Several bugfixes and improvements.
- Better key detection by using sus4 as a hint
- Recognize major seventh, diminished and augmented chords
- Better handling of lines which are a label followed by several chords (i.e. "Intro: (C) (G) (Am) (F)")
<?php
/**!info**
{
"Plugin Name" : "Halftone",
"Plugin URI" : "http://enanocms.org/plugin/halftone",
"Description" : "Allows semantic input and transposition of chord sheets.",
"Author" : "Dan Fuhry",
"Version" : "0.1",
"Author URI" : "http://enanocms.org/",
"Version list" : ['0.1']
}
**!*/
$plugins->attachHook('render_wikiformat_posttemplates', 'halftone_process_tags($text);');
$plugins->attachHook('html_attribute_whitelist', '$whitelist["halftone"] = array("title", "transpose");');
$plugins->attachHook('session_started', 'register_special_page(\'HalftoneRender\', \'Halftone AJAX render handler\', false);');
define('KEY_C', 0);
define('KEY_D', 2);
define('KEY_E', 4);
define('KEY_F', 5);
define('KEY_G', 7);
define('KEY_A', 9);
define('KEY_B', 11);
define('KEY_C_SHARP', 1);
define('KEY_E_FLAT', 3);
define('KEY_F_SHARP', 6);
define('KEY_G_SHARP', 8);
define('KEY_B_FLAT', 10);
define('ACC_FLAT', -1);
define('ACC_SHARP', 1);
$circle_of_fifths = array(KEY_C, KEY_G, KEY_D, KEY_A, KEY_E, KEY_B, KEY_F_SHARP, KEY_C_SHARP, KEY_G_SHARP, KEY_E_FLAT, KEY_B_FLAT, KEY_F);
$accidentals = array(
KEY_C => ACC_FLAT,
KEY_G => ACC_SHARP,
KEY_D => ACC_SHARP,
KEY_A => ACC_SHARP,
KEY_E => ACC_SHARP,
KEY_B => ACC_SHARP,
KEY_F_SHARP => ACC_SHARP,
KEY_C_SHARP => ACC_SHARP,
KEY_G_SHARP => ACC_FLAT,
KEY_E_FLAT => ACC_FLAT,
KEY_B_FLAT => ACC_FLAT,
KEY_F => ACC_FLAT
);
function get_consonants($root_key)
{
global $circle_of_fifths;
$first = $root_key;
$key = array_search($root_key, $circle_of_fifths);
$fourth = $circle_of_fifths[(($key - 1) + count($circle_of_fifths)) % count($circle_of_fifths)];
$fifth = $circle_of_fifths[($key + 1) % count($circle_of_fifths)];
$minor1 = $circle_of_fifths[($key + 2) % count($circle_of_fifths)];
$minor2 = $circle_of_fifths[($key + 3) % count($circle_of_fifths)];
$minor3 = $circle_of_fifths[($key + 4) % count($circle_of_fifths)];
$result = array(
'first' => $first,
'fourth' => $fourth,
'fifth' => $fifth,
'minors' => array($minor1, $minor2, $minor3)
);
return $result;
}
function get_sharp($chord)
{
return key_to_name(name_to_key($chord), ACC_SHARP);
}
function detect_key($chord_list)
{
$majors = array();
$minors = array();
$sharp_or_flat = ACC_SHARP;
// sus4 chords are also a great indicator since they are almost always
// used exclusively on the fifth
$have_sus4 = false;
// index which chords are used in the song
foreach ( $chord_list as $chord )
{
// discard bass note
list($chord) = explode('/', $chord);
$match = array();
preg_match('/((?:[Mm]?7?|2|5|6|add9|sus4|[Mm]aj[79]|dim|aug)?)$/', $chord, $match);
if ( !empty($match[1]) )
{
$chord = str_replace_once($match[1], '', $chord);
if ( $match[1] === 'sus4' )
$have_sus4 = $chord;
}
$sharp_or_flat = get_sharp($chord) == $chord ? ACC_SHARP : ACC_FLAT;
$chord = get_sharp($chord);
if ( $match[1] == 'm' || $match[1] == 'm7' )
{
// minor chord
if ( !isset($minors[$chord]) )
$minors[$chord] = 0;
$minors[$chord]++;
}
else
{
// major chord
if ( !isset($majors[$chord]) )
$majors[$chord] = 0;
$majors[$chord]++;
}
}
/*
// remove very low scorers
foreach ( $majors as $key => $count )
{
if ( $count < 1 )
unset($majors[$key]);
}
*/
// now we go through each of the detected major chords, calculate its consonants, and determine how many of its consonants are present in the song.
