Edit Flow "plugin" (hack) to autosave unsubmitted Editorial Comment text when post is saved

edit-flow-autosave-comments-not-a-real-plugin.php

<?php
/**
 * EDIT FLOW:  wp_insert_post action to autosave "draft" editorial comments in post meta field 
 * 
 * Currently (2016-10-06) Edit Flow has no handling of unsubmitted editorial comments in the textarea
 * when the post is saved, so saving your post deletes your comment unless you submitted it, which is awful. 
 * 
 * This function hooks into wp_insert_post where the value of the textarea is present (but ignored by default) 
 * and if found, saves the text (and ID of parent comment if it was a specific reply) to a postmeta field
 * keyed on the user who saves the post. 
 * 
 * Effect is that we can then re-insert the value when the page loads, and give the effect of EF having
 * saved the comment draft while the post was being saved. 
 * 
 * NOTE: THIS IS HOPEFULLY TEMPORARY WHILE EDIT FLOW ADDS THIS FEATURE TO THE CORE PLUGIN. REMOVE WHEN POSSIBLE.
 * 
 * @see gv_edit_flow_comment_autosave_js() which handles and inserts the postmeta value with jQuery
 * @see https://github.com/Automattic/Edit-Flow/issues/379 Feature request for core Edit Flow plugin
 * @param integer $post_id
 * @param array $post
 * @return type
 */
function gv_edit_flow_comment_autosave_wp_insert_post($post_id, $post) {
	/**
	 * 'replycontent' Text entered in the editorial comment textarea
	 * 'ef-post_id' EF-version of the post ID, seems ideal to avoid collisions as it should match EF form
	 * 'user_ID' ID of editing user who submitted form
	 */
	if (empty($_POST['replycontent']) OR empty($_POST['ef-post_id']) OR empty($_POST['user_ID']))
		return;
	
	/**
	 * Array of "draft" comment data to save in postmeta
	 */
	$saved_editorial_comment = array(
		'text' => $_POST['replycontent'],
		'parent' => '',
	);
	
	/**
	 * 'comment_parent' is ID of parent editorial comment
	 */
	if (!empty($_POST['ef-comment_parent']))
		$saved_editorial_comment['parent'] = $_POST['ef-comment_parent'];
	
	/**
	 * Prepare the postmeta key with user ID
	 */
	$editing_user_id = $_POST['user_ID'];	
	$postmeta_key = 'ef_ec_draft_' . $editing_user_id;

	/**
	 * Update/add the postmeta (intentionally replaces old value if present, shouldn't happen)
	 */
	$existing_postmeta = get_post_meta($post_id, $postmeta_key, 'single');
	if ($existing_postmeta)
		update_post_meta($post_id, $postmeta_key, $saved_editorial_comment, $existing_postmeta);
	else 
		add_post_meta($post_id, $postmeta_key, $saved_editorial_comment, 'unique');
}
add_action('wp_insert_post', 'gv_edit_flow_comment_autosave_wp_insert_post', '', 2);

/**
 * EDIT FLOW: Output jQuery on post editor screen to insert previously-saved "draft" editorial comment
 * 
 * Checks post meta for a field containing saved EF editorial comment text and if found, outputs
 * jQuery that clicks the correct "reply" button then inserts the text. 
 * 
 * Effect is as if the comment text was saved naturally during post save (it's removed by default).
 * 
 * NOTE: THIS IS HOPEFULLY TEMPORARY WHILE EDIT FLOW ADDS THIS FEATURE TO THE CORE PLUGIN. REMOVE WHEN POSSIBLE.
 *
 * @see gv_edit_flow_comment_autosave_wp_insert_post() Which hooks into wp_insert_post to save postmeta field
 * @see https://github.com/Automattic/Edit-Flow/issues/379 Feature request for core Edit Flow plugin
 * @global $post
 */
function gv_edit_flow_comment_autosave_js() {
	global $post;
	
	/**
	 * Get currently-editing user ID
	 */
	$editing_user_id = get_current_user_id();
	if (!$editing_user_id OR is_wp_error($editing_user_id))
		return;

	/**
	 * Get the comment draft as saved by gv_edit_flow_wp_insert_post()
	 * Will only exist if editing user had text in the form before saving
	 */
	$postmeta_key = 'ef_ec_draft_' . $editing_user_id;
	$editorial_comment_draft = get_post_meta($post->ID, $postmeta_key, 'single');
	
	/**
	 * If the comment draft is invalid exit
	 */
	if (!is_array($editorial_comment_draft) OR !isset($editorial_comment_draft['text'])) :
		// If the postmeta existed (it's invalid) delete it
		if ($editorial_comment_draft)
			delete_post_meta($post->ID, $postmeta_key);
		return;
	endif;

	/**
	 * Handle click_selector based on parentage
	 */
	// Default click selector is main "reply" button (no parent)
	$click_selector = "#ef-comment_respond";

	// If parent ID is present use it's sub-reply button
	$parent_id = '';
	if (!empty($editorial_comment_draft['parent'])) 
		$parent_id = $editorial_comment_draft['parent'];
	if ($parent_id) :
		$click_selector = "#comment-$parent_id .reply a";
	endif;

	/**
	 * Output jquery to click the appropriate submit button then insert the content
	 */
	$draft_text_json_encoded = json_encode($editorial_comment_draft['text']);

	?>
     <script>
	jQuery(document).ready(function(){			
		function gv_ef_insert_comment_draft() {
			jQuery("<?php echo $click_selector; ?>").click();
			jQuery("#ef-replycontent").val(<?php echo $draft_text_json_encoded; ?>);
		}
		gv_ef_insert_comment_draft();
	});
	</script>
	<?php
	
	/**
	 * Delete the postmeta 
	 */
	delete_post_meta($post->ID, $postmeta_key);
}
add_action( 'admin_head-post.php', 'gv_edit_flow_comment_autosave_js');
?>