<?php
/**
 * @file
 *   Multilingual poll - Aggregates poll results for all translations
 * 
 * Most code ripped off poll module and adapted for multilingual results
 */

/**
 * Implementation of hook_form_alter()
 * 
 * Rewrite the cancel vote form with the nid for the translation with the actual vote.
 */
function i18npoll_form_alter(&$form, $form_state, $form_id) {
  if ($form_id == 'poll_cancel_form') {
    if (!empty($form['#nid']) && empty($form['#i18ntnid'])) {
      // Replace nid with the original node the user voted
      $node = node_load($form['#nid']);
      if (!empty($node->tnid) && ($vote = i18npoll_get_vote($node->tnid))) {
        $form['#i18ntnid'] = $node->tnid;
        $form['#nid'] = $vote->nid;
      }
    }
  }
}

/**
 * Implementation of hook_nodeapi()
 * 
 * Replaces poll results with aggregated translations.
 * 
 * We don't add all language results on loading to avoid the data being trashed
 * when editing and saving nodes again
 */
function i18npoll_nodeapi(&$node, $op, $teaser = NULL, $page = NULL) {
  global $user;

  if ($node->type == 'poll' && !empty($node->tnid)) {
    // Replace results for node view
    if ($op == 'view' && (empty($node->allowvotes) || !empty($node->show_results))) {  
      $node->content['body'] = array(
        '#value' => i18npoll_view_results($node, $teaser, $page, FALSE),
      );
    }
    // Check again whether or not this user is allowed to vote.
    // User may have voted for any of the translations
    if ($op == 'load' && $node->allowvotes) {
      $result = i18npoll_get_vote($node->tnid);
      if (isset($result->chorder)) {
        $node->vote = $result->chorder;
        $node->allowvotes = FALSE;
      }
    }
  }
  return $node;  
}

/**
 * Implementation of hook_block().
 *
 * Generates a block containing the latest poll with aggregated results.
 */
function i18npoll_block($op = 'list', $delta = 0) {
  if (user_access('access content')) {
    if ($op == 'list') {
      $blocks[0]['info'] = t('Most recent poll (Aggregated translations)');
      return $blocks;
    }
    else if ($op == 'view') {
      // Retrieve the latest poll.
      $sql = db_rewrite_sql("SELECT MAX(n.created) FROM {node} n INNER JOIN {poll} p ON p.nid = n.nid WHERE n.status = 1 AND p.active = 1");
      $timestamp = db_result(db_query($sql));
      if ($timestamp) {
        $poll = node_load(array('type' => 'poll', 'created' => $timestamp, 'status' => 1));

        if ($poll->nid) {
          $poll = i18npoll_view($poll, TRUE, FALSE, TRUE);
        }
      }
      $block['subject'] = t('Poll');
      $block['content'] = drupal_render($poll->content);
      return $block;
    }
  }
}

/**
 * Implementation of hook_view().
 *
 * @param $block
 *   An extra parameter that adapts the hook to display a block-ready
 *   rendering of the poll.
 */
function i18npoll_view($node, $teaser = FALSE, $page = FALSE, $block = FALSE) {
  global $user;
  $output = '';

  // Special display for side-block
  if ($block) {
    // No 'read more' link
    $node->readmore = FALSE;

    $links = module_invoke_all('link', 'node', $node, 1);
    $links[] = array('title' => t('Older polls'), 'href' => 'poll', 'attributes' => array('title' => t('View the list of polls on this site.')));
    if ($node->allowvotes && $block) {
      $links[] = array('title' => t('Results'), 'href' => 'node/'. $node->nid .'/results', 'attributes' => array('title' => t('View the current poll results.')));
    }

    $node->links = $links;
  }

  if (!empty($node->allowvotes) && ($block || empty($node->show_results))) {
    $node->content['body'] = array(
      '#value' => drupal_get_form('poll_view_voting', $node, $block),
    );
  }
  else {
    $node->content['body'] = array(
      '#value' => i18npoll_view_results($node, $teaser, $page, $block),
    );
  }
  return $node;
}

/**
 * Generates a graphical representation of the results of a poll.
 */
function i18npoll_view_results(&$node, $teaser, $page, $block) {
  // Load the appropriate choices into the $poll object.
  $result = db_query("SELECT c.chorder, SUM(c.chvotes) AS votes FROM {poll_choices} c INNER JOIN {node} n ON c.nid = n.nid WHERE n.tnid = %d GROUP BY c.chorder", $node->tnid);
  while ($choice = db_fetch_object($result)) {
    // If this option not set for the source node, do not show
    if (isset($node->choice[$choice->chorder])) {
      $node->choice[$choice->chorder]['chvotes'] = $choice->votes;
    }
  }
  return poll_view_results($node, $teaser, $page, $block);
}

/**
 * Get user vote for this node or its translations
 * 
 * Returns object with nid, chorder. Has static caching as this will typically be called twice
 */
function i18npoll_get_vote($tnid) {
  global $user;
  static $vote = array();
  if (!array_key_exists($tnid, $vote)) {
    if ($user->uid) {
      $vote[$tnid] = db_fetch_object(db_query('SELECT v.nid, v.chorder FROM {poll_votes} v INNER JOIN {node} n ON n.nid = v.nid WHERE n.tnid = %d AND v.uid = %d', $tnid, $user->uid));
    }
    else {
      $vote[$tnid] = db_fetch_object(db_query("SELECT v.chorder FROM {poll_votes} v INNER JOIN {node} n ON n.nid = v.nid WHERE n.tnid = %d AND v.hostname = '%s'", $tnid, ip_address()));
    }
  }
  return $vote[$tnid];
}