<?php
// $Id: karma.module,v 1.35 2006/08/25 01:06:35 drumm Exp $

include './'. drupal_get_path('module', 'karma') .'/karma.theme';

function karma_help($page) {
  switch ($page) {
    case 'admin/modules#description':
      return t('Adds comment ratings with a karma system.');
  }
}

function karma_menu($may_cache) {
  $items = array();

  $items[] = array(
    'path' => 'admin/settings/karma',
    'title' => t('karma'),
    'callback' => 'drupal_get_form',
    'callback arguments' =>  array('karma_admin_settings'),
    'access' => user_access('administer comments'),
    'type' => MENU_NORMAL_ITEM,
    );
    
  if ($may_cache) {
    $items[] = array(
      'path' => 'karma',
      'title' => t('ratings'),
      'callback' => 'karma_ratings_page',
      'callback arguments' => array('karma_ratings_page'),
      'access' => user_access('access comments'),
      'type' => MENU_NORMAL_ITEM,
    );
    $items[] = array(
      'path' => 'karma/rate_js',
      'callback' => 'karma_rate_js',
      'access' => user_access('access comments'),
      'type' => MENU_CALLBACK,
    );
  }

  return $items;
}

function karma_admin_settings(){
 $form = array();

  $form['karma_minimum_rating'] = array(
    '#type' => 'select',
    '#title' => t('Minimum rating for displayed comments'),
    '#options' => array('0.0' => t('Show all comments')) + drupal_map_assoc(array('0.5', '1.0', '1.5', '2.0')),
    '#default_value' => variable_get('karma_minimum_rating', '0.0'),
    '#description' => t('Trusted users may choose to view comments with low ratings.'),
  );
  $form['karma_trusted_karma'] = array(
    '#type' => 'select',
    '#title' => t('Minimum rating for trusted users'),
    '#options' => drupal_map_assoc(array('2.5', '3.0', '3.5')),
    '#default_value' => variable_get('karma_trusted_karma', '3.5'),
    '#description' => t('Trusted users may view low-rated comments.'),
  );

  $karma_rating_titles = variable_get('karma_rating_titles', array());
  $form['karma_rating_titles'] = array(
    '#type' => 'fieldset',
    '#title' => t('Rating titles'),
    '#tree' => TRUE,
  );
  foreach (range(0, 5) as $rating) {
    $form['karma_rating_titles'][$rating] = array(
      '#type' => 'textfield',
      '#title' => t('Title for %rating', array('%rating' => $rating)),
      '#default_value' => $karma_rating_titles[$rating],
    );
  }

  $form['karma_selector_type'] = array(
    '#type' => 'radios',
    '#title' => t('Selector type'),
    '#options' => array('select' => t('Drop down selection'), 'stars' => t('Stars')),
    '#default_value' => variable_get('karma_selector_type', 'select'),
  );

  $form['karma_merge_widgets'] = array(
    '#type' => 'radios',
    '#title' => t('Rating widget display'),
    '#options' => array(
      'normal' => t('Separate average rating and rating selection'),
      'merged' => t('Show average rating on rating selection'),
    ),
    '#default_value' => variable_get('karma_merge_widgets', 'normal'),
  );
  if (variable_get('karma_selector_type', 'select') == 'select') {
    $form['karma_merge_widgets']['#attributes'] = array('disabled' => 'disabled');
    }

  return system_settings_form($form);
} 

function karma_perm() {
  return array('rate comments', 'rate posts', 'user is always trusted', 'view user ratings', 'view comment ratings', 'view post ratings');
}

