var Engine = {
    Debug: true,
        
    //Clickable objects
    Clickables: {        
        //Main menu buttons
        terminalMainMenuButton:         null,
        characterMainMenuButton:        null,
        scriptEditorMainMenuButton:     null,
        activeScriptsMainMenuButton:    null,
        hacknetNodesMainMenuButton:     null,
        worldMainMenuButton:            null,
        createProgramMainMenuButton:    null,
        factionsMainMenuButton:         null,
        augmentationsMainMenuButton:    null,
        tutorialMainMenuButton:         null,
        saveMainMenuButton:             null,
        deleteMainMenuButton:           null,
        
        //Tutorial buttons
        tutorialGettingStartedButton:   null,
        tutorialNetworkingButton:       null,
        tutorialHackingButton:          null,
        tutorialScriptsButton:          null,
        tutorialNetscriptButton:        null,
        tutorialTravelingButton:        null,
        tutorialJobsButton:             null,
        tutorialFactionsButton:         null,
        tutorialAugmentationsButton:    null,
        tutorialBackButton:             null,
    },
    
    //Display objects
    Display: {
        //Progress bar
        progress:               null,
        
        //Display for status text (such as "Saved" or "Loaded")
        statusText:             null,
        
        hacking_skill:          null,
        
        //Main menu content
        terminalContent:                null,
        characterContent:               null,
        scriptEditorContent:            null,
        activeScriptsContent:           null,
        hacknetNodesContent:            null,
        worldContent:                   null,
        createProgramContent:           null,
        factionsContent:                null,
        factionContent:                 null,
        factionAugmentationsContent:    null,
        augmentationsContent:           null,
        tutorialContent:                null,
        locationContent:                null,
        workInProgressContent:          null,
        
        //Character info
        characterInfo:                  null,
        
        //Script editor text
        scriptEditorText:               null,
    },
    
    //Current page status 
    Page: {
        Terminal:           "Terminal",
        CharacterInfo:      "CharacterInfo",
        ScriptEditor:       "ScriptEditor",
        ActiveScripts:      "ActiveScripts",
        HacknetNodes:       "HacknetNodes",
        World:              "World",
        CreateProgram:      "CreateProgram",
        Factions:           "Factions",
        Faction:            "Faction",
        Augmentations:      "Augmentations",
        Tutorial:           "Tutorial",
        Location:           "Location",
        workInProgress:     "WorkInProgress",
    },
    currentPage:    null,

    
    //Time variables (milliseconds unix epoch time)
    _lastUpdate: new Date().getTime(),
    _idleSpeed: 200,    //Speed (in ms) at which the main loop is updated
    
    
    /* Load content when a main menu button is clicked */ 
    loadTerminalContent: function() {
        Engine.hideAllContent();
        Engine.Display.terminalContent.style.visibility = "visible";
        Engine.currentPage = Engine.Page.Terminal;
    },
    
    loadCharacterContent: function() {
        Engine.hideAllContent();
        Engine.Display.characterContent.style.visibility = "visible";
        Engine.displayCharacterInfo();
        Engine.currentPage = Engine.Page.CharacterInfo;
    },
    
    loadScriptEditorContent: function(filename = "", code = "") {
        Engine.hideAllContent();
        Engine.Display.scriptEditorContent.style.visibility = "visible";
        if (filename == "") {
            document.getElementById("script-editor-filename").value = "untitled";
        } else {
            document.getElementById("script-editor-filename").value = filename;
        }
        document.getElementById("script-editor-text").value = code;
        
        Engine.currentPage = Engine.Page.ScriptEditor;
    },
    
    loadActiveScriptsContent: function() {
        Engine.hideAllContent();
        Engine.Display.activeScriptsContent.style.visibility = "visible";
        
        Engine.currentPage = Engine.Page.ActiveScripts;
    },
    
    loadHacknetNodesContent: function() {
        Engine.hideAllContent();
        Engine.Display.hacknetNodesContent.style.visibility = "visible";
        displayHacknetNodesContent();
        
        Engine.currentPage = Engine.Page.HacknetNodes;
    },
    
    loadWorldContent: function() {
        Engine.hideAllContent();
        Engine.Display.worldContent.style.visibility = "visible";
        Engine.displayWorldInfo();
        
        Engine.currentPage = Engine.Page.World;
    },
    
    loadCreateProgramContent: function() {
        Engine.hideAllContent();
        Engine.Display.createProgramContent.style.visibility = "visible";
        displayCreateProgramContent();
        
        Engine.currentPage = Engine.Page.CreateProgram;
    },
    
    loadFactionsContent: function() {
        Engine.hideAllContent();
        Engine.Display.factionsContent.style.visibility = "visible";
        Engine.displayFactionsInfo();
        
        Engine.currentPage = Engine.Page.Factions;
    },
    
    loadFactionContent: function() {
        Engine.hideAllContent();
        Engine.Display.factionContent.style.visibility = "visible";
        
        Engine.currentPage = Engine.Page.Faction;
    },
    
    loadAugmentationsContent: function() {
        Engine.hideAllContent();
        Engine.Display.augmentationsContent.style.visibility = "visible";
        Engine.displayAugmentationsContent();
        
        Engine.currentPage = Engine.Page.Augmentations;
    },
    
    loadTutorialContent: function() {
        Engine.hideAllContent();
        Engine.Display.tutorialContent.style.visibility = "visible";
        Engine.displayTutorialContent();
        
