CCScheduler.js

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/**
 * @module cc
 */
const js = require('./platform/js');
const IdGenerater = require('./platform/id-generater');
const MAX_POOL_SIZE = 20;

var idGenerater = new IdGenerater('Scheduler');

//data structures
/*
 * A list double-linked list used for "updates with priority"
 * @class ListEntry
 * @param {Object} target not retained (retained by hashUpdateEntry)
 * @param {Number} priority
 * @param {Boolean} paused
 * @param {Boolean} markedForDeletion selector will no longer be called and entry will be removed at end of the next tick
 */
var ListEntry = function (target, priority, paused, markedForDeletion) {
    this.target = target;
    this.priority = priority;
    this.paused = paused;
    this.markedForDeletion = markedForDeletion;
};

var _listEntries = [];
ListEntry.get = function (target, priority, paused, markedForDeletion) {
    var result = _listEntries.pop();
    if (result) {
        result.target = target;
        result.priority = priority;
        result.paused = paused;
        result.markedForDeletion = markedForDeletion;
    }
    else {
        result = new ListEntry(target, priority, paused, markedForDeletion);
    }
    return result;
};
ListEntry.put = function (entry) {
    if (_listEntries.length < MAX_POOL_SIZE) {
        entry.target = null;
        _listEntries.push(entry);
    }
};

/*
 * A update entry list
 * @class HashUpdateEntry
 * @param {Array} list Which list does it belong to ?
 * @param {ListEntry} entry entry in the list
 * @param {Object} target hash key (retained)
 * @param {function} callback
 */
var HashUpdateEntry = function (list, entry, target, callback) {
    this.list = list;
    this.entry = entry;
    this.target = target;
    this.callback = callback;
};
var _hashUpdateEntries = [];
HashUpdateEntry.get = function (list, entry, target, callback) {
    var result = _hashUpdateEntries.pop();
    if (result) {
        result.list = list;
        result.entry = entry;
        result.target = target;
        result.callback = callback;
    }
    else {
        result = new HashUpdateEntry(list, entry, target, callback);
    }
    return result;
};
HashUpdateEntry.put = function (entry) {
    if (_hashUpdateEntries.length < MAX_POOL_SIZE) {
        entry.list = entry.entry = entry.target = entry.callback = null;
        _hashUpdateEntries.push(entry);
    }
};

//
/*
 * Hash Element used for "selectors with interval"
 * @class HashTimerEntry
 * @param {Array} timers
 * @param {Object} target  hash key (retained)
 * @param {Number} timerIndex
 * @param {Timer} currentTimer
 * @param {Boolean} currentTimerSalvaged
 * @param {Boolean} paused
 */
var HashTimerEntry = function (timers, target, timerIndex, currentTimer, currentTimerSalvaged, paused) {
    var _t = this;
    _t.timers = timers;
    _t.target = target;
    _t.timerIndex = timerIndex;
    _t.currentTimer = currentTimer;
    _t.currentTimerSalvaged = currentTimerSalvaged;
    _t.paused = paused;
};
var _hashTimerEntries = [];
HashTimerEntry.get = function (timers, target, timerIndex, currentTimer, currentTimerSalvaged, paused) {
    var result = _hashTimerEntries.pop();
    if (result) {
        result.timers = timers;
        result.target = target;
        result.timerIndex = timerIndex;
        result.currentTimer = currentTimer;
        result.currentTimerSalvaged = currentTimerSalvaged;
        result.paused = paused;
    }
    else {
        result = new HashTimerEntry(timers, target, timerIndex, currentTimer, currentTimerSalvaged, paused);
    }
    return result;
};
HashTimerEntry.put = function (entry) {
    if (_hashTimerEntries.length < MAX_POOL_SIZE) {
        entry.timers = entry.target = entry.currentTimer = null;
        _hashTimerEntries.push(entry);
    }
};

