(function () {
/**
* Config is a utility used within an Object to allow the implementer to
* maintain a list of local configuration properties and listen for changes
* to those properties dynamically using CustomEvent. The initial values are
* also maintained so that the configuration can be reset at any given point
* to its initial state.
* @namespace YAHOO.util
* @class Config
* @constructor
* @param {Object} owner The owner Object to which this Config Object belongs
*/
YAHOO.util.Config = function (owner) {
if (owner) {
this.init(owner);
}
if (!owner) { YAHOO.log("No owner specified for Config object", "error", "Config"); }
};
var Lang = YAHOO.lang,
CustomEvent = YAHOO.util.CustomEvent,
Config = YAHOO.util.Config;
/**
* Constant representing the CustomEvent type for the config changed event.
* @property YAHOO.util.Config.CONFIG_CHANGED_EVENT
* @private
* @static
* @final
*/
Config.CONFIG_CHANGED_EVENT = "configChanged";
/**
* Constant representing the boolean type string
* @property YAHOO.util.Config.BOOLEAN_TYPE
* @private
* @static
* @final
*/
Config.BOOLEAN_TYPE = "boolean";
Config.prototype = {
/**
* Object reference to the owner of this Config Object
* @property owner
* @type Object
*/
owner: null,
/**
* Boolean flag that specifies whether a queue is currently
* being executed
* @property queueInProgress
* @type Boolean
*/
queueInProgress: false,
/**
* Maintains the local collection of configuration property objects and
* their specified values
* @property config
* @private
* @type Object
*/
config: null,
/**
* Maintains the local collection of configuration property objects as
* they were initially applied.
* This object is used when resetting a property.
* @property initialConfig
* @private
* @type Object
*/
initialConfig: null,
/**
* Maintains the local, normalized CustomEvent queue
* @property eventQueue
* @private
* @type Object
*/
eventQueue: null,
/**
* Custom Event, notifying subscribers when Config properties are set
* (setProperty is called without the silent flag
* @event configChangedEvent
*/
configChangedEvent: null,
/**
* Initializes the configuration Object and all of its local members.
* @method init
* @param {Object} owner The owner Object to which this Config
* Object belongs
*/
init: function (owner) {
this.owner = owner;
this.configChangedEvent =
this.createEvent(Config.CONFIG_CHANGED_EVENT);
this.configChangedEvent.signature = CustomEvent.LIST;
this.queueInProgress = false;
this.config = {};
this.initialConfig = {};
this.eventQueue = [];
},
/**
* Validates that the value passed in is a Boolean.
* @method checkBoolean
* @param {Object} val The value to validate
* @return {Boolean} true, if the value is valid
*/
checkBoolean: function (val) {
return (typeof val == Config.BOOLEAN_TYPE);
},
/**
* Validates that the value passed in is a number.
* @method checkNumber
* @param {Object} val The value to validate
* @return {Boolean} true, if the value is valid
*/
checkNumber: function (val) {
return (!isNaN(val));
},
/**
* Fires a configuration property event using the specified value.
* @method fireEvent
* @private
* @param {String} key The configuration property's name
* @param {value} Object The value of the correct type for the property
*/
fireEvent: function ( key, value ) {
YAHOO.log("Firing Config event: " + key + "=" + value, "info", "Config");
var property = this.config[key];
if (property && property.event) {
property.event.fire(value);
}
},
/**
* Adds a property to the Config Object's private config hash.
* @method addProperty
* @param {String} key The configuration property's name
* @param {Object} propertyObject The Object containing all of this
* property's arguments
*/
addProperty: function ( key, propertyObject ) {
key = key.toLowerCase();
YAHOO.log("Added property: " + key, "info", "Config");
this.config[key] = propertyObject;
propertyObject.event = this.createEvent(key, { scope: this.owner });
propertyObject.event.signature = CustomEvent.LIST;
propertyObject.key = key;
if (propertyObject.handler) {
propertyObject.event.subscribe(propertyObject.handler,
this.owner);
}
this.setProperty(key, propertyObject.value, true);
if (! propertyObject.suppressEvent) {
this.queueProperty(key, propertyObject.value);
}
},
/**
* Returns a key-value configuration map of the values currently set in
* the Config Object.
* @method getConfig
* @return {Object} The current config, represented in a key-value map
*/
getConfig: function () {
var cfg = {},
currCfg = this.config,
prop,
property;
for (prop in currCfg) {
if (Lang.hasOwnProperty(currCfg, prop)) {
property = currCfg[prop];
if (property && property.event) {
cfg[prop] = property.value;
}
}
}
return cfg;
},
/**
* Returns the value of specified property.
* @method getProperty
* @param {String} key The name of the property
* @return {Object} The value of the specified property
*/
getProperty: function (key) {
var property = this.config[key.toLowerCase()];
if (property && property.event) {
return property.value;
} else {
return undefined;
}
},
/**
* Resets the specified property's value to its initial value.
