actions']['reset'] = array(
    '#type' => 'submit',
    '#value' => t('Reset'),
    '#submit' => array('pbs_tv_schedule_schedule_reset'),
  );

  $form['schedule'] = pbs_tv_schedule_schedule_results($form, $client);

  return $form;
}

/**
 * Submit handler for pbs_tv_schedule_schedule().
 *
 * @see pbs_tv_schedule_schedule()
 */
function pbs_tv_schedule_schedule_submit($form, &$form_state) {
  // Attempt to format any type of date. This is useful in situations where a
  // site overrides the default date select element (e.g. with date_popup).
  $date = &$form_state['values']['date'];
  $time = FALSE;
  if (is_array($date)) {
    if (isset($date['date'])) {
      $time = strtotime($date['date']);
    }
  }
  else {
    $time = strtotime($date);
  }
  if (!$time) {
    $time = time();
  }
  $date = date('Y-m-d', $time);

  $form_state['rebuild'] = TRUE;
}

/**
 * Reset handler for pbs_tv_schedule_schedule().
 *
 * @see pbs_tv_schedule_schedule()
 */
function pbs_tv_schedule_schedule_reset($form, &$form_state) {
  $form_state['rebuild'] = FALSE;
}

/**
 * AJAX handler for pbs_tv_schedule_schedule().
 *
 * Updates the date schedule results and page URL based on form values.
 *
 * @return array
 *   Updated schedule results element.
 */
function _pbs_tv_schedule_schedule_update($form, $form_state) {
  $commands = array();
  $element = pbs_tv_schedule_schedule_results(
    $form,
    $form_state['storage']['client']
  );
  $commands[] = ajax_command_html(
    '#pbs-tv-schedule-schedule-results',
    render($element)
  );
  $commands[] = array(
    'command' => 'pbsTvScheduleUpdateScheduleUri',
    'values' => $form_state['values'],
  );

  return array('#type' => 'ajax', '#commands' => $commands);
}

/**
 * Build schedule data results for the form.
 *
 * @param array $form
 *   Current form element.
 * @param PbsTvScheduleClient $client
 *   TVSS API client for program search.
 *
 * @return array
 *   Schedule results element for the form.
 *
 * @see pbs_tv_schedule_schedule()
 */
function pbs_tv_schedule_schedule_results(array $form, PbsTvScheduleClient $client) {
  $date = DateTime::createFromFormat('Y-m-d', $form['date']['#default_value']);
  $feed = $form['channel']['#default_value'];
  $program = $form['program']['#default_value'];

  $element = array(
    '#tree' => TRUE,
    '#prefix' => '<div id="pbs-tv-schedule-schedule-results">',
    '#suffix' => '</div>',
  );
  try {
    // If a program search term has been set, provide search results instead of
    // a specific date schedule.
    if (!empty($program)) {
      $listings = pbs_tv_schedule_program_upcoming_episodes($program, $client, $feed);
      $response[$feed] = array('listings' => $listings);
      $element['results'] = array(
        '#theme' => 'pbs_tv_schedule_schedule_search',
        '#program' => $program,
        '#items' => array(),
      );
    }
    else {
      $response = $client->getFullDay($date->format('Ymd'));
      $element['results'] = array(
        '#theme' => 'pbs_tv_schedule_schedule_date',
        '#date' => $date,
        '#items' => array(),
      );
    }
  }
  catch (PbsTvScheduleClientException $e) {
    watchdog_exception('pbs_tv_schedule', $e);
    $element['results'] = array(
      '#theme' => 'pbs_tv_schedule_schedule_no_results',
      '#message' => t('An error occurred. Please try again later.'),
    );
    return $element;
  }

  foreach ($response[$feed]['listings'] as $listing) {
    _pbs_tv_schedule_format_listing($listing);

    if (isset($listing['day'])) {
      $date = DateTime::createFromFormat('Ymd', $listing['day']);
    }

    $date->setTime(
      substr($listing['start_time'], 0, 2),
      substr($listing['start_time'], 2, 2)
    );

    $upcoming_url = url(
      'pbs-tv-schedule/upcoming/nojs',
      array(
        'query' => array(
          'show_id' => $listing['show_id'],
          'feed' => $feed,
          'after' => $date->format('YmdHi'),
        ),
      )
    );

