<?php
/**
 * @file
 * Simplenews Scheduler module allows a schedule to be set
 * for sending (and resending) a Simplenews item.
 */

/**
 * NEWSLETTER SEND COMMAND
 */
define('SIMPLENEWS_COMMAND_SEND_SCHEDULE', 3);
define('SIMPLENEWS_COMMAND_SEND_NONE', 4);

/**
 * Implementation of hook_perm().
 */
function simplenews_scheduler_perm() {
  return array('overview scheduled newsletters', 'send scheduled newsletters');
}

/**
 * Implementation of hook_menu().
 */
function simplenews_scheduler_menu() {
  $items = array();
  $items["node/%node/editions"] = array(
    'title' => 'Newsletter Editions',
    'type' => MENU_LOCAL_TASK,
    'weight' => 2,
    'page callback' => 'simplenews_scheduler_node_page',
    'page arguments' => array(1),
    'access callback' => '_simplenews_scheduler_tab_permission',
    'access arguments' => array(1),
  );
  return $items;
}

/**
 * Implementation of hook_form_alter().
 */
function simplenews_scheduler_form_alter(&$form, &$form_state, $form_id) {
  global $user;
  // if this is an edition, then we should be fiddling with it, only the parent.


  // Add schedule settings to the newsletter edit form.
  if (isset($form['simplenews']) && user_access('send scheduled newsletters') && !isset($node->simplenews_scheduler_edition)) {
    drupal_add_js(drupal_get_path('module', 'simplenews_scheduler') . '/simplenews_scheduler.js', 'module', 'header', FALSE, FALSE, TRUE);

    // Set the default values.
    $form['#submit'][] = "simplenews_scheduler_submit";

    $scheduler = array();
    $result = db_query("SELECT * FROM {simplenews_scheduler} WHERE nid = %d", arg(1));
    $row = db_fetch_array($result);
    if ($row) {
      $scheduler = $row;
    }
    else {
      $scheduler['activated'] = 0;
    }

    $form['simplenews']['send']['#options'][SIMPLENEWS_COMMAND_SEND_SCHEDULE] = t('Send newsletter according to schedule');
    $form['simplenews']['send']['#default_value'] = ($scheduler['activated'] == 1) ? SIMPLENEWS_COMMAND_SEND_SCHEDULE : variable_get('simplenews_send', SIMPLENEWS_COMMAND_SEND_NONE);
    $form['simplenews']['send']['#options'][SIMPLENEWS_COMMAND_SEND_NONE] = t("Don't send now or stop sending");
    $form['simplenews']['scheduler'] = array(
      '#type' => 'fieldset',
      '#title' => t('Schedule details'),
      '#attributes' => array('class' => 'schedule_info'),
      '#collapsible' => FALSE,
      '#collapsed' => FALSE,
      '#tree' => TRUE,
    );
    // Display settings only if this is not an edition.
    if (!isset($form['#node']->simplenews_scheduler_edition)) {
      $form['simplenews']['scheduler']['send_interval'] = array(
        '#type' => 'select',
        '#title' => t('Send once per'),
        '#options' => array(
          'hour' => t('Hour'),
          'day' => t('Day'),
          'week' => t('Week'),
          'month' => t('Month'),
        ),
        '#description' => t('Interval to send at'),
        '#default_value'=> isset($scheduler['send_interval']) ? $scheduler['send_interval'] : 'week',
      );

      // If there is no default value, use the current time for start.
      $date_start = isset($scheduler['start_date']) ? $scheduler['start_date'] : time();
      // and Mon, 30 Dec 2013 23:59:59 GMT for stop, that should be enough.
      $date_stop = isset($scheduler['stop_date']) ? $scheduler['stop_date'] : 1388447999;
      $form_date = false;
      if (isset($form['#node'])) {
        // Convert dates to valid date objects.
        if ($form['#node']->build_mode == 1) {
          $date_start = date_make_date($date_start, NULL, DATE_DATETIME);
          $date_stop = date_make_date($date_stop, NULL, DATE_DATETIME);
          $form_date = true;
        }
      }

      if (! $form_date) {
        $date_start = date_make_date($date_start, date_default_timezone_name(), DATE_UNIX);
        $date_stop = date_make_date($date_stop, date_default_timezone_name(), DATE_UNIX);
      }

