text: /* Copyright 2017 Mozilla Foundation
   *
   * 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.
   */
  'use strict';
  
  Object.defineProperty(exports, "__esModule", {
    value: true
  });
  exports.validateRangeRequestCapabilities = undefined;
  
  var _util = require('../shared/util');
  
  function validateRangeRequestCapabilities(_ref) {
    var getResponseHeader = _ref.getResponseHeader,
        isHttp = _ref.isHttp,
        rangeChunkSize = _ref.rangeChunkSize,
        disableRange = _ref.disableRange;
  
    (0, _util.assert)(rangeChunkSize > 0);
    var returnValues = {
      allowRangeRequests: false,
      suggestedLength: undefined
    };
    if (disableRange || !isHttp) {
      return returnValues;
    }
    if (getResponseHeader('Accept-Ranges') !== 'bytes') {
      return returnValues;
    }
    var contentEncoding = getResponseHeader('Content-Encoding') || 'identity';
    if (contentEncoding !== 'identity') {
      return returnValues;
    }
    var length = getResponseHeader('Content-Length');
    length = parseInt(length, 10);
    if (!(0, _util.isInt)(length)) {
      return returnValues;
    }
    returnValues.suggestedLength = length;
    if (length <= 2 * rangeChunkSize) {
      return returnValues;
    }
    returnValues.allowRangeRequests = true;
    return returnValues;
  }
  exports.validateRangeRequestCapabilities = validateRangeRequestCapabilities;