    $element['results']['#items'][] = array(
      '#theme' => 'pbs_tv_schedule_schedule_date_item',
      '#feed' => $feed,
      '#show_id' => $listing['show_id'],
      '#start_time' => DateTimeImmutable::createFromMutable($date),
      '#title' => $listing['title'],
      '#subtitle' => $listing['subtitle'],
      '#description' => $listing['description'],
      '#parent_description' => $listing['parent_description'],
      '#duration' => $listing['minutes'],
      '#closed_captions' => $listing['closed_captions'],
      '#hd' => $listing['hd'],
      '#stereo' => $listing['stereo'],
      '#animated' => $listing['animated'],
      '#upcoming_url' => $upcoming_url,
      '#listing' => $listing,
    );
  }

  if (empty($element['results']['#items'])) {
    $element['results'] = array(
      '#theme' => 'pbs_tv_schedule_schedule_no_results',
    );

    if (!empty($program)) {
      $element['results']['#message'] = t(
        'No results found for %program.',
        array('%program' => $program)
      );
    }
  }

  return $element;
}

/**
 * Channel filter select element.
 *
 * Accounts for module configuration with default overridable by by a URL
 * parameter.
 *
 * @return array
 *   Select form element with channel options.
 *
 * @see pbs_tv_schedule_settings()
 */
function _pbs_tv_schedule_channel_filter() {
  $feeds = pbs_tv_schedule_get_feeds();
  uasort($feeds, 'drupal_sort_weight');
  $feed_options = array();

  foreach ($feeds as $feed) {
    if (isset($feed['enabled']) && !$feed['enabled']) {
      continue;
    }
    $feed_options[$feed['short_name']] = $feed['full_name'];
  }

  $feed_default = variable_get(
    'pbs_tv_schedule_feed_default',
    key($feed_options)
  );
  if (isset($_GET['channel'])) {
    $feed_default = $_GET['channel'];
  }

  return array(
    '#type' => 'select',
    '#title' => t('Channel'),
    '#options' => $feed_options,
    '#default_value' => $feed_default,
  );
}

/**
 * Gets an array of feeds with config data merged in, if available.
 *
 * @return array
 *   Feed information and configuration keyed by feed short name.
 *
 * @see pbs_tv_schedule_settings()
 */
function pbs_tv_schedule_get_feeds() {
  /* @var PbsTvScheduleClient $client */
  $client = pbs_tv_schedule_get_api_client(
    variable_get('pbs_tv_schedule_api_key'),
    variable_get('pbs_tv_schedule_call_sign')
  );

  $feeds = array();
  try {
    $feeds = $client->getFeeds();
    if ($feeds_config = variable_get('pbs_tv_schedule_feeds_config')) {
      $feeds = array_merge_recursive($feeds, $feeds_config);
    }
  }
  catch (PbsTvScheduleClientException $e) {
    watchdog_exception('pbs_tv_schedule', $e);
  }

  return $feeds;
}

/**
 * Attempt to create a date object from the `date` URL parameter.
 *
 * @return bool|DateTime
 *   A DateTime object is the date is valid, FALSE otherwise.
 */
function _pbs_tv_schedule_filter_get_date() {
  $date = date('Y-m-d');
  if (isset($_GET['date'])) {
    $date = $_GET['date'];
  }
  $date = DateTime::createFromFormat('Y-m-d', $date);
  if ($date === FALSE) {
    $date = new DateTime();
    drupal_set_message(t('Invalid date provided.'), 'warning');
  }
  $date->setTimezone(new DateTimeZone(drupal_get_user_timezone()));
  return $date;
}

/**
 * Autocomplete handler for programs.
 *
 * Titles are not unique, so it is assumed that any processes dealing with the
 * result of this autocomplete will perform a further query to get and filter
 * any necessary related data for a selected program.
 *
 * @param string $string
 *   The string to use for search.
 */
function _pbs_tv_schedule_autocomplete_program($string) {
  $levenshtein = array();
  $matches = array();

  if (strlen($string) > 2) {
    $result = db_select('pbs_tv_schedule_program', 'ptsp')
      ->fields('ptsp', array('title'))
      ->condition('title', '%' . db_like($string) . '%', 'LIKE')
      ->orderBy('title', 'ASC')
      ->execute();
    foreach ($result as $row) {
      $levenshtein[$row->title] = levenshtein($string, $row->title);
    }
    asort($levenshtein, SORT_NUMERIC);
    foreach (array_slice($levenshtein, 0, 10) as $word => $value) {
      $matches[$word] = check_plain($word);
    }
  }
  drupal_json_output($matches);
}