      // Translate formatted date results.
      $date_str_start = date_format_date($date_start, 'custom', 'Y-m-d H:i');
      $date_str_stop = date_format_date($date_stop, 'custom', 'Y-m-d H:i');
      $form['simplenews']['scheduler']['start_date'] = array(
        '#type' => 'date_select', '#title' => t('Start sending on'),
        '#default_value' => $date_str_start,
        '#date_type' => DATE_DATETIME,
        '#date_format' => 'm-d-Y - H:i',
        '#date_timezone' => date_default_timezone_name(),
        '#date_label_position' => 'none',
        '#date_increment' => 1,
        '#date_year_range' => '0:+3',
        '#required' => TRUE,
        '#description' => t('Intervals work by creating a new node at the
           desired time and marking this to be sent, ensure
           you have your <a href="@site">site timezones</a>
           configured and <a href="@user">user timezone</a>
           configured.', array(
             '@site' => url('admin/settings/date-time'),
             '@user' => url('user/' . $user->uid . '/edit'),
           )),
         );
      $form['simplenews']['scheduler']['stop_type'] = array(
        '#type' => 'radios',
        '#title' => t('Stop sending'),
        '#default_value' => isset($scheduler['stop_type']) ? $scheduler['stop_type'] : 0,
        '#options' => array(
          t('Never'),
          t('On a given date'),
          t('After a maximum number of editions'),
        ),
        '#attributes' => array('class' => 'simplenews-command-stop'),
      );
      $form['simplenews']['scheduler']['stop_date'] = array(
        '#type' => 'date_select',
        '#default_value' => $date_str_stop,
        '#date_type' => DATE_DATETIME,
        '#date_format' => 'm-d-Y - H:i',
        '#date_timezone' => date_default_timezone_name(),
        '#date_label_position' => 'none',
        '#date_increment' => 1,
        '#date_year_range' => '2010:+3',
        '#required' => TRUE,
      );
      $form['simplenews']['scheduler']['stop_edition'] = array(
        '#type' => 'textfield',
        '#default_value' => isset($scheduler['stop_edition']) ? $scheduler['stop_edition'] : 0,
        '#size' => 5,
        '#maxlength' => 5,
        '#required' => TRUE,
        '#description' => t('The maximum number of editions which should be sent.'),
      );
      $form['simplenews']['scheduler']['php_eval'] = array(
        '#type' => 'textarea',
        '#title' => t('Additionally only create newsletter edition if the following code returns true'),
        '#default_value' => isset($scheduler['php_eval']) ? $scheduler['php_eval'] : '',
        '#required' => FALSE,
        '#description' => t('Additionally evaluate the following PHP code and only issue the newsletter edition if it returns true. Do not include &lt;?php ?&gt; tags.'),
      );
      $form['simplenews']['scheduler']['title'] = array(
        '#type' => 'textfield',
        '#title' => t('Title pattern for new edition nodes'),
        '#description' => t('New edition nodes will have their title set to the above string, with tokens replaced.'),
        '#required' => TRUE,
        '#default_value' => isset($scheduler['title']) ? $scheduler['title'] : '[title]',
      );
      $form['simplenews']['scheduler']['token_help'] = array(
        '#title' => t('Replacement patterns'),
        '#type' => 'fieldset',
        '#collapsible' => TRUE,
        '#collapsed' => TRUE,
      );
      $form['simplenews']['scheduler']['token_help']['help'] = array(
        '#value' => theme('token_help', array('node', 'global')),
      );
      $form['simplenews']['scheduler']['activated'] = array(
        '#type' => 'hidden',
        '#value' => $scheduler['activated'],
      );
    }
    else {
      // This is a newsletter edition.
      $title .= t('This node is part of a scheduled newsletter configuration. View the original newsletter <a href="@parent">here</a>.', array('@parent' => url('node/' . $form['#node']->simplenews_scheduler_edition['pid'])));
      $form['simplenews']['none']['#title'] = $title;
      // If the node has attachments
      if (count($form['attachments']['wrapper']['files']) && user_access('upload files')) {
        // Disable all attachment form elements and the delete button to avoid the deletion of the parent's attachments.
        $form['attachments']['#description'] = t('Attachments cannot be changed, this is a newsletter edition created by Simplenews Scheduler.');
        $form['attachments']['wrapper']['new']['upload']['#disabled'] = TRUE;
        $form['attachments']['wrapper']['new']['attach']['#disabled'] = TRUE;
        // Disable every file element.
        foreach ($form['attachments']['wrapper']['files'] as $key => $file) {
          if (is_numeric($key)) {
            $form['attachments']['wrapper']['files'][$key]['description']['#disabled'] = TRUE;
            $form['attachments']['wrapper']['files'][$key]['remove']['#disabled'] = TRUE;
            $form['attachments']['wrapper']['files'][$key]['list']['#disabled'] = TRUE;
            $form['attachments']['wrapper']['files'][$key]['weight']['#disabled'] = TRUE;
            $form['buttons']['delete']['#disabled'] = TRUE;
          }
        }
      }
    }
  }
}