/**
 * Determine if the current user is trusted. Trusted users have a karma above a
 * configurable threshold.
 *
 * @return
 *   TRUE if the current user is trusted.
 */
function karma_user_is_trusted() {
  global $user;

  if (user_access('user is always trusted')) {
    return TRUE;
  }
  
  karma_user_load($user);

  if (!is_null($user->karma)) {
    return $user->karma >= variable_get('karma_trusted_karma', '3.5');
  }

  return FALSE;
}

/**
 * Loads the user's karma rating. If karma is already added it will not be loaded again.
 *
 * @param $user
 *   The user object to add karma to.
 */
function karma_user_load(&$user) {
  if (!isset($user->karma)) {
    $karma = db_fetch_object(db_query('SELECT karma FROM {karma_users} WHERE uid = %d', $user->uid));
    $user->karma = (float) $karma->karma;
  }
}

/**
 * Returns the current user's rating for a comment or post.
 *
 * @param $type
 *   Either 'comment' or 'node'
 * @param $object
 *   A comment or node object.
 * @return
 *   An integer or, if the user hasn't rated the comment, NULL.
 */
function karma_get_user_rating($type, $object) {
  global $user;
  static $ratings = array(
    'comment' => array(),
    'node' => array(),
  );
  $id = ($type == 'comment' ? $object->cid : $object->nid);

  if (!isset($ratings[$type][$object->nid])) {
    $ratings[$type][$object->nid] = array();
    switch ($type) {
      case 'comment':
        $result = db_query("SELECT r.id, r.rating FROM {karma_ratings} r LEFT JOIN {comments} c ON r.id = c.cid WHERE r.uid = %d AND c.nid = %d AND r.type = 'cid'", $user->uid, $object->nid);
        break;

      case 'node':
        $result = db_query("SELECT r.id, r.rating FROM {karma_ratings} r WHERE r.uid = %d AND r.id = %d AND r.type = 'nid'", $user->uid, $object->nid);
        break;
    }
    while ($rating = db_fetch_object($result)) {
      $ratings[$type][$object->nid][$rating->id] = $rating->rating;
    }
  }

  return $ratings[$type][$object->nid][$id];
}

/**
 * Returns information about a comment's or post's rating.
 *
 * @param $type
 *   Either 'comment' or 'node'
 * @param $object
 *   A comment object.
 * @param $clear
 *   TRUE to clear the internal cache.
 * @return
 *   A numerically indexed (for use with list()) array containing the comment
 *   rating and the number of users who have rated the comment.
 */
function karma_get_rating($type, $object, $clear = FALSE) {
  static $ratings = array(
    'comment' => array(),
    'node' => array(),
  );

  if ($clear) {
    $ratings = array(
      'comment' => array(),
      'node' => array(),
    );
  }

  if (!isset($ratings[$type][$object->nid])) {
    $ratings[$type][$object->nid] = array();
    switch ($type) {
      case 'comment':
        $result = db_query("SELECT k.id, k.rating, k.count FROM {karma_objects} k LEFT JOIN {comments} c ON k.id = c.cid WHERE c.nid = %d AND k.type = 'cid'", $object->nid);
        break;

      case 'node':
        $result = db_query("SELECT k.id, k.rating, k.count FROM {karma_objects} k WHERE k.id = %d AND k.type = 'nid'", $object->nid);
        break;
    }
    while ($rating = db_fetch_object($result)) {
      $ratings[$type][$object->nid][$type == 'comment' ? $rating->id : 'node'] = array($rating->rating, $rating->count);
    }
  }

  return $ratings[$type][$object->nid][$type == 'comment' ? $object->cid : 'node'];
}

/**
 * Updates a user's karma rating.
 *
 * The karma calculation is a weighted average of individual comment ratings.
 * The weight is the number of ratings a comment has recieved multiplied by the
 * comment number (oldest comment is numbered 1).
 *
 * @param $uid
 *   The user's uid.
 */
function karma_update_user_karma($uid) {
  if (!$uid) {
    // The anonymous user does not have karma.
    return;
  }