/**
 * Get a list of upcoming episodes for a searched program.
 *
 * @param string $program_title
 *   Full title of the program to find upcoming episodes for.
 * @param PbsTvScheduleClient $client
 *   TVSS client for querying the API.
 * @param string $feed
 *   Feed to find upcoming episodes on.
 *
 * @return array
 *   Minimal listings data for all upcoming episodes.
 */
function pbs_tv_schedule_program_upcoming_episodes($program_title, PbsTvScheduleClient $client, $feed) {
  $listings = array();

  $program_ids = db_select('pbs_tv_schedule_program', 'ptsp')
    ->fields('ptsp', array('program_id'))
    ->condition('title', trim($program_title))
    ->execute()
    ->fetchCol();
  if (empty($program_ids)) {
    return $listings;
  }

  foreach ($program_ids as $program_id) {
    try {
      $response = $client->getProgramInfo($program_id);
      foreach ($response['upcoming_episodes'] as $listing) {
        if ($listing['feed']['short_name'] == $feed) {
          $listing['title'] = $response['title'];
          $listing['description'] = $response['description'];
          $listing['program_id'] = $response['program_id'];
          $listings[] = $listing;
        }
      }
    }
    catch (PbsTvScheduleClientException $e) {
      watchdog_exception('pbs_tv_schedule', $e);
    }
  }

  return $listings;
}

/**
 * Upcoming airings of a show.
 *
 * @param string $request_method
 *   Request method of "ajax" or "nojs" depending on how this function was
 *   called.
 *
 * @return array
 *   Render array for a page OR an array of AJAX commands.
 */
function pbs_tv_schedule_upcoming($request_method) {
  $page = array();

  // The show_id, feed and "after" parameters are required. The "after"
  // parameter contains the date and time (YmdHi) of the show used as a basis
  // for episodes considered to be "upcoming".
  if (isset($_GET['show_id']) && isset($_GET['feed'])
    && isset($_GET['after'])) {
    $show_id = $_GET['show_id'];
    $feed = $_GET['feed'];
    $after = DateTime::createFromFormat('YmdHi', $_GET['after']);
  }
  else {
    drupal_set_message(t('Required parameters missing.'), 'error');
    return $page;
  }

  /* @var PbsTvScheduleClient $client */
  $client = pbs_tv_schedule_get_api_client(
    variable_get('pbs_tv_schedule_api_key'),
    variable_get('pbs_tv_schedule_call_sign')
  );

  try {
    $response = $client->getShowInfo($show_id);
  }
  catch (PbsTvScheduleClientException $e) {
    watchdog_exception('pbs_tv_schedule', $e);
    return $page;
  }

  $list = array(
    '#theme' => 'item_list',
    '#list_type' => 'ul',
    '#title' => t('Upcoming Airings'),
    '#items' => array(),
  );

  foreach ($response['upcoming_shows'] as $show) {

    // The endpoint returns data for all feeds and cannot be filtered.
    if ($show['feed']['short_name'] != $feed) {
      continue;
    }

    $date = DateTime::createFromFormat('YmdHi', $show['day'] . $show['start_time']);
    if ($date > $after) {
      $list['#items'][] = $date->format('D, M. j g:i a');
    }
  }

  if (empty($list['#items'])) {
    $list = array(
      '#type' => 'html_tag',
      '#tag' => 'em',
      '#value' => t('No upcoming airings currently scheduled.'),
    );
  }

  if ($request_method == 'ajax') {
    $commands = array();
    $commands[] = ajax_command_replace(
      "a[data-show-id='" . $show_id . "']",
      drupal_render($list)
    );
    return array(
      '#type' => 'ajax',
      '#commands' => $commands,
    );
  }

  drupal_set_title(t('@show - Upcoming Airings', array(
    '@show' => $response['title'],
  )));

  $page['description'] = array(
    '#type' => 'html_tag',
    '#tag' => 'p',
    '#value' => $response['description'],
  );

  $page['upcoming'] = $list;

