<?php
// $Id: revision_moderation.module,v 1.49.2.1 2009-10-18 20:19:52 brauerranch Exp $

/**
 * @file
 * Allows moderation of node revisions while existing revisions stay visible.
 */

// Actions module support.
include_once drupal_get_path('module', 'revision_moderation') . '/revision_moderation_actions.inc';

/**
 * Implement hook_menu().
 */
function revision_moderation_menu() {
  $items = array();

  // Admin menu
  $items['admin/content/node/revisions'] = array(
    'title' => 'Pending revisions',
    'page callback' => 'revision_moderation_pending_revisions_admin',
    'access arguments' => array('administer nodes'),
    'type' => MENU_LOCAL_TASK,
  );

  // Admin menu
  $items['admin/config/content/revision_moderation'] = array(
    'title' => 'Revision moderation',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('revision_moderation_settings'),
    'description' => 'Configure revision publishing options.',
    'access arguments' => array('administer nodes'),
  );

  // Callback to allow users to edit revisions.
  $items['node/%node/revisions/%/edit'] = array(
    'title' => 'Edit revision',
    'load arguments' => array(3),
    'page callback' => 'revision_moderation_edit',
    'page arguments' => array(1),
    'access callback' => '_node_revision_access',
    'access arguments' => array(1, 'update'),
    'file' => 'node.pages.inc',
    'file path' => drupal_get_path('module', 'node'),
    'type' => MENU_CALLBACK,
  );

  // Callback to allow users to publish revisions directly.
  $items['node/%node/revisions/%/publish'] = array(
    'title' => 'Publish revision',
    'load arguments' => array(3),
    'page callback' => 'drupal_get_form',
    'page arguments' => array('revision_moderation_publish_confirm', 1),
    'access callback' => '_node_revision_access',
    'access arguments' => array(1, 'update'),
    'type' => MENU_CALLBACK,
  );

  return $items;
}

/**
 * Menu permission callback.
 */
function revision_moderation_admin_permisson($nid) {
  $node = node_load($nid);
  $access = user_access('administer nodes') || (user_access('view revisions') && node_access('update', $node));
  return $access;
}

/**
 * Menu callback; admin settings page.
 */
function revision_moderation_settings() {
  $form['revision_moderation_exempt'] = array(
    '#type' => 'checkbox',
    '#title' => t('Exempt administrators from revision moderation'),
    '#default_value' => variable_get('revision_moderation_exempt', 1),
    '#description' => t('With this option enabled, users with the "administer nodes" privilege will bypass the moderation system, and their revisions will be published immediately.'),
  );

  return system_settings_form($form);
}

/**
 * Implement hook_form_alter().
 */
function revision_moderation_form_alter(&$form, $form_state, $form_id) {
  // On node edit forms, add in the "New revisions in moderation" option.
  if (!empty($form['#node_edit_form'])) {
    $default_value = in_array('revision_moderation', variable_get("node_options_{$form['type']['#value']}", array('status', 'promote')));
    if ($form['nid']['#value']) {
      $result = db_query_range('SELECT revision_moderation FROM {revision_moderation} WHERE nid = :nid', 0, 1, array(':nid' => $form['nid']['#value'], ))->fetchField();
      if ($result !== FALSE) {
        $default_value = $result;
      }
    }
    // Only show the checkbox if user has 'administer nodes' privileges.
    if (!empty($node->revision) || user_access('administer nodes')) {
      $form['revision_information']['revision_moderation'] = array(
        '#type' => 'checkbox',
        '#title' => t('New revisions in moderation'),
        '#default_value' => $default_value,
      );
    }
    else {
      $form['revision_moderation'] = array(
        '#type' => 'value',
        '#value' => $default_value,
      );
    }
  }
  // Also add option to node settings form
  elseif ($form_id == 'node_type_form') {
    $form['workflow']['node_options']['#options']['revision_moderation'] = t('New revisions in moderation');
  }
}

