<?php

/**
 * @file
 * Advanced Poll - a sophisticated polling module for voting, elections, and group decision-making.
 */

define('ADVPOLL_MAX_CHOICES', 0);
define('ADVPOLL_RUNTIME', 0);
define('ADVPOLL_ELECTORAL_LIST', 0);
define('ADVPOLL_SHOW_VOTES', 1);
define('ADVPOLL_WRITEINS', 0);
define('ADVPOLL_SHOW_WRITEINS', 0);
define('ADVPOLL_INITIAL_CHOICES', 5);
define('ADVPOLL_USE_QUESTION', 0);
define('ADVPOLL_CHOICE_MAX_LENGTH', 2048);
define('ADVPOLL_MAX_POINTS', 2);
define('ADVPOLL_LOW_RATING_LABEL', 'Worst');
define('ADVPOLL_HIGH_RATING_LABEL', 'Best');
define('ADVPOLL_OVERALL_RATING_LABEL', 'Overall');
define('ADVPOLL_DISPLAY_OVERALL_RATING', 1);
define('ADVPOLL_DISPLAY_AVG_RESULTS', 1);
// Options: always, aftervote, or afterclose.
define('ADVPOLL_VIEW_RESULTS', 'aftervote');

/**
 * Implementation of hook_help().
 */
function advpoll_help($path, $arg) {
  switch ($path) {
    case 'admin/modules#description':
      return t('A sophisticated polling module for voting, elections, and group decision-making.');
      break;
  }
}

/**
 * Implementation of hook_perm().
 */
function advpoll_perm() {
  return array(
    'create polls',
    'edit polls',
    'edit own polls',
    'vote on polls',
    'cancel own vote',
    'administer polls',
    'inspect all votes',
    'show vote results',
    'access electoral list',
    'add write-ins',
  );
}

/**
 * Implementation of hook_access().
 */
function advpoll_access($op, $node, $account) {
  if ($op == 'create') {
    return user_access('create polls', $account);
  }
  if ($op == 'update') {
    if (user_access('edit polls', $account) || ($node->uid == $account->uid && user_access('edit own polls', $account))) {
      return TRUE;
    }
  }
}

/**
 * Implementation of hook_node_info().
 */
function advpoll_node_info() {
  $modes = _advpoll_list_modes();
  $info = array();
  foreach ($modes as $mode) {
    $info['advpoll_'. $mode['name']] = array(
      'name' => t('@name poll', array('@name' => $mode['name_label'])),
      'module' => 'advpoll',
      'description' => $mode['description'],
      'title_label' => t('@name question', array('@name' => $mode['name_label'])),
      'body_label' => t('Description'),
    );
  }
  return $info;
}

/**
 * Implementation of hook_menu().
 */
function advpoll_menu() {
  global $user;

  $modes = _advpoll_list_modes();
  $menu = array();

  $menu['advpoll/cancel/%node'] = array(
    'title' => 'Cancel Vote',
    'page callback' => 'advpoll_cancel',
    'page arguments' => array(2),
    'access arguments' => array('cancel own vote'),
    'type' => MENU_CALLBACK,
    'file' => 'advpoll.admin.inc',
  );

  $menu['advpoll/js_vote'] = array(
    'title' => 'Vote via JavaScript',
    'page callback' => 'advpoll_js_vote',
    'access arguments' => array('vote on polls'), // TODO: be more specific here.
    'type' => MENU_CALLBACK,
  );

  $menu['advpoll/js_more_choices'] = array(
    'title' => 'More Choices via JavaScript',
    'page callback' => 'advpoll_js_more_choices',
    'access arguments' => array('access content'), // TODO: be more specific here.
    'type' => MENU_CALLBACK,
  );

  $menu['polls'] = array(
    'title' => 'Advanced Polls',
    'page callback' => 'advpoll_page',
    'access arguments' => array('access content'),
    'type' => MENU_SUGGESTED_ITEM,
    'file' => 'advpoll.pages.inc',
  );

  $menu['node/%node/results'] = array(
    'title' => 'Results',
    'page callback' => 'advpoll_results_page',
    'page arguments' => array(1),
    'access callback' => '_advpoll_results_access',
    'access arguments' => array(1),
    'weight' => 3,
    'type' => MENU_LOCAL_TASK,
    'file' => 'advpoll.pages.inc',
  );

  $menu['node/%node/votes'] = array(
    'title' => 'Votes',
    'page callback' => 'advpoll_votes_page',
    'page arguments' => array(1),
    'access callback' => '_advpoll_votes_access',
    'access arguments' => array(1),
    'weight' => 3,
    'type' => MENU_LOCAL_TASK,
    'file' => 'advpoll.pages.inc',
  );

  // Show electoral list tab if using the functionality.
  $menu['node/%node/electoral_list'] = array(
    'title' => 'Electoral list',
    'page callback' => 'advpoll_electoral_list_page',
    'page arguments' => array(1),
    'access callback' => '_advpoll_electoral_list_access',
    'access arguments' => array(1),
    'weight' => 3,
    'type' => MENU_LOCAL_TASK,
    'file' => 'advpoll.pages.inc',
  );

  // Allow voters to be removed.
  $menu['node/%node/remove'] = array(
    'page callback' => 'advpoll_remove_voter',
    'page arguments' => array(1),
    'access arguments' => array('administer polls'),
    'weight' => 3,
    'type' => MENU_CALLBACK,
    'file' => 'advpoll.admin.inc',
  );

  // Allow votes to be cleared.
  $menu['node/%node/votes/clear'] = array(
    'page callback' => 'advpoll_clear_votes_page',
    'page arguments' => array(1),
    'access callback' => '_advpoll_clear_votes_access',
    'access arguments' => array(1),
    'weight' => 3,
    'type' => MENU_LOCAL_TASK,
    'file' => 'advpoll.pages.inc',
  );

  // Show the write-ins tab if there is at least one.
  $menu['node/%node/writeins'] = array(
    'title' => 'Write-ins',
    'page callback' => 'advpoll_writeins_page',
    'page arguments' => array(1),
    'access callback' => '_advpoll_writeins_access',
    'access arguments' => array(1),
    'weight' => 3,
    'type' => MENU_LOCAL_TASK,
    'file' => 'advpoll.pages.inc',
  );

  return $menu;
}

/**
 * Implementation of hook_init().
 */
function advpoll_init() {
  // Use poll.module's stylesheet, no need to duplicate at this point.
  drupal_add_css(drupal_get_path('module', 'poll') .'/poll.css');
  
  // Load the mode include files.
  _advpoll_list_modes();

}

/**
 * Results access callback.
 */
function _advpoll_results_access($node) {
  return strstr($node->type, 'advpoll_') && _advpoll_is_active($node) && $node->votes > 0 && !$node->voted && _advpoll_can_view_results($node);
}

/**
 * Electorial list access callback.
 */
function _advpoll_electoral_list_access($node) {
  return user_access('access electoral list') && strstr($node->type, 'advpoll_') &&  $node->use_list;
}

/**
 * Votes access callback.
 */
function _advpoll_votes_access($node) {
  return strstr($node->type, 'advpoll_') && $node->votes > 0 && ((user_access('inspect all votes') && $node->show_votes) || user_access('administer polls'));
}

/**
 * Clear votes access callback.
 */
function _advpoll_clear_votes_access($node) {
  return strstr($node->type, 'advpoll_') && $node->votes > 0 && user_access('administer polls');
}

/**
 * Writeins access callback.
 */
function _advpoll_writeins_access($node) {
  if (!strstr($node->type, 'advpoll_') || !user_access('administer polls')) {
    return FALSE;
  }

  foreach ($node->choice as $choice) {
    if ($choice['writein']) {
      // Has at least one write-in choice.
      return TRUE;
    }
  }
  return FALSE;
}

/**
 * Implementation of hook_block().
 */
function advpoll_block($op = 'list') {
  switch ($op) {
    case 'list':
      $blocks['latest_poll']['info'] = t('Latest poll');
      return $blocks;
    case 'view':
      $block['subject'] = t('Latest poll');
      $block['content'] = theme('advpoll_block_latest_poll');
      return $block;
  }
}

/**
 * Content of the block, as returned by advpoll_block('view').
 */
function theme_advpoll_block_latest_poll() {
  $node = advpoll_latest_poll();
  $output = '';
  if ($node) {
    $output .= '<h3>'. l($node->title, 'node/'. $node->nid) .'</h3>';
    $output .= drupal_render($node->content);
    if ($node->voted) {
      $output .= '<p>'. l(t('Older polls'), 'polls', array('class' => 'old-polls', 'title' => t('View the list of polls on this site.'))) .'</p>';
    }
  }
  return $output;
}