  $page['link'] = array(
    '#theme' => 'link',
    '#text' => t('Return to Schedule'),
    '#path' => 'pbs-tv-schedule/schedule',
    '#options' => array(
      'attributes' => array(),
      'html' => FALSE,
    ),
  );

  return $page;
}

/**
 * Display week-based schedule page.
 *
 * @return array
 *   Page render array.
 */
function pbs_tv_schedule_schedule_week() {
  $base_path = drupal_get_path('module', 'pbs_tv_schedule');
  $page = array();
  $page['#attached'] = array(
    'library' => array(array('system', 'ui.dialog')),
    'css' => array($base_path . '/css/pbs_tv_schedule.css'),
    'js' => array($base_path . '/js/pbs_tv_schedule.js'),
  );

  try {
    /* @see pbs_tv_schedule_schedule_week_filter() */
    $form = drupal_get_form('pbs_tv_schedule_schedule_week_filter');
    $feed = $form['channel']['#default_value'];
    $date = DateTime::createFromFormat('Y-m-d', $form['date']['#value']);
    $date_initial = clone $date;

    // Prevent form elements from appearing in URL.
    $form['form_build_id']['#access'] = FALSE;
    $form['form_token']['#access'] = FALSE;
    $form['form_id']['#access'] = FALSE;

    $page['filter_form'] = $form;

    // Adjust $date to beginning of week.
    $day = $date->format('N') - 1;
    $date->sub(new DateInterval('P' . $day . 'D'));
    $schedule_title = t(
      'Week of @date', array('@date' => $date->format('M. j'))
    );
    drupal_set_title($schedule_title);

    /* @var PbsTvScheduleClient $client */
    $client = pbs_tv_schedule_get_api_client(
      variable_get('pbs_tv_schedule_api_key'),
      variable_get('pbs_tv_schedule_call_sign')
    );

    // Prepare intervals for 30-minute window processing.
    $pt30m = new DateInterval('PT30M');
    $p1d = new DateInterval('P1D');

    $rows = array();
    $prefix_cell = NULL;

    for ($i = 1; $i <= 7; $i++) {
      $rows[$i] = array();
      $rows[$i][] = array(
        '#type' => 'html_tag',
        '#tag' => 'div',
        '#value' => '<span class="schedule-row-header-day">'
        . $date->format('D')
        . '</span><span class="schedule-row-header-date">'
        . $date->format('M. j')
        . '</span>',
        '#attributes' => array(
          'class' => array('schedule-cell', 'schedule-row-header'),
        ),
      );

      if (!empty($prefix_cell)) {
        $rows[$i][] = $prefix_cell;
        $prefix_cell = NULL;
      }

      $response = $client->getFullDay($date->format('Ymd'));

      $listings = $response[$feed]['listings'];
      foreach ($listings as $listing) {
        _pbs_tv_schedule_format_listing($listing);

        $render_array = array(
          '#theme' => 'pbs_tv_schedule_schedule_week_item',
          '#show_id' => $listing['show_id'],
          '#title' => $listing['title'],
          '#subtitle' => $listing['subtitle'],
          '#description' => $listing['description'],
          '#duration' => $listing['minutes'],
          '#closed_captions' => $listing['closed_captions'],
          '#hd' => $listing['hd'],
          '#stereo' => $listing['stereo'],
          '#animated' => $listing['animated'],
          '#flex_basis' => $listing['minutes'],
          '#listing' => $listing,
        );

        // Prepare extra cell for the next row if a program goes over midnight.
        if ($listing['start_time'] + $listing['minutes'] > 2360) {
          $prefix_cell = $render_array;
          $render_array['#flex_basis'] = 2360 - $listing['start_time'];
          $prefix_cell['#flex_basis'] = $listing['start_time'] + $listing['minutes'] - 2360;
        }

        $rows[$i][] = $render_array;
      }

      $date->add($p1d);
    }

    // Create headers.
    $headers = array(t('Day'));
    $date->setTime(0, 0, 0, 0);
    for ($i = 0; $i < 48; $i++) {
      $headers[] = $date->format('g:i a');
      $date->add($pt30m);
    }

    // Create links for previous and next week.
    $date_initial->sub(new DateInterval('P7D'));
    $link_previous = array(
      '#theme' => 'link',
      '#text' => '',
      '#path' => 'pbs-tv-schedule/schedule/week',
      '#options' => array(
        'attributes' => array(
          'title' => t('Previous week'),
        ),
        'query' => array(
          'date' => $date_initial->format('Y-m-d'),
          'channel' => $feed,
        ),
        'html' => FALSE,
      ),
    );