function simplenews_scheduler_submit($form, &$form_state) {

  $nid = $form_state['values']['nid'];
  $node = node_load($nid);

  // Get Scheduler values from Simplenews.
  $send = $form_state['values']['simplenews']['send'];
  // Change activation status if necessary.
  switch ($send) {
    case 0 :
    case 1 :
      $activated = 0;
      break;
    case 3 :
      $activated = 1;
      break;
  }

  $start_date = $form_state['values']['simplenews']['scheduler']['start_date'];
  $stop_date = $form_state['values']['simplenews']['scheduler']['stop_date'];
  // Convert the user time back to GMT time and use that as our record.
  $start_date = date_convert($start_date, DATE_DATETIME, DATE_UNIX, date_default_timezone_name());
  $stop_date = date_convert($stop_date, DATE_DATETIME, DATE_UNIX, date_default_timezone_name());

  $record = array(
    'nid'           => $nid,
    'activated'     => $activated,
    'send_interval' => $form_state['values']['simplenews']['scheduler']['send_interval'],
    'start_date'    => $start_date,
    'stop_type'     => $form_state['values']['simplenews']['scheduler']['stop_type'], // number of edition
    'stop_date'     => $stop_date,
    'stop_edition'  => $form_state['values']['simplenews']['scheduler']['stop_edition'],
    'php_eval'      => $form_state['values']['simplenews']['scheduler']['php_eval'],
    'title'         => $form_state['values']['simplenews']['scheduler']['title'],
  );

  db_query("DELETE FROM {simplenews_scheduler} WHERE nid = %d", $nid);
  $result = drupal_write_record('simplenews_scheduler', $record);

  if (! $result) {
    drupal_set_message(t('Saving or updating schedule settings for <em>@title</em> has been unsuccessful.', array(
      '@title' => $node->title
    )), 'error');
  }
  else {
    drupal_set_message(t('Newsletter Schedule preferences saved'));
  }
}

