--- /dev/null
+<?php
+/**
+ * WordPress Administration Revisions API.
+ *
+ * @package WordPress
+ * @subpackage Administration
+ */
+
+/**
+ * Get the revision UI diff.
+ *
+ * @since 3.6.0
+ *
+ * @param object $post The post object.
+ * @param int $compare_from The revision id to compare from.
+ * @param int $compare_to The revision id to come to.
+ *
+ * @return array|bool Associative array of a post's revisioned fields and their diffs.
+ * Or, false on failure.
+ */
+function wp_get_revision_ui_diff( $post, $compare_from, $compare_to ) {
+ if ( ! $post = get_post( $post ) )
+ return false;
+
+ if ( $compare_from ) {
+ if ( ! $compare_from = get_post( $compare_from ) )
+ return false;
+ } else {
+ // If we're dealing with the first revision...
+ $compare_from = false;
+ }
+
+ if ( ! $compare_to = get_post( $compare_to ) )
+ return false;
+
+ // If comparing revisions, make sure we're dealing with the right post parent.
+ // The parent post may be a 'revision' when revisions are disabled and we're looking at autosaves.
+ if ( $compare_from && $compare_from->post_parent !== $post->ID && $compare_from->ID !== $post->ID )
+ return false;
+ if ( $compare_to->post_parent !== $post->ID && $compare_to->ID !== $post->ID )
+ return false;
+
+ if ( $compare_from && strtotime( $compare_from->post_date_gmt ) > strtotime( $compare_to->post_date_gmt ) ) {
+ $temp = $compare_from;
+ $compare_from = $compare_to;
+ $compare_to = $temp;
+ }
+
+ // Add default title if title field is empty
+ if ( $compare_from && empty( $compare_from->post_title ) )
+ $compare_from->post_title = __( '(no title)' );
+ if ( empty( $compare_to->post_title ) )
+ $compare_to->post_title = __( '(no title)' );
+
+ $return = array();
+
+ foreach ( _wp_post_revision_fields() as $field => $name ) {
+ $content_from = $compare_from ? apply_filters( "_wp_post_revision_field_$field", $compare_from->$field, $field, $compare_from, 'from' ) : '';
+ $content_to = apply_filters( "_wp_post_revision_field_$field", $compare_to->$field, $field, $compare_to, 'to' );
+
+ $diff = wp_text_diff( $content_from, $content_to, array( 'show_split_view' => true ) );
+
+ if ( ! $diff && 'post_title' === $field ) {
+ // It's a better user experience to still show the Title, even if it didn't change.
+ // No, you didn't see this.
+ $diff = '<table class="diff"><colgroup><col class="content diffsplit left"><col class="content diffsplit middle"><col class="content diffsplit right"></colgroup><tbody><tr>';
+ $diff .= '<td>' . esc_html( $compare_from->post_title ) . '</td><td></td><td>' . esc_html( $compare_to->post_title ) . '</td>';
+ $diff .= '</tr></tbody>';
+ $diff .= '</table>';
+ }
+
+ if ( $diff ) {
+ $return[] = array(
+ 'id' => $field,
+ 'name' => $name,
+ 'diff' => $diff,
+ );
+ }
+ }
+ return $return;
+}
+
+/**
+ * Prepare revisions for JavaScript.
+ *
+ * @since 3.6.0
+ *
+ * @param object $post The post object.
+ * @param int $selected_revision_id The selected revision id.
+ * @param int $from (optional) The revision id to compare from.
+ *
+ * @return array An associative array of revision data and related settings.
+ */
+function wp_prepare_revisions_for_js( $post, $selected_revision_id, $from = null ) {
+ $post = get_post( $post );
+ $revisions = $authors = array();
+ $now_gmt = time();
+
+ $revisions = wp_get_post_revisions( $post->ID, array( 'order' => 'ASC', 'check_enabled' => false ) );
+ // If revisions are disabled, we only want autosaves and the current post.