        Engine.currentPage = Engine.Page.Tutorial;
    },
    
    loadLocationContent: function() {
        Engine.hideAllContent();
        Engine.Display.locationContent.style.visibility = "visible";
        displayLocationContent();
        
        Engine.currentPage = Engine.Page.Location;
    },
    
    loadWorkInProgressContent: function() {
        Engine.hideAllContent();
        
        var mainMenu = document.getElementById("mainmenu-container");
        mainMenu.style.visibility = "hidden";
        
        Engine.Display.workInProgressContent.style.visibility = "visible";
        
        Engine.currentPage = Engine.Page.WorkInProgress;
    },
    
    //Helper function that hides all content 
    hideAllContent: function() {
        Engine.Display.terminalContent.style.visibility = "hidden";
        Engine.Display.characterContent.style.visibility = "hidden";
        Engine.Display.scriptEditorContent.style.visibility = "hidden";
        Engine.Display.activeScriptsContent.style.visibility = "hidden";
        Engine.Display.hacknetNodesContent.style.visibility = "hidden";
        Engine.Display.worldContent.style.visibility = "hidden";
        Engine.Display.createProgramContent.style.visibility = "hidden";
        Engine.Display.factionsContent.style.visibility = "hidden";
        Engine.Display.factionContent.style.visibility = "hidden";
        Engine.Display.factionAugmentationsContent.style.visibility = "hidden";
        Engine.Display.augmentationsContent.style.visibility = "hidden";
        Engine.Display.tutorialContent.style.visibility = "hidden";
        Engine.Display.locationContent.style.visibility = "hidden";
        Engine.Display.workInProgressContent.style.visibility = "hidden";
        
        //Location lists
        Engine.aevumLocationsList.style.display = "none";
        Engine.chongqingLocationsList.style.display = "none";
        Engine.sector12LocationsList.style.display = "none";
        Engine.newTokyoLocationsList.style.display = "none";
        Engine.ishimaLocationsList.style.display = "none";
        Engine.volhavenLocationsList.style.display = "none";
    },
    
    /* Display character info */
    displayCharacterInfo: function() {
        var companyPosition = "";
        if (Player.companyPosition != "") {
            companyPosition = Player.companyPosition.positionName;
        }
        Engine.Display.characterInfo.innerHTML = 
       ('<b>General</b><br><br>' + 
        'Current City: ' + Player.city + '<br><br>' + 
        'Employer: ' + Player.companyName + '<br>' + 
        'Job Title: ' + companyPosition + '<br><br>' + 
        'Money: $' + formatNumber(Player.money, 2)+ '<br><br><br>' +
        '<b>Stats</b><br><br>' + 
        'Hacking Level: ' + (Player.hacking_skill).toLocaleString() + 
                        " (" + formatNumber(Player.hacking_exp, 4) + ' experience)<br>' + 
        'Strength:      ' + (Player.strength).toLocaleString() + 
                   " (" + formatNumber(Player.strength_exp, 4) + ' experience)<br>' + 
        'Defense:       ' + (Player.defense).toLocaleString() + 
                  " (" + formatNumber(Player.defense_exp, 4) + ' experience)<br>' + 
        'Dexterity:     ' + (Player.dexterity).toLocaleString() + 
                   " (" + formatNumber(Player.dexterity_exp, 4) + ' experience)<br>' + 
        'Agility:       ' + (Player.agility).toLocaleString() + 
                  " (" + formatNumber(Player.agility_exp, 4) + ' experience)<br>' +
        'Charisma:      ' + (Player.charisma).toLocaleString() +
                   " (" + formatNumber(Player.charisma_exp, 4) + ' experience)<br><br><br>' +
        '<b>Multipliers</b><br><br>' + 
        'Hacking Chance multiplier: ' + formatNumber(Player.hacking_chance_mult * 100, 2) + '%<br>' + 
        'Hacking Speed multiplier:  ' + formatNumber(Player.hacking_speed_mult * 100, 2) + '%<br>' + 
        'Hacking money multiplier:  ' + formatNumber(Player.hacking_money_mult * 100, 2) + '%<br><br>' + 
        'Hacking Level multiplier:      ' + formatNumber(Player.hacking_mult * 100, 2) + '%<br>' +
        'Hacking Experience multiplier: ' + formatNumber(Player.hacking_exp_mult * 100, 2) + '%<br><br>' + 
        'Strength Level multiplier:      ' + formatNumber(Player.strength_mult * 100, 2) + '%<br>' + 
        'Strength Experience multiplier: ' + formatNumber(Player.strength_exp_mult * 100, 2) + '%<br><br>' + 
        'Defense Level multiplier:      ' + formatNumber(Player.defense_mult * 100, 2) + '%<br>' + 
        'Defense Experience multiplier: ' + formatNumber(Player.defense_exp_mult * 100, 2) + '%<br><br>' + 
        'Dexterity Level multiplier:      ' + formatNumber(Player.dexterity_mult * 100, 2) + '%<br>' + 
        'Dexterity Experience multiplier: ' + formatNumber(Player.dexterity_exp_mult * 100, 2) + '%<br><br>' + 
        'Agility Level multiplier:      ' + formatNumber(Player.agility_mult * 100, 2) + '%<br>' + 
        'Agility Experience multiplier: ' + formatNumber(Player.agility_exp_mult * 100, 2) + '%<br><br>' + 
        'Charisma Level multiplier:      ' + formatNumber(Player.charisma_mult * 100, 2) + '%<br>' + 
        'Charisma Experience multiplier: ' + formatNumber(Player.charisma_exp_mult * 100, 2) + '%<br><br>' + 
        'Hacknet Node production multiplier:         ' + formatNumber(Player.hacknet_node_money_mult * 100, 2) + '%<br>' +
        'Hacknet Node purchase cost multiplier:      ' + formatNumber(Player.hacknet_node_purchase_cost_mult * 100, 2) + '%<br>' +
        'Hacknet Node RAM upgrade cost multiplier:   ' + formatNumber(Player.hacknet_node_ram_cost_mult * 100, 2) + '%<br>' + 
        'Hacknet Node Core purchase cost multiplier: ' + formatNumber(Player.hacknet_node_core_cost_mult * 100, 2) + '%<br>' + 
        'Hacknet Node level upgrade cost multiplier: ' + formatNumber(Player.hacknet_node_level_cost_mult * 100, 2) + '%<br><br>' + 
        'Company reputation gain multiplier: ' + formatNumber(Player.company_rep_mult * 100, 2) + '%<br>' + 
        'Faction reputation gain multiplier: ' + formatNumber(Player.faction_rep_mult * 100, 2) + '%<br>' + 
        'Salary multiplier: ' + formatNumber(Player.work_money_mult * 100, 2) + '%<br>' + 
        'Crime money multiplier: ' + formatNumber(Player.crime_money_mult * 100, 2) + '%<br><br><br>' +
        '<b>Misc</b><br><br>' + 
        'Servers owned:       ' + Player.purchasedServers.length + '<br>' + 
        'Hacknet Nodes owned: ' + Player.hacknetNodes.length + '<br><br> ').replace( / /g, "&nbsp;" );
        
