button while editing a post.') .'';
return $output;
}
}
/**
* Implementation of hook_requirements().
* Checks if the diff modules is loaded after the node module in the hook ordering.
*/
function diff_requirements($phase) {
// Don't check when installing
if ($phase == 'install') {
return;
}
$modules = array_keys(module_list());
if (array_search('diff', $modules) <= array_search('node', $modules)) {
diff_autoadjust();
}
}
/**
* Implementation of hook_menu()
* The menu path 'node/$nid/revisions' is overriden with 'diff_diffs'.
*/
function diff_menu($may_cache) {
$items = array();
if (!$may_cache) {
if (arg(0) == 'node' && is_numeric(arg(1))) {
$node = node_load(arg(1));
if ($node->nid) {
$revisions_access = (user_access('view revisions') || user_access('administer nodes')) &&
node_access('view', $node) &&
db_result(db_query('SELECT COUNT(vid) FROM {node_revisions} WHERE nid = %d', arg(1))) > 1;
$items[] = array(
'path' => 'node/'. arg(1) .'/revisions', 'title' => t('Revisions'),
'callback' => 'diff_diffs',
'access' => $revisions_access,
'weight' => 4,
'type' => MENU_LOCAL_TASK,
);
}
}
}
return $items;
}
/**
* Adjust the module weights for diff to load after node module.
*/
function diff_autoadjust() {
$modules = array_keys(module_list());
if (array_search('diff', $modules) <= array_search('node', $modules)) {
module_load_install('diff');
diff_set_weight();
}
}
/**
* Menu callback for diff related activities.
*/
function diff_diffs() {
if (is_numeric(arg(1)) && arg(2) == 'revisions') {
$op = arg(3) ? arg(3) : 'overview';
switch ($op) {
case 'overview':
$node = node_load(arg(1));
if ((user_access('view revisions') || user_access('administer nodes')) && node_access('view', $node)) {
return diff_diffs_overview($node);
}
drupal_access_denied();
return;
case 'view':
if (is_numeric(arg(4)) && is_numeric(arg(5))) {
$node = node_load(arg(1));
if ($node->nid) {
if ((user_access('view revisions') || user_access('administer nodes')) && node_access('view', $node)) {
drupal_set_title(t('Diff for %title', array('%title' => $node->title)));
return diff_diffs_show($node, arg(4), arg(5));
}
drupal_access_denied();
return;
}
}
break;
default:
// A view, revert or delete operation from the orignial node module,
// so call the original node module to handle this.
return node_revisions();
break;
}
}
drupal_not_found();
}
/**
* Generate an overview table of older revisions of a node and provide
* an input form to select two revisions for a comparison.
*/
function diff_diffs_overview(&$node) {
$output = '';
drupal_set_title(t('Revisions for %title', array('%title' => $node->title)));
$output .= drupal_get_form('diff_node_revisions', $node);
return $output;
}
/**
* Input form to select two revisions.
*/
function diff_node_revisions(&$node) {
global $form_values;
$form = array();
$form['nid'] = array(
'#type' => 'hidden',
'#value' => $node->nid,
);
$revision_list = node_revision_list($node);
if (count($revision_list) > REVISION_LIST_SIZE) {
// If the list of revisions is longer than the number shown on one page split the array.
$page = isset($_GET['page']) ? $_GET['page'] : '0';
$revision_chunks = array_chunk(node_revision_list($node), REVISION_LIST_SIZE);
$revisions = $revision_chunks[$page];
// Set up global pager variables as would 'pager_query' do.
// These variables are then used in the theme('pager') call later.
global $pager_page_array, $pager_total, $pager_total_items;
$pager_total_items[0] = count($revision_list);
$pager_total[0] = ceil(count($revision_list) / REVISION_LIST_SIZE);
$pager_page_array[0] = max(0, min($page, ((int)$pager_total[0]) - 1));
} else {
$revisions = $revision_list;
}
$revert_permission = FALSE;
if ((user_access('revert revisions') || user_access('administer nodes')) && node_access('update', $node)) {
$revert_permission = TRUE;
}
$delete_permission = FALSE;
if (user_access('administer nodes')) {
$delete_permission = TRUE;
}
foreach ($revisions as $revision) {
$operations = array();
$revision_ids[$revision->vid] = '';
if ($revision->current_vid > 0) {
$form['info'][$revision->vid] = array(
'#value' => t('!date by !username', array(
'!date' => l(format_date($revision->timestamp, 'small'), "node/$node->nid"),
'!username' => theme('username', $revision)))
. (($revision->log != '') ? ''. filter_xss($revision->log) .'