/**
 * Implement hook_node_insert().
 */
function revision_moderation_node_insert($node) {
  // Store revision moderation setting of this node.
  drupal_write_record('revision_moderation', $node);
}

/**
 * Implement hook_node_update().
 */
function revision_moderation_node_update($node) {
  // Update revision moderation setting of this node.
  drupal_write_record('revision_moderation', $node, 'nid');
  if ($node->nid && $node->revision_moderation == 1 && arg(2) != 'revisions'
    && (!user_access('administer nodes') || !variable_get('revision_moderation_exempt', 1))) {
    if (isset($node->original_node)) {
      // Update node table's vid to the original value.
      db_update('node')
        -> fields(array('vid'       => $node->original_node->vid,
                        'title'     => $node->original_node->title['zxx'][0]['value'],
                        'status'    => $node->original_node->status,
                        'moderate'  => $node->original_node->moderate,
                        ))
        ->condition('nid', $node->nid)
        ->execute();
      drupal_set_message(t('Your changes have been submitted for moderation.'));
    }
  }
}

/**
 * Implement hook_node_delete().
 */
function revision_moderation_node_delete($node) {
  // Delete record from revision_moderation table when node is deleted.
  db_delete('revision_moderation')
    ->condition('nid', $node->nid)
    ->execute();
}

/**
 * Implement hook_node_load().
 */
function revision_moderation_node_load($nodes, $types) {
   // Set a revision_moderation property which can be checked later.
  $results = db_query('SELECT revision_moderation, nid FROM {revision_moderation} WHERE nid IN(:nids)', array(':nids' => array_keys($nodes), ));
  foreach ($results as $record) {
    $nodes[$record->nid]->revision_moderation = $record->revision_moderation;
  }
}

/**
 * Implement hook_node_view().
 */
function revision_moderation_node_view($node) {
  // Cannot use _node_revision_access() here, it's static cached with 1 op
  $access_update = user_access('revert revisions');
  $access_delete = user_access('delete revisions');
  // Display more descriptive message at the top of node revision views, including operations
  // that the current user has available to them.
  $current_vid = db_query_range('SELECT vid FROM {node} WHERE nid = :nid', 0, 1,  array(':nid' => $node->nid, ))->fetchField();
  if ($node->vid != $current_vid) {
    $links = array(); // Array of links to show along with the message.
    if ($access_update) {
      // Add a link directly to the diff if we have Diff module installed.
      if (module_exists('diff')) {
        if ($node->vid > $current_vid) {
          $difflink = "node/$node->nid/revisions/view/$current_vid/$node->vid";
        }
        else {
          $difflink = "node/$node->nid/revisions/view/$node->vid/$current_vid";
        }
        $links[] = l(t('Compare revisions'), $difflink);
      }
      $links[] = l(t('Edit revision'), "node/$node->nid/revisions/$node->vid/edit");
      // If this revision is old, show an option to revert to it.
      // Otherwise, show an option to publish it.
      if ($node->vid < $current_vid) {
        $links[] = l(t('Revert to revision'), "node/$node->nid/revisions/$node->vid/revert");
      }
      else {
        $links[] = l(t('Publish revision'), "node/$node->nid/revisions/$node->vid/publish");
      }
    }
    if ($access_delete) {
      $links[] = l(t('Delete revision'), "node/$node->nid/revisions/$node->vid/delete");
    }
    // Get username for the revision rather than the original node.
    $author = user_load($node->revision_uid);
    $revision_author = array('account' => $author,
                             'name' => check_plain($author->name),
                             );
    drupal_set_message(t('You are currently viewing a revision of this post created on @date by !author.', array('@date' => format_date($node->revision_timestamp, 'small'), '!author' => theme('username', $revision_author))) . theme('item_list', $links));
  }
  elseif (isset($node->revision_moderation) && $node->revision_moderation == 1 && $node->build_mode != 'teaser') {
    // Notify admin if a node has pending revisions.
    if ($access_update && arg(2) != 'revisions' && revision_moderation_get_node_pending_revisions($node->nid)) {
      drupal_set_message(t('This post has one or more pending revisions: <a href="@list">view list of revisions</a>.', array('@list' => url("node/$node->nid/revisions"))));
    }
  }
}

