escher-vis/js/src/CallbackManager.js

Escher: A Web Application for Building, Sharing, and Embedding Data-Rich Visualizations of Biological Pathways

/** CallbackManager */

var utils = require('./utils');
var _ = require('underscore');


var CallbackManager = utils.make_class();
CallbackManager.prototype = {
    init: init,
    set: set,
    remove: remove,
    run: run
};
module.exports = CallbackManager;


function init() {

}


function set(name, fn) {
    /** As in d3 callbacks, you can namespace your callbacks after a period:

     select_metabolite.direction_arrow
     select_metabolite.input

     Both are called by select_metabolite


     TODO add *arguments to set, as in _.defer()

     */
    if (this.callbacks===undefined) this.callbacks = {};
    if (this.callbacks[name]===undefined) this.callbacks[name] = [];
    this.callbacks[name].push(fn);

    return this;
}


function remove(name) {
    /** Remove a callback by name

     */
    if (this.callbacks===undefined || Object.keys(this.callbacks).length==0) {
        console.warn('No callbacks to remove');
    }
    delete this.callbacks[name];
    return this;
}


function run(name, this_arg) {
    /** Run all callbacks that match the portion of name before the period ('.').

     Arguments
     ---------

     name: The callback name, which can include a tag after a '.' to
     specificy a particular callback.

     this_arg: (Optional, Default: null) The object assigned to `this` in
     the callback.

     */
    if (_.isUndefined(this.callbacks)) return this;
    if (_.isUndefined(this_arg)) this_arg = null;
    // pass all but the first (name) argument to the callback
    var pass_args = Array.prototype.slice.call(arguments, 2);
    // look for matching callback names
    for (var a_name in this.callbacks) {
        var split_name = a_name.split('.')[0];
        if (split_name==name) {
            this.callbacks[a_name].forEach(function(fn) {
                fn.apply(this_arg, pass_args);
            });
        }
    }
    return this;
}