' : ''),
);
}
else {
$form['info'][$revision->vid] = array(
'#value' => t('!date by !username', array(
'!date' => l(format_date($revision->timestamp, 'small'), "node/$node->nid/revisions/$revision->vid/view"),
'!username' => theme('username', $revision)))
. (($revision->log != '') ? ''. filter_xss($revision->log) .'
' : '')
);
if ($revert_permission) {
$operations[] = array('#value' => l(t('revert'), "node/$node->nid/revisions/$revision->vid/revert"));
}
if ($delete_permission) {
$operations[] = array('#value' => l(t('delete'), "node/$node->nid/revisions/$revision->vid/delete"));
}
// Set a dummy, even if the user has no permission for the other
// operations, so that we can check if the operations array is
// empty to know if the row denotes the current revision.
$operations[] = array();
}
$form['operations'][$revision->vid] = $operations;
}
$new_vid = key($revision_ids);
next($revision_ids);
$old_vid = key($revision_ids);
$form['diff']['old'] = array(
'#type' => 'radios',
'#options' => $revision_ids,
'#default_value' => $old_vid
);
$form['diff']['new'] = array(
'#type' => 'radios',
'#options' => $revision_ids,
'#default_value' => $new_vid
);
$form['submit'] = array('#type' => 'submit', '#value' => t('Show diff'));
if (count($revision_list) > REVISION_LIST_SIZE) {
$form['#suffix'] = theme('pager', NULL, REVISION_LIST_SIZE, 0);
}
return $form;
}
/**
* Theme function to display the revisions formular with means to select
* two revisions.
*/
function theme_diff_node_revisions($form) {
// Overview table:
$header = array(
t('Revision'),
array('data' => drupal_render($form['submit']), 'colspan' => 2),
array('data' => t('Operations'), 'colspan' => 2)
);
if (isset($form['info']) && is_array($form['info'])) {
foreach (element_children($form['info']) as $key) {
$row = array();
if (isset($form['operations'][$key][0])) {
// Note: even if the commands for revert and delete are not permitted,
// the array is not empty since we set a dummy in this case.
$row[] = drupal_render($form['info'][$key]);
$row[] = drupal_render($form['diff']['old'][$key]);
$row[] = drupal_render($form['diff']['new'][$key]);
$row[] = drupal_render($form['operations'][$key][0]);
$row[] = drupal_render($form['operations'][$key][1]);
$rows[] = $row;
}
else {
// its the current revision (no commands to revert or delete)
$row[] = array('data' => drupal_render($form['info'][$key]), 'class' => 'revision-current');
$row[] = array('data' => drupal_render($form['diff']['old'][$key]), 'class' => 'revision-current');
$row[] = array('data' => drupal_render($form['diff']['new'][$key]), 'class' => 'revision-current');
$row[] = array('data' => theme('placeholder', t('current revision')), 'class' => 'revision-current', 'colspan' => '2');
$rows[] = array(
'data' => $row,
'class' => 'error',
);
}
}
}
$output .= theme('table', $header, $rows);
$output .= drupal_render($form);
return $output;
}
/**
* Submit code for input form to select two revisions.
*/
function diff_node_revisions_submit($form_id, $form_values) {
// the ids are ordered so the old revision is always on the left
$old_vid = min($form_values['old'], $form_values['new']);
$new_vid = max($form_values['old'], $form_values['new']);
return 'node/'.$form_values['nid'].'/revisions/view/'.$old_vid.'/'.$new_vid;
}
/**
* Validation for input form to select two revisions.
*/
function diff_node_revisions_validate($form_id, $form_values) {
$old_vid = $form_values['old'];
$new_vid = $form_values['new'];
if ($old_vid==$new_vid || !$old_vid || !$new_vid) {
form_set_error('diff', t('Select different revisions to compare.'));
}
}
/**
* Create output string for a comparison of 'node' between
* versions 'old_vid' and 'new_vid'.
*/
function diff_diffs_show(&$node, $old_vid, $new_vid) {
$lame_revisions = node_revision_list($node);
foreach ($lame_revisions as $revision) {
$node_revisions[$revision->vid] = $revision;
}
$old_node = node_load($node->nid, $old_vid);
$new_node = node_load($node->nid, $new_vid);
// Generate table header (date, username, logmessage).
$old_header = t('!date by !username', array(
'!date' => l(format_date($old_node->revision_timestamp), "node/$node->nid/revisions/$old_node->vid/view"),
'!username' => theme('username', $node_revisions[$old_vid]),
));
$new_header = t('!date by !username', array(
'!date' => l(format_date($new_node->revision_timestamp), "node/$node->nid/revisions/$new_node->vid/view"),
'!username' => theme('username', $node_revisions[$new_vid]),
));
$old_log = $old_node->log != '' ? ''. filter_xss($old_node->log) .'
' : '';
$new_log = $new_node->log != '' ? ''. filter_xss($new_node->log) .'
