<?php

/*
 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between
 * Copyright (C) 2006-2009 Dan Fuhry
 *
 * This program is Free Software; you can redistribute and/or modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for details.
 */

/**
 * Class that handles comments. Has HTML/Javascript frontend support.
 * @package Enano CMS
 * @subpackage Comment manager
 * @license GNU General Public License <http://www.gnu.org/licenses/gpl-2.0.html>
 */

class Comments
{
  #
  # VARIABLES
  #
  
  /**
   * Current list of comments.
   * @var array
   */
  
  var $comments = Array();
  
  /**
   * Object to track permissions.
   * @var object
   */
  
  var $perms;
  
  #
  # METHODS
  #
  
  /**
   * Constructor.
   * @param string Page ID of the page to load comments for
   * @param string Namespace of the page to load comments for
   */
  
  function __construct($page_id, $namespace)
  {
    global $db, $session, $paths, $template, $plugins; // Common objects
    
    // Initialize permissions
    if ( $page_id == $paths->page_id && $namespace == $paths->namespace )
      $this->perms =& $GLOBALS['session'];
    else
      $this->perms = $session->fetch_page_acl($page_id, $namespace);
    
    $this->page_id = $db->escape($page_id);
    $this->namespace = $db->escape($namespace);
  }
  
  /**
   * Processes a command in JSON format.
   * @param mixed Either the JSON-encoded input string, probably something sent from the Javascript/AJAX frontend, or an equivalent array
   */
   
  function process_json($json)
  {
    global $db, $session, $paths, $template, $plugins; // Common objects
    global $lang;
    
    $is_json = !is_array($json);
    
    if ( $is_json )
    {
      $data = enano_json_decode($json);
      $data = decode_unicode_array($data);
    }
    else
    {
      $data =& $json;
    }
    if ( !isset($data['mode']) )
    {
      $ret = Array('mode'=>'error','error'=>'No mode defined!');
      echo enano_json_encode($ret);
      return $ret;
    }
    if ( getConfig('enable_comments', '1') == '0' )
    {
      $ret = Array('mode'=>'error','error'=>'Comments are not enabled on this site.');
      echo enano_json_encode($ret);
      return $ret;
    }
    $ret = Array();
    $ret['mode'] = $data['mode'];
    switch ( $data['mode'] )
    {
      case 'fetch':
        if ( !$template->theme_loaded )
          $template->load_theme();
        if ( !isset($data['have_template']) )
        {
          $ret['template'] = file_get_contents(ENANO_ROOT . '/themes/' . $template->theme . '/comment.tpl');
        }
        $q = $db->sql_query('SELECT c.comment_id,c.name,c.subject,c.comment_data,c.time,c.approved,( c.ip_address IS NOT NULL ) AS have_ip,u.user_level,u.user_id,u.email,u.signature,u.user_has_avatar,u.avatar_type, b.buddy_id IS NOT NULL AS is_buddy, ( b.is_friend IS NOT NULL AND b.is_friend=1 ) AS is_friend FROM '.table_prefix.'comments AS c
                               LEFT JOIN '.table_prefix.'users AS u
                                 ON (u.user_id=c.user_id)
                               LEFT JOIN '.table_prefix.'buddies AS b
                                 ON ( ( b.user_id=' . $session->user_id.' AND b.buddy_user_id=c.user_id ) OR b.user_id IS NULL)
                               LEFT JOIN '.table_prefix.'ranks AS r
                                 ON ( ( u.user_rank = r.rank_id ) )
                               WHERE page_id=\'' . $this->page_id . '\'
                                 AND namespace=\'' . $this->namespace . '\'
                               GROUP BY c.comment_id,c.name,c.subject,c.comment_data,c.time,c.approved,c.ip_address,u.user_level,u.user_id,u.email,u.signature,u.user_has_avatar,u.avatar_type,b.buddy_id,b.is_friend
                               ORDER BY c.time ASC;');
        $count_appr = 0;
        $count_total = 0;
        $count_unappr = 0;
        $ret['comments'] = Array();
        if (!$q)
          $db->die_json();
        if ( $row = $db->fetchrow($q) )
        {
          do {
            
            // Increment counters
            $count_total++;
            ( $row['approved'] == 1 ) ? $count_appr++ : $count_unappr++;
            
            if ( !$this->perms->get_permissions('mod_comments') && $row['approved'] != COMMENT_APPROVED )
              continue;
            
            // Localize the rank
            $row = array_merge($row, $session->get_user_rank(intval($row['user_id'])));
            
            // Send the source
            $row['comment_source'] = $row['comment_data'];
            