$scores = array();
foreach ( $majors as $key => $count )
{
$scores[$key] = 0;
$consonants = get_consonants(name_to_key($key));
if ( isset($majors[key_to_name($consonants['fourth'])]) )
$scores[$key] += 2;
if ( isset($majors[key_to_name($consonants['fifth'])]) )
$scores[$key] += $have_sus4 === key_to_name($consonants['fifth']) ? 4 : 2;
if ( isset($majors[key_to_name($consonants['minors'][0])]) )
$scores[$key] += 1;
if ( isset($majors[key_to_name($consonants['minors'][1])]) )
$scores[$key] += 2;
if ( isset($majors[key_to_name($consonants['minors'][2])]) )
$scores[$key] += 1;
}
$winner_val = -1;
$winner_key = '';
foreach ( $scores as $key => $score )
{
if ( $score > $winner_val )
{
$winner_val = $score;
$winner_key = $key;
}
}
$winner_key = key_to_name(name_to_key($winner_key), $sharp_or_flat);
return $winner_key;
}
function key_to_name($root_key, $accidental = ACC_SHARP)
{
switch($root_key)
{
case KEY_C:
return 'C';
case KEY_D:
return 'D';
case KEY_E:
return 'E';
case KEY_F:
return 'F';
case KEY_G:
return 'G';
case KEY_A:
return 'A';
case KEY_B:
return 'B';
case KEY_C_SHARP:
return $accidental == ACC_FLAT ? 'Db' : 'C#';
case KEY_E_FLAT:
return $accidental == ACC_FLAT ? 'Eb' : 'D#';
case KEY_F_SHARP:
return $accidental == ACC_FLAT ? 'Gb' : 'F#';
case KEY_G_SHARP:
return $accidental == ACC_FLAT ? 'Ab' : 'G#';
case KEY_B_FLAT:
return $accidental == ACC_FLAT ? 'Bb' : 'A#';
default:
return false;
}
}
function name_to_key($name)
{
switch($name)
{
case 'C': return KEY_C;
case 'D': return KEY_D;
case 'E': return KEY_E;
case 'F': return KEY_F;
case 'G': return KEY_G;
case 'A': return KEY_A;
case 'B': return KEY_B;
case 'C#': case 'Db': return KEY_C_SHARP;
case 'D#': case 'Eb': return KEY_E_FLAT;
case 'F#': case 'Gb': return KEY_F_SHARP;
case 'G#': case 'Ab': return KEY_G_SHARP;
case 'A#': case 'Bb': return KEY_B_FLAT;
default: return false;
}
}
function prettify_accidentals($chord)
{
if ( count(explode('/', $chord)) > 1 )
{
list($upper, $lower) = explode('/', $chord);
return prettify_accidentals($upper) . '/' . prettify_accidentals($lower);
}
if ( strlen($chord) < 2 )
return $chord;
if ( $chord{1} == 'b' )
{
$chord = $chord{0} . '♭' . substr($chord, 2);
}
else if ( $chord{1} == '#' )
{
$chord = $chord{0} . '♯' . substr($chord, 2);
}
return $chord;
}
function transpose_chord($chord, $increment, $accidental = false)
{
global $circle_of_fifths;
if ( count(explode('/', $chord)) > 1 )
{
list($upper, $lower) = explode('/', $chord);
return transpose_chord($upper, $increment, $accidental) . '/' . transpose_chord($lower, $increment, $accidental);
}
// shave off any wacky things we're doing to the chord (minor, seventh, etc.)
