WordPress/wp-admin/revision.php

<?php
/**
 * Revisions administration panel.
 *
 * @package WordPress
 * @subpackage Administration
 */

/** WordPress Administration Bootstrap */
require_once('./admin.php');
wp_reset_vars( array( 'revision', 'action' ) );

$revision_id = absint( $revision );
$redirect = 'edit.php';

switch ( $action ) :
case 'restore' :
	if ( ! $revision = wp_get_post_revision( $revision_id ) )
		break;

	if ( ! current_user_can( 'edit_post', $revision->post_parent ) )
		break;


	if ( ! $post = get_post( $revision->post_parent ) )
		break;

	// Revisions disabled (previously checked autosavegs && ! wp_is_post_autosave( $revision ))
	if ( ( ! WP_POST_REVISIONS || ! post_type_supports( $post->post_type, 'revisions' ) ) ) {
		$redirect = 'edit.php?post_type=' . $post->post_type;
		break;
	}

	check_admin_referer( "restore-post_{$revision->ID}" );

	wp_restore_post_revision( $revision->ID );
	$redirect = add_query_arg( array( 'message' => 5, 'revision' => $revision->ID ), get_edit_post_link( $post->ID, 'url' ) );
	break;
case 'view' :
case 'edit' :
default :
	if ( ! $revision = wp_get_post_revision( $revision_id ) )
		break;
	if ( ! $post = get_post( $revision->post_parent ) )
		break;

	if ( ! current_user_can( 'read_post', $revision->ID ) || ! current_user_can( 'read_post', $post->ID ) )
		break;

	// Revisions disabled and we're not looking at an autosave
	if ( ! wp_revisions_enabled( $post ) && ! wp_is_post_autosave( $revision ) ) {
		$redirect = 'edit.php?post_type=' . $post->post_type;
		break;
	}

	$post_title = '<a href="' . get_edit_post_link() . '">' . get_the_title() . '</a>';
	$h2 = sprintf( __( 'Compare Revisions of &#8220;%1$s&#8221;' ), $post_title );
	$title = __( 'Revisions' );

	$redirect = false;
	break;
endswitch;

// Empty post_type means either malformed object found, or no valid parent was found.
if ( ! $redirect && empty( $post->post_type ) )
	$redirect = 'edit.php';

if ( ! empty( $redirect ) ) {
	wp_redirect( $redirect );
	exit;
}

// This is so that the correct "Edit" menu item is selected.
if ( ! empty( $post->post_type ) && 'post' != $post->post_type )
	$parent_file = $submenu_file = 'edit.php?post_type=' . $post->post_type;
else
	$parent_file = $submenu_file = 'edit.php';

wp_enqueue_script( 'revisions' );


$settings = array(
	'post_id'     => $post->ID,
	'nonce'       => wp_create_nonce( 'revisions-ajax-nonce' ),
	'revision_id' => $revision_id
);

wp_localize_script( 'revisions', 'wpRevisionsSettings', $settings );

/* Revisions Help Tab */

$revisions_overview  = '<p>' . __( 'This screen is used for managing your content revisions.' ) . '</p>';
$revisions_overview .= '<p>' . __( 'Revisions are saved copies of your post or page, which are periodically created as you update your content. The red text on the left shows the content that was removed. The green text on the right shows the content that was added.' ) . '</p>';
$revisions_overview .= '<p>' . __( 'From this screen you can review, compare, and restore revisions:' ) . '</p>';
$revisions_overview .= '<ul><li>' . __( 'To navigate between revisions, <strong>drag the slider arrow left or right</strong> or <strong>use the Previous or Next buttons</strong>.' ) . '</li>';
$revisions_overview .= '<li>' . __( 'Compare two different revisions by <strong>selecting the &#8220;Compare two revisions&#8221; box</strong> to the side.' ) . '</li>';
$revisions_overview .= '<li>' . __( 'To restore a revision, <strong>click Restore This Revision</strong>.' ) . '</li></ul>';

get_current_screen()->add_help_tab( array(
	'id'      => 'revisions-overview',
	'title'   => __( 'Overview' ),
	'content' => $revisions_overview
) );

$revisions_sidebar  = '<p><strong>' . __( 'For more information:' ) . '</strong></p>';
$revisions_sidebar .= '<p>' . __( '<a href="http://codex.wordpress.org/Revision_Management" target="_blank">Revisions Management</a>' ) . '</p>';
$revisions_sidebar .= '<p>' . __( '<a href="http://wordpress.org/support/" target="_blank">Support Forums</a>' ) . '</p>';

get_current_screen()->set_help_sidebar( $revisions_sidebar );

require_once( './admin-header.php' );

?>

<div class="wrap">
	<?php screen_icon(); ?>
	<div id="revision-diff-container" class="current-version right-model-loading">
		<h2 class="long-header"><?php echo $h2; ?></h2>

		<div id="loading-status" class="updated message">
			<p><span class="spinner" ></span> <?php _e( 'Calculating revision diffs' ); ?></p>
		</div>

		<div class="diff-slider-ticks-wrapper">
			<div id="diff-slider-ticks"></div>
		</div>

		<div id="revision-interact"></div>

		<div id="revisions-diff"></div>
	</div>
</div>

<script id="tmpl-revisions-diff" type="text/html">
	<div id="toggle-revision-compare-mode">
		<label>
			<input type="checkbox" id="compare-two-revisions" />
			<?php esc_attr_e( 'Compare two revisions' ); ?>
		</label>
	</div>

	<div id="diff-header">
		<div id="diff-header-from" class="diff-header">
			<div id="diff-title-from" class="diff-title">
				<strong><?php _ex( 'From:', 'Followed by post revision info' ); ?></strong> {{{ data.titleFrom }}}
			</div>
		</div>

		<div id="diff-header-to" class="diff-header">
			<div id="diff-title-to" class="diff-title">
				<strong><?php _ex( 'To:', 'Followed by post revision info' ); ?></strong> {{{ data.titleTo }}}
			</div>

			<input type="button" id="restore-revision" class="button button-primary" data-restore-link="{{{ data.restoreLink }}}" value="<?php esc_attr_e( 'Restore This Revision' )?>" />
		</div>
	</div>

	</div>

	<div id="diff-table">{{{ data.diff }}}</div>
</script>

<script id="tmpl-revision-interact" type="text/html">
	<div id="diff-previous-revision">
		<input class="button" type="button" id="previous" value="<?php echo esc_attr_x( 'Previous', 'Button label for a previous revision' ); ?>" />
	</div>

	<div id="diff-next-revision">
		<input class="button" type="button" id="next" value="<?php echo esc_attr_x( 'Next', 'Button label for a next revision' ); ?>" />
	</div>

	<div id="diff-slider" class="wp-slider"></div>
</script>

<script id="tmpl-revision-ticks" type="text/html">
	<div class="revision-tick completed-{{{ data.completed }}} scope-of-changes-{{{ data.scopeOfChanges }}}"></div>
</script>
<?php
require_once( './admin-footer.php' );