/*
 * Light weight timer
 * @extends cc.Class
 */
function CallbackTimer () {
    this._lock = false;
    this._scheduler = null;
    this._elapsed = -1;
    this._runForever = false;
    this._useDelay = false;
    this._timesExecuted = 0;
    this._repeat = 0;
    this._delay = 0;
    this._interval = 0;

    this._target = null;
    this._callback = null;
}

var proto = CallbackTimer.prototype;

proto.initWithCallback = function (scheduler, callback, target, seconds, repeat, delay) {
    this._lock = false;
    this._scheduler = scheduler;
    this._target = target;
    this._callback = callback;

    this._elapsed = -1;
    this._interval = seconds;
    this._delay = delay;
    this._useDelay = (this._delay > 0);
    this._repeat = repeat;
    this._runForever = (this._repeat === cc.macro.REPEAT_FOREVER);
    return true;
};
/**
 * @return {Number} returns interval of timer
 */
proto.getInterval = function(){return this._interval;};
/**
 * @param {Number} interval set interval in seconds
 */
proto.setInterval = function(interval){this._interval = interval;};

/**
 * triggers the timer
 * @param {Number} dt delta time
 */
proto.update = function (dt) {
    if (this._elapsed === -1) {
        this._elapsed = 0;
        this._timesExecuted = 0;
    } else {
        this._elapsed += dt;
        if (this._runForever && !this._useDelay) {//standard timer usage
            if (this._elapsed >= this._interval) {
                this.trigger();
                this._elapsed = 0;
            }
        } else {//advanced usage
            if (this._useDelay) {
                if (this._elapsed >= this._delay) {
                    this.trigger();

                    this._elapsed -= this._delay;
                    this._timesExecuted += 1;
                    this._useDelay = false;
                }
            } else {
                if (this._elapsed >= this._interval) {
                    this.trigger();

                    this._elapsed = 0;
                    this._timesExecuted += 1;
                }
            }

            if (this._callback && !this._runForever && this._timesExecuted > this._repeat)
                this.cancel();
        }
    }
};

proto.getCallback = function(){
    return this._callback;
};

proto.trigger = function () {
    if (this._target && this._callback) {
        this._lock = true;
        this._callback.call(this._target, this._elapsed);
        this._lock = false;
    }
};

proto.cancel = function () {
    //override
    this._scheduler.unschedule(this._callback, this._target);
};

var _timers = [];
CallbackTimer.get = function () {
    return _timers.pop() || new CallbackTimer();
};
CallbackTimer.put = function (timer) {
    if (_timers.length < MAX_POOL_SIZE && !timer._lock) {
        timer._scheduler = timer._target = timer._callback = null;
        _timers.push(timer);
    }
};

/**
 * !#en
 * Scheduler is responsible of triggering the scheduled callbacks.<br/>
 * You should not use NSTimer. Instead use this class.<br/>
 * <br/>
 * There are 2 different types of callbacks (selectors):<br/>
 *     - update callback: the 'update' callback will be called every frame. You can customize the priority.<br/>
 *     - custom callback: A custom callback will be called every frame, or with a custom interval of time<br/>
 * <br/>
 * The 'custom selectors' should be avoided when possible. It is faster,
 * and consumes less memory to use the 'update callback'. *
 * !#zh
 * Scheduler 是负责触发回调函数的类。<br/>
 * 通常情况下，建议使用 cc.director.getScheduler() 来获取系统定时器。<br/>
 * 有两种不同类型的定时器：<br/>
 *     - update 定时器：每一帧都会触发。您可以自定义优先级。<br/>
 *     - 自定义定时器：自定义定时器可以每一帧或者自定义的时间间隔触发。<br/>
 * 如果希望每帧都触发，应该使用 update 定时器，使用 update 定时器更快，而且消耗更少的内存。
 *
 * @class Scheduler
 */
cc.Scheduler = function () {
    this._timeScale = 1.0;
    this._updatesNegList = [];  // list of priority < 0
    this._updates0List = [];    // list of priority == 0
    this._updatesPosList = [];  // list of priority > 0
    this._hashForUpdates = js.createMap(true);  // hash used to fetch quickly the list entries for pause, delete, etc
    this._hashForTimers = js.createMap(true);   // Used for "selectors with interval"
    this._currentTarget = null;
    this._currentTargetSalvaged = false;
    this._updateHashLocked = false; // If true unschedule will not remove anything from a hash. Elements will only be marked for deletion.

