this.workbox = this.workbox || {}; this.workbox.rangeRequests = (function (exports, WorkboxError_js, assert_js, logger_js) {

'use strict';

try {
  self['workbox:range-requests:5.1.4'] && _();
} catch (e) {}

/*
  Copyright 2018 Google LLC

  Use of this source code is governed by an MIT-style
  license that can be found in the LICENSE file or at
  https://opensource.org/licenses/MIT.
*/
/**
 * @param {Blob} blob A source blob.
 * @param {number} [start] The offset to use as the start of the
 * slice.
 * @param {number} [end] The offset to use as the end of the slice.
 * @return {Object} An object with `start` and `end` properties, reflecting
 * the effective boundaries to use given the size of the blob.
 *
 * @private
 */

function calculateEffectiveBoundaries(blob, start, end) {
  {
    assert_js.assert.isInstance(blob, Blob, {
      moduleName: 'workbox-range-requests',
      funcName: 'calculateEffectiveBoundaries',
      paramName: 'blob'
    });
  }

  const blobSize = blob.size;

  if (end && end > blobSize || start && start < 0) {
    throw new WorkboxError_js.WorkboxError('range-not-satisfiable', {
      size: blobSize,
      end,
      start
    });
  }

  let effectiveStart;
  let effectiveEnd;

  if (start !== undefined && end !== undefined) {
    effectiveStart = start; // Range values are inclusive, so add 1 to the value.

    effectiveEnd = end + 1;
  } else if (start !== undefined && end === undefined) {
    effectiveStart = start;
    effectiveEnd = blobSize;
  } else if (end !== undefined && start === undefined) {
    effectiveStart = blobSize - end;
    effectiveEnd = blobSize;
  }

  return {
    start: effectiveStart,
    end: effectiveEnd
  };
}

/*
  Copyright 2018 Google LLC

  Use of this source code is governed by an MIT-style
  license that can be found in the LICENSE file or at
  https://opensource.org/licenses/MIT.
*/
/**
 * @param {string} rangeHeader A Range: header value.
 * @return {Object} An object with `start` and `end` properties, reflecting
 * the parsed value of the Range: header. If either the `start` or `end` are
 * omitted, then `null` will be returned.
 *
 * @private
 */

function parseRangeHeader(rangeHeader) {
  {
    assert_js.assert.isType(rangeHeader, 'string', {
      moduleName: 'workbox-range-requests',
      funcName: 'parseRangeHeader',
      paramName: 'rangeHeader'
    });
  }

  const normalizedRangeHeader = rangeHeader.trim().toLowerCase();

  if (!normalizedRangeHeader.startsWith('bytes=')) {
    throw new WorkboxError_js.WorkboxError('unit-must-be-bytes', {
      normalizedRangeHeader
    });
  } // Specifying multiple ranges separate by commas is valid syntax, but this
  // library only attempts to handle a single, contiguous sequence of bytes.
  // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Range#Syntax

  if (normalizedRangeHeader.includes(',')) {
    throw new WorkboxError_js.WorkboxError('single-range-only', {
      normalizedRangeHeader
    });
  }

  const rangeParts = /(\d*)-(\d*)/.exec(normalizedRangeHeader); // We need either at least one of the start or end values.

  if (!rangeParts || !(rangeParts[1] || rangeParts[2])) {
    throw new WorkboxError_js.WorkboxError('invalid-range-values', {
      normalizedRangeHeader
    });
  }

  return {
    start: rangeParts[1] === '' ? undefined : Number(rangeParts[1]),
    end: rangeParts[2] === '' ? undefined : Number(rangeParts[2])
  };
}

