var Class = require('../utils/Class'); 
var PluginCache = require('../plugins/PluginCache'); 
var SceneEvents = require('../scene/events'); 
var TimerEvent = require('./TimerEvent'); 
var Clock = new Class({ 
initialize: function Clock(scene){ 
this.scene = scene; 
this.systems = scene.sys; 
this.now = 0; 
this.timeScale = 1; 
this.paused = false ; 
this._active = [] ; 
this._pendingInsertion = [] ; 
this._pendingRemoval = [] ; 
scene.sys.events.once(SceneEvents.BOOT, this.boot, this); 
scene.sys.events.on(SceneEvents.START, this.start, this); 
} 
,
boot: function (){ 
this.now = this.systems.game.loop.time; 
this.systems.events.once(SceneEvents.DESTROY, this.destroy, this); 
} 
,
start: function (){ 
var eventEmitter = this.systems.events; 
eventEmitter.on(SceneEvents.PRE_UPDATE, this.preUpdate, this); 
eventEmitter.on(SceneEvents.UPDATE, this.update, this); 
eventEmitter.once(SceneEvents.SHUTDOWN, this.shutdown, this); 
} 
,
addEvent: function (config){ 
var event = new TimerEvent(config); 
this._pendingInsertion.push(event); 
return event; 
} 
,
delayedCall: function (delay, callback, args, callbackScope){ 
return this.addEvent({ 
delay: delay,
callback: callback,
args: args,
callbackScope: callbackScope}
); 
} 
,
clearPendingEvents: function (){ 
this._pendingInsertion = [] ; 
return this; 
} 
,
removeAllEvents: function (){ 
this._pendingRemoval = this._pendingRemoval.concat(this._active); 
return this; 
} 
,
preUpdate: function (){ 
var toRemove = _AN_Read_length('length', this._pendingRemoval); 
var toInsert = _AN_Read_length('length', this._pendingInsertion); 
if (toRemove === 0 && toInsert === 0) { 
return ; 
} 
var i; 
var event; 
for (i = 0; i < toRemove; i++ ){ 
event = this._pendingRemoval[i]; 
var index = this._active.indexOf(event); 
if (index > -1) { 
this._active.splice(index, 1); 
} 
event.destroy(); 
} 
for (i = 0; i < toInsert; i++ ){ 
event = this._pendingInsertion[i]; 
this._active.push(event); 
} 
this._pendingRemoval.length = 0; 
this._pendingInsertion.length = 0; 
} 
,
update: function (time, delta){ 
this.now = time; 
if (this.paused) { 
return ; 
} 
delta *= this.timeScale; 
for (var i = 0; 
i < (_AN_Read_length('length', this._active)); i++ ){ 
var event = this._active[i]; 
if (event.paused) { 
continue ; 
} 
event.elapsed += delta * event.timeScale; 
if (event.elapsed >= event.delay) { 
var remainder = event.elapsed - event.delay; 
event.elapsed = event.delay; 
if (!event.hasDispatched && event.callback) { 
event.hasDispatched = true ; 
event.callback.apply(event.callbackScope, event.args); 
} 
if (event.repeatCount > 0) { 
event.repeatCount-- ; 
event.elapsed = remainder; 
event.hasDispatched = false ; 
} 
 else { 
this._pendingRemoval.push(event); 
} 
} 
} 
} 
,
shutdown: function (){ 
var i; 
for (i = 0; i < (_AN_Read_length('length', this._pendingInsertion)); i++ ){ 
this._pendingInsertion[i].destroy(); 
} 
for (i = 0; i < (_AN_Read_length('length', this._active)); i++ ){ 
this._active[i].destroy(); 
} 
for (i = 0; i < (_AN_Read_length('length', this._pendingRemoval)); i++ ){ 
this._pendingRemoval[i].destroy(); 
} 
this._active.length = 0; 
this._pendingRemoval.length = 0; 
this._pendingInsertion.length = 0; 
var eventEmitter = this.systems.events; 
eventEmitter.off(SceneEvents.PRE_UPDATE, this.preUpdate, this); 
eventEmitter.off(SceneEvents.UPDATE, this.update, this); 
eventEmitter.off(SceneEvents.SHUTDOWN, this.shutdown, this); 
} 
,
destroy: function (){ 
this.shutdown(); 
this.scene.sys.events.off(SceneEvents.START, this.start, this); 
this.scene = null ; 
this.systems = null ; 
} 
}
); 
PluginCache.register('Clock', Clock, 'time'); 
module.exports = Clock;