/**
 * Implementation of hook_nodeapi().
 */
function simplenews_scheduler_nodeapi(&$node, $op) {
  if (in_array($node->type, variable_get('simplenews_content_types', array('simplenews')))) {
    switch ($op) {
      case 'load':
        if (isset($node->nid)) {
          $result = db_query("SELECT * FROM {simplenews_scheduler} WHERE nid = %d", $node->nid);
          $row = db_fetch_array($result);
          if ($row) {
            $node->simplenews_scheduler = $row;
          }
          else {
            // Maybe this was an edition that has been sent?
            $result = db_query("SELECT * FROM {simplenews_scheduler_editions} WHERE eid = %d", $node->nid);
            $row = db_fetch_array($result);
            if ($row) {
              $node->simplenews_scheduler_edition = $row;
            }
          }
        }
        break;
     case 'delete':
       // erase the record from the scheduler table so it does not try to send
       db_query("DELETE FROM {simplenews_scheduler} WHERE nid = %d", $node->nid);
     break;
     case 'view':
      // leaving this out until we figure out a nicer UI for showing this.
      // this should be letting you know that you are viewing a generated newsletter, not the original
     /*  if(isset($node->simplenews_scheduler_edition)) {
         drupal_set_message(t('You have been redirected to the original newsletter'));
         drupal_goto('node/'.$node->simplenews_scheduler_edition['pid'].'/simplenews');
       }
      */
     break;
    }
  }
}

/**
 * Implementation of hook_cron().
 *
 * Essentially we are just checking against a status table
 * and recreating nodes to be sent.
 *
 */
function simplenews_scheduler_cron() {

  module_load_include('inc', 'simplenews', 'includes/simplenews.mail');
  // Set the default intervals for scheduling.
  $intervals['hour'] = 3600;
  $intervals['day'] = 86400;
  $intervals['week'] = $intervals['day'] * 7;
  $intervals['month'] = $intervals['day'] * date_days_in_month(date('Y'), date('m'));
  foreach ($intervals as $interval => $seconds) {
    // Check daily items that need to be sent.
    $now_time = gmmktime();
    $result = db_query("SELECT * FROM {simplenews_scheduler} WHERE activated = 1 AND %d - last_run > %d AND send_interval = '%s' AND start_date <= %d AND %d < stop_date", $now_time, $seconds, $interval, $now_time, $now_time);
    while ($row = db_fetch_array($result)) {
      // does this newsletter have something to evaluate to check running condition?
      if (strlen($row['php_eval'])) {
        $eval_result = eval($row['php_eval']);
        if (! $eval_result) {
          break;
        }
      }

      $pid = $row["nid"];
      // If returns with null don't do anything.
      $first_run = intval($row['start_date']);
      // Because the scheduler runs according to last_run timestamp and the cron
      // does not run exactly at the scheduled timestamp, this correction fixes
      // this run's timestamp ($now_time) to the right time by adding a correct interval.
      $this_run = $first_run + floor(($now_time - $first_run) / $seconds) * $seconds;
      // Create a new edition.
      $eid = _simplenews_scheduler_new_edition($row["nid"]);
      if (isset($eid)) {
        db_query("UPDATE {simplenews_scheduler} SET last_run = %d WHERE nid = %d", $this_run, $pid);
        $node = node_load($eid);
        // Send the newsletter edition to each subscriber of the parent newsletter
        // get the tid of this newsletter and generate a list of accounts to send this new newsletter to, based on the parent newsletter.
        $tid = db_result(db_query("SELECT tid from {simplenews_newsletters} WHERE nid = %d", $node->nid));
        $accounts = simplenews_scheduler_get_newsletter_accounts($tid);
        simplenews_send_node($node, $accounts);
      }
    }
  }
}

// @todo: might be a better already existing function for this
function simplenews_scheduler_get_newsletter_accounts($newsletter_tid) {

  // taken from the newsletter subscription list
   $query = '
    SELECT DISTINCT ss.snid, ss.*, u.name
    FROM {simplenews_subscriptions} ss
    LEFT JOIN {users} u
      ON ss.uid = u.uid
    INNER JOIN {simplenews_snid_tid} s
      ON ss.snid = s.snid
    AND s.tid = %d AND s.status = 1';

   $result = db_query($query, $newsletter_tid);