/**
 * .
 */
function advpoll_latest_poll() {
  $result = db_query('SELECT MAX(n.nid) AS nid FROM {node} n INNER JOIN {advpoll} p ON p.nid = n.nid WHERE n.status = 1 AND p.active = 1');
  $poll = db_fetch_object($result);
  // The nid will be NULL if there are no active polls.
  if ($poll->nid) {
    $node = advpoll_view(node_load($poll->nid), FALSE, FALSE);
  }
  return $node;
}

/**
 * Implementation of hook_form().
 *
 * This hook displays the form necessary to create/edit the poll.
 */
function advpoll_form(&$node, $form_state) {
  $mode = _advpoll_get_mode($node->type);
  $type = node_get_types('type', $node);
  $editing = isset($node->nid);
  $form = array();

  // Only add javascript once, even if _form is called multiple times.
  static $add_js;
  if (!$add_js) {
    // Pass translatable strings
    drupal_add_js(array('advPoll' => array('remove' => t('Remove'), 'addChoice' => t('Add choice'), 'noLimit' => t('No limit'))), 'setting');
    drupal_add_js(drupal_get_path('module', 'advpoll') .'/advpoll-form.js', 'module');
    drupal_add_css(drupal_get_path('module', 'advpoll') .'/advpoll.css', 'module');
    $add_js = TRUE;
  }

  $form['title'] = array(
    '#type' => 'textfield',
    '#maxlength' => 255,
    '#title' => check_plain($type->title_label),
    '#required' => TRUE,
    '#default_value' => $node->title,
  );

  if ($type->has_body) {
    $form['body_field'] = node_body_field($node, $type->body_label, $type->min_word_count);
  }

  if (isset($form_state['values']['choices'])) {
    $choices = $form_state['values']['choices'];
    if ($form_state['values']['more_choices']) {
      $choices *= 2;
    }
  }
  else {
    $choices = max(2, isset($node->choice) && count($node->choice) ? count($node->choice) : ADVPOLL_INITIAL_CHOICES);
  }

  if (variable_get('advpoll_use_question_'. $type->type, ADVPOLL_USE_QUESTION) || (isset($node->question) && $node->question !== '')) {
    $form['question'] = array(
      '#type' => 'textfield',
      '#title' => t('Question'),
      '#default_value' => $node->question,
      '#maxlength' => 255,
    );
  }

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

  // Advanced Poll choices
  $form['choice'] = array(
    '#type' => 'fieldset',
    '#title' => t('Poll choices'),
    '#collapsible' => TRUE,
    '#prefix' => '<div class="poll-form" id="poll-choices">',
    '#suffix' => '</div>',
    '#tree' => TRUE,
    '#weight' => 1,
  );

  if ($editing) {
    $form['choice']['choice_note'] = array(
      '#value' => '<div id="edit-settings-choice-note" class="description">'. t('Note: adding or removing choices after voting has begun is not recommended.') .'</div>',
    );
  }

  $form['choice']['more_choices'] = array(
    '#type' => 'checkbox',
    '#title' => t('Need more choices'),
    '#value' => 0,
    '#parents' => array('more_choices'), // Don't pollute $form['choice']
    '#prefix' => '<div id="more-choices">',
    '#suffix' => '</div>',
    '#description' => t("If the number of choices above isn't enough, click hereto add more choices."),
    '#weight' => 1,
    /*
    '#submit' => array('advpoll_more_choices_submit'), // If no JavaScript.
    '#ahah' => array(
      'path' => 'advpoll/js_more_choices',
      'wrapper' => 'poll-choices',
      'method' => 'replace',
      'effect' => 'fade',
    ),
    */
  );

  // First, loop through any currently existing choices.
  $current_choices = 0;
  $default_choices = variable_get('advpoll_choices_'. $type->type, '');
  if (isset($node->choice)) {
    foreach ($node->choice as $index => $choice) {
      $form['choice'][$index]['label'] = array(
        '#type' => 'textfield',
        '#title' => t('Choice %n', array('%n' => $current_choices + 1)) . ($choice['writein'] ? ' '. t('(write-in)') : ''),
        '#default_value' => $choice['label'],
        '#attributes' => array('class' => 'choices'),
        '#maxlength' => variable_get('advpoll_choice_max_length', ADVPOLL_CHOICE_MAX_LENGTH),
      );
      $current_choices++;
      $next_index = $index + 1;
    }
  }
  elseif ($default_choices != '') {
    $default_choices = explode("\n", $default_choices);
    foreach ($default_choices as $index => $label) {
      $form['choice'][$index]['label'] = array(
        '#type' => 'textfield',
        '#title' => t('Choice %n', array('%n' => $current_choices + 1)),
        '#default_value' => $label,
        '#attributes' => array('class' => 'choices'),
      );
      $current_choices++;
      $next_index = $index + 1;
    }
  }
  else {
    $next_index = 1;
  }

  // Now add on extra choices if we need to.
  if ($current_choices < $choices) {
    for ($index = $next_index; $current_choices < $choices; $index++, $current_choices++) {
      $form['choice'][$index]['label'] = array(
        '#type' => 'textfield',
        '#title' => t('Choice %n', array('%n' => $current_choices + 1)),
        '#attributes' => array('class' => 'choices'),
        '#maxlength' => variable_get('advpoll_choice_max_length', ADVPOLL_CHOICE_MAX_LENGTH),
      );
    }
  }

  $form['settings'] = array(
    '#type' => 'fieldset',
    '#title' => t('Poll settings'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
    '#weight' => 2,
    '#tree' => TRUE,
  );

  $max_choice_list = array();
  for ($i = 0; $i <= $choices; $i++) {
    $max_choice_list[$i] = ($i == 0 ? t('No limit') : $i);
  }
$max_points_list = array();
  for ($i = 2; $i <= 20; $i++) {
    $max_points_list[$i] = $i;
  }
 
  // Hide this option if it is a multirate poll as it is not used.
  $form['settings']['max_choices'] = array(
    '#type' => ($node->type != 'advpoll_multirate') ? 'select' : 'hidden',
    '#title' => t('Maximum choices'),
    '#default_value' => isset($node->max_choices) ? $node->max_choices : variable_get('advpoll_max_choices_'. $type->type, ADVPOLL_MAX_CHOICES),
    '#options' => $max_choice_list,
    '#description' => t('Limits the total number of choices voters may select.')
  );
// Hide this option if it is not a multirate poll as it is not used otherwise
  $form['settings']['max_points'] = array(
    '#type' => ($node->type == 'advpoll_multirate') ? 'select' : 'hidden',
    '#title' => t('Maximum points'),
    '#default_value' => isset($node->max_points) ? $node->max_points : variable_get('advpoll_max_points_' . $type->type, ADVPOLL_MAX_POINTS),
    '#options' => $max_points_list,
    '#description' => t('The maximum number of points a user can give each criteria.')
  );

  if ($node->type == 'advpoll_multirate') {
    $form['settings']['display_avg_results'] = array(
      '#type' => 'checkbox',
      '#title' => t('Display average results'),
      '#description' => t("If checked, the results displayed with be the averages of all the ratings, otherwise the results will be totals of all the ratings."),
      '#default_value' => isset($node->display_avg_results) ? $node->display_avg_results : ADVPOLL_DISPLAY_AVG_RESULTS,
    );

    $form['settings']['display_overall_rating'] = array(
      '#type' => 'checkbox',
      '#title' => t('Display overall rating'),
      '#description' => t("If checked, an extra 'Overall' rating will be shown with the poll results, which is the average of all the criteria.  Users don't give a rating for this, it is automatically calculated from their ratings of the other criteria."),
      '#default_value' => isset($node->display_overall_rating) ? $node->display_overall_rating : ADVPOLL_DISPLAY_OVERALL_RATING,
    );

    $form['settings']['low_rating_label'] = array(
      '#type' => 'textfield',
      '#title' => t('Low rating label'),
      '#description' => t('The label you want for the lowest possible rating for a given criteria. Defaults to %default.', array('%default' => ADVPOLL_LOW_RATING_LABEL)),
      '#maxlength' => 32,
      '#default_value' => isset($node->low_rating_label) ? $node->low_rating_label : ADVPOLL_LOW_RATING_LABEL,
    );

    $form['settings']['high_rating_label'] = array(
      '#type' => 'textfield',
      '#title' => t('High rating label'),
      '#description' => t('The label you want for the highest possible rating for a given criteria. Defaults to %default.', array('%default' => ADVPOLL_HIGH_RATING_LABEL)),
      '#maxlength' => 32,
      '#default_value' => isset($node->high_rating_label) ? $node->high_rating_label : ADVPOLL_HIGH_RATING_LABEL,
    );

