background.js

let page_history_stats = {};  
let current_page_start_time = null; 
let current_page = null; 
let seconds_remaining = null;
let is_started = false;
var counter = null;

function format_url(urls){
    let formatted_urls = []; 
    for(let i=0; i<urls.length; i++){
        formatted_urls.push("*://" + urls[i] + "/*"); 
    }
    console.log(formatted_urls); 
    return formatted_urls; 
}

function block_websites() {
    return {cancel: true};
}


function reset_globals() {
	//TODO: clear intervals
 	page_history_stats = {};  
 	current_page_start_time = null; 
 	current_page = null; 
 	seconds_remaining = null;
 	counter = null;
}

function countdown() {
    seconds_remaining -= 1;
    console.log(seconds_remaining);
    if (seconds_remaining <= 0) {
        clearInterval(counter);
    }
}

function updateCurrentPage(){
	chrome.tabs.query({
		active: true,
		lastFocusedWindow: true
	}, function(tabs) {
		// and use that tab to fill in out title and url
		console.log("tabs: ", tabs); 
		if(tabs.length > 0){
			var tab = tabs[0];
			if(tab.hasOwnProperty('url')){
				current_page = tab.url.split("/")[2]; 
				console.log('updated current_page to ' + current_page);
			}
		}
	});
}

function updateCurrentTime(){
	current_page_start_time = Date.now();
}

function recordPages(){
	let elapsed_time = Math.round((Date.now() - current_page_start_time) / 1000);
	console.log('current_page: ' + current_page);
	console.log('elapsed_time: ' + elapsed_time);
	if (page_history_stats.hasOwnProperty(current_page)) {
		page_history_stats[current_page] += elapsed_time;
	} else {
		page_history_stats[current_page] = elapsed_time;
	}
	updateCurrentTime();
	updateCurrentPage();
	console.log(page_history_stats);
}

chrome.runtime.onMessage.addListener(
    function(request, sender, sendResponse) {
        if (request.task === 'start' && seconds_remaining === null) {
            is_started = true;
            chrome.storage.local.get('blocked_sites', (obj) => {
                chrome.webRequest.onBeforeRequest.addListener(
                    block_websites,
                    {urls: format_url(obj.blocked_sites)},
                    ["blocking"]
                );
            });

			chrome.tabs.onActivated.addListener(
				recordPages
            );
            
			chrome.tabs.onUpdated.addListener(
                recordPages
                // NOTE: we choose multiple triggers over filtering
                // for changeInfo.status == 'complete'
            );

            seconds_remaining = 60;
            // TODO: sync this from main.js
			counter = setInterval(countdown, 1000);
			updateCurrentPage();
			updateCurrentTime(); 

            sendResponse(
                {'seconds_remaining': seconds_remaining}
            );
        } else if (request.task === 'stop') {
            chrome.webRequest.onBeforeRequest.removeListener(block_websites);
        } else if (request.task === 'update_blocked_sites' && seconds_remaining !== null){
            chrome.webRequest.onBeforeRequest.removeListener(block_websites);
            chrome.storage.local.get('blocked_sites', (obj) => {
                chrome.webRequest.onBeforeRequest.addListener(
                    block_websites,
                    {urls: format_url(obj.blocked_sites)},
                    ["blocking"]
                );
            });
        } else if (request.task == 'update_timer') {
            sendResponse(
                {'is_started': is_started,
                 'seconds_remaining': seconds_remaining}
            )
        }
    }
);

chrome.runtime.onInstalled.addListener(
    function() {
        chrome.storage.local.set({'blocked_sites': ['www.youtube.com', 
                                                    'www.netflix.com', 
                                                    'www.reddit.com']},
            function() {
                console.log("set blocked sites successfully");
            }
        );
    }
);