            // Format text
            $row['comment_data'] = RenderMan::render($row['comment_data']);
            
            // Hide it if it's a post from a foe
            if ( $row['is_buddy'] == 1 && $row['is_friend'] == 0 )
            {
              $seed = md5(sha1(mt_rand() . microtime()));
              $wrapper = '
                <div id="posthide_'.$seed.'" style="display: none;">
                  ' . $row['comment_data'] . '
                </div>
                <p><span style="opacity: 0.4; filter: alpha(opacity=40);">' . $lang->get('comment_msg_foe_comment_hidden') . '</span> <span style="text-align: right;"><a href="#showpost" onclick="document.getElementById(\'posthide_'.$seed.'\').style.display=\'block\'; this.parentNode.parentNode.parentNode.removeChild(this.parentNode.parentNode); return false;">' . $lang->get('comment_btn_display_foe_comment') . '</a></span></p>
              ';
              $row['comment_data'] = $wrapper;
            }
            
            // Format date
            $row['time'] = enano_date(ED_DATE | ED_TIME, $row['time']);
            
            // Format signature
            $row['signature'] = ( !empty($row['signature']) ) ? RenderMan::render($row['signature']) : '';
            
            // Do we have the IP?
            $row['have_ip'] = ( $row['have_ip'] == 1 );
            
            // Avatar URL
            $row['avatar_path'] = make_avatar_url($row['user_id'], $row['avatar_type'], $row['email']);
            
            // Add the comment to the list
            $ret['comments'][] = $row;
            
          } while ( $row = $db->fetchrow($q) );
        }
        $db->free_result();
        $ret['count_appr'] = $count_appr;
        $ret['count_total'] = $count_total;
        $ret['count_unappr'] = $count_unappr;
        $ret['auth_mod_comments'] = $this->perms->get_permissions('mod_comments');
        $ret['auth_post_comments'] = $this->perms->get_permissions('post_comments');
        $ret['auth_edit_comments'] = $this->perms->get_permissions('edit_comments');
        $ret['auth_edit_wysiwyg'] = $this->perms->get_permissions('edit_wysiwyg');
        $ret['user_id'] = $session->user_id;
        $ret['username'] = $session->username;
        $ret['logged_in'] = $session->user_logged_in;
        
        $ret['user_level'] = Array();
        $ret['user_level']['guest'] = USER_LEVEL_GUEST;
        $ret['user_level']['member'] = USER_LEVEL_MEMBER;
        $ret['user_level']['mod'] = USER_LEVEL_MOD;
        $ret['user_level']['admin'] = USER_LEVEL_ADMIN;
        
        $ret['approval_needed'] = ( getConfig('approve_comments', '0') == '1' );
        $ret['guest_posting'] = getConfig('comments_need_login');
        
        if ( $ret['guest_posting'] == '1' && !$session->user_logged_in )
        {
          $session->kill_captcha();
          $ret['captcha'] = $session->make_captcha();
        }
        break;
      case 'edit':
        $cid = (string)$data['id'];
        if ( !ctype_digit($cid) || intval($cid) < 1 )
        {
          echo '{"mode":"error","error":"HACKING ATTEMPT"}';
          return false;
        }
        $cid = intval($cid);
        $q = $db->sql_query('SELECT c.user_id,c.approved FROM '.table_prefix.'comments c LEFT JOIN '.table_prefix.'users u ON (u.user_id=c.user_id) WHERE comment_id='.$cid.';');
        if(!$q)
          $db->die_json();
        $row = $db->fetchrow();
        $uid = intval($row['user_id']);
        $can_edit = ( ( $uid == $session->user_id && $uid != 1 && $this->perms->get_permissions('edit_comments') ) || ( $this->perms->get_permissions('mod_comments') ) );
        if(!$can_edit)
        {
          echo '{"mode":"error","error":"HACKING ATTEMPT"}';
          return false;
        }
        $data['data'] = str_replace("\r", '', $data['data']); // Windows compatibility
        $text = RenderMan::preprocess_text($data['data'], true, false);
        $text2 = $db->escape($text);
        $subj = $db->escape(htmlspecialchars($data['subj']));
        $q = $db->sql_query('UPDATE '.table_prefix.'comments SET subject=\'' . $subj . '\',comment_data=\'' . $text2 . '\' WHERE comment_id=' . $cid . ';');
        if(!$q)
          $db->die_json();
        $ret = Array(
            'mode' => 'redraw',
            'id'   => $data['local_id'],
            'subj' => htmlspecialchars($data['subj']),
            'text' => RenderMan::render($text),
            'src'  => $text,
            'approved' => $row['approved']
          );
        break;
      case 'delete':
        $cid = (string)$data['id'];
        if ( !ctype_digit($cid) || intval($cid) < 1 )
        {
          echo '{"mode":"error","error":"HACKING ATTEMPT"}';
          return false;
        }
        $cid = intval($cid);
        $q = $db->sql_query('SELECT c.user_id FROM '.table_prefix.'comments c LEFT JOIN '.table_prefix.'users u ON (u.user_id=c.user_id) WHERE comment_id='.$cid.';');
        if(!$q)
          $db->die_json();
        $row = $db->fetchrow();
        $uid = intval($row['user_id']);
        $can_edit = ( ( $uid == $session->user_id && $uid != 1 && $this->perms->get_permissions('edit_comments') ) || ( $this->perms->get_permissions('mod_comments') ) );
        if(!$can_edit)
        {
          echo '{"mode":"error","error":"HACKING ATTEMPT"}';
          return false;
        }
        $q = $db->sql_query('DELETE FROM '.table_prefix.'comments WHERE comment_id='.$cid.';');
        if(!$q)
          $db->die_json();
        $ret = Array(
            'mode' => 'annihilate',
            'id'   => $data['local_id']
          );
        break;
      case 'submit':
        
