src/parse/abc_parse.js

//    abc_parse.js: parses a string representing ABC Music Notation into a usable internal structure.

var parseCommon = require('./abc_common');
var parseDirective = require('./abc_parse_directive');
var ParseHeader = require('./abc_parse_header');
var ParseMusic = require('./abc_parse_music');
var Tokenizer = require('./abc_tokenizer');
var wrap = require('./wrap_lines');

var Tune = require('../data/abc_tune');
var TuneBuilder = require('../parse/tune-builder');

var Parse = function() {
	"use strict";
	var tune = new Tune();
	var tuneBuilder = new TuneBuilder(tune);
	var tokenizer;
	var wordsContinuation = '';
	var symbolContinuation = '';

	this.getTune = function() {
		var t = {
			formatting: tune.formatting,
			lines: tune.lines,
			media: tune.media,
			metaText: tune.metaText,
			metaTextInfo: tune.metaTextInfo,
			version: tune.version,

			addElementToEvents: tune.addElementToEvents,
			addUsefulCallbackInfo: tune.addUsefulCallbackInfo,
			getTotalTime: tune.getTotalTime,
			getTotalBeats: tune.getTotalBeats,
			getBarLength: tune.getBarLength,
			getBeatLength: tune.getBeatLength,
			getBeatsPerMeasure: tune.getBeatsPerMeasure,
			getBpm: tune.getBpm,
			getMeter: tune.getMeter,
			getMeterFraction: tune.getMeterFraction,
			getPickupLength: tune.getPickupLength,
			getKeySignature: tune.getKeySignature,
			getElementFromChar: tune.getElementFromChar,
			makeVoicesArray: tune.makeVoicesArray,
			millisecondsPerMeasure: tune.millisecondsPerMeasure,
			setupEvents: tune.setupEvents,
			setTiming: tune.setTiming,
			setUpAudio: tune.setUpAudio,
			deline: tune.deline,
			findSelectableElement: tune.findSelectableElement,
			getSelectableArray: tune.getSelectableArray,
		};
		if (tune.lineBreaks)
			t.lineBreaks = tune.lineBreaks;
		if (tune.visualTranspose)
			t.visualTranspose = tune.visualTranspose;
		return t;
	};

	function addPositioning(el, type, value) {
		if (!el.positioning) el.positioning = {};
		el.positioning[type] = value;
	}

	function addFont(el, type, value) {
		if (!el.fonts) el.fonts = {};
		el.fonts[type] = value;
	}