/**
 * Implement hook_node_prepare().
 */
function revision_moderation_node_prepare($node) {
  if (isset($node->nid)) {
    if (isset($node->revision_moderation) && $node->nid && $node->revision_moderation == 1 && arg(2) != 'revisions'
      && (!user_access('administer nodes') || !variable_get('revision_moderation_exempt', 1))) {
      // If user has a pending revision for this node, load the latest version of
      // it instead.
      if ($revisions = revision_moderation_get_node_pending_revisions($node->nid)) {
        global $user;
        foreach ($revisions as $revision) {
          if ($revision->uid == $user->uid) {
            drupal_set_message(t('Editing your latest revision, which is still pending moderation.'));
            $node = node_load($node->nid, $revision->vid);
          }
        }
      }
    }
  }
}

/**
 * Implement hook_node_presave().
 */
function revision_moderation_node_presave($node) {
  if ($node->nid && $node->revision_moderation == 1 && arg(2) != 'revisions'
    && (!user_access('administer nodes') || !variable_get('revision_moderation_exempt', 1))) {
    $current_vid = db_query_range('SELECT vid FROM {node} WHERE nid = :nid', 0, 1, array(':nid' => $node->nid, ))->fetchField();
    $node->original_node = node_load($node->nid, $current_vid);
  }
}


/**
 * Implement hook_block().
 */
function revision_moderation_block($op = 'list', $delta = 0, $edit = array()) {
  if ($op == 'list') {
    $blocks[0]['info'] = t('Pending revisions');

    return $blocks;
  }
  elseif ($op == 'view') {
    $block = array();

    if (user_access('administer nodes')) {
      $output = '';
      $list = array();

      $nodes = revision_moderation_get_all_pending_revisions(10);
      if (count($nodes)) {
        foreach ($nodes as $node) {
          $list[] = l($node->title, "node/$node->nid/revisions/$node->vid/view");
        }
        $output .= theme('item_list', $list);
        $output .= '<p>' . l(t('View all pending revisions'), 'admin/content/node/revisions') . '</p>';
      }
      else {
        $output .= t('No pending revisions found.');
      }

      $block['subject'] = t('Pending revisions');
      $block['content'] = $output;
    }

    return $block;
  }
}

/**
 * Menu callback to display list of nodes with pending revisions.
 */
function revision_moderation_pending_revisions_admin() {
  return theme('revision_moderation_pending_revisions_admin');
}

/**
 * Implement hook_theme().
 */
function revision_moderation_theme() {
  return array(
    'revision_moderation_pending_revisions_admin' => array(
      'arguments' => array(),
    ),
  );
}

/**
 * Displays list of nodes with pending revisions.
 */
function theme_revision_moderation_pending_revisions_admin() {
  $nodes = revision_moderation_get_all_pending_revisions(50);
  if (count($nodes)) {
    $header = array(
      t('Title', array(), array('context' => 'Node title', )),
      t('Type', array(), array('context' => 'Node types', )),
      t('Updated by'),
      t('Last updated'),
    );
    $rows = array();
    foreach ($nodes as $node) {
      $rows[] = array(
        l($node->title['zxx'][0]['value'], "node/$node->nid/revisions"), 
        check_plain(node_get_type_name($node)),
        theme('username', user_load(array('uid' => $node->uid))),
        format_date($node->timestamp),
      );
    }
    return theme('table', array('header' => $header, 'rows' => $rows));
  }
  else {
    return '<p>' . t('No pending revisions found.') . '</p>';
  }
}

