safaribook-knockout-essentials/ko-cart/js/viewmodel.js

"use strict";
var vm = (function () {
  var catalog = ko.observableArray([
    Product(1, "T-Shirt", 10.0, 20),
    Product(2, "Trousers", 20.0, 10),
    Product(3, "Shirt", 15.0, 20),
    Product(4, "Shorts", 5.0, 10),
  ]);

  var newProduct = Product("", "", "", "");
  var clearNewProduct = function () {
    newProduct.name("");
    newProduct.price("");
    newProduct.stock("");
  };

  var addProduct = function (context) {
    var id = new Date().valueOf(); // random id from time

    var product = Product(id, context.name(), context.price(), context.stock());
    catalog.push(product);
    clearNewProduct();
  };

  var searchTerm = ko.observable("");
  var filteredCatalog = ko.computed(function () {
    // if catalog is empty return empty array
    if (!catalog()) {
      return [];
    }
    var filter = searchTerm().toLowerCase();
    // if filter is empty return all the catalog
    if (!filter) {
      return catalog();
    }
    //filter data
    var filtered = ko.utils.arrayFilter(catalog(), function (item) {
      var fields = ["name"]; // we choose to filter by name
      var i = fields.length;
      while (i--) {
        var prop = fields[i];
        var strProp = ko.unwrap(item[prop]).toLocaleLowerCase();
        if (strProp.indexOf(filter) !== -1) {
          return true;
        }
      }
      return false;
    });
    return filtered;
  });

  return {
    searchTerm: searchTerm,
    catalog: filteredCatalog,
    newProduct: newProduct,
    addProduct: addProduct,
  };
})();
ko.applyBindings(vm);