    $form['settings']['overall_rating_label'] = array(
      '#type' => 'textfield',
      '#title' => t('Overall rating label'),
      '#description' => t('The label you want for the overall rating. Defaults to %default.', array('%default' => ADVPOLL_OVERALL_RATING_LABEL)),
      '#maxlength' => 32,
      '#default_value' => isset($node->overall_rating_label) ? $node->overall_rating_label : ADVPOLL_OVERALL_RATING_LABEL,
    );
  }
  
  $voting_algorithms = advpoll_algorithms($mode);
  if (count($voting_algorithms) > 1) {
    // Create a select field when the poll supports several algorithms.
    $form['settings']['algorithm'] = array(
      '#type' => 'select',
      '#title' => t('Algorithm'),
      '#options' => $voting_algorithms,
      '#default_value' => isset($node->algorithm) ? $node->algorithm : variable_get('advpoll_algorithm_'. $type->type, key($voting_algorithms)),
      '#description' => t('Voting algorithm to use to calculate the winner.'),
    );
  }
  else {
    // Pass the only algorithm as a value.
    $form['settings']['algorithm'] = array(
      '#type' => 'value',
      '#value' => key($voting_algorithms),
    );
  }

  $form['settings']['close'] = array(
    '#type' => 'checkbox',
    '#title' => t('Close poll'),
    '#description' => t('When a poll is closed users may no longer vote on it.'),
    '#default_value' => isset($node->active) ? !$node->active : 0,
  );

  $default_start_date = '';
  $default_end_date = '';
  $time = format_date(time(), 'custom', 'Y-m-d H:i:s O');
  // Specify default dates if default duration is set and we are creating a node.
  if (variable_get('advpoll_runtime_'. $type->type, FALSE) && !$editing) {
    $default_start_date = $time;
    $default_end_date = format_date(time() + variable_get('advpoll_runtime_'. $type->type, ''), 'custom', 'Y-m-d H:i:s O');
  }

  $form['settings']['start_date'] = array(
    '#type' => 'textfield',
    '#title' => t('Starting date'),
    '#description' => t('The date that the poll opens. Format: %time. Leave blank if you want the poll to open now.', array('%time' => $time)),
    '#size' => 25,
    '#maxlength' => 25,
    // Use !empty() because 0 signifies that no date should be used.
    '#default_value' => !empty($node->start_date) ? format_date($node->start_date, 'custom', 'Y-m-d H:i:s O') : $default_start_date,
  );
  $form['settings']['end_date'] = array(
    '#type' => 'textfield',
    '#title' => t('Ending date'),
    '#description' => t('The date that the poll closes. Format: %time. Leave blank if you do not want the poll to close automatically.', array('%time' => $time)),
    '#size' => 25,
    '#maxlength' => 25,
    // Use !empty() because 0 signifies that no date should be used.
    '#default_value' => !empty($node->end_date) ? format_date($node->end_date, 'custom', 'Y-m-d H:i:s O') : $default_end_date,
  );

  // Settings available for users with 'administer polls' permission.
  $default_use_list = isset($node->use_list) ? $node->use_list : variable_get('advpoll_electoral_list_'. $type->type, ADVPOLL_ELECTORAL_LIST);
  $default_show_votes = isset($node->show_votes) ? $node->show_votes : variable_get('advpoll_show_votes_'. $type->type, ADVPOLL_SHOW_VOTES);
  $default_writeins = isset($node->writeins) ? $node->writeins : variable_get('advpoll_writeins_'. $type->type, ADVPOLL_WRITEINS);
  $default_show_writeins = isset($node->show_writeins) ? $node->show_writeins : variable_get('advpoll_show_writeins_'. $type->type, ADVPOLL_SHOW_WRITEINS);
  if (user_access('administer polls')) {
    $form['settings']['admin_note'] = array(
      '#value' => '<div id="edit-settings-admin-note" class="description">'. t('The settings below are only available for users with the <em>administer polls</em> permission.') .'</div>',
    );
    $form['settings']['writeins'] = array(
      '#type' => ($node->type != 'advpoll_multirate') ? 'checkbox' : 'hidden',
      '#title' => t('Allow users to cast a write-in vote'),
      '#default_value' => $default_writeins,
      '#description' => t('Allow voters with the "add write-ins" permission to write-in up to one choice each.'),
      '#attributes' => array('class' => 'settings-writeins'),
    );
    $form['settings']['show_writeins'] = array(
      '#type' => ($node->type != 'advpoll_multirate') ? 'checkbox' : 'hidden',
      '#title' => t('Display write-in votes as choices for future voters'),
      '#default_value' => $default_show_writeins,
      '#description' => t('Allow voters to see and choose from previously submitted write-in votes.'),
      '#prefix' => '<div class="edit-settings-show-writeins">',
      '#suffix' => '</div>',
    );
    $form['settings']['use_list'] = array(
      '#type' => 'checkbox',
      '#title' => t('Restrict voting to electoral list'),
      '#description' => t('If enabled, a list of eligible voters will be created and only that group will be able to vote in the poll.'),
      '#default_value' => $default_use_list,
    );
    $form['settings']['show_votes'] = array(
      '#type' => 'checkbox',
      '#title' => t('Show individual votes'),
      '#description' => t('Users with the appropriate permissions will be able to see how each person voted.'),
      '#default_value' => $default_show_votes,
    );
  }
  else {
    // Just pass the values for users without the "administer polls" permission.
    $defaults = array('use_list' => $default_use_list, 'show_votes' => $default_show_votes, 'writeins' => $default_writeins, 'show_writeins' => $default_show_writeins);
    foreach ($defaults as $name => $value) {
      $form['settings'][$name] = array(
        '#type' => 'value',
        '#value' => $value,
      );
    }
  }

  return $form;
}

/**
 * Process advpoll_more_choices form submissions.
 */
function advpoll_more_choices_submit($form, &$form_state) {
  // Based on poll.module
  node_form_submit_build_node($form, $form_state);

  if ($form_state['values']['more_choices']) {
    $n = $_GET['q'] == 'advpoll/js_more_choices' ? 1 : 5;
    $form_state['choice_count'] = count($form_state['values']['choice']) + $n;
  }
}

/**
 * Implementation of hook_form_alter().
 */
function advpoll_form_alter(&$form, $form_state, $form_id) {
  if ($form_id == 'node_type_form' && isset($form['identity']['type'])) {
    $node_type = $form['old_type']['#value'];
    // Display poll settings if this is an advpoll content type.
    if ($form['module']['#value'] == 'advpoll') {
      // Include JS and CSS for the show_writeins setting toggle.
      drupal_add_js(drupal_get_path('module', 'advpoll') .'/advpoll-form.js', 'module');
      drupal_add_css(drupal_get_path('module', 'advpoll') .'/advpoll.css', 'module');
      $form['advpoll'] = array(
        '#type' => 'fieldset',
        '#title' => t('Poll settings'),
        '#collapsible' => TRUE,
      );
      $form['advpoll']['advpoll_choices'] = array(
        '#type' => 'textarea',
        '#title' => t('Default choices'),
        '#default_value' => variable_get('advpoll_choices_'. $node_type, ''),
        '#description' => t('Add one choice per row. This setting can be overridden on the poll edit page.'),
      );
      $form['advpoll']['advpoll_max_choices'] = array(
        '#type' => 'select',
        '#title' => t('Default maximum choices'),
        '#options' => array(0 => t('No limit')) + drupal_map_assoc(array(1, 2, 3, 4, 5)),
        '#default_value' => variable_get('advpoll_max_choices_'. $node_type, ADVPOLL_MAX_CHOICES),
        '#description' => t('The default number of maximum choices for new polls. This setting can be overridden on the poll edit page.'),
      );

      $mode = _advpoll_get_mode($node_type);
      $voting_algorithms = advpoll_algorithms($mode);

      if (count($voting_algorithms) > 1) {
        $form['advpoll']['advpoll_algorithm'] = array(
          '#type' => 'select',
          '#title' => t('Default algorithm'),
          '#options' => $voting_algorithms,
          '#default_value' => variable_get('advpoll_algorithm_'. $node_type, key($voting_algorithms)),
          '#description' => t('Default voting algorithm for calculating the winner.'),
        );
      }

