Property Finder - a Cross-Platform HTML5 Mobile App

/// <reference path="..//intellisense.js" />

/*global ko, $, window */

function hydrateObject(state) {
  /// <summary>
  /// Takes a JSON representation of view model state and creates view model instances
  /// via their constructor function as indicated by the 'factoryName' property.
  /// </summary>

  // if state is a primitive type, rather than an object - no 
  // need to hydrate;
  if (!(state instanceof Object)) {
    return state;
  }

  var property, unwrapped, propertyValue,
  // create the required view model instance
    viewModel = new window["ViewModel"][state.factoryName]();

  // iterate over each state property
  for (property in state) {
    if (property === "template" ||
        property === "factoryName" ||
        property === undefined) {
      continue;
    }

    propertyValue = state[property];

    // if the view model property is a function - it might be a KO observable
    if (viewModel[property] instanceof Function) {

      // check if this is a KO observable
      unwrapped = ko.utils.unwrapObservable(viewModel[property]);

      // if after unwrapping we do not get the same object back, then
      // this is an observable
      if (viewModel[property] !== unwrapped) {

        // check if this is an array observable
        if (unwrapped instanceof Array) {
          $.each(propertyValue, function () {
            viewModel[property].push(hydrateObject(this));
          });
        } else {
          // otherwise set the value via the observable setter
          viewModel[property](propertyValue);
        }
      }

    } else {
      viewModel[property] = hydrateObject(propertyValue);
    }
  }

  return viewModel;
}