	var multilineVars = {
		reset: function() {
			for (var property in this) {
				if (this.hasOwnProperty(property) && typeof this[property] !== "function") {
					delete this[property];
				}
			}
			this.iChar = 0;
			this.key = {accidentals: [], root: 'none', acc: '', mode: '' };
			this.meter = null; // if no meter is specified, free meter is assumed
			this.origMeter = null;	// this is for new voices that are created after we set the meter.
			this.hasMainTitle = false;
			this.default_length = 0.125;
			this.clef = { type: 'treble', verticalPos: 0 };
			this.octave = 0;
			this.next_note_duration = 0;
			this.start_new_line = true;
			this.is_in_header = true;
			this.partForNextLine = {};
			this.tempoForNextLine = [];
			this.havent_set_length = true;
			this.voices = {};
			this.staves = [];
			this.macros = {};
			this.currBarNumber = 1;
			this.barCounter = {};
			this.ignoredDecorations = [];
			this.score_is_present = false;	// Can't have original V: lines when there is the score directive
			this.inEnding = false;
			this.inTie = [];
			this.inTieChord = {};
			this.vocalPosition = "auto";
			this.dynamicPosition = "auto";
			this.chordPosition = "auto";
			this.ornamentPosition = "auto";
			this.volumePosition = "auto";
			this.openSlurs = [];
			this.freegchord = false;
			this.endingHoldOver = {};
		},
		differentFont: function(type, defaultFonts) {
			if (this[type].decoration !== defaultFonts[type].decoration) return true;
			if (this[type].face !== defaultFonts[type].face) return true;
			if (this[type].size !== defaultFonts[type].size) return true;
			if (this[type].style !== defaultFonts[type].style) return true;
			if (this[type].weight !== defaultFonts[type].weight) return true;
			return false;
		},
		addFormattingOptions: function(el, defaultFonts, elType) {
			if (elType === 'note') {
				if (this.vocalPosition !== 'auto') addPositioning(el, 'vocalPosition', this.vocalPosition);
				if (this.dynamicPosition !== 'auto') addPositioning(el, 'dynamicPosition', this.dynamicPosition);
				if (this.chordPosition !== 'auto') addPositioning(el, 'chordPosition', this.chordPosition);
				if (this.ornamentPosition !== 'auto') addPositioning(el, 'ornamentPosition', this.ornamentPosition);
				if (this.volumePosition !== 'auto') addPositioning(el, 'volumePosition', this.volumePosition);
				if (this.differentFont("annotationfont", defaultFonts)) addFont(el, 'annotationfont', this.annotationfont);
				if (this.differentFont("gchordfont", defaultFonts)) addFont(el, 'gchordfont', this.gchordfont);
				if (this.differentFont("vocalfont", defaultFonts)) addFont(el, 'vocalfont', this.vocalfont);
				if (this.differentFont("tripletfont", defaultFonts)) addFont(el, 'tripletfont', this.tripletfont);
			} else if (elType === 'bar') {
				if (this.dynamicPosition !== 'auto') addPositioning(el, 'dynamicPosition', this.dynamicPosition);
				if (this.chordPosition !== 'auto') addPositioning(el, 'chordPosition', this.chordPosition);
				if (this.ornamentPosition !== 'auto') addPositioning(el, 'ornamentPosition', this.ornamentPosition);
				if (this.volumePosition !== 'auto') addPositioning(el, 'volumePosition', this.volumePosition);
				if (this.differentFont("measurefont", defaultFonts)) addFont(el, 'measurefont', this.measurefont);
				if (this.differentFont("repeatfont", defaultFonts)) addFont(el, 'repeatfont', this.repeatfont);
			}
		},
		duplicateStartEndingHoldOvers: function() {
			this.endingHoldOver = {
				inTie: [],
				inTieChord: {}
			};
			for (var i = 0; i < this.inTie.length; i++) {
				this.endingHoldOver.inTie.push([]);
				if (this.inTie[i]) { // if a voice is suppressed there might be a gap in the array.
					for (var j = 0; j < this.inTie[i].length; j++) {
						this.endingHoldOver.inTie[i].push(this.inTie[i][j]);
					}
				}
			}
			for (var key in this.inTieChord) {
				if (this.inTieChord.hasOwnProperty(key))
					this.endingHoldOver.inTieChord[key] = this.inTieChord[key];
			}
		},
		restoreStartEndingHoldOvers: function() {
			if (!this.endingHoldOver.inTie)
				return;
			this.inTie = [];
			this.inTieChord = {};
			for (var i = 0; i < this.endingHoldOver.inTie.length; i++) {
				this.inTie.push([]);
				for (var j = 0; j < this.endingHoldOver.inTie[i].length; j++) {
					this.inTie[i].push(this.endingHoldOver.inTie[i][j]);
				}
			}
			for (var key in this.endingHoldOver.inTieChord) {
				if (this.endingHoldOver.inTieChord.hasOwnProperty(key))
					this.inTieChord[key] = this.endingHoldOver.inTieChord[key];
			}
		},
	};

	var addWarning = function(str) {
		if (!multilineVars.warnings)
			multilineVars.warnings = [];
		multilineVars.warnings.push(str);
	};

	var addWarningObject = function(warningObject) {
		if (!multilineVars.warningObjects)
			multilineVars.warningObjects = [];
		multilineVars.warningObjects.push(warningObject);
	};

	var encode = function(str) {
		var ret = str.replace(/\x12/g, ' ');
		ret = ret.replace(/&/g, '&amp;');
		ret = ret.replace(/</g, '&lt;');
		return ret.replace(/>/g, '&gt;');
	};

	var warn = function(str, line, col_num) {
		if (!line) line = " ";
		var bad_char = line[col_num];
		if (bad_char === ' ' || !bad_char)
			bad_char = "SPACE";
		var clean_line = encode(line.substring(col_num - 64, col_num)) + '<span style="text-decoration:underline;font-size:1.3em;font-weight:bold;">' + bad_char + '</span>' + encode(line.substring(col_num + 1).substring(0,64));
		addWarning("Music Line:" + tokenizer.lineIndex + ":" + (col_num+1) + ': ' + str + ":  " + clean_line);
		addWarningObject({message:str, line:line, startChar: multilineVars.iChar + col_num, column: col_num});
	};

