labels of reference links should be case insensitive

Parsedown.php

@@ -205,7 +205,7 @@ class Parsedown
 			
 			# Quick Paragraph 
 			
-			if ($line[0] >= 'A' and $line[0] !== '_' and $line[0] !== '[')
+			if ($line[0] >= 'a' or $line[0] >= 'A' and $line[0] <= 'Z')
 			{
 				goto paragraph; # trust me 
 			}
@@ -277,13 +277,13 @@ class Parsedown
 			
 			# ~ 
 			
-			$pure_line = ltrim($line);
+			$pure_line = $line[0] !== ' ' ? $line : ltrim($line);
 			
 			# Link Reference 
 			
 			if ($pure_line[0] === '[' and preg_match('/^\[(.+?)\]:[ ]*([^ ]+)/', $pure_line, $matches))
 			{
-				$label = $matches[1];
+				$label = strtolower($matches[1]);
 				$url = trim($matches[2], '<>');
 				
 				$this->reference_map[$label] = $url;
@@ -560,11 +560,13 @@ class Parsedown
 		
 		# Inline Link / Image 
 		
-		if (strpos($text, '](') !== FALSE and preg_match_all('/(!?)(\[((?:[^][]+|(?2))*)\])\((.*?)\)/', $text, $matches, PREG_SET_ORDER)) # inline 
+		if (strpos($text, '](') !== FALSE and preg_match_all('/(!?)(\[((?:[^\[\]]|(?2))*)\])\((.*?)\)/', $text, $matches, PREG_SET_ORDER)) # inline 
 		{
 			foreach ($matches as $matches)
 			{
-				$url = $this->escape_special_characters($matches[4]);
+				$url = $matches[4];
+				
+				strpos($url, '&') !== FALSE and $url = preg_replace('/&(?!#?\w+;)/', '&amp;', $url);
 				
 				if ($matches[1]) # image 
 				{
@@ -604,7 +606,8 @@ class Parsedown
 				if (isset($this->reference_map[$link_definition]))
 				{
 					$url = $this->reference_map[$link_definition];
-					$url = $this->escape_special_characters($url);
+					
+					strpos($url, '&') !== FALSE and $url = preg_replace('/&(?!#?\w+;)/', '&amp;', $url);
 					
 					if ($matches[1]) # image 
 					{
@@ -636,7 +639,9 @@ class Parsedown
 		{
 			foreach ($matches as $matches)
 			{
-				$url = $this->escape_special_characters($matches[1]);
+				$url = $matches[1];
+				
+				strpos($url, '&') !== FALSE and $url = preg_replace('/&(?!#?\w+;)/', '&amp;', $url);
 				
 				$element = '<a href=":href">:text</a>';
 				$element = str_replace(':text', $url, $element);
@@ -656,8 +661,9 @@ class Parsedown
 		
 		# ~ 
 		
-		$text = $this->escape_special_characters($text);
-
+		strpos($text, '&') !== FALSE and $text = preg_replace('/&(?!#?\w+;)/', '&amp;', $text);
+		strpos($text, '<') !== FALSE and $text = preg_replace('/<(?!\/?\w.*?>)/', '&lt;', $text);
+		
 		# ~ 
 		
 		if (strpos($text, '_') !== FALSE)
@@ -676,13 +682,4 @@ class Parsedown
 		
 		return $text;
 	}
-	
-	private function escape_special_characters($text)
-	{
-		strpos($text, '&') !== FALSE and $text = preg_replace('/&(?!#?\w+;)/', '&amp;', $text);
-		
-		$text = str_replace('<', '&lt;', $text);
-		
-		return $text;
-	}
 }

tests/data/reference_link.html

@@ -2,6 +2,7 @@
 <p>Here's <a href="http://parsedown.org">one</a> on the next line.</p>
 <p>Here's <a href="http://parsedown.org/tests/">one</a> with a different URL.</p>
 <p>Here's <a href="http://parsedown.org">one</a> with a semantic name.</p>
+<p>Here's <a href="http://parsedown.org">one</a> with an upper case label definition.</p>
 <p>Here's <a href="http://parsedown.org">one</a> with definition name on the next line.</p>
 <p>Here's [one][404] with no definition.</p>
 <p>Here's an image: <img alt="Markdown Logo" src="/md.png"></p>

tests/data/reference_link.md

@@ -13,6 +13,10 @@ Here's [one][website] with a semantic name.
 
 [website]: http://parsedown.org
 
+Here's [one][case] with an upper case label definition.
+
+[CASE]: http://parsedown.org
+
 Here's [one]
 [website] with definition name on the next line.
 

tests/data/span_level_html.html

@@ -0,0 +1 @@
+<p>Here's an <b>important</b> <a href=''>link</a>.</p>

tests/data/span_level_html.md

@@ -0,0 +1 @@
+Here's an <b>important</b> <a href=''>link</a>.

tests/data/special_characters.html

@@ -4,5 +4,6 @@
 <p>4 &lt; 5 and 6 > 5.</p>
 <p>Here's a <a href="http://example.com/?foo=1&amp;bar=2">link</a> with an ampersand in the URL.</p>
 <p>Here's an inline <a href="/script?foo=1&amp;bar=2">link</a>.</p>
+<p><a href="http://example.com/autolink?a=1&amp;b=2">http://example.com/autolink?a=1&amp;b=2</a></p>
 <hr />
 <p>Based on <a href="http://daringfireball.net/projects/downloads/MarkdownTest_1.0.zip">the original</a> test suite.</p>

tests/data/special_characters.md

@@ -1,6 +1,6 @@
 AT&T has an ampersand in their name.
 
-AT&T is another way to write it.
+AT&T is another way to write it.
 
 This & that.
 
@@ -12,6 +12,8 @@ Here's an inline [link](/script?foo=1&bar=2).
 
 [1]: http://example.com/?foo=1&bar=2
 
+<http://example.com/autolink?a=1&b=2>
+
 ---
 
 Based on [the original](http://daringfireball.net/projects/downloads/MarkdownTest_1.0.zip) test suite.