/*
  Copyright 2018 Google LLC

  Use of this source code is governed by an MIT-style
  license that can be found in the LICENSE file or at
  https://opensource.org/licenses/MIT.
*/
/**
 * Given a `Request` and `Response` objects as input, this will return a
 * promise for a new `Response`.
 *
 * If the original `Response` already contains partial content (i.e. it has
 * a status of 206), then this assumes it already fulfills the `Range:`
 * requirements, and will return it as-is.
 *
 * @param {Request} request A request, which should contain a Range:
 * header.
 * @param {Response} originalResponse A response.
 * @return {Promise<Response>} Either a `206 Partial Content` response, with
 * the response body set to the slice of content specified by the request's
 * `Range:` header, or a `416 Range Not Satisfiable` response if the
 * conditions of the `Range:` header can't be met.
 *
 * @memberof module:workbox-range-requests
 */

async function createPartialResponse(request, originalResponse) {
  try {
    if ("dev" !== 'production') {
      assert_js.assert.isInstance(request, Request, {
        moduleName: 'workbox-range-requests',
        funcName: 'createPartialResponse',
        paramName: 'request'
      });
      assert_js.assert.isInstance(originalResponse, Response, {
        moduleName: 'workbox-range-requests',
        funcName: 'createPartialResponse',
        paramName: 'originalResponse'
      });
    }

    if (originalResponse.status === 206) {
      // If we already have a 206, then just pass it through as-is;
      // see https://github.com/GoogleChrome/workbox/issues/1720
      return originalResponse;
    }

    const rangeHeader = request.headers.get('range');

    if (!rangeHeader) {
      throw new WorkboxError_js.WorkboxError('no-range-header');
    }

    const boundaries = parseRangeHeader(rangeHeader);
    const originalBlob = await originalResponse.blob();
    const effectiveBoundaries = calculateEffectiveBoundaries(originalBlob, boundaries.start, boundaries.end);
    const slicedBlob = originalBlob.slice(effectiveBoundaries.start, effectiveBoundaries.end);
    const slicedBlobSize = slicedBlob.size;
    const slicedResponse = new Response(slicedBlob, {
      // Status code 206 is for a Partial Content response.
      // See https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/206
      status: 206,
      statusText: 'Partial Content',
      headers: originalResponse.headers
    });
    slicedResponse.headers.set('Content-Length', String(slicedBlobSize));
    slicedResponse.headers.set('Content-Range', `bytes ${effectiveBoundaries.start}-${effectiveBoundaries.end - 1}/` + originalBlob.size);
    return slicedResponse;
  } catch (error) {
    {
      logger_js.logger.warn(`Unable to construct a partial response; returning a ` + `416 Range Not Satisfiable response instead.`);
      logger_js.logger.groupCollapsed(`View details here.`);
      logger_js.logger.log(error);
      logger_js.logger.log(request);
      logger_js.logger.log(originalResponse);
      logger_js.logger.groupEnd();
    }

    return new Response('', {
      status: 416,
      statusText: 'Range Not Satisfiable'
    });
  }
}

/*
  Copyright 2018 Google LLC

  Use of this source code is governed by an MIT-style
  license that can be found in the LICENSE file or at
  https://opensource.org/licenses/MIT.
*/
/**
 * The range request plugin makes it easy for a request with a 'Range' header to
 * be fulfilled by a cached response.
 *
 * It does this by intercepting the `cachedResponseWillBeUsed` plugin callback
 * and returning the appropriate subset of the cached response body.
 *
 * @memberof module:workbox-range-requests
 */

class RangeRequestsPlugin {
  constructor() {
    /**
     * @param {Object} options
     * @param {Request} options.request The original request, which may or may not
     * contain a Range: header.
     * @param {Response} options.cachedResponse The complete cached response.
     * @return {Promise<Response>} If request contains a 'Range' header, then a
     * new response with status 206 whose body is a subset of `cachedResponse` is
     * returned. Otherwise, `cachedResponse` is returned as-is.
     *
     * @private
     */
    this.cachedResponseWillBeUsed = async ({
      request,
      cachedResponse
    }) => {
      // Only return a sliced response if there's something valid in the cache,
      // and there's a Range: header in the request.
      if (cachedResponse && request.headers.has('range')) {
        return await createPartialResponse(request, cachedResponse);
      } // If there was no Range: header, or if cachedResponse wasn't valid, just
      // pass it through as-is.

      return cachedResponse;
    };
  }

}

exports.RangeRequestsPlugin = RangeRequestsPlugin;
exports.createPartialResponse = createPartialResponse;

return exports;

}({}, workbox.core._private, workbox.core._private, workbox.core._private)); //# sourceMappingURL=workbox-range-requests.dev.js.map