    this._arrayForTimers = [];  // Speed up indexing
    //this._arrayForUpdates = [];   // Speed up indexing
};

cc.Scheduler.prototype = {
    constructor: cc.Scheduler,
    //-----------------------private method----------------------

    _removeHashElement: function (element) {
        delete this._hashForTimers[element.target._id];
        var arr = this._arrayForTimers;
        for (var i = 0, l = arr.length; i < l; i++) {
            if (arr[i] === element) {
                arr.splice(i, 1);
                break;
            }
        }
        HashTimerEntry.put(element);
    },

    _removeUpdateFromHash: function (entry) {
        var targetId = entry.target._id;
        var self = this, element = self._hashForUpdates[targetId];
        if (element) {
            // Remove list entry from list
            var list = element.list, listEntry = element.entry;
            for (var i = 0, l = list.length; i < l; i++) {
                if (list[i] === listEntry) {
                    list.splice(i, 1);
                    break;
                }
            }

            delete self._hashForUpdates[targetId];
            ListEntry.put(listEntry);
            HashUpdateEntry.put(element);
        }
    },

    _priorityIn: function (ppList, listElement, priority) {
        for (var i = 0; i < ppList.length; i++){
            if (priority < ppList[i].priority) {
                ppList.splice(i, 0, listElement);
                return;
            }
        }
        ppList.push(listElement);
    },

    _appendIn: function (ppList, listElement) {
        ppList.push(listElement);
    },

    //-----------------------public method-------------------------
    /**
     * !en This method should be called for any target which needs to schedule tasks, and this method should be called before any scheduler API usage.
     * This method will add a `_id` property if it doesn't exist.
     * !zh 任何需要用 Scheduler 管理任务的对象主体都应该调用这个方法，并且应该在调用任何 Scheduler API 之前调用这个方法。
     * 这个方法会给对象添加一个 `_id` 属性，如果这个属性不存在的话。
     * @method enableForTarget
     * @param {Object} target
     */
    enableForTarget: function (target) {
        if (!target._id) {
            if (target.__instanceId) {
                cc.warnID(1513);
            }
            else {
                target._id = idGenerater.getNewId();
            }
        }
    },

    /**
     * !#en
     * Modifies the time of all scheduled callbacks.<br/>
     * You can use this property to create a 'slow motion' or 'fast forward' effect.<br/>
     * Default is 1.0. To create a 'slow motion' effect, use values below 1.0.<br/>
     * To create a 'fast forward' effect, use values higher than 1.0.<br/>
     * Note：It will affect EVERY scheduled selector / action.
     * !#zh
     * 设置时间间隔的缩放比例。<br/>
     * 您可以使用这个方法来创建一个 “slow motion（慢动作）” 或 “fast forward（快进）” 的效果。<br/>
     * 默认是 1.0。要创建一个 “slow motion（慢动作）” 效果,使用值低于 1.0。<br/>
     * 要使用 “fast forward（快进）” 效果，使用值大于 1.0。<br/>
     * 注意：它影响该 Scheduler 下管理的所有定时器。
     * @method setTimeScale
     * @param {Number} timeScale
     */
    setTimeScale: function (timeScale) {
        this._timeScale = timeScale;
    },

    /**
     * !#en Returns time scale of scheduler.
     * !#zh 获取时间间隔的缩放比例。
     * @method getTimeScale
     * @return {Number}
     */
    getTimeScale: function () {
        return this._timeScale;
    },

    /**
     * !#en 'update' the scheduler. (You should NEVER call this method, unless you know what you are doing.)
     * !#zh update 调度函数。(不应该直接调用这个方法，除非完全了解这么做的结果)
     * @method update
     * @param {Number} dt delta time
     */
    update: function (dt) {
        this._updateHashLocked = true;
        if(this._timeScale !== 1)
            dt *= this._timeScale;

        var i, list, len, entry;

        for(i=0,list=this._updatesNegList, len = list.length; i<len; i++){
            entry = list[i];
            if (!entry.paused && !entry.markedForDeletion)
                entry.target.update(dt);
        }

        for(i=0, list=this._updates0List, len=list.length; i<len; i++){
            entry = list[i];
            if (!entry.paused && !entry.markedForDeletion)
                entry.target.update(dt);
        }

        for(i=0, list=this._updatesPosList, len=list.length; i<len; i++){
            entry = list[i];
            if (!entry.paused && !entry.markedForDeletion)
                entry.target.update(dt);
        }