	var header;
	var music;

	this.getWarnings = function() {
		return multilineVars.warnings;
	};
	this.getWarningObjects = function() {
		return multilineVars.warningObjects;
	};

	var addWords = function(line, words) {
		if (words.indexOf('\x12') >= 0) {
			wordsContinuation += words
			return
		}
		words = wordsContinuation + words
		wordsContinuation = ''

		if (!line) { warn("Can't add words before the first line of music", line, 0); return; }
		words = parseCommon.strip(words);
		if (words[words.length-1] !== '-')
			words = words + ' ';	// Just makes it easier to parse below, since every word has a divider after it.
		var word_list = [];
		// first make a list of words from the string we are passed. A word is divided on either a space or dash.
		var last_divider = 0;
		var replace = false;
		var addWord = function(i) {
			var word = parseCommon.strip(words.substring(last_divider, i));
			word = word.replace(/\\([-_*|~])/g, '$1')
			last_divider = i+1;
			if (word.length > 0) {
				if (replace)
					word = word.replace(/~/g, ' ');
				var div = words[i];
				if (div !== '_' && div !== '-')
					div = ' ';
				word_list.push({syllable: tokenizer.translateString(word), divider: div});
				replace = false;
				return true;
			}
			return false;
		};
		var escNext = false;
		for (var i = 0; i < words.length; i++) {
			switch (words[i]) {
				case ' ':
				case '\x12':
					addWord(i);
					break;
				case '-':
					if (!escNext && !addWord(i) && word_list.length > 0) {
						parseCommon.last(word_list).divider = '-';
						word_list.push({skip: true, to: 'next'});
					}
					break;
				case '_':
					if (!escNext) {
						addWord(i);
						word_list.push({skip: true, to: 'slur'});
					}
					break;
				case '*':
					if (!escNext) {
						addWord(i);
						word_list.push({skip: true, to: 'next'});
					}
					break;
				case '|':
					if (!escNext) {
						addWord(i);
						word_list.push({skip: true, to: 'bar'});
					}
					break;
				case '~':
					if (!escNext) {
						replace = true;
					}
					break;
			}
			escNext = words[i] === '\\'
		}

		var inSlur = false;
		line.forEach(function(el) {
			if (word_list.length !== 0) {
				if (word_list[0].skip) {
					switch (word_list[0].to) {
						case 'next': if (el.el_type === 'note' && el.pitches !== null && !inSlur) word_list.shift(); break;
						case 'slur': if (el.el_type === 'note' && el.pitches !== null) word_list.shift(); break;
						case 'bar': if (el.el_type === 'bar') word_list.shift(); break;
					}
					if (el.el_type !== 'bar') {
						if (el.lyric === undefined)
							el.lyric = [{syllable: "", divider: " "}];
						else
							el.lyric.push({syllable: "", divider: " "});
					}
				} else {
					if (el.el_type === 'note' && el.rest === undefined && !inSlur) {
						var lyric = word_list.shift();
						if (lyric.syllable)
							lyric.syllable = lyric.syllable.replace(/ +/g,'\xA0');
						if (el.lyric === undefined)
							el.lyric = [ lyric ];
						else
							el.lyric.push(lyric);
					}
				}
			}
		});
	};

	var addSymbols = function(line, words) {
		if (words.indexOf('\x12') >= 0) {
			symbolContinuation += words
			return
		}
		words = symbolContinuation + words
		symbolContinuation = ''

		// TODO-PER: Currently copied from w: line. This needs to be read as symbols instead.
		if (!line) { warn("Can't add symbols before the first line of music", line, 0); return; }
		words = parseCommon.strip(words);
		if (words[words.length-1] !== '-')
			words = words + ' ';	// Just makes it easier to parse below, since every word has a divider after it.
		var word_list = [];
		// first make a list of words from the string we are passed. A word is divided on either a space or dash.
		var last_divider = 0;
		var replace = false;
		var addWord = function(i) {
			var word = parseCommon.strip(words.substring(last_divider, i));
			last_divider = i+1;
			if (word.length > 0) {
				if (replace)
					word = word.replace(/~/g, ' ');
				var div = words[i];
				if (div !== '_' && div !== '-')
					div = ' ';
				word_list.push({syllable: tokenizer.translateString(word), divider: div});
				replace = false;
				return true;
			}
			return false;
		};
		for (var i = 0; i < words.length; i++) {
			switch (words[i]) {
				case ' ':
				case '\x12':
					addWord(i);
					break;
				case '-':
					if (!addWord(i) && word_list.length > 0) {
						parseCommon.last(word_list).divider = '-';
						word_list.push({skip: true, to: 'next'});
					}
					break;
				case '_':
					addWord(i);
					word_list.push({skip: true, to: 'slur'});
					break;
				case '*':
					addWord(i);
					word_list.push({skip: true, to: 'next'});
					break;
				case '|':
					addWord(i);
					word_list.push({skip: true, to: 'bar'});
					break;
				case '~':
					replace = true;
					break;
			}
		}

