/**
 * Ext.ux.plugins
 *
 * @author    Ing. Jozef Sakáloš <jsakalos@aariadne.com>
 * @copyright (c) 2007, by Ing. Jozef Sakáloš
 * @date      24. November 2007
 * @version   $Id: Ext.ux.plugins.js 596 2007-11-25 13:40:43Z jozo $
 */

Ext.namespace('Ext.ux', 'Ext.ux.plugins');

/**
 * Remote Validator
 * Makes remote (server) field validation easier
 *
 * To be used by form fields like TextField, NubmerField, TextArea, ...
 */
Ext.ux.plugins.RemoteValidator = {
	init:function(field) {
		// save original functions
		var isValid = field.isValid;
		var validate = field.validate;

		// apply remote validation to field
		Ext.apply(field, {
			 remoteValid:false

			// private
			,isValid:function(preventMark) {
				return isValid.call(this, preventMark) && this.remoteValid;
			}

			// private
			,validate:function() {
				var clientValid = validate.call(this);
				if(!this.disabled && !clientValid) {
					return false;
				}
				if(this.disabled || (clientValid && this.remoteValid)) {
					this.clearInvalid();
					return true;
				}
				if(!this.remoteValid) {
					this.markInvalid(this.reason);
					return false;
				}
				return false;
			}

			// private - remote validation request
			,validateRemote:function() {
				this.rvOptions.params = this.rvOptions.params || {};
				this.rvOptions.params.field = this.name;
				this.rvOptions.params.value = this.getValue();
				Ext.Ajax.request(this.rvOptions);
			}

			// private - remote validation request success handler
			,rvSuccess:function(response, options) {
				var o;
				try {
					o = Ext.decode(response.responseText);
				}
				catch(e) {
					throw this.cannotDecodeText;
				}
				if('object' !== typeof o) {
					throw this.notObjectText;
				}
				if(true !== o.success) {
					throw this.serverErrorText + ': ' + o.error;
				}
				var names = this.rvOptions.paramNames;
				this.remoteValid = true === o[names.valid];
				this.reason = o[names.reason];
				this.validate();
			}

			// private - remote validation request failure handler
			,rvFailure:function(response, options) {
				throw this.requestFailText
			}

			// private - runs from keyup event handler
			,filterRemoteValidation:function(e) {
				if(!e.isNavKeyPress()) {
					this.remoteValidationTask.delay(this.remoteValidationDelay);
				}
			}
		});

		// remote validation defaults
		Ext.applyIf(field, {
			 remoteValidationDelay:500
			,reason:'Server has not yet validated the value'
			,cannotDecodeText:'Cannot decode json object'
			,notObjectText:'Server response is not an object'
			,serverErrorText:'Server error'
			,requestFailText:'Server request failed'
		});

		// install event handlers on field render
		field.on({
			render:{single:true, scope:field, fn:function() {
				this.remoteValidationTask = new Ext.util.DelayedTask(this.validateRemote, this);
				this.el.on('keyup', this.filterRemoteValidation, this);
			}}
		});

		// setup remote validation request options
		field.rvOptions = field.rvOptions || {};
		Ext.applyIf(field.rvOptions, {
			 method:'post'
			,scope:field
			,success:field.rvSuccess
			,failure:field.rvFailure
			,paramNames: {
				 valid:'valid'
				,reason:'reason'
			}
		});
	}
};

// end of file