--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/chords2halftone.php	Tue Mar 27 03:55:10 2012 -0400
@@ -0,0 +1,113 @@
+<?php
+
+if ( isset($_POST['text']) )
+{
+	$text = explode("\n", str_replace("\r\n", "\n", trim($_POST['text'])));
+	$chordline = false;
+	echo "<pre>";
+	foreach ( $text as $i => $line )
+	{
+		if ( $i == 0 )
+		{
+			echo "&lt;halftone title=\"" . htmlspecialchars(htmlspecialchars($line)) . "\"&gt;\n";
+		}
+		else if ( trim($line) == "" )
+		{
+			// do nothing
+		}
+		else if ( preg_match('/^(.*?(?:Verse|Chorus|Bridge).*?):\s*$/i', $line, $match) )
+		{
+			if ( $chordline )
+			{
+				$chordstack = preg_split("/([ \t]+)/", $chordline);
+				echo '(' . implode(") (", $chordstack) . ")\n";
+				$chordline = false;
+			}
+			
+			if ( $i > 3 )
+				echo "\n";
+			echo "= {$match[1]} =\n";
+		}
+		else if ( preg_match('/^\((.*?(?:Verse|Chorus|Bridge).*?)\)$/i', $line, $match) )
+		{
+			if ( $chordline )
+			{
+				$chordstack = preg_split("/([ \t]+)/", $chordline);
+				echo '(' . implode(") (", $chordstack) . ")\n";
+				$chordline = false;
+			}
+			echo "\n[{$match[1]}]\n";
+		}
+		else if ( preg_match('/^(\s*([A-G][#b]?(?:m?7?|2|add9|sus4|[Mm]aj[79])?)(\/[A-G][#b]?)?\s*)*$/', $line) )
+		{
+			if ( $chordline )
+			{
+				// we have two chord lines in a row... treat the last one as a transition
+				$chordstack = preg_split("/([ \t]+)/", $chordline);
+				echo '(' . implode(") (", $chordstack) . ")\n";
+			}
+			
+			// chord line
+			$chordline = $line;
+		}
+		else if ( $chordline && trim($line) )
+		{
+			// combine chord line with text line
+			$chordline = preg_split('/([ \t]+)/', $chordline, -1, PREG_SPLIT_DELIM_CAPTURE);
+			
+			if ( count($chordline) >= 2 && preg_match('/^\s*$/', $chordline[0]) && preg_match('/^\s*$/', $chordline[1]) )
+			{
+				$merger = array_shift($chordline);
+				$chordline[0] .= $merger;
+			}
+			
+			$chordstack = array();
+			for ( $j = 0; $j < count($chordline); $j++ )
+			{
+				if ( $j == 0 && !preg_match('/^\s*$/', $chordline[$j]) )
+				{
+					$chordstack[] = "({$chordline[$j]})";
+					if ( isset($chordline[$j+1]) )
+					{
+						$chordline[$j+1] .= str_repeat(' ', strlen($chordline[$j]));
+					}
+					continue;
+				}
+				// insert line up until this chord
+				$chordstack[] = substr($line, 0, strlen($chordline[$j]));
+				// chomp off the front of the line
+				$line = substr($line, strlen($chordline[$j]));
+				// insert this chord
+				if ( isset($chordline[++$j]) )
+				{
+					if ( !empty($chordline[$j]) )
+					{
+						$chordstack[] = "({$chordline[$j]})";
+						if ( isset($chordline[$j+1]) )
+						{
+							$chordline[$j+1] .= str_repeat(' ', strlen($chordline[$j]));
+						}
+					}
+				}
+			}
+			$chordstack[] = $line;
+			echo implode("", $chordstack) . "\n";
+			$chordline = false;
+		}
+		else
+		{
+			// assume it's a lyric line without chords...?
+			echo "$line\n";
+		}
+	}
+	
+	echo "&lt;/halftone&gt;";
+	echo "</pre>";
+	exit;
+}
+
+?>
+<form method="post">
+<p><textarea name="text" rows="20" cols="100"></textarea></p>
+<p><input type="submit" value="Make Halftone" /></p>
+</form>