' : '';
// Generate previous diff/next diff links.
$next_vid = _diff_get_next_vid($node_revisions, $new_vid);
if ($next_vid) {
$next_link = l(t('next diff >'), 'node/'. $node->nid .'/revisions/view/'. $new_vid .'/'. $next_vid);
}
else {
$next_link = '';
}
$prev_vid = _diff_get_previous_vid($node_revisions, $old_vid);
if ($prev_vid) {
$prev_link = l(t('< previous diff'), 'node/'. $node->nid .'/revisions/view/'. $prev_vid .'/'. $old_vid);
}
else {
$prev_link = '';
}
// display table
$output .= '';
$output .= ' | '. $old_header .' | | '. $new_header .' |
|---|
';
if ($new_log || $old_log) {
$output .= ' | '. $old_log .' | | '. $new_log .' |
';
}
$output .= ' | '. $prev_link .' | | '. $next_link .' |
';
$output .= _diff_table_body($old_node, $new_node);
$output .= '
';
$output .= '
';
if ($node->vid == $new_vid) {
$output .= ''. t('Current revision:') .'
';
}
else {
$output .= ''. t('Revision of !new_date:', array('!new_date' => format_date($new_node->revision_timestamp))) .'
';
}
// Don't include node links (final argument) when viewing the diff.
$output .= node_view($new_node, FALSE, FALSE, FALSE);
return $output;
}
/**
* Create the table body of the diff between $old_node and $new_node.
* The result is a html table part enclosed in tags.
*/
function _diff_table_body(&$old_node, &$new_node) {
drupal_add_css(drupal_get_path('module', 'diff') .'/diff.css', 'module', 'all', FALSE);
include_once('DiffEngine.php');
include_once('node.inc');
if (module_exists('upload')) {
include_once('upload.inc');
}
if (module_exists('content')) {
include_once('cck.inc');
}
$output = '';
$any_visible_change = false;
$node_diffs = module_invoke_all('diff', $old_node, $new_node);
foreach($node_diffs as $node_diff) {
$diff = new Diff($node_diff['old'], $node_diff['new']);
$formatter = new TableDiffFormatter();
if (isset($node_diff['format'])) {
$formatter->show_header = $node_diff['format']['show_header'];
}
$formatter_output = $formatter->format($diff);
if ($formatter_output) {
$output .= '| '. t('Changes to %name', array('%name' => $node_diff['name'])) .' |
';
$output .= $formatter_output;
$any_visible_change = true;
}
}
if (!$any_visible_change) {
$output .= '| ' .t('No visible changes') .' |
';
}
$output .= '';
return $output;
}
/**
* Get the entry in the revisions list after 'vid'.
* Returns false if 'vid' is the last entry.
*/
function _diff_get_next_vid(&$node_revisions, $vid) {
$previous = NULL;
foreach($node_revisions as $revision) {
if ($revision->vid == $vid) {
return ($previous ? $previous->vid : false);
}
$previous = $revision;
}
return false;
}
/**
* Get the entry in the revision list before 'vid'.
* Returns false if 'vid' is the first entry.
*/
function _diff_get_previous_vid(&$node_revisions, $vid) {
$previous = NULL;
foreach($node_revisions as $revision) {
if ($previous && $previous->vid == $vid) {
return $revision->vid;
}
$previous = $revision;
}
return false;
}
/**
* Implementation of hook_form_alter().
* Used to add a 'Preview changes' button on the node edit form.
*/
function diff_form_alter($form_id, &$form) {
if (isset($form['type']) && $form['type']['#value'] .'_node_form' == $form_id) {
if (user_access('view revisions') && $form['nid']['#value'] > 0) {
$form['preview_changes'] = array('#type' => 'button', '#value' => t('Preview changes'), '#weight' => 41);
// Change the form render callback to display the new button
$form['#theme'] = 'diff_node_form';
// Hijack the callback to handle showing of the diff if requested.
$form['#after_build'] = array('diff_node_form_add_changes');
}
}
}
/**
* A copy of the 'theme_node_form' function with the addition of the new button
* to show a diff of the changes.
*/
function theme_diff_node_form($form) {
$output = "\n\n";
return $output;
}
/**
* Callback for node edit form to prepend the changes or preview to the form.
*/
function diff_node_form_add_changes($form) {
global $form_values;
$op = isset($form_values['op']) ? $form_values['op'] : '';
if ($op == t('Preview changes')) {
$node = (object)$form_values;
$changes = '';
$changes .= _diff_table_body(node_load($form_values['nid']), $node);
$changes .= '
';
$form['#prefix'] = isset($form['#prefix']) ? $changes . $form['#prefix'] : $changes;
return $form;
}
else {
// call original function from node module
return node_form_add_preview($form);
}
}