      $form['advpoll']['advpoll_runtime'] = array(
        '#type' => 'select',
        '#title' => t('Default duration'),
        '#default_value' => variable_get('advpoll_runtime_'. $node_type, ADVPOLL_RUNTIME),
        '#options' => array(0 => t('Unlimited')) + drupal_map_assoc(array(86400, 172800, 345600, 604800, 1209600, 1814400, 2419200, 4838400, 9676800, 31536000), 'format_interval'),
        '#description' => t('The date the poll was created is used as start date for the default duration. This setting can be overridden on the poll edit page.'),
      );
      $form['advpoll']['advpoll_writeins'] = array(
        '#type' => 'checkbox',
        '#title' => t('Allow users to cast a write-in vote by default'),
        '#default_value' => variable_get('advpoll_writeins_'. $node_type, ADVPOLL_WRITEINS),
        '#description' => t('Allow voters with the "add write-ins" permission to write-in up to one choice each. Users with the <em>administer polls</em> permission will be able to override this setting.'),
        '#attributes' => array('class' => 'settings-writeins'),
      );
      $form['advpoll']['advpoll_show_writeins'] = array(
        '#type' => 'checkbox',
        '#title' => t('Display write-in votes as choices for future voters by default'),
        '#default_value' => variable_get('advpoll_show_writeins_'. $node_type, ADVPOLL_SHOW_WRITEINS),
        '#description' => t("Allow voters to see and choose from previous voters' write-in votes. Users with the <em>administer polls</em> permission will be able to override this setting."),
        '#prefix' => '<div class="edit-settings-show-writeins">',
        '#suffix' => '</div>',
      );
      $form['advpoll']['advpoll_electoral_list'] = array(
        '#type' => 'checkbox',
        '#title' => t('Use electoral list by default'),
        '#description' => t('Use an electoral list by default for new polls. Users with the <em>administer polls</em> permission will be able to override this setting.'),
        '#default_value' => variable_get('advpoll_electoral_list_'. $node_type, ADVPOLL_ELECTORAL_LIST),
      );
      $form['advpoll']['advpoll_show_votes'] = array(
        '#type' => 'checkbox',
        '#title' => t('Show individual votes by default'),
        '#description' => t('Let users with appropriate permissions see how each person voted by default for new polls. Users with the <em>administer polls</em> permission will be able to override this setting.'),
        '#default_value' => variable_get('advpoll_show_votes_'. $node_type, ADVPOLL_SHOW_VOTES),
      );

      $view_results = array(
        'always' => t('Always'),
        'aftervote' => t('After user has voted'),
        'afterclose' => t('After voting has closed'),
      );

      $form['advpoll']['advpoll_view_results'] = array(
        '#type' => 'radios',
        '#title' => t('Display results'),
        '#description' => t('Determines when users may view the results of the poll.'),
        '#default_value' => variable_get('advpoll_view_results_'. $node_type, ADVPOLL_VIEW_RESULTS),
        '#options' => $view_results,
      );
      $form['advpoll']['advpoll_use_question'] = array(
        '#type' => 'checkbox',
        '#title' => t('Use question field'),
        '#description' => t('Use a dedicated question field instead of a combined question and title field. It is recommended to rename <em>Title field label</em> above to "Title" if this is checked.'),
        '#default_value' => variable_get('advpoll_use_question_'. $node_type, ADVPOLL_USE_QUESTION),
      );
    }
  }
}

/**
 * Implementation of hook_load().
 *
 * Load the votes and poll-specific data into the node object.
 */
function advpoll_load($node) {
  $poll = db_fetch_object(db_query('SELECT * FROM {advpoll} WHERE nid = %d', $node->nid));
  $result = db_query('SELECT cid, weight, label, writein FROM {advpoll_choices} WHERE nid = %d ORDER BY weight', $node->nid);
  $poll->choice = array();
  $poll->writein_choices = 0;
  while ($choice = db_fetch_array($result)) {
    $poll->choice[$choice['cid']] = $choice;
    if ($choice['writein'] == 1) {
      $poll->writein_choices++;
    }
  }
  $poll->choices = count($poll->choice);

  $result = db_query("SELECT value FROM {votingapi_cache} WHERE content_type = 'advpoll' AND content_id = %d AND tag = '_advpoll' AND function = 'total_votes'", $node->nid);
  if ($cache = db_fetch_object($result)) {
    // Found total votes in the cache.
    $poll->votes = $cache->value;
  }
  else {
    $poll->votes = 0;
  }

  list($poll->voted, $poll->cancel_vote) = _advpoll_user_voted($node->nid);
  return $poll;
}

/**
 * Implementation of hook_validate().
 *
 * Validate the editing of an advpoll node. 
 */
function advpoll_validate($node, &$form) {
  // Use form_set_error for any errors.
  $node->choice = array_values($node->choice);

  // TODO: verify if this hack is still needed in Drupal 6.
  // Start keys at 1 rather than 0.
  array_unshift($node->choice, '');
  unset($node->choice[0]);

  // Check for at least two choices.
  $real_choices = 0;

  // TODO: take out _POST
  foreach ($_POST['choice'] as $i => $choice) {
    if ($choice['label'] != '') {
      $real_choices++;
    }
  }

  if ($real_choices < 2) {
    form_set_error("choice][$real_choices][label", t('You must fill in at least two choices.'));
  }

  // Validate max choices since it has #DANGEROUS_SKIP_CHECK set to true.
  if ($node->settings['max_choices'] < 0) {
    form_set_error('settings][max_choices]', t('Maximum choices must be a non-negative integer.'));
  }

  if ($node->settings['max_choices'] > $real_choices) {
    form_set_error('settings][max_choices]', t('Maximum choices cannot be larger than the number of choices submitted.'));
  }
    
  // Validate dates.
  if (!empty($node->settings['start_date']) && strtotime($node->settings['start_date']) <= 0) {
    form_set_error('settings][start_date', t('You have to specify a valid starting date.'));
  }
  if (!empty($node->settings['end_date']) && strtotime($node->settings['end_date']) <= 0) {
    form_set_error('settings][end_date', t('You have to specify a valid ending date.'));
  }
  if (!empty($node->settings['end_date']) && $node->settings['end_date'] < $node->settings['start_date']) {
    form_set_error('settings][end_date', t('Ending date cannot be before the starting date.'));
  }
}

/**
 * Implementation of hook_insert().
 *
 * This is called upon node creation.
 */
function advpoll_insert($node) {
  $mode = _advpoll_get_mode($node->type);
  db_query("INSERT INTO {advpoll} (nid, mode, use_list, active, max_choices, algorithm, show_votes, start_date, end_date, writeins, show_writeins, question, max_points, display_overall_rating, display_avg_results, low_rating_label, high_rating_label, overall_rating_label) VALUES (%d, '%s', %d, %d, %d, '%s', %d, '%s', '%s', %d, %d, '%s', %d, %d, %d, '%s', '%s', '%s')", $node->nid, $mode, $node->settings['use_list'], !$node->settings['close'], $node->settings['max_choices'], $node->settings['algorithm'], $node->settings['show_votes'], $node->settings['start_date'] ? strtotime($node->settings['start_date']) : 0, $node->settings['end_date'] ? strtotime($node->settings['end_date']) : 0, $node->settings['writeins'], $node->settings['show_writeins'], isset($node->question) ? $node->question : '', $node->settings['max_points'], $node->settings['display_overall_rating'], $node->settings['display_avg_results'], $node->settings['low_rating_label'], $node->settings['high_rating_label'], $node->settings['overall_rating_label']);

  // Insert the choices.
  _advpoll_insert_choices($node);
}

/**
 * Implementation of hook_update().
 *
 * This is called upon node edition.
 */
function advpoll_update($node) {

  db_query("UPDATE {advpoll} SET active = %d, max_choices = %d, algorithm = '%s', use_list = %d, show_votes = %d, start_date = '%s', end_date = '%s', writeins = %d, show_writeins = %d, question = '%s', max_points = %d, display_overall_rating = %d, display_avg_results = %d, low_rating_label = '%s', high_rating_label = '%s', overall_rating_label = '%s' WHERE nid = %d", !$node->settings['close'], $node->settings['max_choices'], $node->settings['algorithm'], $node->settings['use_list'], $node->settings['show_votes'], $node->settings['start_date'] ? strtotime($node->settings['start_date']) : 0, $node->settings['end_date'] ? strtotime($node->settings['end_date']) : 0, $node->settings['writeins'], $node->settings['show_writeins'], isset($node->question) ? $node->question : '', $node->settings['max_points'], $node->settings['display_overall_rating'], $node->settings['display_avg_results'], $node->settings['low_rating_label'], $node->settings['high_rating_label'], $node->settings['overall_rating_label'], $node->nid);

  _advpoll_insert_choices($node);
  votingapi_recalculate_results('advpoll', $node->nid);
}

/**
 * Implementation of hook_view().
 */
function advpoll_view($node, $teaser = FALSE, $page = FALSE) {
  drupal_add_css(drupal_get_path('module', 'advpoll') .'/advpoll.css', 'module');
  $status = _advpoll_is_active($node, TRUE);
  