preg_match('/((?:[Mm]?7?|2|5|6|add9|sus4|[Mm]aj[79]|dim|aug)?)$/', $chord, $match);
// find base chord
if ( !empty($match[1]) )
$chord = str_replace($match[1], '', $chord);
// what's our accidental? allow it to be specified, and autodetect if it isn't
if ( !$accidental )
$accidental = strstr($chord, '#') ? ACC_SHARP : ACC_FLAT;
// convert to numeric value
$key = name_to_key($chord);
if ( $key === false )
// should never happen
return "[TRANSPOSITION FAILED: " . $chord . $match[1] . "]";
// transpose
$key = (($key + $increment) + count($circle_of_fifths)) % count($circle_of_fifths);
// return result
$kname = key_to_name($key, $accidental);
if ( !$kname )
// again, should never happen
return "[TRANSPOSITION FAILED: " . $chord . $match[1] . " + $increment (->$key)]";
$result = $kname . $match[1];
// echo "$chord{$match[1]} + $increment = $result<br />";
return $result;
}
function halftone_process_tags(&$text)
{
global $circle_of_fifths;
static $css_added = false;
if ( !$css_added )
{
global $template;
$template->preload_js(array('jquery', 'jquery-ui'));
$template->add_header('
<style type="text/css">
div.halftone {
page-break-before: always;
}
span.halftone-line {
display: block;
padding-top: 10pt;
position: relative; /* allows the absolute positioning in chords to work */
}
span.halftone-chord {
position: absolute;
top: 0pt;
color: rgb(27, 104, 184);
}
span.halftone-line.labeled span.halftone-chord {
position: static;
}
span.halftone-chord.sequential {
padding-left: 20pt;
}
div.halftone-key-select {
float: right;
}
</style>
<script type="text/javascript">
addOnloadHook(function()
{
var first_ht = $("div.halftone").get(0);
if ( first_ht )
first_ht.style.pageBreakBefore = "auto";
$("select.halftone-key").change(function()
{
var me = this;
var src = $(this.parentNode.parentNode).attr("halftone:src");
ajaxPost(makeUrlNS("Special", "HalftoneRender", "transpose=" + $(this).val()) + "&tokey=" + $("option:selected", this).attr("halftone:abs"), "src=" + encodeURIComponent(src), function(ajax)
{
if ( ajax.readyState == 4 && ajax.status == 200 )
{
var $songbody = $("div.halftone-song", me.parentNode.parentNode);
$songbody.html(ajax.responseText);
}
});
});
});
</script>
');
$css_added = true;
}
if ( preg_match_all('/<halftone(.*?)>(.+?)<\/halftone>/s', $text, $matches) )
{
foreach ( $matches[0] as $i => $whole_match )
{
$attribs = decodeTagAttributes($matches[1][$i]);
$song_title = isset($attribs['title']) ? $attribs['title'] : 'Untitled song';
$chord_list = array();
$inner = trim($matches[2][$i]);
$song = halftone_render_body($inner, $chord_list);
$src = base64_encode($whole_match);
$origkey = $key = name_to_key(detect_key($chord_list));
if ( isset($attribs['transpose']) && is_int($tokey = name_to_key($attribs['transpose'])) )
{
// re-render in new key
$transpose = $tokey - $key;
$song = halftone_render_body($inner, $chord_list, $tokey, $transpose);
$key = $tokey;
}
$select = '<select class="halftone-key">';
for ( $i = 0; $i < 12; $i++ )
{
$label = in_array($i, array(KEY_C_SHARP, KEY_E_FLAT, KEY_F_SHARP, KEY_G_SHARP, KEY_B_FLAT)) ? sprintf("%s/%s", key_to_name($i, ACC_SHARP), key_to_name($i, ACC_FLAT)) : key_to_name($i);