        // Iterate over all the custom selectors
        var elt, arr = this._arrayForTimers;
        for(i=0; i<arr.length; i++){
            elt = arr[i];
            this._currentTarget = elt;
            this._currentTargetSalvaged = false;

            if (!elt.paused){
                // The 'timers' array may change while inside this loop
                for (elt.timerIndex = 0; elt.timerIndex < elt.timers.length; ++(elt.timerIndex)){
                    elt.currentTimer = elt.timers[elt.timerIndex];
                    elt.currentTimerSalvaged = false;

                    elt.currentTimer.update(dt);
                    elt.currentTimer = null;
                }
            }

            // only delete currentTarget if no actions were scheduled during the cycle (issue #481)
            if (this._currentTargetSalvaged && this._currentTarget.timers.length === 0) {
                this._removeHashElement(this._currentTarget);
                --i;
            }
        }

        // delete all updates that are marked for deletion
        // updates with priority < 0
        for(i=0,list=this._updatesNegList; i<list.length; ){
            entry = list[i];
            if(entry.markedForDeletion)
                this._removeUpdateFromHash(entry);
            else
                i++;
        }

        for(i=0, list=this._updates0List; i<list.length; ){
            entry = list[i];
            if (entry.markedForDeletion)
                this._removeUpdateFromHash(entry);
            else
                i++;
        }

        for(i=0, list=this._updatesPosList; i<list.length; ){
            entry = list[i];
            if (entry.markedForDeletion)
                this._removeUpdateFromHash(entry);
            else
                i++;
        }

        this._updateHashLocked = false;
        this._currentTarget = null;
    },

    /**
     * !#en
     * <p>
     *   The scheduled method will be called every 'interval' seconds.<br/>
     *   If paused is YES, then it won't be called until it is resumed.<br/>
     *   If 'interval' is 0, it will be called every frame, but if so, it recommended to use 'scheduleUpdateForTarget:' instead.<br/>
     *   If the callback function is already scheduled, then only the interval parameter will be updated without re-scheduling it again.<br/>
     *   repeat let the action be repeated repeat + 1 times, use cc.macro.REPEAT_FOREVER to let the action run continuously<br/>
     *   delay is the amount of time the action will wait before it'll start<br/>
     * </p>
     * !#zh
     * 指定回调函数，调用对象等信息来添加一个新的定时器。<br/>
     * 如果 paused 值为 true，那么直到 resume 被调用才开始计时。<br/>
     * 当时间间隔达到指定值时，设置的回调函数将会被调用。<br/>
     * 如果 interval 值为 0，那么回调函数每一帧都会被调用，但如果是这样，
     * 建议使用 scheduleUpdateForTarget 代替。<br/>
     * 如果回调函数已经被定时器使用，那么只会更新之前定时器的时间间隔参数，不会设置新的定时器。<br/>
     * repeat 值可以让定时器触发 repeat + 1 次，使用 cc.macro.REPEAT_FOREVER
     * 可以让定时器一直循环触发。<br/>
     * delay 值指定延迟时间，定时器会在延迟指定的时间之后开始计时。
     * @method schedule
     * @param {Function} callback
     * @param {Object} target
     * @param {Number} interval
     * @param {Number} [repeat=cc.macro.REPEAT_FOREVER]
     * @param {Number} [delay=0]
     * @param {Boolean} paused
     * @example {@link cocos2d/core/CCScheduler/schedule.js}
     * @typescript
     * schedule(callback: Function, target: any, interval: number, repeat: number, delay: number, paused?: boolean): void
     * schedule(callback: Function, target: any, interval: number, paused?: boolean): void
     */
    schedule: function (callback, target, interval, repeat, delay, paused) {
        'use strict';
        if (typeof callback !== 'function') {
            var tmp = callback;
            callback = target;
            target = tmp;
        }
        //selector, target, interval, repeat, delay, paused
        //selector, target, interval, paused
        if (arguments.length === 4 || arguments.length === 5) {
            paused = !!repeat;
            repeat = cc.macro.REPEAT_FOREVER;
            delay = 0;
        }

