google_maps_carbon.user.js

// ==UserScript==
// @name           Google Maps Carbon
// @namespace      http://www.amee.com
// @include        http://maps.google.*/
// ==/UserScript==

// Created by James Smith, AMEE - help@amee.cc
// Public domain, do what you like :)

// Once you've installed the greasemonkey script (click "raw" on the top
// right of the gist to do so), you will need to edit it to set the following
// variables correctly:

server = "stage.amee.com"
username = "your_amee_username_here"
password = "your_amee_password_here"
profile_uid = "your_amee_profile_uid_here"

var Base64 = {
	// private property
	_keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
	// public method for encoding
	encode : function (input) {
		var output = "";
		var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
		var i = 0;
		input = Base64._utf8_encode(input);
		while (i < input.length) {
			chr1 = input.charCodeAt(i++);
			chr2 = input.charCodeAt(i++);
			chr3 = input.charCodeAt(i++); 
			enc1 = chr1 >> 2;
			enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
			enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
			enc4 = chr3 & 63;
			if (isNaN(chr2)) {
				enc3 = enc4 = 64;
			} else if (isNaN(chr3)) {
				enc4 = 64;
			} 
			output = output +
			this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
			this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);  
		}
		return output;
	},
	// private method for UTF-8 encoding
	_utf8_encode : function (string) {
		string = string.replace(/\r\n/g,"\n");
		var utftext = "";
		for (var n = 0; n < string.length; n++) {
			var c = string.charCodeAt(n);
			if (c < 128) {
				utftext += String.fromCharCode(c);
			}
			else if((c > 127) && (c < 2048)) {
				utftext += String.fromCharCode((c >> 6) | 192);
				utftext += String.fromCharCode((c & 63) | 128);
			}
			else {
				utftext += String.fromCharCode((c >> 12) | 224);
				utftext += String.fromCharCode(((c >> 6) & 63) | 128);
				utftext += String.fromCharCode((c & 63) | 128);
			}
		} 
		return utftext;
	},
}

function directionsLoaded(event) {
  node = event.relatedNode;
  if ((node.className == "altroute_info") && node.textContent.indexOf('(') == -1) {
    addCO2Value(node);
  }
  if (node.id == "panel4") {
    infonode = document.getElementById("dditd");
    if (infonode.textContent.indexOf('(') == -1) {
      addCO2Value(infonode);
    }
  }
}

function addCO2Value(node) {
  // Get distance out of content
  str = node.textContent;
  str = str.replace("\xA0"," ");
  var distance = str.split(" ");
  // Get co2 data from AMEE 
  gmAjax({
      method: 'GET',
      url: 'http://'+server+'/data/transport/car/generic/drill?size=average&fuel=average',
      headers: {
          'Accept': 'application/json',
          'Authorization':'Basic '+Base64.encode(username+":"+password)
      },
      onload: function(responseDetails) {
          response = JSON.parse(responseDetails.responseText);
          var itemname = (new Date).getTime();
          uid = response['choices']['choices'][0]['value']
            gmAjax({
              method: 'POST',
              url: ('http://'+server+'/profiles/'+profile_uid+'/transport/car/generic') ,
              headers: {
                  'Accept': 'application/json',
                  'Authorization':'Basic '+Base64.encode(username+":"+password),
                  'Content-type':'application/x-www-form-urlencoded'
              },
              data: 'dataItemUid='+uid+'&distance='+distance[0].replace(',','')+'&representation=full&distanceUnit='+distance[1]+'&name='+itemname,
              onload: function(responseDetails) {
                response = JSON.parse(responseDetails.responseText);
                amount = parseFloat(response['profileItems'][0]['amount']['value'])
                node.textContent += " ("+amount.toString()+" kg CO2e)";
              }
          });
      }
  });
}

element = document.getElementById("opanel4");
element.addEventListener("DOMNodeInserted", directionsLoaded, true);

var ajaxQueue = [];
var processAjaxQueue = function(){
  if (ajaxQueue.length > 0) {
    for (ajax in ajaxQueue) {
      var obj = ajaxQueue[ajax];
      GM_xmlhttpRequest(obj);
    }
    ajaxQueue = [];
  }
}
setInterval(function(){
  processAjaxQueue();
}, 100);

function gmAjax(obj){
  ajaxQueue.push(obj);
}