draw-graph.js

function submit() {
	draw_graph();

	// set URL Parameters
	var directed = $("#directed").prop('checked')?'1':'0';
	var ignore = $("#ignore").prop('checked')?'1':'0';
	var data = $("#data").val();
	var url = location.pathname+"?"+"data="+encodeURIComponent(data).replace(/%20/g,'+')+"&directed="+directed+"&ignore="+ignore;
	window.history.replaceState("","",url);
}

function draw_graph() {
	var directed = $("#directed").prop('checked');
	var ignore = $("#ignore").prop('checked');

	var data = $("#data").val();
	data = data.split('\n');
	if (ignore && data.length >= 1) {
		data[0] = "";
	}
	for (var i in data) {
		data[i] = data[i].trim().split(/ +/);
		if (data[i].length >= 2) {
			data[i][0] = data[i][0];
			data[i][1] = data[i][1];
		}
	}

	//create nodes
	var nodes_set = new Set();
	for (var i in data) {
		if (data[i].length < 2) continue;
		nodes_set.add(data[i][0]);
		nodes_set.add(data[i][1]);
	}
	var nodes = [];
	for (var node of nodes_set) {
		nodes.push({id: node, label: node});
	}

	// create edges
	var edges = [];
	for (var i in data) {
		if (data[i].length < 2) continue;
		var edge = {from: data[i][0], to: data[i][1]};
		if (data[i].length >= 3) {
			edge.label = data[i][2];
		}
		if (directed) {
			edge.arrows = 'to';
		}
		edges.push(edge);
	}

	// create a network
	var container = document.getElementById('graph');
	var data = {
		nodes: new vis.DataSet(nodes),
		edges: new vis.DataSet(edges)
	};
	var options = {};
	var network = new vis.Network(container, data, options);
}

$(document).ready(function() {
	// load URL Parameters
	if (getUrlParameter("ignore")) {
		$("#ignore").prop('checked',getUrlParameter("ignore")=="1");
	}
	if (getUrlParameter("directed")) {
		$("#directed").prop('checked',getUrlParameter("directed")=="1");
	}
	if (getUrlParameter("data")) {
		$("#data").val(getUrlParameter("data"));
		draw_graph();
	}

	// Ctrl / Cmd + Enter
	$("#data").keydown(function(e) {
		if ((e.ctrlKey || e.metaKey) && e.keyCode == 13) {
			submit();
		}
	});
});

var getUrlParameter = function getUrlParameter(sParam) {
	var sPageURL = decodeURIComponent(window.location.search.substring(1).replace(/\+/g, '%20'));
	var sURLVariables = sPageURL.split('&');

	for (var i = 0; i < sURLVariables.length; i++) {
		var sParameterName = sURLVariables[i].split('=');

		if (sParameterName[0] === sParam) {
			return sParameterName[1] === undefined ? true : sParameterName[1];
		}
	}
};