  $ratings = db_query_range("SELECT k.rating, k.count, GREATEST(c.timestamp, n.created) AS timestamp FROM {karma_objects} k LEFT JOIN {comments} c ON k.type = 'cid' AND k.id = c.cid AND c.uid = %d LEFT JOIN {node} n ON k.type = 'nid' AND k.id = n.nid AND n.uid = %d ORDER BY timestamp DESC, k.rating", $uid, $uid, 0, 30);
  $comment_num = 1;
  $sum = 0;
  $count = 0;
  while ($rating = db_fetch_object($ratings)) {
    $sum += $rating->rating * ($rating->count * $comment_num);
    $count += $rating->count * $comment_num;
    $comment_num++;
  }

  if ($count == 0) {
    // Users without any rated comments do not have karma.
    $karma = NULL;
  }
  else {
    $karma = $sum / $count;
  }

  // First delete any existing entry, then add the new entry
  db_query('DELETE FROM {karma_users} WHERE uid = %d', $uid);
  db_query('INSERT INTO {karma_users} (uid, karma) VALUES (%d, %f)', $uid, $karma);
}

function karma_comment(&$comment, $op) {
  if ($op == 'view' && arg(1) != 'reply' && user_access('view comment ratings')) {
    $rating_form = _karma_rating('comment', $comment);
    theme('add_style', drupal_get_path('module', 'karma') .'/karma.css');
    drupal_add_js(drupal_get_path('module', 'karma') .'/karma.js');

    // Display current rating.
    list($rating, $count) = karma_get_rating('comment', $comment);
    if (variable_get('karma_selector_type', 'select') == 'stars') {
      $comment = theme('karma_comment_rating_stars', $comment, (float) $rating, $count, 'karma/comment/'. $comment->cid, $rating_form);
    }
    else {
      $comment = theme('karma_comment_rating', $comment, (float) $rating, $count, 'karma/comment/'. $comment->cid, $rating_form);
    }
  }
}

function karma_nodeapi(&$node, $op, $teaser = NULL, $page = NULL) {
  switch ($op) {
    case 'view':
      if (user_access('view post ratings') && variable_get('karma_enabled_'. $node->type, TRUE)) {
        $rating_form = _karma_rating('node', $node);
        theme('add_style', drupal_get_path('module', 'karma') .'/karma.css');
        drupal_add_js(drupal_get_path('module', 'karma') .'/karma.js');

        // Display current rating.
        list($rating, $count) = karma_get_rating('node', $node);
        if (variable_get('karma_selector_type', 'select') == 'stars') {
          $node = theme('karma_node_rating_stars', $node, (float) $rating, $count, 'karma/node/'. $node->nid, $rating_form);
        }
        else {
          $node = theme('karma_node_rating', $node, (float) $rating, $count, 'karma/node/'. $node->nid, $rating_form);
        }
      }
      break;
  }
}

function karma_rate_validate($form_id, $form_values) {
  global $user;

  if (!is_numeric($form_values['rating']) || $form_values['rating'] > 5 || $form_values['rating'] < -1) {
    form_set_error('rating', t('Invalid rating.'));
  }
  if ($form_values['rating'] == 0 && !karma_user_is_trusted()) {
    form_set_error('rating', t('Only trusted users may give a 0 rating.'));
  }
}

function _karma_rating_form_submit($form_id, $form_values) {
  global $user;
  $type = 'comment';
  switch ($form_values['type']) {
    case 'comment':
      $id_type = 'cid';
      break;

    case 'node':
      $id_type = 'nid';
      break;
  }

  // Remove any existing rating and insert the new rating
  db_query("DELETE FROM {karma_ratings} WHERE uid = %d AND id = %d AND type = '%s'", $user->uid, $form_values['id'], $id_type);
  if ($form_values['rating'] != -1) {
    // -1 is not rated
    db_query("INSERT INTO {karma_ratings} (uid, id, type, rating) VALUES (%d, %d, '%s', %d)", $user->uid, $form_values['id'], $id_type, $form_values['rating']);
  }

