/** @module util */
/**
* Core Object.
*
* @author Alain Pitiot
* @version 3.0.1
* @copyright (c) 2019 Ilixa Ltd. ({@link http://ilixa.com})
* @license Distributed under the terms of the MIT License
*/
import { EventEmitter } from './EventEmitter';
/**
* <p>PsychoObject is the base class for all PsychoJS objects.
* It is responsible for handling attributes.</p>
*
* @class
* @extends EventEmitter
* @param {module:core.PsychoJS} psychoJS - the PsychoJS instance
* @param {string} name - the name of the object (mostly useful for debugging)
*/
export class PsychObject extends EventEmitter {
constructor(psychoJS, name) {
super();
this._psychoJS = psychoJS;
// name:
if (typeof name === 'undefined')
name = this.constructor.name;
this._addAttribute('name', name);
}
/**
* Get the PsychoJS instance.
*
* @public
* @return {PsychoJS} the PsychoJS instance
*/
get psychoJS() { return this._psychoJS; }
/**
* Setter for the PsychoJS attribute.
*
* @public
* @param {PsychoJS} psychoJS - the PsychoJS instance
*/
set psychoJS(psychoJS) {
this._psychoJS = psychoJS;
}
/**
* Set the value of an attribute.
*
* @private
* @param {string} attributeName - the name of the attribute
* @param {object} attributeValue - the value of the attribute
* @param {boolean} [log= false] - whether of not to log
* @param {string} [operation] - the binary operation such that the new value of the attribute is the result of the application of the operation to the current value of the attribute and attributeValue
* @param {boolean} [stealth= false] - whether or not to call the potential attribute setters when setting the value of this attribute
* @return {boolean} whether or not the value of that attribute has changed (false if the attribute
* was not previously set)
*/
_setAttribute(attributeName, attributeValue, log = false, operation = undefined, stealth = false) {
let response = { origin: 'PsychObject.setAttribute', context: 'when setting the attribute of an object' };
if (typeof attributeName == 'undefined')
throw { ...response, error: 'the attribute name cannot be undefined' };
if (typeof attributeValue == 'undefined') {
this._psychoJS.logger.warn('setting the value of attribute: ' + attributeName + ' in PsychObject: ' + this._name + ' as: undefined');
}
// (*) apply operation to old and new values:
if (typeof operation !== 'undefined' && this.hasOwnProperty('_' + attributeName)) {
let oldValue = this['_' + attributeName];
// operations can only be applied to numbers and array of numbers (which can be empty):
if (typeof attributeValue == 'number' || (Array.isArray(attributeValue) && (attributeValue.length == 0 || typeof attributeValue[0] == 'number'))) {
// value is an array:
if (Array.isArray(attributeValue)) {
// old value is also an array
if (Array.isArray(oldValue)) {
if (attributeValue.length !== oldValue.length)
throw { ...response, error: 'old and new value should have the same size when they are both arrays' };
switch (operation) {
case '':
// no change to value;
break;
case '+':
attributeValue = attributeValue.map((v, i) => oldValue[i] + v);
break;
case '*':
attributeValue = attributeValue.map((v, i) => oldValue[i] * v);
break;
case '-':
attributeValue = attributeValue.map((v, i) => oldValue[i] - v);
break;
case '/':
attributeValue = attributeValue.map((v, i) => oldValue[i] / v);
break;
case '**':
attributeValue = attributeValue.map((v, i) => oldValue[i] ** v);
break;
case '%':
attributeValue = attributeValue.map((v, i) => oldValue[i] % v);
break;
default:
throw { ...response, error: 'unsupported operation: ' + operation + ' when setting: ' + attributeName + ' in: ' + this.name };
}
} else
// old value is a scalar
{
switch (operation) {
case '':
// no change to value;
break;
case '+':
attributeValue = attributeValue.map(v => oldValue + v);
break;
case '*':
attributeValue = attributeValue.map(v => oldValue * v);
break;
case '-':
attributeValue = attributeValue.map(v => oldValue - v);
break;
case '/':
attributeValue = attributeValue.map(v => oldValue / v);
break;
case '**':
attributeValue = attributeValue.map(v => oldValue ** v);
break;
case '%':
attributeValue = attributeValue.map(v => oldValue % v);
break;
default:
throw { ...response, error: 'unsupported value: ' + JSON.stringify(attributeValue) + ' for operation: ' + operation + ' when setting: ' + attributeName + ' in: ' + this.name };
}
}
} else
// value is a scalar
{
// old value is an array
if (Array.isArray(oldValue)) {
switch (operation) {
