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- 'use strict';
-
- var external = require("./external");
- var DataWorker = require('./stream/DataWorker');
- var DataLengthProbe = require('./stream/DataLengthProbe');
- var Crc32Probe = require('./stream/Crc32Probe');
- var DataLengthProbe = require('./stream/DataLengthProbe');
-
- /**
- * Represent a compressed object, with everything needed to decompress it.
- * @constructor
- * @param {number} compressedSize the size of the data compressed.
- * @param {number} uncompressedSize the size of the data after decompression.
- * @param {number} crc32 the crc32 of the decompressed file.
- * @param {object} compression the type of compression, see lib/compressions.js.
- * @param {String|ArrayBuffer|Uint8Array|Buffer} data the compressed data.
- */
- function CompressedObject(compressedSize, uncompressedSize, crc32, compression, data) {
- this.compressedSize = compressedSize;
- this.uncompressedSize = uncompressedSize;
- this.crc32 = crc32;
- this.compression = compression;
- this.compressedContent = data;
- }
-
- CompressedObject.prototype = {
- /**
- * Create a worker to get the uncompressed content.
- * @return {GenericWorker} the worker.
- */
- getContentWorker : function () {
- var worker = new DataWorker(external.Promise.resolve(this.compressedContent))
- .pipe(this.compression.uncompressWorker())
- .pipe(new DataLengthProbe("data_length"));
-
- var that = this;
- worker.on("end", function () {
- if(this.streamInfo['data_length'] !== that.uncompressedSize) {
- throw new Error("Bug : uncompressed data size mismatch");
- }
- });
- return worker;
- },
- /**
- * Create a worker to get the compressed content.
- * @return {GenericWorker} the worker.
- */
- getCompressedWorker : function () {
- return new DataWorker(external.Promise.resolve(this.compressedContent))
- .withStreamInfo("compressedSize", this.compressedSize)
- .withStreamInfo("uncompressedSize", this.uncompressedSize)
- .withStreamInfo("crc32", this.crc32)
- .withStreamInfo("compression", this.compression)
- ;
- }
- };
-
- /**
- * Chain the given worker with other workers to compress the content with the
- * given compresion.
- * @param {GenericWorker} uncompressedWorker the worker to pipe.
- * @param {Object} compression the compression object.
- * @param {Object} compressionOptions the options to use when compressing.
- * @return {GenericWorker} the new worker compressing the content.
- */
- CompressedObject.createWorkerFrom = function (uncompressedWorker, compression, compressionOptions) {
- return uncompressedWorker
- .pipe(new Crc32Probe())
- .pipe(new DataLengthProbe("uncompressedSize"))
- .pipe(compression.compressWorker(compressionOptions))
- .pipe(new DataLengthProbe("compressedSize"))
- .withStreamInfo("compression", compression);
- };
-
- module.exports = CompressedObject;
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