  // Update the comment rating
  db_query("DELETE FROM {karma_objects} WHERE id = %d AND type = '%s'", $form_values['id'], $id_type);
  db_query("INSERT INTO {karma_objects} (id, type, rating, count) SELECT id, '%s', avg(rating), count(uid) FROM {karma_ratings} WHERE id = %d AND type = '%s' GROUP BY id", $id_type, $form_values['id'], $id_type);
 
 if ($id_type = 'cid') {

   }
 
  // Update the comment owner's karma
  switch ($form_values['type']) {
    case 'comment':
      $object = db_fetch_object(db_query('SELECT uid FROM {comments} WHERE cid = %d', $form_values['id']));
      break;

    case 'node':
      $object = db_fetch_object(db_query('SELECT uid FROM {node} WHERE nid = %d', $form_values['id']));
      break;
  }
  karma_update_user_karma($object->uid);

  // todo ??
  //drupal_goto('node/'. $comment->nid, NULL, 'comment-'. $comment->cid);
  return FALSE;
}

function karma_rate_js($type, $id) {
  switch ($type) {
    case 'comment':
      $object = _comment_load($id);
      break;

    case 'node':
      $object = node_load($id);
      break;
  }
  _karma_rating($type, $object);
  list($rating, $count) = karma_get_rating($type, $object, TRUE);

  if (variable_get('karma_selector_type', 'select') == 'stars') {
    $rating_text = theme('karma_comment_rating_stars_content', (float) $rating, $count, 'karma/'. $type .'/'. $id);
  }
  else {
    $rating_text = theme('karma_comment_rating_text', (float) $rating, $count, 'karma/'. $type .'/'. $id);
  }

  switch (variable_get('karma_merge_widgets', 'normal')) {
    case 'normal':
      $current_rating = karma_get_user_rating($type, $object);
      break;

    case 'merged':
      $current_rating = $rating;
      break;
  }

  print drupal_to_js(array('status' => TRUE, 'data' => $rating_text, 'current_rating' => $current_rating));
  exit;
}

function _karma_rating($type, $object) {
switch ($type) {
    case 'comment':
      if (!user_access('rate comments')) {
        return NULL;
      }
      $id = $object->cid;
      break;

    case 'node':
      if (!user_access('rate posts')) {
        return NULL;
      }
      $id = $object->nid;
      break;
  }
  
  $output = drupal_get_form('_karma_rating_form'. '_'. $type .'_'. $id, $type, $object, $id);
  return $output;
  }
  
function _karma_rating_form($type, $object) {
  global $user;
  switch ($type) {
    case 'comment':
      if (!user_access('rate comments')) {
        return NULL;
      }
      $id = $object->cid;
      break;

    case 'node':
      if (!user_access('rate posts')) {
        return NULL;
      }
      $id = $object->nid;
      break;
  }

  // Rating form. The user must be logged in, have permission to rate
  // comments, and not be the author of the comment.
  if (isset($user->uid) && $object->uid != $user->uid) {
    $form = array('#attributes' => array('class' => 'karma-rate-comment'));
    $rating_options = array(-1 => t('Not rated'));
    $rating_titles = variable_get('karma_rating_titles', array());
    foreach (range(karma_user_is_trusted() ? 0 : 1, 4) as $rating) {
      if (isset($rating_titles[$rating]) && strlen($rating_titles[$rating]) > 0) {
        $rating_options[$rating] = $rating .': '. $rating_titles[$rating];
      }
      else {
        $rating_options[$rating] = $rating;
      }
    }
    $form['rating'] = array(
      '#type' => 'select',
      '#options' => $rating_options,
      '#default_value' => karma_get_user_rating($type, $object),
      '#id' => 'edit-rating-'. $type .'-'. $id,
      '#attributes' => array('class' => 'karma-rating-select'),
    );
    if (!is_null(karma_get_user_rating($type, $object))) {
      switch ($type) {
        case 'comment':
          $form['rating']['#description'] = t('You have already rated this comment. Selecting a new rating will replace your old rating.');
          break;

        case 'node':
          $form['rating']['#description'] = t('You have already rated this post. Selecting a new rating will replace your old rating.');
          break;
      }
    }
    else {
      $form['rating']['#default_value'] = -1;
    }