  // build the accounts array
  /* @param array $accounts  account objects to send the newsletter to.
     *   account = object (
     *     snid     = subscription id, or 0 if no subscription record exists.
     *     tids     = array(tid) array of newsletter tid's.
     *     uid      = user id, or 0 if subscriber is anonymous user.
     *     mail     = user email address.
     *     name     = <empty>. Added for compatibility with user account object.
     *     language = language object. User-preferred or default language.
     *
     */
  $accounts = array();
  while ($account = db_fetch_object($result)) {
    $account->tids = array(
      $newsletter_tid
    );
    $accounts[] = $account;
  }

   return $accounts;
}
/**
 * Menu callback to provide an overview page with the scheduled newsletters.
 */
function simplenews_scheduler_node_page($node) {
  drupal_set_title(t('Scheduled newsletter editions'));
  $nid = _simplenews_scheduler_get_pid($node);
  // This is the original newsletter.
  if ($nid == $node->nid) {
    $output .= '<p>' . t('This is the original newsletter of which all editions are based on.') . '</p>';
  }
  // This is a newsletter edition.
  else {
    $output .= '<p>' . t('This node is part of a scheduled newsletter configuration. View the original newsletter <a href="@parent">here</a>.', array('@parent' => url('node/' . $nid))) . '</p>';
  }
  // Load the corresponding editions from the database to further process.
  $result = pager_query("SELECT * FROM {simplenews_scheduler_editions} sse LEFT JOIN {node} n ON n.nid = sse.pid WHERE sse.pid = %d", 20, 0, NULL, $nid);
  while ($row = db_fetch_object($result)) {
    $node = node_load($row->eid);
    $rows[] = array(format_date($row->date_issued, 'custom', 'Y-m-d H:i'), l($node->title, 'node/' . $row->eid));
  }
  // Display a table with all editions.
  if (! empty($rows)) {
    $output .= theme('table', array(t('Date sent'), t('Node')), $rows, array('class' => 'schedule_history'));
    $output .= theme('pager', 20);
  }
  else {
    $output .= '<p>' . t('No scheduled newsletters have been sent.') . '</p>';
  }
  return $output;
}

/**
 * Check whether to display the Scheduled Newsletter tab.
 */
function _simplenews_scheduler_tab_permission($node) {
  if (in_array($node->type, variable_get('simplenews_content_types', array('simplenews'))) && user_access('overview scheduled newsletters')) {
    $pid = _simplenews_scheduler_get_pid($node);
    // Only display the tab if there is a parent template newsletter or if this
    // is itself a template newsletter.
    return !empty($pid);
  }
  else {
    return FALSE;
  }
}

/**
 * Use the Drupal API for finding the Full HTML input format, this is what the subsequent newsletter editions
 * need to be set to.
 */
function _simplenews_scheduler_get_full_html_format() {
  $formats = filter_formats();

  foreach ($formats as $index => $format) {
    if (stristr($format->name, 'Full HTML')) {
      return $index;
    }
  }

  return false;
}

/**
 * Create a new newsletter edition.
 */
function _simplenews_scheduler_new_edition($nid) {
  $node = node_load($nid);

  if (module_exists('upload')) {
    $files = upload_load($node);
  }

  // Switch to the anonymous user to render node content.
  // This prevents things like Views admin links from showing in edition node body.
  global $user;
  if ($user->uid) {
    // Store the current user and session so we can restore them.
    $original_user = $user;
    $old_state = session_save_session();

    // Disable session saving and load the anonymous user.
    session_save_session(FALSE);
    $user = user_load(0);
  }

  // Render node content.
  $node = node_build_content($node, FALSE, FALSE);
  $content = drupal_render($node->content);
  // Keep the teaser in sync with the rendered node content.
  $node->teaser = node_teaser($node->body, isset($node->format) ? $node->format : NULL);

  // Restore the original user if necessary.
  if (isset($original_user)) {
    $user = $original_user;
    session_save_session($old_state);
  }

