Automatically redirects to the daily sales page with preselected categories
As of
// ==UserScript==
// @name Amazon Category Selector
// @namespace https://lewisch.io/
// @version 1.0
// @description Automatically redirects to the daily sales page with preselected categories
// @author Thomas Lewisch
// @match *.amazon.de/gp/angebote*
// @require https://code.jquery.com/jquery-2.2.0.min.js
// @grant none
// ==/UserScript==
/* jshint -W097 */
'use strict';
var CategorySelector = function(options) {
this.options = options || {};
this.defaults = {
url: 'http://www.amazon.de/gp/angebote', // the base url for daily offers,
sortOrder: 'BY_SCORE', // the sort order for displaying the offers
categories: [ // the category-ids to auto-select
340843031, // pc
300992, // games
284266, // movies
562066, // electronics
],
keys: { // the keys to use for building the url
base: 'gb_f_GB-SUPPLE', // the base query string argument used by amazon
sortOrder: 'sortOrder', // the key for the sort order
categories: 'enforcedCategories', // the key for the categories
},
concatenators: { // the concatenators to concatenate the different parts of the url
qs: '?', // the concatentor for the query string
kv: ':', // the key-value concatenator for different arguments
ba: '=', // the base-arguments concatentator for the base key to the other arguments
args: ',', // the arguments concatentator for joining various arguments
values: '%252C', // the concatentor for the values of a single argument
},
selectors: { // the selectors used to find the categories
categoryContainer: '#widgetFilters', // the selector for the category container
activeCategories: ':checkbox:checked', // the selector for the active categories
},
};
this.settings = jQuery.extend({}, this.defaults, options);
};
/**
* starts the category selector
*
* @return {void}
*/
CategorySelector.prototype.run = function () {
var self = this,
exists = window.setInterval(function() {
if (self.filters().length) {
self.redirectIfNecessary();
window.clearInterval(exists);
}
}, 100);
};
/**
* redirects the browser to the filtered
* daily offers page if necessary
*
* @return {void}
*/
CategorySelector.prototype.redirectIfNecessary = function () {
if (this.hasActiveCategories()) {
return;
}
window.location.replace(this.buildUrl());
};
/**
* builds the url to redirect to
*
* @return {string}
*/
CategorySelector.prototype.buildUrl = function () {
var args = [];
if (! this.hasSettings()) {
return this.settings.url;
}
if (this.hasSortOrder()) {
args.push(this.settings.keys.sortOrder + this.settings.concatenators.kv + this.settings.sortOrder);
}
if (this.hasCategories()) {
args.push(this.settings.keys.categories + this.settings.concatenators.kv + this.buildCategoryString());
}
return this.settings.url +
this.settings.concatenators.qs +
this.settings.keys.base +
this.settings.concatenators.ba +
args.join(this.settings.concatenators.args);
};
/**
* gets the active categories
*
* @return {jQuery element|array}
*/
CategorySelector.prototype.activeCategories = function () {
return this.filters().find(this.settings.selectors.activeCategories);
};
/**
* checks if categories are currently active
*
* @return {boolean}
*/
CategorySelector.prototype.hasActiveCategories = function () {
return this.activeCategories().length > 0;
};
/**
* checks if settings have been supplied to
* build a custom url and redirect
*
* @return {boolean}
*/
CategorySelector.prototype.hasSettings = function () {
return this.hasSortOrder() || this.hasCategories();
};
/**
* checks of a sort order has been supplied
*
* @return {boolean}
*/
CategorySelector.prototype.hasSortOrder = function () {
return this.settings.sortOrder !== false && this.settings.sortOrder !== null;
};
/**
* checks if categories have been supplied
*
* @return {boolean}
*/
CategorySelector.prototype.hasCategories = function () {
return jQuery.isArray(this.settings.categories) && this.settings.categories.length > 0;
};
/**
* builds the category string for the url
*
* @return {string}
*/
CategorySelector.prototype.buildCategoryString = function () {
return this.settings.categories.join(this.settings.concatenators.values);
};
/**
* gets the container element that holds the filters
*
* @return {jQuery element|array}
*/
CategorySelector.prototype.filters = function () {
return jQuery(document).find(this.settings.selectors.categoryContainer);
};
/**
* initializes a new category selector
*
* @param {Object} options
* @return {CategorySelector}
*/
CategorySelector.init = function(options) {
var selector = new CategorySelector(options);
selector.run();
return selector;
};
jQuery(document).ready(function($) {
CategorySelector.init();
});