    // Stars, if enabled.
    if (variable_get('karma_selector_type', 'select') == 'stars') {
      $form['rating']['#attributes']['class'] .= ' has-stars';
      switch ($type) {
        case 'comment':
          $output = '<strong class="karma-stars-label">'. t('Rate this comment') .'</strong>';
          break;

        case 'node':
          $output = '<strong class="karma-stars-label">'. t('Rate this post') .'</strong>';
          break;
      }
      if (karma_user_is_trusted()) {
        $output .= '<a id="karma-stars-zero-'. $type .'-'. $id .'" class="karma-stars-zero'. (karma_get_user_rating($type, $object) === 0 ? ' karma-stars-zero-selected' : '') .'" onclick="karmaSelectRating(\''. $type .'\', '. $id .', 0)"> </a>';
      }
      $output .= '<ul id="karma-stars-'. $type .'-'. $id .'" class="karma-stars'. (karma_user_is_trusted() ? ' karma-user-is-trusted' : '') .'">';
      switch (variable_get('karma_merge_widgets', 'normal')) {
        case 'normal':
          $current_rating = karma_get_user_rating($type, $object);
          break;

        case 'merged':
          list($current_rating, $dummy) = karma_get_rating($type, $object);
          break;
      }
      $output .= '<li id="current-rating-'. $type .'-'. $id .'" class="current-rating" style="width: '. $current_rating * 17 .'px;"> </li>';
      foreach (range(1, 4) as $rating) {
        $output .= '<li><a class="rating-'. $rating .'" onclick="karmaSelectRating(\''. $type .'\', '. $id .', '. $rating .')"'. (isset($rating_titles[$rating]) ? ' title="'. $rating_titles[$rating] .'"'  : '') .'> </a></li>';
      }
      $output .= '</ul>';
      $output .= '<a id="karma-not-rated-'. $type .'-'. $id .'" class="karma-not-rated'. (karma_get_user_rating($type, $object) === NULL ? ' karma-not-rated-selected' : '') .'" onclick="karmaSelectRating(\''. $type .'\', '. $id .', -1)">'. t('Not rated') .'</a>';
      $form['rating']['#prefix'] = $output;
    }
    
    $form['rating-uri'] = array(
      '#type' => 'hidden',
      '#value' => url('karma/rate_js/'. $type .'/'. $id, NULL, NULL, TRUE),
      '#id' => 'uri-rating-'. $type .'-'. $id,
    );
    $form['op'] = array(
      '#type' => 'submit',
      '#value' => t('Rate'),
    );
    $form['id'] = array(
      '#type' => 'value',
      '#value' => $id,
    );
    $form['type'] = array(
      '#type' => 'value',
      '#value' => $type,
    );
    
    $form['#base'] = '_karma_rating_form';
    
    return $form;
  }
  else {
    return NULL;
  }
}

function karma_user($op, &$edit, &$user, $category = NULL) {
  switch ($op) {
    case 'view':
      if (!is_null($user->karma) && user_access('view user ratings')) {
        return array(t('Karma') => array(array('value' => round($user->karma, 2))));
      }
      break;

    case 'load':
      karma_user_load($user);
      break;

    case 'delete':
      db_query('DELETE FROM {karma_users} WHERE uid = %d', $user->uid);
      break;

    case 'insert':
    case 'update': // intended fall-through
      // Don't save karma in $data
      $user->karma = NULL;
      break;
  }
}

function karma_form_alter($form_id, &$form) {
  global $user;
  if ($form_id == 'comment_controls' && karma_user_is_trusted()) {
    $form['karma_show'] = array(
      '#type' => 'select',
      '#default_value' => (isset($user->karma_show) ? $user->karma_show : TRUE),
      '#options' => array(TRUE => t('Show low-rated comments'), FALSE => t('Hide low-rated comments')),
      '#weight' => 5,
    );
    $form['#execute'][] = 'karma_comment_controls_submit';
  }

  if (isset($form['type'])) {
    // Node settings
    if ($form['type']['#value'] .'_node_settings' == $form_id) {
      $form['workflow']['karma_enabled_'. $form['type']['#value']] = array(
        '#type' => 'checkbox',
        '#title' => t('Enable karma ratings'),
        '#default_value' => variable_get('karma_enabled_'. $form['type']['#value'], TRUE),
      );
    }
  }
}

function karma_comment_controls_submit($form_id, $form_values) {
  global $user;