  // Add question to content if defined.
  if ($node->question !== '') {
    $node->content['question'] = array(
      '#weight' => 1,
      '#value' => theme('advpoll_question', check_plain($node->question)),
    );
  }

  if ($node->build_mode == NODE_BUILD_PREVIEW) {
    // Previewing a node, so display voting form instead of results.
    $poll = drupal_get_form('advpoll_voting_'. _advpoll_get_mode($node->type) .'_form', $node, $teaser, $page, $status);
  }
  else if (!$node->voted && arg(2) != 'results' && ($status == 'open' || $status == 'pending')) {
  // OLD: else if ((!$node->voted && arg(2) != 'results' && ($status == 'open' || $status == 'pending')) || $_POST['op'] == 'Vote') {

    // User hasn't voted, we're not on the results tab and poll is open or
    // opening in the future. Also, we check the $_POST array if the user tried
    // to submit a vote, so we can validate and give an error if the user has
    // already voted on the poll.
    $poll = drupal_get_form('advpoll_voting_'. $node->mode .'_form', $node, $teaser, $page, $status);

    static $add_js = TRUE;
    if ($add_js) {
      // Add javascript for posting voting forms with Ajax.
      drupal_add_js(drupal_get_path('module', 'advpoll') .'/advpoll-vote.js', 'module');
      drupal_add_js('misc/jquery.form.js', 'module');
      $add_js = FALSE;
    }
  }
  else {
    // Show results (the user has voted, poll is closed or poll has passed).
    if (user_access('show vote results')) {
      $poll = advpoll_view_results($node, $teaser, $page);
    }
    elseif (user_access('cancel own vote')) {
      $poll = _advpoll_show_cancel_form($node);
    }
  }

  $node->content['poll'] = array(
    '#weight' => 2,
    '#value' => $poll,
  );
  return node_prepare($node, $teaser);
}

/**
 * Implementation of hook_delete().
 */
function advpoll_delete($node) {
  db_query('DELETE FROM {advpoll} WHERE nid = %d', $node->nid);
  db_query('DELETE FROM {advpoll_choices} WHERE nid = %d', $node->nid);
  db_query('DELETE FROM {advpoll_electoral_list} WHERE nid = %d', $node->nid);

  // TODO: These should be converted to a votingapi method eventually.
  db_query("DELETE FROM {votingapi_vote} WHERE content_id = %d AND content_type = 'advpoll'", $node->nid);
  db_query("DELETE FROM {votingapi_cache} WHERE content_id = %d AND content_type = 'advpoll'", $node->nid);
}

/**
 * Implementation of VotingAPI's hook_calculate.
 * 
 * Recalculate results whenever a vote is added or removed.
 */
function advpoll_votingapi_results_alter(&$cache, $content_type, $content_id) {
  // Make sure it's an Advanced Poll content type.
  if ($content_type == 'advpoll') {
    // Don't load the node from cache in case the mode or algorithm changed.
    $node = node_load($content_id, NULL, TRUE);
    $mode = _advpoll_get_mode($node->type);
    $function = 'advpoll_calculate_results_'. $mode;
    if (function_exists($function)) {
      $function($cache, $node);
    }
    cache_clear_all();
  }
}

/**
 * Check if a user has voted on a poll.
 *
 * @return Array indicating if user voted and, if so, if the vote is cancellable.
 */
function _advpoll_user_voted($nid) {
  global $user;
  $voted = FALSE;
  $cancel_vote = FALSE;

  if ($user->uid) {
    // Voter is logged in.
    $voted = count(votingapi_select_votes(array('uid' => $user->uid, 'content_id' => $nid)));
    if ($voted) {
      $cancel_vote = TRUE;
    }
  }
  else {
    // Voter is anonymous.
    $voted = count(votingapi_select_votes(array('vote_source' => ip_address(), 'content_id' => $nid, 'uid' => 0)));
    if ($voted) {
      // Found a vote in the database.
      $cancel_vote = TRUE;
    }
  }
  return array($voted, $cancel_vote);
}

/**
 * Build electorial list form.
 */
function advpoll_electoral_list_form(&$form_state, $nid) {
  $form['electoral_list'] = array(
    '#type' => 'fieldset',
    '#tree' => TRUE,
    '#title' => t('Administer electoral list'),
    '#collapsible' => TRUE,
    '#weight' => 2,
  );
  $form['electoral_list']['add_user'] = array(
    '#type' => 'textfield',
    '#title' => t('Add user'),
    '#size' => 40,
    '#description' => t('Add an individual user to the electoral list.'),
  );
  
  // Enable autocompletion if user has required permission.
  if (user_access('access user profiles')) {
    $form['electoral_list']['add_user']['#autocomplete_path'] = 'user/autocomplete';
  }

  // List all roles with "vote on polls" permission, but don't include anonymous users.
  $result = db_query("SELECT r.name, r.rid FROM {role} r LEFT JOIN {permission} p ON p.rid = r.rid WHERE p.perm LIKE '%vote on polls%' AND r.rid <> 1 ORDER BY r.name");
  $role_options = array(0 => t('(Select a role)'));
  while ($role = db_fetch_object($result)) {
    $role_options[$role->rid] = $role->name;
  }

  $form['electoral_list']['add_role'] = array(
    '#type' => 'select',
    '#title' => t('Add users by role'),
    '#description' => t('Only roles that have the "vote on polls" permission are listed.'),
    '#options' => $role_options,
  );
  $form['electoral_list']['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Add to electoral list'),
  );
  $form['electoral_list']['reset'] = array(
    '#type' => 'button',
    '#value' => t('Clear electoral list'),
  );

  $form['nid'] = array('#type' => 'hidden', '#value' => $nid);
  return $form;
}

/**
 * Validate changes to the electoral list.
 */
function advpoll_electoral_list_form_validate($form, &$form_state) {
  if ($form_state['values']['op'] == t('Clear electoral list')) {
    if (user_access('administer polls')) {
      db_query('DELETE FROM {advpoll_electoral_list} WHERE nid = %d', $form_state['values']['nid']);
      drupal_set_message(t('Electoral list cleared.'));
      return;
    }
  }

  $add_user = $form_state['values']['electoral_list']['add_user'];
  if ($add_user) {
    // Check that the user exists
    $result = db_query("SELECT uid FROM {users} WHERE name = '%s'", $add_user);
    if (!db_fetch_object($result)) {
      form_set_error('electoral_list][add_user', t('User %user does not exist.', array('%user' => $add_user)));
      return FALSE;
    }
  }
}

/**
 * Process advpoll_electorial_list form submissions.
 *
 * Submit changes to the electoral list.
 */
function advpoll_electoral_list_form_submit($form, &$form_state) {
  $add_user = $form_state['values']['electoral_list']['add_user'];
  if ($add_user) {
    db_query("REPLACE INTO {advpoll_electoral_list} (nid, uid) SELECT '%d', u.uid FROM {users} u WHERE u.name = '%s'", $form_state['values']['nid'], $add_user);
    drupal_set_message(t('%user added to electoral list.', array('%user' => $add_user)));
  }

  $add_role = $form_state['values']['electoral_list']['add_role'];
  if ($add_role) {
    // Get the current electoral list.
    $result = db_query('SELECT uid FROM {advpoll_electoral_list} WHERE nid = %d', $form_state['values']['nid']);
    $current_list = array(0);
    while ($user = db_fetch_object($result)) {
      $current_list[] = $user->uid;
    }

    $user_in_string = implode(',', $current_list);
    // Check if all authenticated users should be added.
    $is_authenticated = db_result(db_query("SELECT COUNT(*) FROM {role} r WHERE r.name = 'authenticated user' AND r.rid = %d", $add_role));
    if ($is_authenticated) {
      // Special case: any authenticated user can vote.
      // Add all current users to electoral list.
      $result = db_query("INSERT INTO {advpoll_electoral_list} (nid, uid) SELECT '%d', u.uid FROM {users} u WHERE u.uid NOT IN('%s')", $form_state['values']['nid'], $user_in_string);
    }
    else {
      // Insert new users into the electoral_list based on the role chosen.
      $result = db_query("INSERT INTO {advpoll_electoral_list} (nid, uid) SELECT '%d', u.uid FROM {users} u LEFT JOIN {users_roles} ur ON u.uid = ur.uid WHERE ur.rid = %d AND u.uid NOT IN('%s')", $form_state['values']['nid'], $add_role, $user_in_string);
    }
    drupal_set_message(format_plural(db_affected_rows($result), 'Added 1 user to the electoral list.', 'Added @count users to the electoral list.'));
  }
}