    },
    
    /* Display locations in the world*/
    aevumLocationsList:        null,
    chongqingLocationsList:    null,
    sector12LocationsList:     null, 
    newTokyoLocationsList:     null,
    ishimaLocationsList:       null,
    volhavenLocationsList:     null,
    
    displayWorldInfo: function() {
        Engine.aevumLocationsList.style.display = "none";
        Engine.chongqingLocationsList.style.display = "none";
        Engine.sector12LocationsList.style.display = "none";
        Engine.newTokyoLocationsList.style.display = "none";
        Engine.ishimaLocationsList.style.display = "none";
        Engine.volhavenLocationsList.style.display = "none";
        
        document.getElementById("world-city-name").innerHTML = Player.city;
        var cityDesc = document.getElementById("world-city-desc"); //TODO
        switch(Player.city) {

            case Locations.Aevum:
                Engine.aevumLocationsList.style.display = "inline";
                break;
            case Locations.Chongqing:
                Engine.chongqingLocationsList.style.display = "inline";
                break;
            case Locations.Sector12:
                Engine.sector12LocationsList.style.display = "inline";
                break;
            case Locations.NewTokyo:
                Engine.newTokyoLocationsList.style.display = "inline";
                break;
            case Locations.Ishima:
                Engine.ishimaLocationsList.style.display = "inline";
                break;
            case Locations.Volhaven:
                Engine.volhavenLocationsList.style.display = "inline";
                break;
            default:
                console.log("Invalid city value in Player object!");
                break;
        }
    },
    
    /* Functions used to update information on the Active Scripts page */
    ActiveScriptsList:             null,
    
    //Creates and adds the <li> object for a given workerScript
    addActiveScriptsItem: function(workerscript) {
        var item = document.createElement("li");
        
        Engine.createActiveScriptsText(workerscript, item);
        
        //Add the li element onto the list
        if (Engine.ActiveScriptsList == null) {
            Engine.ActiveScriptsList = document.getElementById("active-scripts-list");
        }
        Engine.ActiveScriptsList.appendChild(item);
    },
    
    deleteActiveScriptsItem: function(i) {
        var list = Engine.ActiveScriptsList.querySelectorAll('#active-scripts-list li');
        if (i >= list.length) {
            throw new Error("Trying to delete an out-of-range Active Scripts item");
        }
        
        var li = list[i];
        li.parentNode.removeChild(li);
    },
    
    //Update the ActiveScriptsItems array
    updateActiveScriptsItems: function() {
        for (var i = 0; i < workerScripts.length; ++i) {
            Engine.updateActiveScriptsItemContent(i, workerScripts[i]);
        }
    },
    
    //Updates the content of the given item in the Active Scripts list
    updateActiveScriptsItemContent: function(i, workerscript) {
        var list = Engine.ActiveScriptsList.getElementsByTagName("li");
        if (i >= list.length) {
            throw new Error("Trying to update an out-of-range Active Scripts Item");
        }
        
        var item = list[i];
        
        //Clear the item
        while (item.firstChild) {
            item.removeChild(item.firstChild);
        }
        
        //Add the updated text back
        Engine.createActiveScriptsText(workerscript, item);
    },
    
    createActiveScriptsText: function(workerscript, item) {
        //Script name
        var scriptName = document.createElement("h2");
        scriptName.appendChild(document.createTextNode(workerscript.name));
        item.appendChild(scriptName);
        
        var itemText = document.createElement("p");
        
        //Server ip/hostname
        var hostname = workerscript.getServer().hostname;
        var serverIpHostname = "Server: " + hostname + "(" + workerscript.serverIp + ")";
        
