'use strict';

var jsonReplacer = function(key, value) {
  var val = value;
  if (/^\$+/.test(key)) {
    val = undefined;
  } else if (isWindow(value)) {
    val = '$WINDOW';
  } else if (value &&  document === value) {
    val = '$DOCUMENT';
  } else if (isScope(value)) {
    val = '$SCOPE';
  }

  return val;
};

/**
 * @ngdoc function
 * @name angular.toJson
 * @function
 *
 * @description
 * Serializes input into a JSON-formatted string.
 *
 * @param {Object|Array|Date|string|number} obj Input to be serialized into JSON.
 * @param {boolean=} pretty If set to true, the JSON output will contain newlines and whitespace.
 * @returns {string} Jsonified string representing `obj`.
 */
function toJson(obj, pretty) {
  return JSON.stringify(obj, jsonReplacer, pretty ? '  ' : null);
}

/**
 * @ngdoc function
 * @name angular.fromJson
 * @function
 *
 * @description
 * Deserializes a JSON string.
 *
 * @param {string} json JSON string to deserialize.
 * @returns {Object|Array|Date|string|number} Deserialized thingy.
 */
function fromJson(json) {
  return isString(json)
      ? JSON.parse(json)
      : json;
}