background.html

<script type="text/javascript">

var RESET_BLACKLIST_TIME = 1000 * 60 * 20; // in milliseconds, last number is minutes
var RESET_BLACKLIST_TIME = 3000; // For test, 1 second reset

chrome.extension.onRequest.addListener(
    function(request, sender, sendResponse) {
		var loc = request.location;
		var host = loc.host;
		console.log("Processing location: %s", loc.host);

		if (host === "alexbeutel.com" && GETParamFromURL("bewap", loc) === "done") {
			console.log("Matched bewap = done");
			var uid = parseInt(GETParamFromURL("uid", loc));
			// Mark site as recently accessed
			markAsAccessed(uid);
			// Send response to redirect to original site
			sendResponse({
				finishedTask: true,
				destination: getDestFromUID(uid),
				shouldBlock: false
			});
		} else {
			console.log("NOT Matched bewap = done");
			sendResponse({
				shouldBlock: shouldBlock(host,loc.href),
				uid: getUID(host),
				service: localStorage["bewap_service"],
				weight: localStorage["weight:"+host]
			});
		}
    }
);

// Returns a boolean on whether the URL should be blocked.
function shouldBlock(host,url) {
	var s = localStorage["blacklist_sites"].split(" ");
	var found = false;
	for(var j = 0; j < s.length; j++) {
		if(s[j] == host) found=true;
	}
	if(!found) return false;

	var i = 0;
	while (localStorage["blacklist." + i + ".url"] !== undefined) {
		var blacklistURL = localStorage["blacklist." + i + ".url"];
		if (blacklistURL === host) {
			// Returns true if not recently accessed and passed a test
			console.log(url);
			localStorage["blacklist."+i+".dest"] = url;
			return !recentlyAccessed(i);
		}
		i++;
	} 
	console.log(url);
	localStorage["blacklist."+i+".url"] = host;
	localStorage["blacklist."+i+".dest"] = url;
	localStorage["blacklist."+i+".lastAccessed"] = null;
	return !recentlyAccessed(i);
}

// Returns the UID of that host
// returns -1 if none found
function getUID(host) {
	var index = 0;
	var storageKey = _storageURLKey(index);
	while (localStorage[storageKey]) {
		if (localStorage[storageKey] === host) return index;
		index++;
		storageKey = _storageURLKey(index);
	}
	return -1;
}

// Returns a host URL goven the UID
function getHostFromUID(uid) {
	return localStorage[_storageURLKey(uid)];
}

function getDestFromUID(uid) {
	return localStorage[_storageDestKey(uid)];
}

// Returns the String used to store the URL for a given UID
// e.g. "blacklist.0.url"
function _storageURLKey(uid) {
	return "blacklist." + uid + ".url";
}

function _storageDestKey(uid) {
	return "blacklist." + uid + ".dest";
}


function _storageDateKey(uid) {
	return "blacklist." + uid + ".lastAccessed";
}

function recentlyAccessed(index) {
	var lastAccessedTime = localStorage["blacklist." + index + ".lastAccessed"];
	console.log("last accessed time: %s", lastAccessedTime);

	if (lastAccessedTime === null) return false;
	// elapsed in milliseconds
	var elapsed = Date.now() - lastAccessedTime;
	console.log("Recently accessed? %s", elapsed < RESET_BLACKLIST_TIME);
	return elapsed < RESET_BLACKLIST_TIME;
}

// Marks the site as recently accessed
function markAsAccessed(uid) {
	localStorage[_storageDateKey(uid)] = Date.now();
}
    
function GETParamFromURL(param, loc) { 
	var query = loc.search.substring(1); 
	var vars = query.split("&"); 
	for (var i=0; i<vars.length; i++) { 
		var pair = vars[i].split("="); 
		if (pair[0] == param) { 
			console.log("GET Param %s = %s", param, pair[1]);
			return pair[1]; 
		} 
	} 
} 

function trim(stringToTrim) {
	return String(stringToTrim).replace(/^\s+|\s+$/g,"");
}
    
</script>