    $date_initial->add(new DateInterval('P14D'));
    $link_next = array(
      '#theme' => 'link',
      '#text' => '',
      '#path' => 'pbs-tv-schedule/schedule/week',
      '#options' => array(
        'attributes' => array(
          'title' => t('Next week'),
        ),
        'query' => array(
          'date' => $date_initial->format('Y-m-d'),
          'channel' => $feed,
        ),
        'html' => FALSE,
      ),
    );
  }
  catch (Exception $e) {
    watchdog_exception('pbs_tv_schedule', $e);
    return $page;
  }

  $page['schedule'] = array(
    '#theme' => 'pbs_tv_schedule_schedule_week',
    '#title' => $schedule_title,
    '#link_previous' => $link_previous,
    '#link_next' => $link_next,
    '#headers' => $headers,
    '#rows' => $rows,
  );

  return $page;
}

/**
 * Filter for the week-based schedule page.
 *
 * @return array
 *   Form render array.
 *
 * @see pbs_tv_schedule_schedule_date()
 */
function pbs_tv_schedule_schedule_week_filter($form, &$form_state) {
  $form['#method'] = 'get';
  $form['#token'] = FALSE;

  if ($date = _pbs_tv_schedule_filter_get_date()) {
    $form['date'] = array(
      '#type' => 'hidden',
      '#value' => $date->format('Y-m-d'),
    );
  }

  /* @var PbsTvScheduleClient $client */
  $client = pbs_tv_schedule_get_api_client(
    variable_get('pbs_tv_schedule_api_key'),
    variable_get('pbs_tv_schedule_call_sign')
  );
  $form_state['storage']['client'] = $client;

  $form['channel'] = _pbs_tv_schedule_channel_filter();

  $form['actions']['submit'] = array(
    '#type' => 'submit',
    '#name' => 'view',
    '#value' => t('View'),
  );

  $form['actions']['reset'] = array(
    '#type' => 'submit',
    '#name' => 'reset',
    '#value' => t('Reset'),
  );

  return $form;
}

/**
 * Format data for a listing item from the API.
 *
 * @param array $listing
 *   A raw API listing response.
 */
function _pbs_tv_schedule_format_listing(array &$listing) {
  $title = $listing['title'];
  if (empty($title)) {
    $listing['title'] = t('Untitled');
  }

  $listing['subtitle'] = NULL;
  if (isset($listing['episode_title'])) {
    $listing['subtitle'] = $listing['episode_title'];
  }

  $listing['parent_description'] = $listing['description'];
  if (isset($listing['episode_description'])) {
    $listing['description'] = $listing['episode_description'];
  }

  if (!isset($listing['show_id'])) {
    $listing['show_id'] = PBS_TV_SCHEDULE_SHOW_ID_NONE;
  }

  $listing['minutes'] = (int) $listing['minutes'];
  $listing['closed_captions'] = (bool) $listing['closed_captions'];
  $listing['hd'] = (bool) $listing['hd'];
  $listing['stereo'] = (bool) $listing['stereo'];
  $listing['animated'] = (bool) $listing['animated'];

  drupal_alter('pbs_tv_schedule_listing', $listing);
}

/**
 * Implements hook_cron().
 */
function pbs_tv_schedule_cron() {
  // Update local cache of TVSS program data.
  $last_updated = variable_get('pbs_tv_schedule_programs_cron_last', 0);
  if (!$last_updated || $last_updated + 86400 < time()) {
    if (_pbs_tv_schedule_programs_update()) {
      variable_set('pbs_tv_schedule_programs_cron_last', time());
    }
  }
}

/**
 * Update local cache of TVSS program data.
 *
 * @return bool
 *   FALSE on error or empty result set. TRUE otherwise.
 */
function _pbs_tv_schedule_programs_update() {
  /* @var PbsTvScheduleClient $client */
  $client = pbs_tv_schedule_get_api_client(
    variable_get('pbs_tv_schedule_api_key'),
    variable_get('pbs_tv_schedule_call_sign')
  );
  try {
    $programs = $client->getPrograms();
    if (!empty($programs)) {
      db_truncate('pbs_tv_schedule_program')->execute();
      $query = db_insert('pbs_tv_schedule_program')
        ->fields(array_keys($programs[0]));
      foreach ($programs as $program) {
        $query->values($program);
      }
      $query->execute();
    }
    else {
      return FALSE;
    }
  }
  catch (Exception $e) {
    watchdog_exception('pbs_tv_schedule', $e);
    return FALSE;
  }
  return TRUE;
}