        // Now for a huge round of security checks...
        
        $errors = Array();
        
        // Authorization
        // Like the rest of the ACL system, this call is a one-stop check for ALL ACL entries.
        if ( !$this->perms->get_permissions('post_comments') )
          $errors[] = 'The site security policy prevents your user account from posting comments;';
        
        // Guest authorization
        if ( getConfig('comments_need_login') == '2' && !$session->user_logged_in )
          $errors[] = $lang->get('comment_err_need_login');
        
        // CAPTCHA code
        if ( getConfig('comments_need_login') == '1' && !$session->user_logged_in )
        {
          $real_code = $session->get_captcha($data['captcha_id']);
          if ( strtolower($real_code) !== strtolower($data['captcha_code']) )
            $errors[] = $lang->get('comment_err_captcha_wrong');
          $session->kill_captcha();
        }
        
        // Spam check
        $spam_policy = getConfig('comment_spam_policy', 'moderate');
        $sc_name = ( $session->user_logged_in ) ? $session->username : $data['name'];
        $sc_mail = ( $session->user_logged_in ) ? $session->email : false;
        $sc_url  = ( $session->user_logged_in ) ? @$session->user_extra['user_homepage'] : false;
        $spamcheck = $spam_policy === 'accept' ? true : spamalyze($data['text'], $sc_name, $sc_mail, $sc_url);
        if ( !$spamcheck && $spam_policy === 'reject' )
        {
          $errors[] = $lang->get('comment_err_spamcheck_failed_rejected');
        }
        
        if ( count($errors) > 0 )
        {
          $ret = Array(
            'mode' => 'error',
            'error' => implode("\n", $errors)
            );
        }
        else
        {
          // We're authorized!
          
          // Preprocess
          $name = ( $session->user_logged_in ) ? htmlspecialchars($session->username) : htmlspecialchars($data['name']);
          $subj = htmlspecialchars($data['subj']);
          $text = RenderMan::preprocess_text($data['text'], true, false);
          $src = $text;
          $sql_subj = $db->escape($subj);
          $sql_text = $db->escape($text);
          $text = RenderMan::render($text);
          $appr = ( getConfig('approve_comments', '0') == '1' ) ? COMMENT_UNAPPROVED : COMMENT_APPROVED;
          if ( $appr === COMMENT_APPROVED && $spam_policy === 'moderate' && !$spamcheck )
            $appr = COMMENT_SPAM;
          $time = time();
          $date = enano_date(ED_DATE | ED_TIME, $time);
          $ip = $_SERVER['REMOTE_ADDR'];
          if ( !is_valid_ip($ip) )
            die('Hacking attempt');
          
          // Send it to the database
          $q = $db->sql_query('INSERT INTO '.table_prefix.'comments(page_id,namespace,name,subject,comment_data,approved, time, user_id, ip_address) VALUES' . "\n  " .
                             "('$this->page_id', '$this->namespace', '$name', '$sql_subj', '$sql_text', $appr, $time, {$session->user_id}, '$ip');");
          if(!$q)
            $db->die_json();
          