  // We can assume that a user is loaded since they have enough karma to be
  // trusted.
  $user = user_save($user, array('karma_show' => $form_values['karma_show']));

  // The user object has already been used at this point and we need to restart
  // the page generation.
  drupal_goto($_GET['q'], NULL, 'comment');
}

function karma_db_rewrite_sql($query, $primary_table, $primary_field, $args) {
  global $user;

  if ($primary_table == 'c' && !(karma_user_is_trusted() && (isset($user->karma_show) ? $user->karma_show : TRUE))) {
    $min = (float) variable_get('karma_minimum_rating', '0.0');
    return array(
      'join' => "LEFT JOIN {karma_objects} ko ON ko.id = c.cid AND ko.type = 'cid' LEFT JOIN {karma_users} ku ON ku.uid = c.uid",
      'where' => 'ko.rating >= '. $min .' OR (ko.rating IS NULL AND (ku.karma >= '. $min .' OR ku.karma IS NULL)) OR c.uid = '. (int) $user->uid,
    );
  }
}

function karma_ratings_page($type, $id) {
  switch ($type) {
    case 'comment':
      $object = db_fetch_object(db_query('SELECT n.nid, c.cid, c.subject, n.title AS node_title FROM {comments} c LEFT JOIN {node} n ON c.nid = n.nid WHERE c.cid = %d', $id));
      break;

    case 'node':
      $object = db_fetch_object(db_query('SELECT nid, title AS subject, title AS node_title FROM {node} WHERE nid = %d', $id));
      break;
  }

  menu_set_location(array(
    array('path' => 'node/'. $object->nid, 'title' => $object->node_title),
    array('path' => 'karma/'. $type .'/'. $id, 'title' => t('Ratings for: "%subject" ', array('%subject' => $object->subject))),
  ));

  $ratings = db_query("SELECT r.rating, u.uid, u.name FROM {karma_ratings} r LEFT JOIN {users} u ON r.uid = u.uid WHERE r.id = %d AND r.type = '%s'", $id, ($type == 'comment' ? 'cid' : 'nid'));
  $rows = array();
  $rating_sum = 0;
  while ($rating = db_fetch_object($ratings)) {
    $rows[] = array(l($rating->name, 'user/'. $rating->uid), $rating->rating);
    $rating_sum += $rating->rating;
  }
  $header = array(t('User'), t('Rating'));
  $output = theme('table', $header, $rows);

  if (db_num_rows($ratings) > 0) {
    $output .= '<p id="karma-average">'. t('Average rating: %average', array('%average' => $rating_sum / db_num_rows($ratings))) .'</p>';
  }
  else {
    $output .= '<p id="karma-average">'. t('No ratings.') . '</p>';
  }

  switch ($type) {
    case 'comment':
//      $output .= theme('links', array(l(t('Back to %title', array('%title' => theme('placeholder', $object->node_title))), 'node/'. $object->nid, array(), NULL, 'comment-'. $object->cid, FALSE, TRUE)));
      break;

    case 'node':
      //$output .= theme('links', array(l(t('Back to %title', array('%title' => theme('placeholder', $object->node_title))), 'node/'. $object->nid, array(), NULL, NULL, FALSE, TRUE)));
      break;
  }

  return $output;
}

function karma_forms($args)  {
  list($form_id, $type, $object, $id) = $args;
  $forms['_karma_rating_form_'. $type .'_'. $id] = array('callback' => '_karma_rating_form', $type, $object);
  return $forms;
}