        cc.assertID(target, 1502);

        var targetId = target._id;
        if (!targetId) {
            if (target.__instanceId) {
                cc.warnID(1513);
                targetId = target._id = target.__instanceId;
            }
            else {
                cc.errorID(1510);
            }
        }
        var element = this._hashForTimers[targetId];
        if (!element) {
            // Is this the 1st element ? Then set the pause level to all the callback_fns of this target
            element = HashTimerEntry.get(null, target, 0, null, null, paused);
            this._arrayForTimers.push(element);
            this._hashForTimers[targetId] = element;
        } else if (element.paused !== paused) {
            cc.warnID(1511);
        }

        var timer, i;
        if (element.timers == null) {
            element.timers = [];
        }
        else {
            for (i = 0; i < element.timers.length; ++i) {
                timer = element.timers[i];
                if (timer && callback === timer._callback) {
                    cc.logID(1507, timer.getInterval(), interval);
                    timer._interval = interval;
                    return;
                }
            }
        }

        timer = CallbackTimer.get();
        timer.initWithCallback(this, callback, target, interval, repeat, delay);
        element.timers.push(timer);

        if (this._currentTarget === element && this._currentTargetSalvaged) {
            this._currentTargetSalvaged = false;
        }
    },

    /**
     * !#en
     * Schedules the update callback for a given target,
     * During every frame after schedule started, the "update" function of target will be invoked.
     * !#zh
     * 使用指定的优先级为指定的对象设置 update 定时器。
     * update 定时器每一帧都会被触发，触发时自动调用指定对象的 "update" 函数。
     * 优先级的值越低，定时器被触发的越早。
     * @method scheduleUpdate
     * @param {Object} target
     * @param {Number} priority
     * @param {Boolean} paused
     */
    scheduleUpdate: function(target, priority, paused) {
        var targetId = target._id;
        if (!targetId) {
            if (target.__instanceId) {
                cc.warnID(1513);
                targetId = target._id = target.__instanceId;
            }
            else {
                cc.errorID(1510);
            }
        }
        var hashElement = this._hashForUpdates[targetId];
        if (hashElement && hashElement.entry){
            // check if priority has changed
            if (hashElement.entry.priority !== priority){
                if (this._updateHashLocked){
                    cc.logID(1506);
                    hashElement.entry.markedForDeletion = false;
                    hashElement.entry.paused = paused;
                    return;
                }else{
                    // will be added again outside if (hashElement).
                    this.unscheduleUpdate(target);
                }
            }else{
                hashElement.entry.markedForDeletion = false;
                hashElement.entry.paused = paused;
                return;
            }
        }

        var listElement = ListEntry.get(target, priority, paused, false);
        var ppList;

        // most of the updates are going to be 0, that's way there
        // is an special list for updates with priority 0
        if (priority === 0) {
            ppList = this._updates0List;
            this._appendIn(ppList, listElement);
        }
        else {
            ppList = priority < 0 ? this._updatesNegList : this._updatesPosList;
            this._priorityIn(ppList, listElement, priority);
        }

        //update hash entry for quick access
        this._hashForUpdates[targetId] = HashUpdateEntry.get(ppList, listElement, target, null);
    },

    /**
     * !#en
     * Unschedules a callback for a callback and a given target.
     * If you want to unschedule the "update", use `unscheduleUpdate()`
     * !#zh
     * 取消指定对象定时器。
     * 如果需要取消 update 定时器，请使用 unscheduleUpdate()。
     * @method unschedule
     * @param {Function} callback The callback to be unscheduled
     * @param {Object} target The target bound to the callback.
     */
    unschedule: function (callback, target) {
        //callback, target

