<!--
@license
Copyright (C) 2018 The Android Open Source Project

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<script>
(function(window) {
  'use strict';

  window.Gerrit = window.Gerrit || {};

  /** @polymerBehavior Gerrit.SafeTypes */
  Gerrit.SafeTypes = {};

  const SAFE_URL_PATTERN = /^(https?:\/\/|mailto:|\/|#)/i;

  /**
   * Wraps a string to be used as a URL. An error is thrown if the string cannot
   * be considered safe.
   * @constructor
   * @param {string} url the unwrapped, potentially unsafe URL.
   */
  Gerrit.SafeTypes.SafeUrl = function(url) {
    if (!SAFE_URL_PATTERN.test(url)) {
      throw new Error(`URL not marked as safe: ${url}`);
    }
    this._url = url;
  };

  /**
   * Get the string representation of the safe URL.
   * @returns {string}
   */
  Gerrit.SafeTypes.SafeUrl.prototype.asString = function() {
    return this._url;
  };

  Gerrit.SafeTypes.safeTypesBridge = function(value, type) {
    // If the value is being bound to a URL, ensure the value is wrapped in the
    // SafeUrl type first. If the URL is not safe, allow the SafeUrl constructor
    // to surface the error.
    if (type === 'URL') {
      let safeValue = null;
      if (value instanceof Gerrit.SafeTypes.SafeUrl) {
        safeValue = value;
      } else if (typeof value === 'string') {
        safeValue = new Gerrit.SafeTypes.SafeUrl(value);
      }
      if (safeValue) {
        return safeValue.asString();
      }
    }

    // If the value is being bound to a string or a constant, then the string
    // can be used as is.
    if (type === 'STRING' || type === 'CONSTANT') {
      return value;
    }

    // Otherwise fail.
    throw new Error(`Refused to bind value as ${type}: ${value}`);
  };
})(window);
</script>