* @method resetProperty
* @param {String} key The name of the property
* @return {Boolean} True is the property was reset, false if not
*/
resetProperty: function (key) {
key = key.toLowerCase();
var property = this.config[key];
if (property && property.event) {
if (this.initialConfig[key] &&
!Lang.isUndefined(this.initialConfig[key])) {
this.setProperty(key, this.initialConfig[key]);
return true;
}
} else {
return false;
}
},
/**
* Sets the value of a property. If the silent property is passed as
* true, the property's event will not be fired.
* @method setProperty
* @param {String} key The name of the property
* @param {String} value The value to set the property to
* @param {Boolean} silent Whether the value should be set silently,
* without firing the property event.
* @return {Boolean} True, if the set was successful, false if it failed.
*/
setProperty: function (key, value, silent) {
var property;
key = key.toLowerCase();
YAHOO.log("setProperty: " + key + "=" + value, "info", "Config");
if (this.queueInProgress && ! silent) {
// Currently running through a queue...
this.queueProperty(key,value);
return true;
} else {
property = this.config[key];
if (property && property.event) {
if (property.validator && !property.validator(value)) {
return false;
} else {
property.value = value;
if (! silent) {
this.fireEvent(key, value);
this.configChangedEvent.fire([key, value]);
}
return true;
}
} else {
return false;
}
}
},
/**
* Sets the value of a property and queues its event to execute. If the
* event is already scheduled to execute, it is
* moved from its current position to the end of the queue.
* @method queueProperty
* @param {String} key The name of the property
* @param {String} value The value to set the property to
* @return {Boolean} true, if the set was successful, false if
* it failed.
*/
queueProperty: function (key, value) {
key = key.toLowerCase();
YAHOO.log("queueProperty: " + key + "=" + value, "info", "Config");
var property = this.config[key],
foundDuplicate = false,
iLen,
queueItem,
queueItemKey,
queueItemValue,
sLen,
supercedesCheck,
qLen,
queueItemCheck,
queueItemCheckKey,
queueItemCheckValue,
i,
s,
q;
if (property && property.event) {
if (!Lang.isUndefined(value) && property.validator &&
!property.validator(value)) { // validator
return false;
} else {
if (!Lang.isUndefined(value)) {
property.value = value;
} else {
value = property.value;
}
foundDuplicate = false;
iLen = this.eventQueue.length;
for (i = 0; i < iLen; i++) {
queueItem = this.eventQueue[i];
if (queueItem) {
queueItemKey = queueItem[0];
queueItemValue = queueItem[1];
if (queueItemKey == key) {
/*
found a dupe... push to end of queue, null
current item, and break
*/
this.eventQueue[i] = null;
this.eventQueue.push(
[key, (!Lang.isUndefined(value) ?
value : queueItemValue)]);
foundDuplicate = true;
break;
}
}
}
// this is a refire, or a new property in the queue
if (! foundDuplicate && !Lang.isUndefined(value)) {
this.eventQueue.push([key, value]);
}
}
if (property.supercedes) {
sLen = property.supercedes.length;
for (s = 0; s < sLen; s++) {
supercedesCheck = property.supercedes[s];
qLen = this.eventQueue.length;
for (q = 0; q < qLen; q++) {
queueItemCheck = this.eventQueue[q];
if (queueItemCheck) {
queueItemCheckKey = queueItemCheck[0];
queueItemCheckValue = queueItemCheck[1];
if (queueItemCheckKey ==
supercedesCheck.toLowerCase() ) {
this.eventQueue.push([queueItemCheckKey,
queueItemCheckValue]);
this.eventQueue[q] = null;
break;
}
}
}
}
}
YAHOO.log("Config event queue: " + this.outputEventQueue(), "info", "Config");
return true;
} else {
return false;
}
},
/**
* Fires the event for a property using the property's current value.
* @method refireEvent
* @param {String} key The name of the property
*/
refireEvent: function (key) {
key = key.toLowerCase();
var property = this.config[key];
if (property && property.event &&
!Lang.isUndefined(property.value)) {
if (this.queueInProgress) {
this.queueProperty(key);
} else {
this.fireEvent(key, property.value);
}
}
},
/**
* Applies a key-value Object literal to the configuration, replacing
* any existing values, and queueing the property events.
* Although the values will be set, fireQueue() must be called for their
* associated events to execute.
* @method applyConfig
* @param {Object} userConfig The configuration Object literal
* @param {Boolean} init When set to true, the initialConfig will
* be set to the userConfig passed in, so that calling a reset will
* reset the properties to the passed values.