        // explicity handle nil arguments when removing an object
        if (!target || !callback)
            return;
        var targetId = target._id;
        if (!targetId) {
            if (target.__instanceId) {
                cc.warnID(1513);
                targetId = target._id = target.__instanceId;
            }
            else {
                cc.errorID(1510);
            }
        }

        var self = this, element = self._hashForTimers[targetId];
        if (element) {
            var timers = element.timers;
            for(var i = 0, li = timers.length; i < li; i++){
                var timer = timers[i];
                if (callback === timer._callback) {
                    if ((timer === element.currentTimer) && (!element.currentTimerSalvaged)) {
                        element.currentTimerSalvaged = true;
                    }
                    timers.splice(i, 1);
                    CallbackTimer.put(timer);
                    //update timerIndex in case we are in tick;, looping over the actions
                    if (element.timerIndex >= i) {
                        element.timerIndex--;
                    }

                    if (timers.length === 0) {
                        if (self._currentTarget === element) {
                            self._currentTargetSalvaged = true;
                        } else {
                            self._removeHashElement(element);
                        }
                    }
                    return;
                }
            }
        }
    },

    /** 
     * !#en Unschedules the update callback for a given target.
     * !#zh 取消指定对象的 update 定时器。
     * @method unscheduleUpdate
     * @param {Object} target The target to be unscheduled.
     */
    unscheduleUpdate: function (target) {
        if (!target)
            return;
        var targetId = target._id;
        if (!targetId) {
            if (target.__instanceId) {
                cc.warnID(1513);
                targetId = target._id = target.__instanceId;
            }
            else {
                cc.errorID(1510);
            }
        }

        var element = this._hashForUpdates[targetId];
        if (element) {
            if (this._updateHashLocked) {
                element.entry.markedForDeletion = true;
            } else {
                this._removeUpdateFromHash(element.entry);
            }
        }
    },

    /** 
     * !#en
     * Unschedules all scheduled callbacks for a given target.
     * This also includes the "update" callback.
     * !#zh 取消指定对象的所有定时器，包括 update 定时器。
     * @method unscheduleAllForTarget
     * @param {Object} target The target to be unscheduled.
     */
    unscheduleAllForTarget: function (target) {
        // explicit nullptr handling
        if (!target){
            return;
        }
        var targetId = target._id;
        if (!targetId) {
            if (target.__instanceId) {
                cc.warnID(1513);
                targetId = target._id = target.__instanceId;
            }
            else {
                cc.errorID(1510);
            }
        }

        // Custom Selectors
        var element = this._hashForTimers[targetId];
        if (element) {
            var timers = element.timers;
            if (timers.indexOf(element.currentTimer) > -1 && 
                (!element.currentTimerSalvaged)) {
                element.currentTimerSalvaged = true;
            }
            for (var i = 0, l = timers.length; i < l; i++) {
                CallbackTimer.put(timers[i]);
            }
            timers.length = 0;

            if (this._currentTarget === element){
                this._currentTargetSalvaged = true;
            }else{
                this._removeHashElement(element);
            }
        }

        // update selector
        this.unscheduleUpdate(target);
    },

    /**
     * !#en
     * Unschedules all scheduled callbacks from all targets including the system callbacks.<br/>
     * You should NEVER call this method, unless you know what you are doing.
     * !#zh
     * 取消所有对象的所有定时器，包括系统定时器。<br/>
     * 不用调用此函数，除非你确定你在做什么。
     * @method unscheduleAll
     */
    unscheduleAll: function(){
        this.unscheduleAllWithMinPriority(cc.Scheduler.PRIORITY_SYSTEM);
    },

    /**
     * !#en
     * Unschedules all callbacks from all targets with a minimum priority.<br/>
     * You should only call this with `PRIORITY_NON_SYSTEM_MIN` or higher.
     * !#zh
     * 取消所有优先级的值大于指定优先级的定时器。<br/>
     * 你应该只取消优先级的值大于 PRIORITY_NON_SYSTEM_MIN 的定时器。
     * @method unscheduleAllWithMinPriority
     * @param {Number} minPriority The minimum priority of selector to be unscheduled. Which means, all selectors which
     *        priority is higher than minPriority will be unscheduled.
     */
    unscheduleAllWithMinPriority: function(minPriority){
        // Custom Selectors
        var i, element, arr = this._arrayForTimers;
        for(i=arr.length-1; i>=0; i--){
            element = arr[i];
            this.unscheduleAllForTarget(element.target);
        }