        //Online
        var onlineTotalMoneyMade = "Total online production: $" + formatNumber(workerscript.scriptRef.onlineMoneyMade, 2);
        var onlineTotalExpEarned = (Array(26).join(" ") + formatNumber(workerscript.scriptRef.onlineExpGained, 2) + " hacking exp").replace( / /g, "&nbsp;");
        
        var onlineMps = workerscript.scriptRef.onlineMoneyMade / workerscript.scriptRef.onlineRunningTime;
        var onlineMpsText = "Online production rate: $" + formatNumber(onlineMps, 2) + "/second";
        var onlineEps = workerscript.scriptRef.onlineExpGained / workerscript.scriptRef.onlineRunningTime;
        var onlineEpsText = (Array(25).join(" ") + formatNumber(onlineEps, 4) + " hacking exp/second").replace( / /g, "&nbsp;");
        
        //Offline
        var offlineTotalMoneyMade = "Total offline production: $" + formatNumber(workerscript.scriptRef.offlineMoneyMade, 2);
        var offlineTotalExpEarned = (Array(27).join(" ") + formatNumber(workerscript.scriptRef.offlineExpGained, 2) + " hacking exp").replace( / /g, "&nbsp;");
        
        var offlineMps = workerscript.scriptRef.offlineMoneyMade / workerscript.scriptRef.offlineRunningTime;
        var offlineMpsText = "Offline production rate: $" + formatNumber(offlineMps, 2) + "/second";
        var offlineEps = workerscript.scriptRef.offlineExpGained / workerscript.scriptRef.offlineRunningTime;
        var offlineEpsText = (Array(26).join(" ") + formatNumber(offlineEps, 4) +  " hacking exp/second").replace( / /g, "&nbsp;");
        
        itemText.innerHTML = serverIpHostname + "<br>" + onlineTotalMoneyMade + "<br>" + onlineTotalExpEarned + "<br>" +
                             onlineMpsText + "<br>" + onlineEpsText + "<br>" + offlineTotalMoneyMade + "<br>" + offlineTotalExpEarned + "<br>" +
                             offlineMpsText + "<br>" + offlineEpsText + "<br>";
        
        item.appendChild(itemText);
    },
    
    displayFactionsInfo: function() {
        var factionsList = document.getElementById("factions-list");
        
        //Clear the list 
        while (factionsList.firstChild) {
            factionsList.removeChild(factionsList.firstChild);
        }
        
        //Re-add a link for each faction you are a member of
        for (var i = 0; i < Player.factions.length; ++i) {
            (function () {
                var factionName = Player.factions[i];
                
                //Add the faction to the Factions page content
                var item = document.createElement("li");
                var aElem = document.createElement("a");
                aElem.setAttribute("href", "#");
                aElem.setAttribute("class", "a-link-button");
                aElem.innerHTML = factionName;
                aElem.addEventListener("click", function() {
                    console.log("factionName:" + factionName)
                    Engine.loadFactionContent();
                    displayFactionContent(factionName);
                    return false;
                });
                item.appendChild(aElem);
                                
                factionsList.appendChild(item);                
            }()); //Immediate invocation
        }
    },
    
    displayAugmentationsContent: function() {
        var augmentationsList = document.getElementById("augmentations-list");
        
        while (augmentationsList.firstChild) {
            augmentationsList.removeChild(augmentationsList.firstChild);
        }
        
        for (var i = 0; i < Player.augmentations.length; ++i) {
            var augName = Player.augmentations[i];
            var aug = Augmentations[augName];
            
            
            var item = document.createElement("li");
            var hElem = document.createElement("h2");
            var pElem = document.createElement("p");
            
            item.setAttribute("class", "installed-augmentation");
            hElem.innerHTML = augName;
            if (augName == AugmentationNames.NeuroFluxGovernor) {
                hElem.innerHTML += " - Level " + (aug.level);
            }
            pElem.innerHTML = aug.info;
            
            item.appendChild(hElem);
            item.appendChild(pElem);
            
            augmentationsList.appendChild(item);
        }
    },
    
    displayTutorialContent: function() {
        Engine.Clickables.tutorialGettingStartedButton.style.display = "block";
        Engine.Clickables.tutorialNetworkingButton.style.display = "block";
        Engine.Clickables.tutorialHackingButton.style.display = "block";
        Engine.Clickables.tutorialScriptsButton.style.display = "block";
        Engine.Clickables.tutorialNetscriptButton.style.display = "block";
        Engine.Clickables.tutorialTravelingButton.style.display = "block";
        Engine.Clickables.tutorialJobsButton.style.display = "block";
        Engine.Clickables.tutorialFactionsButton.style.display = "block";
        Engine.Clickables.tutorialAugmentationsButton.style.display = "block";    

        Engine.Clickables.tutorialBackButton.style.display = "none";
        document.getElementById("tutorial-text").style.display = "none";
    },
    
    //Displays the text when a section of the Tutorial is opened
    displayTutorialPage: function(text) {
        Engine.Clickables.tutorialGettingStartedButton.style.display = "none";
        Engine.Clickables.tutorialNetworkingButton.style.display = "none";
        Engine.Clickables.tutorialHackingButton.style.display = "none";
        Engine.Clickables.tutorialScriptsButton.style.display = "none";
        Engine.Clickables.tutorialNetscriptButton.style.display = "none";
        Engine.Clickables.tutorialTravelingButton.style.display = "none";
        Engine.Clickables.tutorialJobsButton.style.display = "none";
        Engine.Clickables.tutorialFactionsButton.style.display = "none";
        Engine.Clickables.tutorialAugmentationsButton.style.display = "none";
        
        Engine.Clickables.tutorialBackButton.style.display = "inline-block";
        document.getElementById("tutorial-text").style.display = "block";
        document.getElementById("tutorial-text").innerHTML = text;
    },
    