          // Re-fetch
          $q = $db->sql_query('SELECT c.comment_id,c.name,c.subject,c.comment_data,c.time,c.approved,u.user_level,u.user_id,u.email,u.signature,u.user_has_avatar,u.avatar_type FROM '.table_prefix.'comments AS c
                               LEFT JOIN '.table_prefix.'users AS u
                                 ON (u.user_id=c.user_id)
                               WHERE page_id=\'' . $this->page_id . '\'
                                 AND namespace=\'' . $this->namespace . '\'
                                 AND time='.$time.' ORDER BY comment_id DESC LIMIT 1;');
          if(!$q)
            $db->die_json();
          
          $row = $db->fetchrow();
          $db->free_result();
          $row['time'] = $date;
          $row['comment_data'] = $text;
          $row['comment_source'] = $src;
          $ret = Array(
              'mode' => 'materialize'
            );
          $ret = enano_safe_array_merge($ret, $row);
          
          $ret['auth_mod_comments'] = $this->perms->get_permissions('mod_comments');
          $ret['auth_post_comments'] = $this->perms->get_permissions('post_comments');
          $ret['auth_edit_comments'] = $this->perms->get_permissions('edit_comments');
          $ret['user_id'] = $session->user_id;
          $ret['rank_data'] = $session->get_user_rank($session->user_id);
          $ret['username'] = $session->username;
          $ret['logged_in'] = $session->user_logged_in;
          $ret['signature'] = RenderMan::render($row['signature']);
          
          $ret['user_level_list'] = Array();
          $ret['user_level_list']['guest'] = USER_LEVEL_GUEST;
          $ret['user_level_list']['member'] = USER_LEVEL_MEMBER;
          $ret['user_level_list']['mod'] = USER_LEVEL_MOD;
          $ret['user_level_list']['admin'] = USER_LEVEL_ADMIN;
          $ret['avatar_path'] = make_avatar_url($row['user_id'], $row['avatar_type'], $row['email']);
        }
        
        break;
      case 'approve':
        if ( !$this->perms->get_permissions('mod_comments') )
        {
          $ret = Array(
          'mode' => 'error', 
          'error' => 'You are not authorized to moderate comments.'
          );
          echo enano_json_encode($ret);
          return $ret;
        }
        
        $cid = (string)$data['id'];
        if ( !ctype_digit($cid) || intval($cid) < 1 )
        {
          echo '{"mode":"error","error":"HACKING ATTEMPT"}';
          return false;
        }
        $cid = intval($cid);
        $q = $db->sql_query('SELECT subject,approved FROM '.table_prefix.'comments WHERE comment_id='.$cid.';');
        if(!$q || $db->numrows() < 1)
          $db->die_json();
        $row = $db->fetchrow();
        $db->free_result();
        $appr = ( $row['approved'] == '1' ) ? '0' : '1';
        $q = $db->sql_query('UPDATE '.table_prefix."comments SET approved=$appr WHERE comment_id=$cid;");
        if (!$q)
          $db->die_json();
        
        $ret = Array(
            'mode' => 'redraw',
            'approved' => $appr,
            'subj' => $row['subject'],
            'id'   => $data['local_id'],
            'approve_updated' => 'yes'
          );
        
        break;
      case 'view_ip':
        if ( !$session->get_permissions('mod_comments') )
        {
          return array(
              'mode' => 'error',
              'error' => 'Unauthorized'
            );
        }
        // fetch comment info
        if ( !is_int($data['id']) )
        {
          return array(
              'mode' => 'error',
              'error' => 'Unauthorized'
            );
        }
        $id =& $data['id'];
        $q = $db->sql_query('SELECT ip_address, name FROM ' . table_prefix . 'comments WHERE comment_id = ' . $id . ';');
        if ( !$q || $db->numrows() < 1 )
        {
          $db->die_json();
        }
        list($ip_addr, $name) = $db->fetchrow_num($q);
        $db->free_result();
        $name = $db->escape($name);
        $username = $db->escape($session->username);
        // log this action
        $q = $db->sql_query('INSERT INTO ' . table_prefix . "logs(time_id, log_type, action, page_text, author, edit_summary) VALUES\n  "
                            . "( " . time() . ", 'security', 'view_comment_ip', '$name', '$username', '{$_SERVER['REMOTE_ADDR']}' );");
        if ( !$q )
          $db->die_json();
        
        // send packet
        $ret = array(
            'mode' => 'redraw',
            'ip_addr' => $ip_addr,
            'local_id' => $data['local_id']
          );
        break;
      default:
        $ret = Array(
          'mode' => 'error', 
          'error' => $data['mode'] . ' is not a valid request mode'
          );
        break;
    }
    if ( $is_json )
      echo enano_json_encode($ret);
    
    return $ret;
  }
  
} // class Comments