+ if ( ! wp_revisions_enabled( $post ) ) {
+ foreach ( $revisions as $revision_id => $revision ) {
+ if ( ! wp_is_post_autosave( $revision ) )
+ unset( $revisions[ $revision_id ] );
+ }
+ $revisions = array( $post->ID => $post ) + $revisions;
+ }
+
+ $show_avatars = get_option( 'show_avatars' );
+
+ cache_users( wp_list_pluck( $revisions, 'post_author' ) );
+
+ $can_restore = current_user_can( 'edit_post', $post->ID );
+
+ foreach ( $revisions as $revision ) {
+ $modified = strtotime( $revision->post_modified );
+ $modified_gmt = strtotime( $revision->post_modified_gmt );
+ if ( $can_restore ) {
+ $restore_link = str_replace( '&', '&', wp_nonce_url(
+ add_query_arg(
+ array( 'revision' => $revision->ID,
+ 'action' => 'restore' ),
+ admin_url( 'revision.php' )
+ ),
+ "restore-post_{$revision->ID}"
+ ) );
+ }
+
+ if ( ! isset( $authors[ $revision->post_author ] ) ) {
+ $authors[ $revision->post_author ] = array(
+ 'id' => (int) $revision->post_author,
+ 'avatar' => $show_avatars ? get_avatar( $revision->post_author, 32 ) : '',
+ 'name' => get_the_author_meta( 'display_name', $revision->post_author ),
+ );
+ }
+
+ $autosave = (bool) wp_is_post_autosave( $revision );
+ $current = ! $autosave && $revision->post_modified_gmt === $post->post_modified_gmt;
+ if ( $current && ! empty( $current_id ) ) {
+ // If multiple revisions have the same post_modified_gmt, highest ID is current.
+ if ( $current_id < $revision->ID ) {
+ $revisions[ $current_id ]['current'] = false;
+ $current_id = $revision->ID;
+ } else {
+ $current = false;
+ }
+ } elseif ( $current ) {
+ $current_id = $revision->ID;
+ }
+
+ $revisions[ $revision->ID ] = array(
+ 'id' => $revision->ID,
+ 'title' => get_the_title( $post->ID ),
+ 'author' => $authors[ $revision->post_author ],
+ 'date' => date_i18n( __( 'M j, Y @ G:i' ), $modified ),
+ 'dateShort' => date_i18n( _x( 'j M @ G:i', 'revision date short format' ), $modified ),
+ 'timeAgo' => sprintf( __( '%s ago' ), human_time_diff( $modified_gmt, $now_gmt ) ),
+ 'autosave' => $autosave,
+ 'current' => $current,
+ 'restoreUrl' => $can_restore ? $restore_link : false,
+ );
+ }
+
+ // If a post has been saved since the last revision (no revisioned fields were changed)
+ // we may not have a "current" revision. Mark the latest revision as "current".
+ if ( empty( $current_id ) ) {
+ if ( $revisions[ $revision->ID ]['autosave'] ) {
+ $revision = end( $revisions );
+ while ( $revision['autosave'] ) {
+ $revision = prev( $revisions );
+ }
+ $current_id = $revision['id'];
+ } else {
+ $current_id = $revision->ID;
+ }
+ $revisions[ $current_id ]['current'] = true;
+ }
+
+ // Now, grab the initial diff
+ $compare_two_mode = is_numeric( $from );
+ if ( ! $compare_two_mode ) {
+ $found = array_search( $selected_revision_id, array_keys( $revisions ) );
+ if ( $found ) {
+ $from = array_keys( array_slice( $revisions, $found - 1, 1, true ) );
+ $from = reset( $from );
+ } else {
+ $from = 0;
+ }
+ }
+
+ $from = absint( $from );
+
+ $diffs = array( array(
+ 'id' => $from . ':' . $selected_revision_id,
+ 'fields' => wp_get_revision_ui_diff( $post->ID, $from, $selected_revision_id ),
+ ));
+
+ return array(
+ 'postId' => $post->ID,
+ 'nonce' => wp_create_nonce( 'revisions-ajax-nonce' ),
+ 'revisionData' => array_values( $revisions ),
+ 'to' => $selected_revision_id,
+ 'from' => $from,
+ 'diffData' => $diffs,
+ 'baseUrl' => parse_url( admin_url( 'revision.php' ), PHP_URL_PATH ),
+ 'compareTwoMode' => absint( $compare_two_mode ), // Apparently booleans are not allowed
+ 'revisionIds' => array_keys( $revisions ),
+ );
+}