/**
 * Retrieve list of all pending revisions.
 *
 * @param $limit
 *  The number of pending revisions to retrieve.
 */
function revision_moderation_get_all_pending_revisions($limit) {
  // Obtain a list of nodes with revisions higher than current published revision.
  $sql = "SELECT n.nid, r.vid, n.type, r.title, r.body, r.uid, r.timestamp FROM {node} n INNER JOIN {node_revisions} r ON n.nid = r.nid WHERE r.vid > n.vid ORDER BY r.vid DESC LIMIT :limit";
  $result = db_query($sql, array(':limit' => $limit, ));
  $revisions = array();
  foreach ($result as $revision) {
    $revisions[$revision->nid] = $revision;
  }

  return $revisions;
}

/**
 * Retrieve list of all pending revisions for a given node.
 *
 * @param $nid
 *  The node ID to retrieve.
 */
function revision_moderation_get_node_pending_revisions($nid) {
  // Obtain a list of revisions higher than current published revision for a given node.
  $sql = "SELECT n.nid, r.vid, r.uid FROM {node} n INNER JOIN {node_revisions} r ON n.nid = r.nid WHERE r.vid > n.vid AND n.nid = :nid ORDER BY r.vid DESC";
  $result = db_query($sql, array(':nid' => $nid, ));
  $revisions = array();
  while ($revision = db_fetch_object($result)) {
    $revisions[$revision->vid] = $revision;
  }

  return $revisions;
}

/**
 * Menu callback; edit revision.
 */
function revision_moderation_edit($node) {
  // Get username for the revision rather than the original node.
  $revision_author = user_load($node->revision_uid);
  drupal_set_message(t('You are currently editing a revision of this post created on @date by !author.', array('@date' => format_date($node->revision_timestamp, 'small'), '!author' => theme('username', $revision_author))));
  return drupal_get_form($node->type . '_node_form', $node);
}

/**
 * Returns a confirmation page for publishing a revision.
 *
 * @param $node
 *   The node object for which revision is to be published.
 */
function revision_moderation_publish_confirm($form_state, $node) {
  $form['node_id'] = array('#type' => 'value', '#value' => $node->nid);
  $form['title'] = array('#type' => 'value', '#value' => $node->title);
  $form['revision'] = array('#type' => 'value', '#value' => $node->vid);
  $form['type'] = array('#type' => 'value', '#value' => $node->type);

  return confirm_form($form, t('Are you sure you want to publish this revision for %title?', array('%title' => $node->title)), 'node/' . $node->nid . '/revisions/' . $node->vid, t('Publishing this revision will make it public for all users.'), t('Publish'), t('Cancel'));
}

/**
 * Submission handler for the publish confirm form.
 * Publishes a revision directly.
 */
function revision_moderation_publish_confirm_submit($form, &$form_state) {
  $nid = $form_state['values']['node_id'];
  $title = $form_state['values']['title'];
  $vid = $form_state['values']['revision'];
  $type = $form_state['values']['type'];

  db_update('node')
    ->fields(array('vid' => $vid, 'title' => $title, ))
    ->condition(array('nid' => $nid))
    ->execute();
             
  // Clear the cache so an anonymous poster can see the changes
  cache_clear_all();
  drupal_set_message(t('The selected revision has been published.'));
  watchdog('content', '@type: published %title revision %revision', array('@type' => t($type), '%title' => $title, '%revision' => $vid), WATCHDOG_NOTICE, l(t('view'), "node/$nid/revisions/$vid/view"));
  $form_state['redirect'] = 'node/' . $nid;
}

function revision_moderation_schema_alter(&$schema) {
  $schema['node']['fields']['moderate'] = array(
      'description' => 'A boolean indicating whether the node "in moderation" used by Revision Moderation.',
      'type' => 'int',
      'not null' => TRUE,
      'default' => 0,
      );
}