		var inSlur = false;
		line.forEach(function(el) {
			if (word_list.length !== 0) {
				if (word_list[0].skip) {
					switch (word_list[0].to) {
						case 'next': if (el.el_type === 'note' && el.pitches !== null && !inSlur) word_list.shift(); break;
						case 'slur': if (el.el_type === 'note' && el.pitches !== null) word_list.shift(); break;
						case 'bar': if (el.el_type === 'bar') word_list.shift(); break;
					}
				} else {
					if (el.el_type === 'note' && el.rest === undefined && !inSlur) {
						var lyric = word_list.shift();
						if (el.lyric === undefined)
							el.lyric = [ lyric ];
						else
							el.lyric.push(lyric);
					}
				}
			}
		});
	};

	var parseLine = function(line) {
		if (parseCommon.startsWith(line, '%%')) {
			var err = parseDirective.addDirective(line.substring(2));
			if (err) warn(err, line, 2);
			return;
		}

		var i = line.indexOf('%');
		if (i >= 0)
			line = line.substring(0, i);
		line = line.replace(/\s+$/, '');

		if (line.length === 0)
			return;

		if (wordsContinuation) {
			addWords(tuneBuilder.getCurrentVoice(), line.substring(2));
			return
		}
		if (symbolContinuation) {
			addSymbols(tuneBuilder.getCurrentVoice(), line.substring(2));
			return
		}
		if (line.length < 2 || line[1] !== ':' || music.lineContinuation) {
			music.parseMusic(line);
			return
		}

		var ret = header.parseHeader(line);
		if (ret.regular)
			music.parseMusic(line);
		if (ret.newline)
			music.startNewLine();
		if (ret.words)
			addWords(tuneBuilder.getCurrentVoice(), line.substring(2));
		if (ret.symbols)
			addSymbols(tuneBuilder.getCurrentVoice(), line.substring(2));
	};

	function appendLastMeasure(voice, nextVoice) {
		voice.push({
			el_type: 'hint'
		});
		for (var i = 0; i < nextVoice.length; i++) {
			var element = nextVoice[i];
			var hint = Object.assign({},element);
			voice.push(hint);
			if (element.el_type === 'bar')
					return;
		}
	}

	function addHintMeasure(staff, nextStaff) {
		for (var i = 0; i < staff.length; i++) {
			var stave = staff[i];
			var nextStave = nextStaff[i];
			if (nextStave) { // Be sure there is the same number of staves on the next line.
				for (var j = 0; j < nextStave.voices.length; j++) {
					var nextVoice = nextStave.voices[j];
					var voice = stave.voices[j];
					if (voice) { // Be sure there are the same number of voices on the previous line.
						appendLastMeasure(voice, nextVoice);
					}
				}
			}
		}
	}

	function addHintMeasures() {
		for (var i = 0; i < tune.lines.length; i++) {
			var line = tune.lines[i].staff;
			if (line) {
				var j = i+1;
				while (j < tune.lines.length && tune.lines[j].staff === undefined)
					j++;
				if (j < tune.lines.length) {
					var nextLine = tune.lines[j].staff;
					addHintMeasure(line, nextLine);
				}
			}
		}
	}

	this.parse = function(strTune, switches, startPos) {
		// the switches are optional and cause a difference in the way the tune is parsed.
		// switches.header_only : stop parsing when the header is finished
		// switches.stop_on_warning : stop at the first warning encountered.
		// switches.print: format for the page instead of the browser.
		// switches.format: a hash of the desired formatting commands.
		// switches.hint_measures: put the next measure at the end of the current line.
		// switches.transpose: change the key signature, chords, and notes by a number of half-steps.
		if (!switches) switches = {};
		if (!startPos) startPos = 0;
		tune.reset();