/**
 * Helper function to abstract view results checking.
 */
function _advpoll_can_view_results($node) {
  $view_results = variable_get('advpoll_view_results_'. $node->type, ADVPOLL_VIEW_RESULTS);
  return (!_advpoll_is_active($node)  // Node is closed
        || ($node->voted && $view_results == 'aftervote') // User voted
        || ($view_results == 'always')); // All can view
}

/**
 * Helper function to display 'cancel vote' button if user has voted.
 */
function advpoll_cancel_form(&$form_state, $nid) {
  $form['#action'] = url('advpoll/cancel/'. $nid);
  $form['submit'] = array('#type' => 'submit', '#value' => t('Cancel your vote'));
  return $form;
}

/**
 * Helper function to check if a poll is active.
 */
function _advpoll_is_active($node, $return_status = FALSE) {
  $active = TRUE;
  $status = 'open';
  $start_date = $node->start_date;
  $end_date = $node->end_date;

  // Check if poll is closed.
  if (!$node->active) {
    $active = FALSE;
    $status = 'closed';
  }

  if ($active && $start_date > 0) {
    // Check that start date is in the past.
    if (!$active = time() >= $start_date) {
      $status = 'pending';
    }
  }

  if ($active && ($end_date > 0)) {
    // Check that end date is in the future.
    if (!$active = time() < $end_date) {
      $status = 'passed';
    }
  }
  return $return_status ? $status : $active;
}

/**
 * Process advpoll_binary_node form submissions.
 *
 * Update the choices added or removed when editing a binary poll
 */
function advpoll_binary_node_form_submit($form, &$form_state) {
  // Get the submitted (modified) choices from _POST and replace them in the form values
  // Note: we pass choice data via _POST to allow for dynamic addition of choices.
  // TODO: Implement AHAH support for advpoll node form
  if (isset($_POST['choice'])) {
    $form_state['values']['choice'] = $_POST['choice'];
  }
}

/**
 * Process advpoll_ranking_node form submissions.
 *
 * Update the choices added or removed when editing a ranking poll
 */
function advpoll_ranking_node_form_submit($form, &$form_state) {
  // Get the submitted (modified) choices from _POST and replace them in the form values
  // Note: we pass choice data via _POST to allow for dynamic addition of choices.
  // TODO: Implement AHAH support for advpoll node form
  if (isset($_POST['choice'])) {
    $form_state['values']['choice'] = $_POST['choice'];
  }
}

/**
 * Insert/update the choices for a poll.
 *
 * Note: we pass choice data via _POST to allow for dynamic addition of choices.
 * Drupal 6 AHAH support will let us switch to a clean implementation.
 */
function _advpoll_insert_choices($node) {
  $nid = $node->nid;
  $weight = 0;
  $seen_ids = array();
  foreach ($node->choice as $index => $choice) {
    if ($choice['label'] != '') {
      // Mark this choice id as being seen.
      $choice_exist = db_result(db_query("SELECT COUNT(cid) FROM {advpoll_choices} WHERE nid = %d AND cid = %d", $nid, $index));
      if (!$choice_exist) {
        db_query("INSERT INTO {advpoll_choices} (nid, label, weight) VALUES (%d, '%s', %d)", $nid, $choice['label'], $weight);
        $seen_id = db_last_insert_id('advpoll_choices', 'cid');
      }
      else {
        db_query("UPDATE {advpoll_choices} SET label = '%s', weight = %d WHERE cid = %d", $choice['label'], $weight, $index);
        $seen_id = $index;
      }
      $seen_ids[$seen_id] = 1;
      $weight++;
    }
  }

  $all_ids_query = db_query("SELECT cid, label FROM {advpoll_choices} WHERE nid = %d", $nid);
  $all_ids = array();
  while ($row = db_fetch_array($all_ids_query)) {
      $all_ids[$row['cid']] = array('label' => $row['label']);
  }

  // Delete any choices that were removed (either dynamically or by submitting
  // a blank label).
  if (isset($node->choice)) {
    foreach ($all_ids as $id => $choice) {
      if (!isset($seen_ids[$id])) {
        db_query('DELETE FROM {advpoll_choices} WHERE cid = %d', $id);
        drupal_set_message(t('Deleted choice %label', array('%label' => $choice['label'])), 'status');
        // We could potentially also delete any votes for this choice, but let's
        // leave them in the database so that one can go back and check if anyone
        // voted for a deleted choice.
      }
    }
  }
}

function _advpoll_get_mode($node_type) {
  if ($node_type) {
    $mode = explode('advpoll_', $node_type, 2);
    return $mode[1];
  }
  else {
    drupal_set_message(t('No mode specified for content type %type.', array('%type' => $node_type)), 'error');
    return '';
  }
}

/**
 * Minimal clear votes form for the votes tab.
 */
function advpoll_clear_votes_form(&$form_state, $nid) {
  $form = array();
  $form['reset'] = array(
    '#value' => t('Clear all votes'),
    '#type' => 'submit',
  );
  $form['#redirect'] = 'node/'. $nid . '/votes/clear';
  return $form;
}

/**
 * Display a clear votes confirmation form.
 */
function advpoll_clear_votes_confirm_form(&$form_state, $nid) {
  $node = node_load($nid);
  $form = array();
  $form['#nid'] = $node->nid;
  $confirm_question = t('Are you sure you want to clear all votes for %title?', array('%title' => $node->title));
  $form['question'] = array('#value' => '<h2>' . $confirm_question . '</h2>');
  $form = confirm_form($form, $confirm_question, 'node/'. $node->nid . '/votes', t('This will delete all votes that have been cast for the poll.'), t('Clear all votes'), t('Cancel'));
  // Override the default theming of confirmation forms.
  // TODO: need to theme this form better. 
  unset($form['#theme']);
  return $form;
}

/**
 * Process advpoll_clear_votes_confirm form submissions.
 *
 * Update the choices added or removed when editing a node
 * Clear all votes once the confirmation is given.
 */
function advpoll_clear_votes_confirm_form_submit($form, &$form_state) {
  if ($form_state['values']['confirm']) {
    $nid = $form['#nid'];
    if ($node = node_load($nid)) {
      // Delete any votes for the poll.
      db_query("DELETE FROM {votingapi_vote} WHERE content_type = 'advpoll' AND content_id = %d", $node->nid);
      // Delete any write-in choices.
      db_query('DELETE FROM {advpoll_choices} WHERE writein = 1 AND nid = %d', $node->nid);
      votingapi_recalculate_results('advpoll', $node->nid);
      drupal_set_message(t('Votes have been cleared.'));
      watchdog('content', 'Cleared all poll votes (%num_votes).', array('%num_votes' => $node->votes), WATCHDOG_NOTICE, l(t('view'), 'node/' . $node->nid));
    }
    $form_state['redirect'] = 'node/'. $node->nid;
  }
}

function _advpoll_block_resultslink($node) {
  return array(
    'title' => t('Results'),
    'href' => 'node/'. $node->nid .'/results',
    'attributes' => array('title' => t('View the current poll results.')),
  );
}

/**
 * Theme an optional question.
 */
function theme_advpoll_question($question) {
  return '<p class="poll-question">'. $question .'</p>';
} 

function theme_advpoll_results($title, $results, $votes, $links, $nid, $voted, $cancel_vote) {
  $output = '<div class="poll">';
  if ($results) {
    $output .= $results;
    $output .= '<div class="total">'. t('Total voters: %votes', array('%votes' => $votes)) .'</div>';
  }
  else {
    $output .= '<p class="message">'. t('No votes have been recorded for this poll.') .'</p>';
  }
  $output .= '</div>';
  return $output;
}

function _advpoll_show_cancel_form($node) {
  $output = '';
  if ($node->voted && $node->cancel_vote && user_access('cancel own vote') && _advpoll_is_active($node)) {
    $output .= drupal_get_form('advpoll_cancel_form', $node->nid);
  }
  return $output;
}

function theme_advpoll_bar($title, $percentage, $votes, $choice = NULL) {
  $output  = '<div class="text">'. $title . ($choice && $choice['writein'] ? ' '. t('(write-in)') : '') .'</div>';
  $output .= '<div class="bar"><div style="width: '. $percentage .'%;" class="foreground"></div></div>';
  $output .= '<div class="percent">'. $percentage .'% <span class="votes">('. $votes .')</span></div>';
  return $output;
}