    /* Main Event Loop */
    idleTimer: function() {
        //Get time difference
        var _thisUpdate = new Date().getTime();
        var diff = _thisUpdate - Engine._lastUpdate;
        var offset = diff % Engine._idleSpeed;
        
        //Divide this by cycle time to determine how many cycles have elapsed since last update
        diff = Math.floor(diff / Engine._idleSpeed);
                
        if (diff > 0) {
            //Update the game engine by the calculated number of cycles
            Engine.updateGame(diff);
            Engine._lastUpdate = _thisUpdate - offset;
            Player.lastUpdate = _thisUpdate - offset;
        }       
        
        window.requestAnimationFrame(Engine.idleTimer);
    },
    
    updateGame: function(numCycles = 1) {
        //Start Manual hack 
        if (Player.startAction == true) {
            Engine._totalActionTime = Player.actionTime;
            Engine._actionTimeLeft = Player.actionTime;
            Engine._actionInProgress = true;
            Engine._actionProgressBarCount = 1;
            Engine._actionProgressStr = "[                                                  ]";
            Engine._actionTimeStr = "Time left: ";
            Player.startAction = false;
        }
        
        //Working
        if (Player.isWorking) {
            if (Player.workType == CONSTANTS.WorkTypeFaction) {
                Player.workForFaction(numCycles);
            } else if (Player.workType == CONSTANTS.WorkTypeCreateProgram) {
                Player.createProgramWork(numCycles);
            } else if (Player.workType == CONSTANTS.WorkTypeStudyClass) {
                Player.takeClass(numCycles);  
            } else if (Player.workType == CONSTANTS.WorkTypeCrime) {
                Player.commitCrime(numCycles);
            } else if (Player.workType == CONSTANTS.WorkTypeCompanyPartTime) {
                Player.workPartTime(numCycles);
            } else {
                Player.work(numCycles);
            }
        }
        
        //Counters
        Engine.decrementAllCounters(numCycles);
        Engine.checkCounters();        
        
        //Manual hacks
        if (Engine._actionInProgress == true) {
            Engine.updateHackProgress(numCycles);
        }
        
        //Update the running time of all active scripts
        updateOnlineScriptTimes(numCycles);
        
        //Hacknet Nodes
        processAllHacknetNodeEarnings(numCycles);
    },
    
    //Counters for the main event loop. Represent the number of game cycles are required
    //for something to happen. 
    Counters: {
        autoSaveCounter:    300,            //Autosave every minute
        updateSkillLevelsCounter: 10,       //Only update skill levels every 2 seconds. Might improve performance
        updateDisplays: 3,                  //Update displays such as Active Scripts display and character display
        createProgramNotifications: 10,     //Checks whether any programs can be created and notifies
        serverGrowth: 450,                  //Process server growth every minute and a half
        checkFactionInvitations: 1500,      //Check whether you qualify for any faction invitations every 5 minutes
        passiveFactionGrowth: 600,
    },
    
    decrementAllCounters: function(numCycles = 1) {
        for (var counter in Engine.Counters) {
            if (Engine.Counters.hasOwnProperty(counter)) {
                Engine.Counters[counter] = Engine.Counters[counter] - numCycles;
            }
        }
    },
    
    //Checks if any counters are 0 and if they are, executes whatever
    //is necessary and then resets the counter
    checkCounters: function() {
        if (Engine.Counters.autoSaveCounter <= 0) {
            saveObject.saveGame();
            Engine.Counters.autoSaveCounter = 300;
        }
        
        if (Engine.Counters.updateSkillLevelsCounter <= 0) {
            Player.updateSkillLevels();
            Engine.Counters.updateSkillLevelsCounter = 10;
        }
        
        if (Engine.Counters.updateDisplays <= 0) {
            if (Engine.currentPage == Engine.Page.ActiveScripts) {
                Engine.updateActiveScriptsItems();
            } else if (Engine.currentPage == Engine.Page.CharacterInfo) {
                Engine.displayCharacterInfo();
            }  else if (Engine.currentPage == Engine.Page.HacknetNodes) {
                updateHacknetNodesContent();
            } else if (Engine.currentPage == Engine.Page.CreateProgram) {
                displayCreateProgramContent();
            }
            
            Engine.Counters.updateDisplays = 3;
        }
        
        if (Engine.Counters.createProgramNotifications <= 0) {
            var num = getNumAvailableCreateProgram();
            var elem = document.getElementById("create-program-notification");
            if (num > 0) {
                elem.innerHTML = num;
                elem.setAttribute("class", "notification-on");
            } else {
                elem.innerHTML = "";
                elem.setAttribute("class", "notification-off");
            }
            Engine.Counters.createProgramNotifications = 10;
        }
        
        if (Engine.Counters.serverGrowth <= 0) {
            var numCycles = Math.floor((450 - Engine.Counters.serverGrowth));
            processServerGrowth(numCycles);
            Engine.Counters.serverGrowth = 450;
        }
        
        if (Engine.Counters.checkFactionInvitations <= 0) {
            var invitedFactions = Player.checkForFactionInvitations();
            if (invitedFactions.length > 0) {
                var randFaction = invitedFactions[Math.floor(Math.random() * invitedFactions.length)];
                inviteToFaction(randFaction);
            }
            Engine.Counters.checkFactionInvitations = 1500;
        }
        
        if (Engine.Counters.passiveFactionGrowth <= 0) {
            var adjustedCycles = Math.floor((600 - Engine.Counters.passiveFactionGrowth));
            processPassiveFactionRepGain(adjustedCycles);
            Engine.Counters.passiveFactionGrowth = 600;
        }
    },
    