$label = prettify_accidentals($label);
$sel = $key == $i ? ' selected="selected"' : '';
$select .= sprintf("<option%s value=\"%d\" halftone:abs=\"%d\">%s</option>", $sel, $i - $origkey, $i, $label);
}
$select .= '</select>';
$headid = 'song:' . sanitize_page_id($song_title);
$text = str_replace_once($whole_match, "<div id=\"$headid\" class=\"halftone\" halftone:src=\"$src\"><div class=\"halftone-key-select\">$select</div><h1 class=\"halftone-title\">$song_title</h1>\n\n<div class=\"halftone-song\">\n" . $song . "</div></div>", $text);
}
}
}
function halftone_render_body($inner, &$chord_list, $inkey = false, $transpose = 0)
{
global $accidentals;
$song = '<div class="section">';
$chord_list = array();
$transpose = isset($_GET['transpose']) ? intval($_GET['transpose']) : $transpose;
$transpose_accidental = $inkey ? $accidentals[$inkey] : false;
foreach ( explode("\n", $inner) as $line )
{
$chordline = false;
$chords_regex = '/(\((?:[A-G][#b]?(?:[Mm]?7?|2|5|6|add9|sus4|[Mm]aj[79]|dim|aug)?(?:\/[A-G][#b]?)?)\))/';
$line_split = preg_split($chords_regex, $line, -1, PREG_SPLIT_DELIM_CAPTURE);
$line_pattern = '';
if ( preg_match_all($chords_regex, $line, $chords) )
{
// this is a line with lyrics + chords
// echo out the line, adding spans around chords. here is where we also do transposition
// (if requested) and
$line_final = array();
$last_was_chord = false;
foreach ( $line_split as $entry )
{
if ( preg_match($chords_regex, $entry) )
{
if ( $last_was_chord )
{
while ( !($pop = array_pop($line_final)) );
$new_entry = preg_replace('#</span>$#', '', $pop);
$new_entry .= str_repeat(' ', 4);
$new_entry .= prettify_accidentals($chord_list[] = transpose_chord(trim($entry, '()'), $transpose, $transpose_accidental)) . '</span>';
$line_final[] = $new_entry;
}
else
{
$line_final[] = '<span class="halftone-chord">' . prettify_accidentals($chord_list[] = transpose_chord(trim($entry, '()'), $transpose, $transpose_accidental)) . '</span>';
}
$last_was_chord = true;
$line_pattern .= 'c';
}
else
{
if ( trim($entry) != "" )
{
$last_was_chord = false;
$line_final[] = $entry;
$line_pattern .= 'w';
}
}
}
$class_append = preg_match('/^w?c+$/', $line_pattern) ? ' labeled' : '';
$song .= '<span class="halftone-line' . $class_append . '">' . implode("", $line_final) . "</span>\n";
}
else if ( preg_match('/^=\s*(.+?)\s*=$/', $line, $match) )
{
$song .= "</div>\n<div class=\"section\">\n== {$match[1]} ==\n\n";
}
else if ( trim($line) == '' )
{
continue;
}
else if ( preg_match('/^\[(.+)\]$/', trim($line), $match) )
{
$song .= "<br /><strong>Jump to:</strong> {$match[1]}\n";
}
else
{
$song .= "$line<br />\n";
}
}
return $song . '</div>';
}
function page_Special_HalftoneRender()
{
global $accidentals;
$text = isset($_POST['src']) ? base64_decode($_POST['src']) : '';
if ( preg_match('/<halftone(.*?)>(.+?)<\/halftone>/s', $text, $match) )
{
require_once(ENANO_ROOT . '/includes/wikiformat.php');
$carp = new Carpenter();
$carp->exclusive_rule('heading');
$tokey = isset($_GET['tokey']) ? intval($_GET['tokey']) : false;
echo $carp->render(halftone_render_body($match[2], $chord_list, $tokey));
}
}