  // Store taxonomy terms to save later to the node.
  $terms = $node->taxonomy;

  // Output format for all newly created items should just be Full HTML, incase of Views output etc.
  if ($format_id = _simplenews_scheduler_get_full_html_format()) {
    $node->format = $format_id;
  }

  // Trigger it for sending.
  $node->simplenews['send'] = 1;

  // Check upon if sending should stop with a given edition number.
  $result = db_fetch_array(db_query("SELECT stop_type, stop_edition FROM {simplenews_scheduler} WHERE nid = %d", $nid));
  $stop = $result['stop_type'];
  $stop_edition = $result['stop_edition'];
  // Don't create new edition if the edition number exceeds the given maximum value.
  if (($stop == 2 && $serial <= $stop_edition) || $stop != 2) {
    // Mark as new with removeing node ID and creation date.
    unset($node->nid, $node->created, $node->path);
    // Run the title through token replacement.
    $title_pattern = $node->simplenews_scheduler['title'];
    $node->title = token_replace($title_pattern, 'node', $node);
    // Mark as new edition.
    $node->is_edition = TRUE;
    // Now save it as a new node.
    node_save($node);
    // Save taxonomy terms.
    taxonomy_node_save($node, $terms);
    watchdog('simplenews_sched', 'Saved new node ready to be sent. Node ID: !nid', array(
      '!nid' => $node->nid
    ));
    // If the node has attachments.
    if (isset($files) && count($files)) {
      // Simply copy the corresponding records in files and upload tables without duplicate the file.
      foreach ($files as $file) {
        db_query_range("INSERT INTO {files} (uid, filename, filepath, filemime, filesize, status, timestamp) (SELECT uid, filename, filepath, filemime, filesize, status, timestamp FROM {files} WHERE filename = '%s')", $file->filename, 0, 1);
        db_query("INSERT INTO {upload} (fid, nid, vid, list, description, weight) VALUES ((SELECT MAX(fid) AS fid FROM files WHERE filename = '%s'), %d, %d, %d, '%s', %d)", $file->filename, $node->nid, $node->vid, $file->list, $file->description, $file->weight);
      }
    }
    // Prepare the correct status for Simplenews to pickup.
    db_query("UPDATE {simplenews_newsletters} SET s_status=1 WHERE nid=%d", $node->nid);

    // ensure this edition has the same simplenews_newsletter settings as the parent
    // also ensures the 'tid' is set, so we use the same newsletter settings as the parent
    if ($newsletter = db_fetch_array(db_query("SELECT * from {simplenews_newsletters} WHERE nid = %d", $nid))) {
      db_query("UPDATE {simplenews_newsletters} SET s_status = 1, tid = %d, s_format = '%s', priority = %d, receipt = %d WHERE nid=%d", $newsletter['tid'], $newsletter['s_format'], $newsletter['priority'], $newsletter['receipt'], $node->nid);
    }

    // Record the new edition.
    $now_time = gmmktime();
    db_query("INSERT INTO {simplenews_scheduler_editions} (eid, pid, date_issued) VALUES (%d, %d, %d)", $node->nid, $nid, $now_time);

    return $node->nid;
  }
}

/**
 * Helper function to get the identifier of newsletter.
 *
 * @param $node
 *  The node object for the newsletter.
 *
 * @return
 *  If the node is a newsletter edition, the node id of its parent template
 *  newsletter; if the node is a template newsletter, its own node id; and
 *  FALSE if the node is not part of a scheduled newsletter set.
 */
function _simplenews_scheduler_get_pid($node) {
  $nid = FALSE;

  // First assume this is a newsletter edition,
  if (isset($node->simplenews_scheduler_edition)) {
    $nid = $node->simplenews_scheduler_edition['pid'];
  }
  // or this itself is the parent newsletter.
  elseif (isset($node->simplenews_scheduler)) {
    $nid = $node->nid;
  }

  return $nid;
}