    /* Calculates the hack progress for a manual (non-scripted) hack and updates the progress bar/time accordingly */
    _totalActionTime: 0,
    _actionTimeLeft: 0,
    _actionTimeStr: "Time left: ",
    _actionProgressStr: "[                                                  ]",
    _actionProgressBarCount: 1,
    _actionInProgress: false,
    updateHackProgress: function(numCycles = 1) {
        var timeElapsedMilli = numCycles * Engine._idleSpeed;
        Engine._actionTimeLeft -= (timeElapsedMilli/ 1000);    //Substract idle speed (ms)
        Engine._actionTimeLeft = Math.max(Engine._actionTimeLeft, 0);
    
        //Calculate percent filled 
        var percent = Math.round((1 - Engine._actionTimeLeft / Engine._totalActionTime) * 100);
        
        //Update progress bar 
        while (Engine._actionProgressBarCount * 2 <= percent) {
            Engine._actionProgressStr = Engine._actionProgressStr.replaceAt(Engine._actionProgressBarCount, "|");
            Engine._actionProgressBarCount += 1;
        }
        
        //Update hack time remaining
        Engine._actionTimeStr = "Time left: " + Math.max(0, Math.round(Engine._actionTimeLeft)).toString() + "s";
        document.getElementById("hack-progress").innerHTML = Engine._actionTimeStr;
        
        //Dynamically update progress bar
        document.getElementById("hack-progress-bar").innerHTML = Engine._actionProgressStr.replace( / /g, "&nbsp;" );
        
        //Once percent is 100, the hack is completed
        if (percent >= 100) {
            Engine._actionInProgress = false;
            Terminal.finishAction();
        }
    },
    
    load: function() {
        //Load game from save or create new game
        if (loadGame(saveObject)) {    
            console.log("Loaded game from save");
            Engine.setDisplayElements();    //Sets variables for important DOM elements
            Engine.init();                  //Initialize buttons, work, etc.
            Engine.start();                 //Run main game loop and Scripts loop
            CompanyPositions.init();

            //Calculate the number of cycles have elapsed while offline
            var thisUpdate = new Date().getTime();
            var lastUpdate = Player.lastUpdate;
            var numCyclesOffline = Math.floor((thisUpdate - lastUpdate) / Engine._idleSpeed);
            
            /* Process offline progress */
            processServerGrowth(numCyclesOffline);    //Should be done before offline production for scripts
            loadAllRunningScripts();    //This also takes care of offline production for those scripts
            if (Player.isWorking) {
                if (Player.workType == CONSTANTS.WorkTypeFaction) {
                    Player.workForFaction(numCyclesOffline);
                } else if (Player.workType == CONSTANTS.WorkTypeCreateProgram) {
                    Player.createProgramWork(numCyclesOffline);
                } else if (Player.workType == CONSTANTS.WorkTypeStudyClass) {
                    Player.takeClass(numCyclesOffline);
                } else if (Player.workType == CONSTANTS.WorkTypeCrime) {
                    Player.commitCrime(numCyclesOffline);
                } else if (Player.workType == CONSTANTS.WorkTypeCompanyPartTime) {
                    Player.workPartTime(numCyclesOffline);
                } else {
                    Player.work(numCyclesOffline);
                }
            }
            
            //Hacknet Nodes offline progress
            processAllHacknetNodeEarnings(numCyclesOffline);
            
            //Passive faction rep gain offline
            processPassiveFactionRepGain(numCyclesOffline);
        } else {
            //No save found, start new game
            console.log("Initializing new game");
            SpecialServerIps = new SpecialServerIpsMap();
            Engine.setDisplayElements();        //Sets variables for important DOM elements
            Engine.start();                     //Run main game loop and Scripts loop
            Player.init();
            initForeignServers();
            initCompanies();
            initFactions();
            CompanyPositions.init();
            initAugmentations();
            
            //Start interactive tutorial
            iTutorialStart();
        }
    },
    
    setDisplayElements: function() {
        //Content elements        
        Engine.Display.terminalContent = document.getElementById("terminal-container");
        Engine.currentPage = Engine.Page.Terminal;
        
        Engine.Display.characterContent = document.getElementById("character-container");
        Engine.Display.characterContent.style.visibility = "hidden";
        
        Engine.Display.scriptEditorContent = document.getElementById("script-editor-container");
        Engine.Display.scriptEditorContent.style.visibility = "hidden";
        
        Engine.Display.activeScriptsContent = document.getElementById("active-scripts-container");
        Engine.Display.activeScriptsContent.style.visibility = "hidden";
        
        Engine.Display.hacknetNodesContent = document.getElementById("hacknet-nodes-container");
        Engine.Display.hacknetNodesContent.style.visibility = "hidden";
        
        Engine.Display.worldContent = document.getElementById("world-container");
        Engine.Display.worldContent.style.visibility = "hidden";
        
        Engine.Display.createProgramContent = document.getElementById("create-program-container");
        Engine.Display.createProgramContent.style.visibility = "hidden";
        
        Engine.Display.factionsContent = document.getElementById("factions-container");
        Engine.Display.factionsContent.style.visibility = "hidden";
        
        
        Engine.Display.factionContent = document.getElementById("faction-container");
        Engine.Display.factionContent.style.visibility = "hidden";
        
