+/**
+ * Creates autosave data for the specified post from $_POST data.
+ *
+ * @package WordPress
+ * @subpackage Post_Revisions
+ * @since 2.6.0
+ *
+ * @uses _wp_translate_postdata()
+ * @uses _wp_post_revision_fields()
+ *
+ * @return unknown
+ */
+function wp_create_post_autosave( $post_id ) {
+ $translated = _wp_translate_postdata( true );
+ if ( is_wp_error( $translated ) )
+ return $translated;
+
+ // Only store one autosave. If there is already an autosave, overwrite it.
+ if ( $old_autosave = wp_get_post_autosave( $post_id ) ) {
+ $new_autosave = _wp_post_revision_fields( $_POST, true );
+ $new_autosave['ID'] = $old_autosave->ID;
+ $new_autosave['post_author'] = get_current_user_id();
+ return wp_update_post( $new_autosave );
+ }
+
+ // _wp_put_post_revision() expects unescaped.
+ $_POST = stripslashes_deep($_POST);
+
+ // Otherwise create the new autosave as a special post revision
+ return _wp_put_post_revision( $_POST, true );
+}
+
+/**
+ * Save draft or manually autosave for showing preview.
+ *
+ * @package WordPress
+ * @since 2.7.0
+ *
+ * @uses get_post_status()
+ * @uses edit_post()
+ * @uses get_post()
+ * @uses current_user_can()
+ * @uses wp_die()
+ * @uses wp_create_post_autosave()
+ * @uses add_query_arg()
+ * @uses wp_create_nonce()
+ *
+ * @return str URL to redirect to show the preview
+ */
+function post_preview() {
+
+ $post_ID = (int) $_POST['post_ID'];
+ $status = get_post_status( $post_ID );
+ if ( 'auto-draft' == $status )
+ wp_die( __('Preview not available. Please save as a draft first.') );
+
+ if ( isset($_POST['catslist']) )
+ $_POST['post_category'] = explode(",", $_POST['catslist']);
+
+ if ( isset($_POST['tags_input']) )
+ $_POST['tags_input'] = explode(",", $_POST['tags_input']);
+
+ if ( $_POST['post_type'] == 'page' || empty($_POST['post_category']) )
+ unset($_POST['post_category']);
+
+ $_POST['ID'] = $post_ID;
+ $post = get_post($post_ID);
+
+ if ( 'page' == $post->post_type ) {
+ if ( !current_user_can('edit_page', $post_ID) )
+ wp_die(__('You are not allowed to edit this page.'));
+ } else {
+ if ( !current_user_can('edit_post', $post_ID) )
+ wp_die(__('You are not allowed to edit this post.'));
+ }
+
+ if ( 'draft' == $post->post_status ) {
+ $id = edit_post();
+ } else { // Non drafts are not overwritten. The autosave is stored in a special post revision.
+ $id = wp_create_post_autosave( $post->ID );
+ if ( ! is_wp_error($id) )
+ $id = $post->ID;
+ }
+
+ if ( is_wp_error($id) )
+ wp_die( $id->get_error_message() );
+
+ if ( $_POST['post_status'] == 'draft' ) {
+ $url = add_query_arg( 'preview', 'true', get_permalink($id) );
+ } else {
+ $nonce = wp_create_nonce('post_preview_' . $id);
+ $url = add_query_arg( array( 'preview' => 'true', 'preview_id' => $id, 'preview_nonce' => $nonce ), get_permalink($id) );
+ }
+
+ return $url;
+}