        // Updates selectors
        var entry;
        var temp_length = 0;
        if(minPriority < 0){
            for(i=0; i<this._updatesNegList.length; ){
                temp_length = this._updatesNegList.length;
                entry = this._updatesNegList[i];
                if(entry && entry.priority >= minPriority)
                    this.unscheduleUpdate(entry.target);
                if (temp_length == this._updatesNegList.length)
                    i++;
            }
        }

        if(minPriority <= 0){
            for(i=0; i<this._updates0List.length; ){
                temp_length = this._updates0List.length;
                entry = this._updates0List[i];
                if (entry)
                    this.unscheduleUpdate(entry.target);
                if (temp_length == this._updates0List.length)
                    i++;
            }
        }

        for(i=0; i<this._updatesPosList.length; ){
            temp_length = this._updatesPosList.length;
            entry = this._updatesPosList[i];
            if(entry && entry.priority >= minPriority)
                this.unscheduleUpdate(entry.target);
            if (temp_length == this._updatesPosList.length)
                i++;
        }
    },

    /** 
     * !#en Checks whether a callback for a given target is scheduled.
     * !#zh 检查指定的回调函数和回调对象组合是否存在定时器。
     * @method isScheduled
     * @param {Function} callback The callback to check.
     * @param {Object} target The target of the callback.
     * @return {Boolean} True if the specified callback is invoked, false if not.
     */
    isScheduled: function(callback, target){
        //key, target
        //selector, target
        cc.assertID(callback, 1508);
        cc.assertID(target, 1509);
        var targetId = target._id;
        if (!targetId) {
            if (target.__instanceId) {
                cc.warnID(1513);
                targetId = target._id = target.__instanceId;
            }
            else {
                cc.errorID(1510);
            }
        }
        
        var element = this._hashForTimers[targetId];

        if (!element) {
            return false;
        }

        if (element.timers == null){
            return false;
        }
        else {
            var timers = element.timers;
            for (var i = 0; i < timers.length; ++i) {
                var timer =  timers[i];

                if (callback === timer._callback){
                    return true;
                }
            }
            return false;
        }
    },

    /**
     * !#en
     * Pause all selectors from all targets.<br/>
     * You should NEVER call this method, unless you know what you are doing.
     * !#zh
     * 暂停所有对象的所有定时器。<br/>
     * 不要调用这个方法，除非你知道你正在做什么。
     * @method pauseAllTargets
     */
    pauseAllTargets: function () {
        return this.pauseAllTargetsWithMinPriority(cc.Scheduler.PRIORITY_SYSTEM);
    },

    /**
     * !#en
     * Pause all selectors from all targets with a minimum priority. <br/>
     * You should only call this with kCCPriorityNonSystemMin or higher.
     * !#zh
     * 暂停所有优先级的值大于指定优先级的定时器。<br/>
     * 你应该只暂停优先级的值大于 PRIORITY_NON_SYSTEM_MIN 的定时器。
     * @method pauseAllTargetsWithMinPriority
     * @param {Number} minPriority
     */
    pauseAllTargetsWithMinPriority: function (minPriority) {
        var idsWithSelectors = [];

        var self = this, element, locArrayForTimers = self._arrayForTimers;
        var i, li;
        // Custom Selectors
        for(i = 0, li = locArrayForTimers.length; i < li; i++){
            element = locArrayForTimers[i];
            if (element) {
                element.paused = true;
                idsWithSelectors.push(element.target);
            }
        }

        var entry;
        if(minPriority < 0){
            for(i=0; i<this._updatesNegList.length; i++){
                entry = this._updatesNegList[i];
                if (entry) {
                    if(entry.priority >= minPriority){
                        entry.paused = true;
                        idsWithSelectors.push(entry.target);
                    }
                }
            }
        }

        if(minPriority <= 0){
            for(i=0; i<this._updates0List.length; i++){
                entry = this._updates0List[i];
                if (entry) {
                    entry.paused = true;
                    idsWithSelectors.push(entry.target);
                }
            }
        }

        for(i=0; i<this._updatesPosList.length; i++){
            entry = this._updatesPosList[i];
            if (entry) {
                if(entry.priority >= minPriority){
                    entry.paused = true;
                    idsWithSelectors.push(entry.target);
                }
            }
        }