        Engine.Display.factionAugmentationsContent = document.getElementById("faction-augmentations-container");
        Engine.Display.factionAugmentationsContent.style.visibility = "hidden";
        
        Engine.Display.augmentationsContent = document.getElementById("augmentations-container");
        Engine.Display.augmentationsContent.style.visibility = "hidden";
        
        Engine.Display.tutorialContent = document.getElementById("tutorial-container");
        Engine.Display.tutorialContent.style.visibility = "hidden";
        
        //Character info
        Engine.Display.characterInfo = document.getElementById("character-info");
        
        //Location lists
        Engine.aevumLocationsList = document.getElementById("aevum-locations-list");
        Engine.chongqingLocationsList = document.getElementById("chongqing-locations-list");
        Engine.sector12LocationsList = document.getElementById("sector12-locations-list");
        Engine.newTokyoLocationsList = document.getElementById("newtokyo-locations-list");
        Engine.ishimaLocationsList = document.getElementById("ishima-locations-list");
        Engine.volhavenLocationsList = document.getElementById("volhaven-locations-list");
        
        //Location page (page that shows up when you visit a specific location in World)
        Engine.Display.locationContent = document.getElementById("location-container");
        Engine.Display.locationContent.style.visibility = "hidden";
        
        //Work In Progress
        Engine.Display.workInProgressContent = document.getElementById("work-in-progress-container");
        Engine.Display.workInProgressContent.style.visibility = "hidden";
		
		//Init Location buttons
		initLocationButtons();
        
        //Script editor 
        Engine.Display.scriptEditorText = document.getElementById("script-editor-text");
        
        //Tutorial buttons
        Engine.Clickables.tutorialGettingStartedButton = document.getElementById("tutorial-getting-started-link");
        Engine.Clickables.tutorialGettingStartedButton.addEventListener("click", function() {
            Engine.displayTutorialPage(CONSTANTS.TutorialGettingStartedText);
        });
        
        Engine.Clickables.tutorialNetworkingButton = document.getElementById("tutorial-networking-link");
        Engine.Clickables.tutorialNetworkingButton.addEventListener("click", function() {
            Engine.displayTutorialPage(CONSTANTS.TutorialNetworkingText);
        });
        
        Engine.Clickables.tutorialHackingButton = document.getElementById("tutorial-hacking-link");
        Engine.Clickables.tutorialHackingButton.addEventListener("click", function() {
            Engine.displayTutorialPage(CONSTANTS.TutorialHackingText);
        });
        
        Engine.Clickables.tutorialScriptsButton = document.getElementById("tutorial-scripts-link");
        Engine.Clickables.tutorialScriptsButton.addEventListener("click", function() {
            Engine.displayTutorialPage(CONSTANTS.TutorialScriptsText);
        });
        
        Engine.Clickables.tutorialNetscriptButton = document.getElementById("tutorial-netscript-link");
        Engine.Clickables.tutorialNetscriptButton.addEventListener("click", function() {
            Engine.displayTutorialPage(CONSTANTS.TutorialNetscriptText);
        });
        
        Engine.Clickables.tutorialTravelingButton = document.getElementById("tutorial-traveling-link");
        Engine.Clickables.tutorialTravelingButton.addEventListener("click", function() {
            Engine.displayTutorialPage(CONSTANTS.TutorialTravelingText);
        });
        
        Engine.Clickables.tutorialJobsButton = document.getElementById("tutorial-jobs-link");
        Engine.Clickables.tutorialJobsButton.addEventListener("click", function() {
            Engine.displayTutorialPage(CONSTANTS.TutorialJobsText);
        });
        
        Engine.Clickables.tutorialFactionsButton = document.getElementById("tutorial-factions-link");
        Engine.Clickables.tutorialFactionsButton.addEventListener("click", function() {
            Engine.displayTutorialPage(CONSTANTS.TutorialFactionsText);
        });
        
        Engine.Clickables.tutorialAugmentationsButton = document.getElementById("tutorial-augmentations-link");
        Engine.Clickables.tutorialAugmentationsButton.addEventListener("click", function() {
            Engine.displayTutorialPage(CONSTANTS.TutorialAugmentationsText);
        });
        
        Engine.Clickables.tutorialBackButton = document.getElementById("tutorial-back-button");
        Engine.Clickables.tutorialBackButton.addEventListener("click", function() {
            Engine.displayTutorialContent();
        });
        
        //If DarkWeb already purchased, disable the button
        if (SpecialServerIps.hasOwnProperty("Darkweb Server")) {
            document.getElementById("location-purchase-tor").setAttribute("class", "a-link-button-inactive");
        }
    },
    
    /* Initialization */
    init: function() {
        //Main menu buttons and content
        Engine.Clickables.terminalMainMenuButton = clearEventListeners("terminal-menu-link");
        Engine.Clickables.terminalMainMenuButton.addEventListener("click", function() {
            Engine.loadTerminalContent();
            return false;
        });
        
        Engine.Clickables.characterMainMenuButton = clearEventListeners("character-menu-link");
        Engine.Clickables.characterMainMenuButton.addEventListener("click", function() {
            Engine.loadCharacterContent();
            return false;
        });
        
        Engine.Clickables.scriptEditorMainMenuButton = clearEventListeners("create-script-menu-link");
        Engine.Clickables.scriptEditorMainMenuButton.addEventListener("click", function() {
            Engine.loadScriptEditorContent();
            return false;
        });
        
