fudi.js

// parse the FUDI networking protocol used by PureData and Max/MSP
// http://wiki.puredata.info/en/FUDI
// usable in any CommonJS environment including in-browser or in node.js
// still requires TCP/UDP JS client/server implementations

var fudi = {
	tokenize: function(string) {
		var tokens = [];
		
		for(var i = 0; i < string.length; i++) {
			var c = string[i];
			
			if(c.match(/\n/)) {
				tokens.push(["whitespace", "\\n"]);
			} else if(c.match(/\t/)) {
				tokens.push(["whitespace", "\\t"]);
			} else if(c.match(/ /)) {
				tokens.push(["whitespace", " "]);
			} else if(c.match(/;/)) {
				tokens.push(["semicolon", c]);
			} else if(c == "\\") {
				tokens.push(["backslash", c]);
			} else {
				tokens.push(["char", c]);
			}
		}
		for(var i = 0; i < tokens.length; i++) {
			if(
				tokens[i][0] == "whitespace" &&
				tokens[i - 1][0] == "backslash"
			) {
				tokens[i][0] = "char";
				tokens.splice(i - 1, 1);
			}
		}
		for(var i = 0; i < tokens.length; void(0)) {
			if(tokens[i][0] == "char") {
				var buffer = "";

				loop:
				for(var j = i; j < tokens.length; j++) {
					if(tokens[j][0] != "char") {
						break loop;
					} else {
						buffer += tokens[j][1];
					}
				}
				tokens[i][0] = "atom", tokens[i][1] = buffer;
				
				tokens.splice(i + 1, j - i - 1);
			} else { i++; }
		}
		return tokens;
	},
	parse: function(string) {
		var tokens = fudi.tokenize(string), messages = [];
		
		for(var i = 0; i < tokens.length; void(0)) {
			if(tokens[i][0] == "atom") {
				var message = [];

				loop:
				for(var j = i; j < tokens.length; j++) {
					if(tokens[j][0] == "atom") {
						message.push(tokens[j][1]);
					} else if(tokens[j][0] == "semicolon") {
						break loop;
					}
				}
				messages.push(message);

				if(i == j) { i++; } else { i = j + 1; }
			} else { i++; }
		}
		return messages;
	}
}
module.exports = fudi;

//console.log(fudi.parse("test/blah 123.45314;"));
//console.log(fudi.parse("my-slider 12;"));
//console.log(fudi.parse("this message continues\nin the following\nline;"))
//console.log(fudi.parse("hello this is a message;"));
//console.log(fudi.parse("you; can; send; multiple messages; in a line;"));
//console.log(fudi.parse("this_atom_contains_a\\\nnewline_character_in_it;"));
//console.log(fudi.parse("this\\ is\\ one\\ whole\\ atom;"));