case '':
attributeValue = oldValue.map(v => attributeValue);
break;
case '+':
attributeValue = oldValue.map(v => v + attributeValue);
break;
case '*':
attributeValue = oldValue.map(v => v * attributeValue);
break;
case '-':
attributeValue = oldValue.map(v => v - attributeValue);
break;
case '/':
attributeValue = oldValue.map(v => v / attributeValue);
break;
case '**':
attributeValue = oldValue.map(v => v ** attributeValue);
break;
case '%':
attributeValue = oldValue.map(v => v % attributeValue);
break;
default:
throw { ...response, error: 'unsupported operation: ' + operation + ' when setting: ' + attributeName + ' in: ' + this.name };
}
} else
// old value is a scalar
{
switch (operation) {
case '':
// no change to value;
break;
case '+':
attributeValue = oldValue + attributeValue;
break;
case '*':
attributeValue = oldValue * attributeValue;
break;
case '-':
attributeValue = oldValue - attributeValue;
break;
case '/':
attributeValue = oldValue / attributeValue;
break;
case '**':
attributeValue = oldValue ** attributeValue;
break;
case '%':
attributeValue = oldValue % attributeValue;
break;
default:
throw { ...response, error: 'unsupported value: ' + JSON.stringify(attributeValue) + ' for operation: ' + operation + ' when setting: ' + attributeName + ' in: ' + this.name };
}
}
}
} else
throw { ...response, error: 'operation: ' + operation + ' is invalid for old value: ' + JSON.stringify(oldValue) + ' and new value: ' + JSON.stringify(attributeValue) };
}
// (*) log if appropriate:
if (!stealth && (log || this._autoLog) && (typeof this.win !== 'undefined')) {
const message = this.name + ": " + attributeName + " = " + JSON.stringify(attributeValue);
//this.win.logOnFlip(message, psychoJS.logging.EXP, this);
}
// (*) set the value of the attribute and return whether it has changed:
const previousAttributeValue = this['_' + attributeName];
this['_' + attributeName] = attributeValue;
return (attributeValue !== previousAttributeValue);
}
/**
* Add attributes to this instance (e.g. define setters and getters) and affect values to them.
*
* <p>Notes:
* <ul>
* <li> If the object already has a set<attributeName> method, we do not redefine it,
* and the setter for this attribute calls that method instead of _setAttribute.</li>
* <li> _addAttributes is typically called in the constructor of an object, after
* the call to super (see module:visual.ImageStim for an illustration).</li>
* </ul></p>
*
* @protected
* @param {Object} cls - the class object of the subclass of PsychoObject whose attributes we will set
* @param {...*} [args] - the values for the attributes (this also determines which attributes will be set)
*
*/
_addAttributes(cls, ...args) {
// (*) look for the line in the subclass constructor where addAttributes is called
// and extract its arguments:
let callLine = cls.toString().match(/this.*\._addAttributes\(.*\;/)[0];
let startIndex = callLine.indexOf('._addAttributes(') + 16;
let endIndex = callLine.indexOf(');');
let callArgs = callLine.substr(startIndex, endIndex - startIndex).split(',').map((s) => s.trim());
// (*) add (argument name, argument value) pairs to the attribute map:
let attributeMap = new Map();
for (var i = 1; i < callArgs.length; ++i)
attributeMap.set(callArgs[i], args[i - 1]);
// (*) set the value, define the get/set<attributeName> properties and define the getter and setter:
for (let [name, value] of attributeMap.entries())
this._addAttribute(name, value);
}
/**
* Add an attribute to this instance (e.g. define setters and getters) and affect a value to it.
*
* @protected
* @param {string} name - the name of the attribute
* @param {object} value - the value of the attribute
*/
_addAttribute(name, value) {
let getPropertyName = 'get' + name[0].toUpperCase() + name.substr(1);
if (typeof this[getPropertyName] === 'undefined')
this[getPropertyName] = () => this['_' + name];
let setPropertyName = 'set' + name[0].toUpperCase() + name.substr(1);
if (typeof this[setPropertyName] === 'undefined')
this[setPropertyName] = (value, log = false) => {
this._setAttribute(name, value, log);
};
Object.defineProperty(this, name, {
configurable: true,
get() { return this[getPropertyName](); /* return this['_' + name];*/ },
set(value) { this[setPropertyName](value); }
});
// note: we use this[name] instead of this['_' + name] since a this.set<Name> method may available
// in the object, in which case we need to call it
this[name] = value;
//this['_' + name] = value;
}
}