From 531ea983fea6d86642c1f3efdc4becd8bd09390c Mon Sep 17 00:00:00 2001
From: Daniel Rudolf <github.com@daniel-rudolf.de>
Date: Sun, 29 Nov 2015 20:37:35 +0100
Subject: [PATCH] Catch YAML parse errors

---
 lib/Pico.php              | 17 ++++++++++++-----
 themes/default/index.twig |  9 +++++++++
 themes/default/style.css  | 14 +++++++++++++-
 3 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/lib/Pico.php b/lib/Pico.php
index 7f4b1c3b4..b1152170a 100644
--- a/lib/Pico.php
+++ b/lib/Pico.php
@@ -266,8 +266,8 @@ public function getThemesDir()
      * meta headers, processes Markdown, does Twig processing and returns
      * the rendered contents.
      *
-     * @return string           rendered Pico contents
-     * @throws RuntimeException thrown when a not recoverable error occurs
+     * @return string    rendered Pico contents
+     * @throws Exception thrown when a not recoverable error occurs
      */
     public function run()
     {
@@ -760,9 +760,13 @@ public function parseFileMeta($rawContent, array $headers)
         $pattern = "/^(\/(\*)|---)[[:blank:]]*(?:\r)?\n"
             . "(.*?)(?:\r)?\n(?(2)\*\/|---)[[:blank:]]*(?:(?:\r)?\n|$)/s";
         if (preg_match($pattern, $rawContent, $rawMetaMatches)) {
-            $yamlParser = new \Symfony\Component\Yaml\Parser();
-            $meta = $yamlParser->parse($rawMetaMatches[3]);
-            $meta = array_change_key_case($meta, CASE_LOWER);
+            try {
+                $yamlParser = new \Symfony\Component\Yaml\Parser();
+                $meta = $yamlParser->parse($rawMetaMatches[3]);
+                $meta = array_change_key_case($meta, CASE_LOWER);
+            } catch (\Symfony\Component\Yaml\Exception\ParseException $e) {
+                $meta['YAML_ParseError'] = $e->getMessage();
+            }
 
             foreach ($headers as $fieldId => $fieldName) {
                 $fieldName = strtolower($fieldName);
@@ -961,6 +965,9 @@ protected function readPages()
                 $meta = &$this->meta;
             }
 
+            // fallback to page id if page title is empty
+            $meta['title'] = (!empty($meta['title'])) ? $meta['title'] : $id;
+
             // build page data
             // title, description, author and date are assumed to be pretty basic data
             // everything else is accessible through $page['meta']
diff --git a/themes/default/index.twig b/themes/default/index.twig
index 25d8b19ba..9543986dc 100644
--- a/themes/default/index.twig
+++ b/themes/default/index.twig
@@ -32,6 +32,15 @@
     </header>
 
     <section id="content">
+        {% if meta.YAML_ParseError %}
+            <div class="error">
+                <div class="inner">
+                    <h2>Invalid YAML Front Matter</h2>
+                    <p>{{ meta.YAML_ParseError }}</p>
+                </div>
+            </div>
+        {% endif %}
+
         <div class="inner">
             {{ content }}
         </div>
diff --git a/themes/default/style.css b/themes/default/style.css
index d26f65a5e..16ebf5d9f 100644
--- a/themes/default/style.css
+++ b/themes/default/style.css
@@ -119,7 +119,6 @@ a:hover, a:active {
 }
 
 h1, h2, h3, h4, h5, h6 {
-    color: #000;
     line-height: 1.2em;
     margin-bottom: 0.6em;
 }
@@ -279,6 +278,19 @@ blockquote {
 .clearfix {
     *zoom: 1;
 }
+.error {
+    margin: -80px 0 80px 0;
+    padding: 1em 0;
+    background-color: #F0DDDD;
+    color: #AA4444;
+}
+.error h2 {
+    font-size: 1.5em;
+    font-weight: bold;
+}
+.error p:last-child {
+    margin-bottom: 0;
+}
 
 /* Media Queries
 /*---------------------------------------------*/