        return idsWithSelectors;
    },

    /**
     * !#en
     * Resume selectors on a set of targets.<br/>
     * This can be useful for undoing a call to pauseAllCallbacks.
     * !#zh
     * 恢复指定数组中所有对象的定时器。<br/>
     * 这个函数是 pauseAllCallbacks 的逆操作。
     * @method resumeTargets
     * @param {Array} targetsToResume
     */
    resumeTargets: function (targetsToResume) {
        if (!targetsToResume)
            return;

        for (var i = 0; i < targetsToResume.length; i++) {
            this.resumeTarget(targetsToResume[i]);
        }
    },

    /**
     * !#en
     * Pauses the target.<br/>
     * All scheduled selectors/update for a given target won't be 'ticked' until the target is resumed.<br/>
     * If the target is not present, nothing happens.
     * !#zh
     * 暂停指定对象的定时器。<br/>
     * 指定对象的所有定时器都会被暂停。<br/>
     * 如果指定的对象没有定时器，什么也不会发生。
     * @method pauseTarget
     * @param {Object} target
     */
    pauseTarget: function (target) {
        cc.assertID(target, 1503);
        var targetId = target._id;
        if (!targetId) {
            if (target.__instanceId) {
                cc.warnID(1513);
                targetId = target._id = target.__instanceId;
            }
            else {
                cc.errorID(1510);
            }
        }

        //customer selectors
        var self = this, 
            element = self._hashForTimers[targetId];
        if (element) {
            element.paused = true;
        }

        //update callback
        var elementUpdate = self._hashForUpdates[targetId];
        if (elementUpdate) {
            elementUpdate.entry.paused = true;
        }
    },

    /**
     * !#en
     * Resumes the target.<br/>
     * The 'target' will be unpaused, so all schedule selectors/update will be 'ticked' again.<br/>
     * If the target is not present, nothing happens.
     * !#zh
     * 恢复指定对象的所有定时器。<br/>
     * 指定对象的所有定时器将继续工作。<br/>
     * 如果指定的对象没有定时器，什么也不会发生。
     * @method resumeTarget
     * @param {Object} target
     */
    resumeTarget: function (target) {
        cc.assertID(target, 1504);
        var targetId = target._id;
        if (!targetId) {
            if (target.__instanceId) {
                cc.warnID(1513);
                targetId = target._id = target.__instanceId;
            }
            else {
                cc.errorID(1510);
            }
        }

        // custom selectors
        var self = this,
            element = self._hashForTimers[targetId];
        if (element) {
            element.paused = false;
        }

        //update callback
        var elementUpdate = self._hashForUpdates[targetId];
        if (elementUpdate) {
            elementUpdate.entry.paused = false;
        }
    },

    /**
     * !#en Returns whether or not the target is paused.
     * !#zh 返回指定对象的定时器是否暂停了。
     * @method isTargetPaused
     * @param {Object} target
     * @return {Boolean}
     */
    isTargetPaused: function (target) {
        cc.assertID(target, 1505);
        var targetId = target._id;
        if (!targetId) {
            if (target.__instanceId) {
                cc.warnID(1513);
                targetId = target._id = target.__instanceId;
            }
            else {
                cc.errorID(1510);
            }
        }

        // Custom selectors
        var element = this._hashForTimers[targetId];
        if (element) {
            return element.paused;
        }
        var elementUpdate = this._hashForUpdates[targetId];
        if (elementUpdate) {
            return elementUpdate.entry.paused;
        }
        return false;
    },
};

/**
 * !#en Priority level reserved for system services.
 * !#zh 系统服务的优先级。
 * @property PRIORITY_SYSTEM
 * @type {Number}
 * @static
 */
cc.Scheduler.PRIORITY_SYSTEM = 1 << 31;

/**
 * !#en Minimum priority level for user scheduling.
 * !#zh 用户调度最低优先级。
 * @property PRIORITY_NON_SYSTEM
 * @type {Number}
 * @static
 */
cc.Scheduler.PRIORITY_NON_SYSTEM = cc.Scheduler.PRIORITY_SYSTEM + 1;

module.exports = cc.Scheduler;