        Engine.Clickables.activeScriptsMainMenuButton = clearEventListeners("active-scripts-menu-link");
        Engine.Clickables.activeScriptsMainMenuButton.addEventListener("click", function() {
            Engine.loadActiveScriptsContent();
            return false;
        });
        
        Engine.Clickables.hacknetNodesMainMenuButton = clearEventListeners("hacknet-nodes-menu-link");
        Engine.Clickables.hacknetNodesMainMenuButton.addEventListener("click", function() {
            Engine.loadHacknetNodesContent();
            return false;
        });
        
        Engine.Clickables.worldMainMenuButton = clearEventListeners("world-menu-link");
        Engine.Clickables.worldMainMenuButton.addEventListener("click", function() {
            Engine.loadWorldContent();
            return false;
        });
        
        Engine.Clickables.createProgramMainMenuButton = clearEventListeners("create-program-menu-link");
        Engine.Clickables.createProgramMainMenuButton.addEventListener("click", function() {
            Engine.loadCreateProgramContent();
            return false;
        });
        
        Engine.Clickables.factionsMainMenuButton = clearEventListeners("factions-menu-link");
        Engine.Clickables.factionsMainMenuButton.addEventListener("click", function() {
            Engine.loadFactionsContent();
            return false;
        });
        
        Engine.Clickables.augmentationsMainMenuButton = clearEventListeners("augmentations-menu-link");
        Engine.Clickables.augmentationsMainMenuButton.addEventListener("click", function() {
            Engine.loadAugmentationsContent();
            return false;
        });
        
        Engine.Clickables.tutorialMainMenuButton = clearEventListeners("tutorial-menu-link");
        Engine.Clickables.tutorialMainMenuButton.addEventListener("click", function() {
            Engine.loadTutorialContent();
            return false;
        });
        
        //Active scripts list
        Engine.ActiveScriptsList = document.getElementById("active-scripts-list");
        
        //Save and Delete buttons
        Engine.Clickables.saveMainMenuButton = document.getElementById("save-game-link");
        Engine.Clickables.saveMainMenuButton.addEventListener("click", function() {
            saveObject.saveGame();
            return false;           
        });
        
        Engine.Clickables.deleteMainMenuButton = document.getElementById("delete-game-link");
        Engine.Clickables.deleteMainMenuButton.addEventListener("click", function() {
            saveObject.deleteGame();
            return false;
        });
        
        
        //Script Editor Netscript documentation button
        var netscriptDocButton = document.getElementById("script-editor-netscript-doc-button");
        netscriptDocButton.addEventListener("click", function() {
            Engine.loadTutorialContent();
            Engine.displayTutorialContent();
            Engine.displayTutorialPage(CONSTANTS.TutorialNetscriptText);
            return false;
        });
        
        //Create Program buttons
        var portHackALink   = document.getElementById("create-program-nuke");
        var bruteSshALink   = document.getElementById("create-program-brutessh");
        var ftpCrackALink   = document.getElementById("create-program-ftpcrack");
        var relaySmtpALink  = document.getElementById("create-program-relaysmtp");
        var httpWormALink   = document.getElementById("create-program-httpworm");
        var sqlInjectALink  = document.getElementById("create-program-sqlinject");
        portHackALink.addEventListener("click", function() {
            createProgram(Programs.PortHackProgram, CONSTANTS.MillisecondsPerQuarterHour);
        });
        bruteSshALink.addEventListener("click", function() {
            Player.startCreateProgramWork(Programs.BruteSSHProgram, CONSTANTS.MillisecondsPerQuarterHour);
        });
        ftpCrackALink.addEventListener("click", function() {
            Player.startCreateProgramWork(Programs.FTPCrackProgram, CONSTANTS.MillisecondsPerHalfHour);
        });
        relaySmtpALink.addEventListener("click", function() {
            Player.startCreateProgramWork(Programs.RelaySMTPProgram. CONSTANTS.MillisecondsPer2Hours);
        });
        httpWormALink.addEventListener("click", function() {
            Player.startCreateProgramWork(Programs.HTTPWormProgram, CONSTANTS.MillisecondsPer4Hours);
        });
        sqlInjectALink.addEventListener("click", function() {
            Player.startCreateProgramWork(Programs.SQLInjectProgram, CONSTANTS.MillisecondsPer8Hours);
        });
                
        //Message at the top of terminal
        postNetburnerText();
        
        //Player was working cancel button
        if (Player.isWorking) {
            var cancelButton = document.getElementById("work-in-progress-cancel-button");
            cancelButton.addEventListener("click", function() {
                if (Player.workType == CONSTANTS.WorkTypeFaction) {
                    var fac = Factions[Player.currentWorkFactionName];
                    Player.finishFactionWork(true, fac);
                } else if (Player.WorkType == CONSTANTS.WorkTypeCreateProgram) {
                    Player.finishCreateProgramWork(true, Player.createProgramName);
                } else if (Player.workType == CONSTANTS.WorkTypeStudyClass) {
                    Player.finishClass();
                } else if (Player.workType == CONSTANTS.WorkTypeCrime) {
                    Player.finishCrime(true);
                } else if (Player.workType == CONSTANTS.WorkTypeCompanyPartTime) {
                    Player.finishWorkPartTime();
                } else {
                    Player.finishWork(true);
                }
            });
            Engine.loadWorkInProgressContent();
        }
    },
    
    start: function() {
        //Run main loop
        Engine.idleTimer();
        
        //Scripts
        runScriptsLoop();
    }
};

window.onload = function() {
    Engine.load();
};