function _advpoll_vote_response($node, $form_state) {
  $msg = t('Your vote was registered.');
  // Ajax response
  if ($form_state['values']['ajax']) {
    // Unset the array of choices so duplicates aren't shown.
    unset($node->choice);
    // Get all choices from database. This is necessary to get information about
    // newly submitted write-in choices.
    $result = db_query('SELECT cid, weight, label, writein FROM {advpoll_choices} WHERE nid = %d ORDER BY weight', $node->nid);
    while ($choice = db_fetch_array($result)) {
      $node->choice[$choice['cid']] = $choice;
    }
    // Update the number of choices.
    $node->choices = count($node->choice);
    // Get updated total number of votes from database.
    $result = db_query("SELECT value FROM {votingapi_cache} WHERE content_type = 'advpoll' AND content_id = %d AND tag = '_advpoll' AND function = 'total_votes'", $node->nid);
    if ($cache = db_fetch_object($result)) {
      $node->votes = $cache->value;
    }
    else {
      $node->votes = 0;
    }

    list($node->voted, $node->cancel_vote) = _advpoll_user_voted($node->nid);
    $ajax_output = '';
    if (user_access('show vote results')) {
      $ajax_output .= advpoll_view_results($node, NULL, NULL);
    }
    elseif (user_access('cancel own vote')) {
      $ajax_output .= _advpoll_show_cancel_form($node);
    }
    // Remove linebreaks as they will break jQuery's insert-HTML methods.
    $ajax_output = str_replace("\n", '', $ajax_output);
    drupal_set_header('Content-Type: text/plain; charset=utf-8');
    print drupal_to_js(array('statusMsgs' => '<div class="messages status">'. $msg .'</div>', 'response' => $ajax_output));
    exit();
  }
  // Usual response.
  else {
    drupal_set_message($msg);
  }
}

/**
 * Show results of the vote.
 *
 * This calls the appropriate vote results function, depending on the
 * mode. It will call advpoll_view_results_$mode, similarly to
 * advpoll_view_voting().
 */
function advpoll_view_results(&$node, $teaser, $page) {
  $output = '';
  $mode = _advpoll_get_mode($node->type);
  if (_advpoll_can_view_results($node)) {
    if (function_exists('advpoll_view_results_'. $mode)) {
      $results = call_user_func('advpoll_view_results_'. $mode, $node, $teaser, $page);
      $output .= theme('advpoll_results', check_plain($node->title), $results['results'], $results['votes'], isset($node->links) ? $node->links : array(), $node->nid, $node->voted, $node->cancel_vote);
    }
  }
  $output .= _advpoll_show_cancel_form($node);
  return $output;
}

/**
 * Check if user is eligible to vote in this poll.
 */
function advpoll_eligible($node, $uid = NULL) {
  global $user;
  if (!isset($uid)) {
    $uid = $user->uid;
  }

  if ($node->use_list) {
    $eligible = db_result(db_query('SELECT COUNT(*) FROM {advpoll_electoral_list} WHERE nid = %d AND uid = %d', $node->nid, $uid));
  }
  else {
    $eligible = user_access('vote on polls');
  }
  return $eligible;
}

function advpoll_algorithms($mode) {
  return call_user_func('advpoll_algorithms_'. $mode);
}

/**
 * Load the available modes.
 *
 * This scans the modes subdirectory to find mode.inc files, where
 * mode is considered to be the mode name. Found files are loaded and
 * added to the mode list.
 */
function _advpoll_list_modes() {
  static $advpoll_modes;
  if (!$advpoll_modes) {
    $files = file_scan_directory(dirname(__FILE__) .'/modes/', '^([^\.].*)\.inc$', array('.', '..', 'CVS'), 0, FALSE);
    foreach ($files as $file) {
      require_once($file->filename);
      $mode = $file->name;
      if (function_exists('advpoll_info_'. $mode)) {
        $advpoll_modes[$mode] = call_user_func('advpoll_info_'. $mode);
      }
    }
  }
  return $advpoll_modes;
}

/**
 * Helper function for rich text in choices.
 *
 * We strip out the paragraphs which are not allowed within the label element
 * and created by check_markup() when "Line break converter"-filter is used.
 */
function _advpoll_choice_markup($text, $format = FILTER_FORMAT_DEFAULT, $check = TRUE) {
  $text = check_markup($text, $format, $check);
  $text = str_replace(array('<p>', '</p>'), '', $text);
  $text = trim($text);
  return $text;
}

/**
 * Wrapper function around form_set_error() to support validating of Ajax voting.
 */
function _advpoll_form_set_error($name = NULL, $message = '', $ajax = FALSE) {
  if ($ajax) {
    drupal_set_header('Content-Type: text/plain; charset=utf-8');
    print drupal_to_js(array('errors' => '<div class="messages error">'. $message .'</div>'));
    exit;
  }
  else {
    return form_set_error('choice[', $message);
  }
}

/**
 * Voting form validation logic specific to writeins. This has been abstracted
 * away from includes in the modes directory.
 */
function _advpoll_writeins_voting_form_validate($node, $writein_option, $writein_text, $ajax) {
  // Do write-in specific checks if write-ins are enabled and user has permission.
  if ($node->writeins && user_access('add write-ins')) {
    // Something is in the write-in textbox.
    if ($writein_text) {
      $writein_choice_lower = strtolower($writein_text);
      foreach ($node->choice as $i => $value) {
        // Check that user isn't writing in an existing visible choice. (User is
        // writing in an existing choice and either write-ins are all being 
        // displayed or the existing choice is not a write-in).
        if ((strtolower($value['label']) == $writein_choice_lower) && ($node->show_writeins || !$value['writein'])) {
          _advpoll_form_set_error('writein_choice', t("A write-in vote can not be for an existing choice. Select the choice's option instead."), $ajax);
        }
      }
    }

    // The write-in option is selected and there is nothing in the write-in textbox.
    if ($writein_option && !$writein_text) {
      _advpoll_form_set_error('writein_choice', t('If the "write-in" option is selected, a choice must be written in.'), $ajax);
    }

    // The write-in option is not selected, but there is something in the write-in textbox.
    if (!$writein_option && $writein_text) {
      _advpoll_form_set_error('writein_choice', t('If a choice is written in, the "write-in" option must be selected.'), $ajax);
    }
  }
}

/**
 * Handle JavaScript voting.
 */
function advpoll_js_vote() {
  // TODO : fix this function.
  $form_state = array();
  $form_build_id = $_POST['form_build_id'];
  if (!$form = form_get_cache($form_build_id, $form_state)) {
    exit();
  }
}

/**
 * Voting form submission logic specific to writeins. This has been abstracted 
 * away from includes in the modes directory.
 */
function _advpoll_writeins_voting_form_submit($node, $form_state, &$votes, $vote_value = 1) {
  // A write-in vote is being made.
  if (isset($form_state['values']['writein_choice']) && $form_state['values']['writein_choice']) {
    // Check if someone has previously voted for this choice.
    $result = db_query("SELECT cid FROM {advpoll_choices} WHERE nid = %d AND LOWER(label) = LOWER('%s')", $node->nid, $form_state['values']['writein_choice']);
    $db_vote = db_fetch_object($result);
    // If there's more than one match, redo the query, being more exact.
    if ($db_vote && $second_vote = db_fetch_object($result)) {
      $result = db_query("SELECT cid FROM {advpoll_choices} WHERE nid = %d AND label = '%s'", $node->nid, $form_state['values']['writein_choice']);      
      $db_vote = db_fetch_object($result);
    }
    // If there is at least one match, add a vote for the first one returned. It
    // should be rare to find more than one choice for any one node with a given
    // label.
    if ($db_vote) {
      $existing_choice = $db_vote->cid;
      // Set a vote
      $vote = array();
      // TODO: confirm this works for ranking polls.
      $vote['value'] = $vote_value;
      $vote['tag'] = $existing_choice;
      $vote['value_type'] = 'option';
      $vote['content_type'] = 'advpoll';
      $vote['content_id'] = $node->nid;
      $votes[] = $vote;
    }
    // This write-in choice has not been previously voted for.
    else {
      // Get highest weight for this node.
      $highest_weight = db_result(db_query("SELECT MAX(weight) FROM {advpoll_choices} WHERE nid = %d", $node->nid));
      $next_weight = $highest_weight ? $highest_weight + 1 : 1;

      // Insert new choice. We do a check_plain() on the label to ensure that
      // there is no possibility of insecure data getting into the database;
      // if HTML is needed the admin can edit the writein choice manually.
      db_query("INSERT INTO {advpoll_choices} (nid, label, weight, writein) VALUES (%d, '%s', %d, 1)", $node->nid, check_plain($form_state['values']['writein_choice']), $next_weight);

      // Get newest choice id.
      $next_cid = db_result(db_query("SELECT cid FROM {advpoll_choices} WHERE nid = %d AND label = '%s'", $node->nid, $form_state['values']['writein_choice']));
      