*/
applyConfig: function (userConfig, init) {
var sKey,
oConfig;
if (init) {
oConfig = {};
for (sKey in userConfig) {
if (Lang.hasOwnProperty(userConfig, sKey)) {
oConfig[sKey.toLowerCase()] = userConfig[sKey];
}
}
this.initialConfig = oConfig;
}
for (sKey in userConfig) {
if (Lang.hasOwnProperty(userConfig, sKey)) {
this.queueProperty(sKey, userConfig[sKey]);
}
}
},
/**
* Refires the events for all configuration properties using their
* current values.
* @method refresh
*/
refresh: function () {
var prop;
for (prop in this.config) {
if (Lang.hasOwnProperty(this.config, prop)) {
this.refireEvent(prop);
}
}
},
/**
* Fires the normalized list of queued property change events
* @method fireQueue
*/
fireQueue: function () {
var i,
queueItem,
key,
value,
property;
this.queueInProgress = true;
for (i = 0;i < this.eventQueue.length; i++) {
queueItem = this.eventQueue[i];
if (queueItem) {
key = queueItem[0];
value = queueItem[1];
property = this.config[key];
property.value = value;
// Clear out queue entry, to avoid it being
// re-added to the queue by any queueProperty/supercedes
// calls which are invoked during fireEvent
this.eventQueue[i] = null;
this.fireEvent(key,value);
}
}
this.queueInProgress = false;
this.eventQueue = [];
},
/**
* Subscribes an external handler to the change event for any
* given property.
* @method subscribeToConfigEvent
* @param {String} key The property name
* @param {Function} handler The handler function to use subscribe to
* the property's event
* @param {Object} obj The Object to use for scoping the event handler
* (see CustomEvent documentation)
* @param {Boolean} overrideContext Optional. If true, will override
* "this" within the handler to map to the scope Object passed into the
* method.
* @return {Boolean} True, if the subscription was successful,
* otherwise false.
*/
subscribeToConfigEvent: function (key, handler, obj, overrideContext) {
var property = this.config[key.toLowerCase()];
if (property && property.event) {
if (!Config.alreadySubscribed(property.event, handler, obj)) {
property.event.subscribe(handler, obj, overrideContext);
}
return true;
} else {
return false;
}
},
/**
* Unsubscribes an external handler from the change event for any
* given property.
* @method unsubscribeFromConfigEvent
* @param {String} key The property name
* @param {Function} handler The handler function to use subscribe to
* the property's event
* @param {Object} obj The Object to use for scoping the event
* handler (see CustomEvent documentation)
* @return {Boolean} True, if the unsubscription was successful,
* otherwise false.
*/
unsubscribeFromConfigEvent: function (key, handler, obj) {
var property = this.config[key.toLowerCase()];
if (property && property.event) {
return property.event.unsubscribe(handler, obj);
} else {
return false;
}
},
/**
* Returns a string representation of the Config object
* @method toString
* @return {String} The Config object in string format.
*/
toString: function () {
var output = "Config";
if (this.owner) {
output += " [" + this.owner.toString() + "]";
}
return output;
},
/**
* Returns a string representation of the Config object's current
* CustomEvent queue
* @method outputEventQueue
* @return {String} The string list of CustomEvents currently queued
* for execution
*/
outputEventQueue: function () {
var output = "",
queueItem,
q,
nQueue = this.eventQueue.length;
for (q = 0; q < nQueue; q++) {
queueItem = this.eventQueue[q];
if (queueItem) {
output += queueItem[0] + "=" + queueItem[1] + ", ";
}
}
return output;
},
/**
* Sets all properties to null, unsubscribes all listeners from each
* property's change event and all listeners from the configChangedEvent.
* @method destroy
*/
destroy: function () {
var oConfig = this.config,
sProperty,
oProperty;
for (sProperty in oConfig) {
if (Lang.hasOwnProperty(oConfig, sProperty)) {
oProperty = oConfig[sProperty];
oProperty.event.unsubscribeAll();
oProperty.event = null;
}
}
this.configChangedEvent.unsubscribeAll();
this.configChangedEvent = null;
this.owner = null;
this.config = null;
this.initialConfig = null;
this.eventQueue = null;
}
};
/**
* Checks to determine if a particular function/Object pair are already
* subscribed to the specified CustomEvent
* @method YAHOO.util.Config.alreadySubscribed
* @static
* @param {YAHOO.util.CustomEvent} evt The CustomEvent for which to check
* the subscriptions
* @param {Function} fn The function to look for in the subscribers list
* @param {Object} obj The execution scope Object for the subscription
* @return {Boolean} true, if the function/Object pair is already subscribed
* to the CustomEvent passed in
*/
Config.alreadySubscribed = function (evt, fn, obj) {
var nSubscribers = evt.subscribers.length,
subsc,
i;
if (nSubscribers > 0) {
i = nSubscribers - 1;
do {
subsc = evt.subscribers[i];
if (subsc && subsc.obj == obj && subsc.fn == fn) {
return true;
}
}
while (i--);
}
return false;
};
YAHOO.lang.augmentProto(Config, YAHOO.util.EventProvider);
}());