From c531d96f6617663dae8534aba2623f541c7d12de Mon Sep 17 00:00:00 2001
From: butlerx <butlerx@notthe.cloud>
Date: Thu, 1 Jun 2017 09:47:52 +0100
Subject: [PATCH] check if reveal theme exists

---
 lib/response.js | 3 ++-
 lib/utils.js    | 9 +++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/response.js b/lib/response.js
index fec6c561..cda484e7 100755
--- a/lib/response.js
+++ b/lib/response.js
@@ -13,6 +13,7 @@ var moment = require('moment')
 var config = require('./config')
 var logger = require('./logger')
 var models = require('./models')
+var utils = require('./utils')
 
 // public
 var response = {
@@ -574,7 +575,7 @@ function showPublishSlide (req, res, next) {
         updatetime: updatetime,
         url: origin,
         body: markdown,
-        theme: meta.slideOptions.theme,
+        theme: utils.isRevealTheme(meta.slideOptions.theme),
         meta: JSON.stringify(extracted.meta),
         useCDN: config.usecdn,
         owner: note.owner ? note.owner.id : null,
diff --git a/lib/utils.js b/lib/utils.js
index d9289dca..fe70a0f1 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -1,4 +1,6 @@
 'use strict'
+const fs = require('fs')
+const path = require('path')
 
 exports.isSQLite = function isSQLite (sequelize) {
   return sequelize.options.dialect === 'sqlite'
@@ -23,3 +25,10 @@ exports.getImageMimeType = function getImageMimeType (imagePath) {
       return undefined
   }
 }
+
+exports.isRevealTheme = function isRevealTheme (theme) {
+  if (fs.existsSync(path.join(process.cwd(), 'public', 'build', 'reveal.js', 'css', 'theme', theme + '.css'))) {
+    return theme
+  }
+  return undefined
+}