      // Add vote
      $vote = array();
      // TODO: confirm this works for ranking polls.
      $vote['value'] = $vote_value;
      $vote['tag'] = $next_cid;
      $vote['value_type'] = 'option';
      $vote['content_type'] = 'advpoll';
      $vote['content_id'] = $node->nid;
      $votes[] = $vote;
    }
  }
}

function advpoll_writein_merge_form(&$form_state, $node) {
  $form = array();
  $form['fieldset'] = array(
    '#type' => 'fieldset',
    '#collapsible' => FALSE,
    '#title' => t('Merge write-ins'),
  );
  $form['fieldset']['note'] = array(
    '#value' => '<div class="description">'. t('This will delete the write-in and change any votes for it into votes for the selected chocie.') .'</div>',
  );
  $form['fieldset']['merge'] = array(
    '#prefix' => '<div class="container-inline">'. t('Merge') .' ',
    '#suffix' => '</div>',
  );
  $writein_list = array();
  $choice_list = array();
  foreach ($node->choice as $index => $choice) {
    $choice_list[$index] = $choice['label'];
    if ($choice['writein']) {
      $writein_list[$index] = $choice['label'];
    }
  }
  $form['fieldset']['merge']['source'] = array(
    '#type' => 'select',
    '#options' => $writein_list,
  );
  $form['fieldset']['merge']['into'] = array(
    '#value' => t(' into '),
  );
  $form['fieldset']['merge']['destination'] = array(
    '#type' => 'select',
    '#options' => $choice_list,
  );
  $form['fieldset']['merge']['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Merge'),
  );
  $form['nid'] = array(
    '#type' => 'value',
    '#value' => $node->nid,
  );
  $form['#node'] = $node;
  return $form;
}

function advpoll_writein_merge_form_validate($form, &$form_state) {
  if ($form_state['values']['source'] == $form_state['values']['destination']) {
    form_set_error('destination', t('The write-in cannot be merged into itself.'));
  }
}

/**
 * Process advpoll_writein_merge form submissions.
 */
function advpoll_writein_merge_form_submit($form, &$form_state) {
  // Get a list of votes in this node.
  $node = $form['#node'];
  $raw_votes = db_query('SELECT * FROM {votingapi_vote} WHERE content_id = %d', $form_state['values']['nid']);
  $voters = array();
  $affected_voters = array();
  while ($vote = db_fetch_object($raw_votes)) {
    $key = $vote->uid .'-'. $vote->vote_source;
    if (!isset($voters[$key])) {
      $voters[$key] = array();
    }
    array_push($voters[$key], $vote);
    if ($vote->tag == $form_state['values']['source']) {
      // This voter is affected by the merge; save the index of the source vote.
      $affected_voters[$key] = count($voters[$key]) - 1;
    }
  }
  // Now fix the affected voters.
  foreach ($affected_voters as $key => $source_index) {
    // Find out if they voted for the destination or not.
    $voted_for_destination = FALSE;
    foreach ($voters[$key] as $index => $vote) {
      if ($vote->tag == $form_state['values']['destination']) {
        $voted_for_destination = TRUE;
        break;
      }
    }
    if ($voted_for_destination) {
      // Since they already voted for the destination choice,  delete the vote
      // for the source.
      db_query('DELETE FROM {votingapi_vote} WHERE vote_id = %d AND tag = %d', $voters[$key][$index]->vote_id, $form_state['values']['source']);
    }
    else {
      // They didn't already vote for the destination, so transfer the vote for
      // the source to the destination.
      db_query('UPDATE {votingapi_vote} SET tag = %d WHERE vote_id = %d AND tag = %d', $form_state['values']['destination'], $voters[$key][$index]->vote_id, $form_state['values']['source']);
    }
  }

  // Delete the merged choice.
  db_query('DELETE FROM {advpoll_choices} WHERE cid = %d', $form_state['values']['source']);
  votingapi_recalculate_results('advpoll', $form_state['values']['nid']);
  drupal_set_message(t('Write-in merged.'));
  // Unset destination form element so that drupal_goto() doesn't use it
  // mistakenly.
  unset($_REQUEST['destination']);
  $writeins_remaining = FALSE;
  foreach ($node->choice as $choice) {
    if ($choice['writein'] && $choice['cid'] != $form_state['values']['source']) {
      $writeins_remaining = TRUE;
      break;
    }
  }
  drupal_goto('node/'. $form_state['values']['nid'] . ($writeins_remaining ? '/writeins' : ''));
}

function advpoll_writein_promote_form(&$form_state, $node) {
  $form = array();
  $form['fieldset'] = array(
    '#type' => 'fieldset',
    '#collapsible' => FALSE,
    '#title' => t('Promote write-ins'),
  );
  $form['fieldset']['note'] = array(
    '#value' => '<p class="description">'. t('Write-ins can be converted to regular choices. This is useful if users cannot see past write-ins but you want to promote specific write-ins so that they can be seen by users who vote in the future.') .'</p>',
  );
  $writein_list = array();
  foreach ($node->choice as $index => $choice) {
    if ($choice['writein']) {
      $writein_list[$index] = $choice['label'];
    }
  }

  $form['fieldset']['promote'] = array(
    '#type' => 'checkboxes',
    '#options' => $writein_list,
  );
  $form['fieldset']['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Promote'),
  );
  $form['nid'] = array(
    '#type' => 'value',
    '#value' => $node->nid,
  );
  return $form;
}

/**
 * Process advpoll_writein_promote form submissions.
 */
function advpoll_writein_promote_form_submit($form, &$form_state) {
  if (count($form_state['values']['promote'])) {
    db_query('UPDATE {advpoll_choices} SET writein = 0 WHERE nid = %d AND cid IN(%s)', $form_state['values']['nid'], implode(', ', $form_state['values']['promote']));
    drupal_set_message(format_plural(count($form_state['values']['promote']), 'Write-in promoted.', 'Write-ins promoted.'));
  }
  drupal_goto('node/'. $form_state['values']['nid']);
}

/**
 * Implementation of hook_theme().
 */
function advpoll_theme() {
  return array(
    'advpoll_page' => array(
      'arguments' => array('' => '')
    ),
    'advpoll_block_latest_poll' => array(
      'arguments' => array(),
    ),
    'advpoll_results' => array(
      'arguments' => array(
        'title' => '',
        'results' => '',
        'votes' => '',
        'links' => '',
        'nid' => '',
        'voted' => '',
        'cancel_vote' => '',
      )
    ),
    'advpoll_bar' => array(
      'arguments' => array(
        'title' => '',
        'percentage' => '',
        'votes' => '',
        'choice' => NULL,
      )
    ),
    'advpoll_voting_ranking_form' => array(
      'template' => 'advpoll-display-ranking-form',
      'file' => 'modes/ranking.inc',
      'arguments' => array(
        'form' => NULL,
      )
    ),
    'advpoll_voting_binary_form' => array(
      'template' => 'advpoll-display-binary-form',
      'file' => 'modes/binary.inc',
      'arguments' => array(
        'form' => NULL,
   )
    ),
    'advpoll_voting_multirate_form' => array(
      'template' => 'advpoll-display-multirate-form',
      'file' => 'modes/multirate.inc',
      'arguments' => array(
        'form' => NULL,
      )
     ),
   );
 }

/**
 * AHAH handling of the more choices button.
 * 
 * Based on http://drupal.org/node/331941
 */
function advpoll_js_more_choices() {
  // We're starting in step #3, preparing for #4.
  $form_state = array('storage' => NULL, 'submitted' => FALSE);
  $form_build_id = $_POST['form_build_id'];
  // Step #4.
  $form = form_get_cache($form_build_id, $form_state);

  // Preparing for #5.
  $args = $form['#parameters'];
  $form_id = array_shift($args);
  $form_state['post'] = $form['#post'] = $_POST;
  $form['#programmed'] = $form['#redirect'] = FALSE;

  // Step #5.
  drupal_process_form($form_id, $form, $form_state);

  // Step #6 and #7 and #8.
  $form = drupal_rebuild_form($form_id, $form_state, $args, $form_build_id);

  // Step #9.
  $choice_form = $form['choice_wrapper']['choice'];
  unset($choice_form['#prefix'], $choice_form['#suffix']);
  $output = theme('status_messages') . drupal_render($choice_form);

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

/**
 * Implementation of hook_views_api().
 */
function advpoll_views_api() {
  return array(
    'api' => 2,
    'path' => drupal_get_path('module', 'advpoll') .'/views',
  );
}


/**
 * Implementation of hook_votingapi_relationships().
 */
function advpoll_votingapi_relationships() {
  $relationships[] = array(
    'description' => t('Advanced Poll'),
    'content_type' => 'advpoll',
    'base_table' => 'node',
    'content_id_column' => 'nid',
  );
  return $relationships;
}