		// Take care of whatever line endings come our way
		// Tack on newline temporarily to make the last line continuation work
		strTune = strTune.replace(/\r\n?/g, '\n') + '\n';

		// get rid of latex commands. If a line starts with a backslash, then it is replaced by spaces to keep the character count the same.
		var arr = strTune.split("\n\\");
		if (arr.length > 1) {
			for (var i2 = 1; i2 < arr.length; i2++) {
				while (arr[i2].length > 0 && arr[i2][0] !== "\n") {
					arr[i2] = arr[i2].substr(1);
					arr[i2-1] += ' ';
				}
			}
			strTune = arr.join("  "); //. the split removed two characters, so this puts them back
		}
		// take care of line continuations right away, but keep the same number of characters
		strTune = strTune.replace(/\\([ \t]*)(%.*)*\n/g, function(all, backslash, comment){
			var padding = comment ? Array(comment.length +1).join(' ') : "";
			return backslash + "\x12" + padding + '\n';
		});
		var lines = strTune.split('\n')
		if (parseCommon.last(lines).length === 0)	// remove the blank line we added above.
			lines.pop();
		tokenizer = new Tokenizer(lines, multilineVars);
		header = new ParseHeader(tokenizer, warn, multilineVars, tune, tuneBuilder);
		music = new ParseMusic(tokenizer, warn, multilineVars, tune, tuneBuilder, header);

		if (switches.print)
			tune.media = 'print';
		multilineVars.reset();
		multilineVars.iChar = startPos;
		if (switches.visualTranspose) {
			multilineVars.globalTranspose = parseInt(switches.visualTranspose);
			if (multilineVars.globalTranspose === 0)
				multilineVars.globalTranspose = undefined;
			else
				tuneBuilder.setVisualTranspose(switches.visualTranspose);
		} else
			multilineVars.globalTranspose = undefined;
		if (switches.lineBreaks) {
			// The line break numbers are 0-based and they reflect the last measure of the current line.
			multilineVars.lineBreaks = switches.lineBreaks;
			//multilineVars.continueall = true;
		}
		header.reset(tokenizer, warn, multilineVars, tune);

		try {
			if (switches.format) {
				parseDirective.globalFormatting(switches.format);
			}
			var line = tokenizer.nextLine();
			while (line) {
				if (switches.header_only && multilineVars.is_in_header === false)
					throw "normal_abort";
				if (switches.stop_on_warning && multilineVars.warnings)
					throw "normal_abort";

				var wasInHeader = multilineVars.is_in_header;
				parseLine(line);
				if (wasInHeader && !multilineVars.is_in_header) {
					tuneBuilder.setRunningFont("annotationfont", multilineVars.annotationfont);
					tuneBuilder.setRunningFont("gchordfont", multilineVars.gchordfont);
					tuneBuilder.setRunningFont("tripletfont", multilineVars.tripletfont);
					tuneBuilder.setRunningFont("vocalfont", multilineVars.vocalfont);
				}
				line = tokenizer.nextLine();
			}

			if (wordsContinuation) {
				addWords(tuneBuilder.getCurrentVoice(), '');
			}
			if (symbolContinuation) {
				addSymbols(tuneBuilder.getCurrentVoice(), '');
			}
			multilineVars.openSlurs = tuneBuilder.cleanUp(multilineVars.barsperstaff, multilineVars.staffnonote, multilineVars.openSlurs);

		} catch (err) {
			if (err !== "normal_abort")
				throw err;
		}

		var ph = 11*72;
		var pl = 8.5*72;
		switch (multilineVars.papersize) {
			//case "letter": ph = 11*72; pl = 8.5*72; break;
			case "legal": ph = 14*72; pl = 8.5*72; break;
			case "A4": ph = 11.7*72; pl = 8.3*72; break;
		}
		if (multilineVars.landscape) {
			var x = ph;
			ph = pl;
			pl = x;
		}
		if (!tune.formatting.pagewidth)
			tune.formatting.pagewidth = pl;
		if (!tune.formatting.pageheight)
			tune.formatting.pageheight = ph;

		if (switches.hint_measures) {
			addHintMeasures();
		}

		wrap.wrapLines(tune, multilineVars.lineBreaks, multilineVars.barNumbers);
	};
};

module.exports = Parse;