Отрывок из extension'a для Google Chrome. Diesel Upper

background.js

var requestTimerId;
var pollIntervalMin = 1000 * 60;  // 1 minute
var pollIntervalMax = 1000 * 60 * 60;  // 1 hour
var requestFailureCount = 0;  // used for exponential backoff
var PostMsg = "Dup";

function init() {  
    console.log('Поехали!');
    startRequest();
}

function checkUser() {
    var tUrl = baseUrl;
    var jqxhr = jQuery.ajax({
        dataType: "html",
        url: tUrl
      })
    jqxhr.done( function(data) {    
        var doc = parseData(data);                
        var username = jQuery(doc).find("#userlinks a:first").text();
        var deacc = localStorage.getItem('deacc');        
        return (username == deacc);
    })
    jqxhr.fail( function(error) {
      console.log(error.statusText)
    });
}

function scheduleRequest() {
    if (requestTimerId) {
    window.clearTimeout(requestTimerId);
    }
    var randomness = Math.random() * 2;
    var exponent = Math.pow(2, requestFailureCount);
    var multiplier = Math.max(randomness * exponent, 1);
    var delay = Math.min(multiplier * pollIntervalMin, pollIntervalMax);
    delay = Math.round(delay);
    // var delay = 1000*15;
    requestTimerId = window.setTimeout(startRequest, delay);
}

function startRequest() {    
    handleIcon();
    checkArray();
    scheduleRequest();
}

function handleIcon() {
    var deacc = localStorage.getItem('deacc');
    if (deacc) {        
        chrome.browserAction.setIcon({
            path: "up.png"
        });
        chrome.browserAction.setTitle({
            title: "Добавить Up"
        });
    } else {
        chrome.browserAction.setIcon({
            path: "noactive.png"
        });
        chrome.browserAction.setTitle({
            title: "Укажите логин на diesel"
        });
    }
}

function checkArray() {
    console.log('Проверка данных');
    
    var arr = localStorage.getObject('dup');
    if (!arr) {
        console.log("Нету АПов. Добавьте пожалуйста.")
        return;
    }
    var date = [];
    for (var i = 0, l = arr.length; i < l; i++) {
        date[i] = new Date(arr[i].nextUp);        
        if (Date.now().compareTo(date[i]) == 1 && arr[i].upCount > 0 ) {         
            var tid = arr[i].topicId;            
            Auth(tid);
            break
        }        
    } 
}

function getLS(tid) {    
    var arr = localStorage.getObject('dup');    
    for (var i = 0; i < arr.length; i++) {
        if (tid == arr[i].topicId) {
            return arr[i]            
        }
    }
}

function parseData(data) {
    var parser = new DOMParser();
    var xmlDoc = parser.parseFromString(data,"text/html");
    var body = xmlDoc.getElementsByTagName("body");
    return body;
}

function Auth(tid) {
    var tUrl = topicUrl+tid;
    var jqxhr = jQuery.ajax({
        dataType: "html",
        url: tUrl
      })   
    jqxhr.done( function(data) {    
        var doc = parseData(data);
        var auth_key = jQuery(doc).find("input[name='auth_key']").eq(0).attr('value');                
        var fid = jQuery(doc).find("input[name='f']").attr('value');
        var username = jQuery(doc).find("#userlinks a:first").text();
        var deacc = localStorage.getItem('deacc');        
        if (auth_key !== undefined && username == deacc) {
            requestFailureCount = 0;
            console.log('Тема: #' + tid +' Прошли авторизацию. ');        
            DelPost(fid, tid, auth_key);
        } else {
            console.log('Не авторизованы')
            requestFailureCount++;
        }
    })
    jqxhr.fail( function(error) {
      console.log(error.statusText)
      changeLS({topicId: tid, nextUp: 10})
      requestFailureCount++;
    });
};

function DelPost(fid, tid, auth_key) {
    var pid = getLS(tid).lastMsgId;

    if (pid != 0) {
        var baseData = { act: "Mod", CODE: "04",  f: fid, t: tid, p : pid, auth_key: auth_key};
        var jqxhr = jQuery.ajax({
            type: "GET",
            data: baseData,
            url: baseUrl
            });
        jqxhr.done( function(data) {
            var doc = parseData(data);
            var errortext = $(doc).find('.errorwrap > p').text();
            if (errortext) {
                console.log('Сообщение не удалено.' );
            } else {
                console.log('Сообщение #' + pid + ' удалено');
                requestFailureCount = 0;
            };
            NewPost(fid, tid, auth_key)
          });

        jqxhr.fail( function(err) {
            requestFailureCount++;
            console.log('Сообщение не удалено. По какой-то причине.' );
          });
    } else {
        NewPost(fid, tid, auth_key)
    }  
};

function NewPost(fid, tid, auth_key) {
    var baseData = { act: "Post", CODE: "03", f: fid, t: tid, auth_key: auth_key, Post: PostMsg, enableemo: 'yes'};
    var jqxhr = jQuery.ajax({      
        type: "POST",
        data: baseData,
        dataType: "html",
        url: baseUrl
    })
    jqxhr.done( function(data) {           
        var doc = parseData(data);
        var errortext = $(doc).find('.errorwrap > p').text();
        if (errortext) {            
            requestFailureCount++;
            console.log("Возникла ошибка | ап перенесен на 10 минут");
            changeLS({topicId: tid, nextUp: 10})
        } else {            
            requestFailureCount = 0;
            //<refactor
            //http://diesel.elcat.kg/index.php?showtopic=6713809&view=getlastpost
            var lpid_url = jQuery(doc).find("div[align='right'] > .postdetails:last").children().attr('href');
            var lpid = getParameterByName(lpid_url, 'p');
            //>refactor
            console.log('Новое сообщение создано #' + lpid + '  | ' + Date.now()); 
            changeLS({topicId: tid, lastMsgId: lpid})
        }
    })
    jqxhr.fail( function(err) {
        requestFailureCount++;
        changeLS({topicId: tid, nextUp: 10});
        console.log(err)
    })
};

function changeLS(setup) {
    var n = setup.nextUp || 60;

    var arr = localStorage.getObject('dup');
    var tid = setup.topicId;

    for (var i = 0; i < arr.length; i++) {
        if (tid == arr[i].topicId) {
            arr[i].lastMsgId = setup.lastMsgId || arr[i].lastMsgId;;
            arr[i].nextUp = n.minutes().fromNow();
            if (setup.lastMsgId) {
                arr[i].upCount--;
                console.log('Осталось апов - ' + arr[i].upCount)
            }
        }
    }
  localStorage.setObject('dup', arr);
}

function checkForValidUrl(tabId, changeInfo, tab) {    
    if (tab.url.indexOf(baseUrl) > -1 && getParameterByName(tab.url, "showtopic") != "") {    
        chrome.pageAction.show(tabId);
    }
};



function handlePopup(tabId) {
    var deacc = localStorage.getItem('deacc');
    if (deacc) {
        chrome.browserAction.setPopup({popup: "popup.html"});        
    } else {
        chrome.browserAction.setPopup({popup: ""});
        chrome.tabs.create({
            'url': chrome.extension.getURL('options.html')},
            function(tab) {
            // Tab opened.
        });
    }
}

// Listen for any changes to the URL of any tab.
chrome.tabs.onUpdated.addListener(checkForValidUrl);
// Listen for any changes to the URL of any tab.
chrome.browserAction.onClicked.addListener(handlePopup);

document.addEventListener('DOMContentLoaded', init);