michael@0: /* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
michael@0: /* Copyright 2012 Mozilla Foundation
michael@0:  *
michael@0:  * Licensed under the Apache License, Version 2.0 (the "License");
michael@0:  * you may not use this file except in compliance with the License.
michael@0:  * You may obtain a copy of the License at
michael@0:  *
michael@0:  *     http://www.apache.org/licenses/LICENSE-2.0
michael@0:  *
michael@0:  * Unless required by applicable law or agreed to in writing, software
michael@0:  * distributed under the License is distributed on an "AS IS" BASIS,
michael@0:  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
michael@0:  * See the License for the specific language governing permissions and
michael@0:  * limitations under the License.
michael@0:  */
michael@0: 
michael@0: // NOTE: Be careful what goes in this file, as it is also used from the context
michael@0: // of the addon. So using warn/error in here will break the addon.
michael@0: 
michael@0: 'use strict';
michael@0: 
michael@0: 
michael@0:   
michael@0:   Components.utils.import('resource://gre/modules/Services.jsm');
michael@0:   
michael@0:   var EXPORTED_SYMBOLS = ['NetworkManager'];
michael@0:   
michael@0:   var console = {
michael@0:     log: function console_log(aMsg) {
michael@0:       var msg = 'network.js: ' + (aMsg.join ? aMsg.join('') : aMsg);
michael@0:       Services.console.logStringMessage(msg);
michael@0:       // TODO(mack): dump() doesn't seem to work here...
michael@0:       dump(msg + '\n');
michael@0:     }
michael@0:   }
michael@0: 
michael@0: var NetworkManager = (function NetworkManagerClosure() {
michael@0: 
michael@0:   var OK_RESPONSE = 200;
michael@0:   var PARTIAL_CONTENT_RESPONSE = 206;
michael@0: 
michael@0:   function NetworkManager(url, args) {
michael@0:     this.url = url;
michael@0:     args = args || {};
michael@0:     this.isHttp = /^https?:/i.test(url);
michael@0:     this.httpHeaders = (this.isHttp && args.httpHeaders) || {};
michael@0:     this.withCredentials = args.withCredentials || false;
michael@0:     this.getXhr = args.getXhr ||
michael@0:       function NetworkManager_getXhr() {
michael@0:         return new XMLHttpRequest();
michael@0:       };
michael@0: 
michael@0:     this.currXhrId = 0;
michael@0:     this.pendingRequests = {};
michael@0:     this.loadedRequests = {};
michael@0:   }
michael@0: 
michael@0:   function getArrayBuffer(xhr) {
michael@0:     var data = (xhr.mozResponseArrayBuffer || xhr.mozResponse ||
michael@0:                 xhr.responseArrayBuffer || xhr.response);
michael@0:     if (typeof data !== 'string') {
michael@0:       return data;
michael@0:     }
michael@0:     var length = data.length;
michael@0:     var buffer = new Uint8Array(length);
michael@0:     for (var i = 0; i < length; i++) {
michael@0:       buffer[i] = data.charCodeAt(i) & 0xFF;
michael@0:     }
michael@0:     return buffer;
michael@0:   }
michael@0: 
michael@0:   NetworkManager.prototype = {
michael@0:     requestRange: function NetworkManager_requestRange(begin, end, listeners) {
michael@0:       var args = {
michael@0:         begin: begin,
michael@0:         end: end
michael@0:       };
michael@0:       for (var prop in listeners) {
michael@0:         args[prop] = listeners[prop];
michael@0:       }
michael@0:       return this.request(args);
michael@0:     },
michael@0: 
michael@0:     requestFull: function NetworkManager_requestRange(listeners) {
michael@0:       return this.request(listeners);
michael@0:     },
michael@0: 
michael@0:     request: function NetworkManager_requestRange(args) {
michael@0:       var xhr = this.getXhr();
michael@0:       var xhrId = this.currXhrId++;
michael@0:       var pendingRequest = this.pendingRequests[xhrId] = {
michael@0:         xhr: xhr
michael@0:       };
michael@0: 
michael@0:       xhr.open('GET', this.url);
michael@0:       xhr.withCredentials = this.withCredentials;
michael@0:       for (var property in this.httpHeaders) {
michael@0:         var value = this.httpHeaders[property];
michael@0:         if (typeof value === 'undefined') {
michael@0:           continue;
michael@0:         }
michael@0:         xhr.setRequestHeader(property, value);
michael@0:       }
michael@0:       if (this.isHttp && 'begin' in args && 'end' in args) {
michael@0:         var rangeStr = args.begin + '-' + (args.end - 1);
michael@0:         xhr.setRequestHeader('Range', 'bytes=' + rangeStr);
michael@0:         pendingRequest.expectedStatus = 206;
michael@0:       } else {
michael@0:         pendingRequest.expectedStatus = 200;
michael@0:       }
michael@0: 
michael@0:       xhr.mozResponseType = xhr.responseType = 'arraybuffer';
michael@0: 
michael@0:       if (args.onProgress) {
michael@0:         xhr.onprogress = args.onProgress;
michael@0:       }
michael@0:       if (args.onError) {
michael@0:         xhr.onerror = function(evt) {
michael@0:           args.onError(xhr.status);
michael@0:         };
michael@0:       }
michael@0:       xhr.onreadystatechange = this.onStateChange.bind(this, xhrId);
michael@0: 
michael@0:       pendingRequest.onHeadersReceived = args.onHeadersReceived;
michael@0:       pendingRequest.onDone = args.onDone;
michael@0:       pendingRequest.onError = args.onError;
michael@0: 
michael@0:       xhr.send(null);
michael@0: 
michael@0:       return xhrId;
michael@0:     },
michael@0: 
michael@0:     onStateChange: function NetworkManager_onStateChange(xhrId, evt) {
michael@0:       var pendingRequest = this.pendingRequests[xhrId];
michael@0:       if (!pendingRequest) {
michael@0:         // Maybe abortRequest was called...
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       var xhr = pendingRequest.xhr;
michael@0:       if (xhr.readyState >= 2 && pendingRequest.onHeadersReceived) {
michael@0:         pendingRequest.onHeadersReceived();
michael@0:         delete pendingRequest.onHeadersReceived;
michael@0:       }
michael@0: 
michael@0:       if (xhr.readyState !== 4) {
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       if (!(xhrId in this.pendingRequests)) {
michael@0:         // The XHR request might have been aborted in onHeadersReceived()
michael@0:         // callback, in which case we should abort request
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       delete this.pendingRequests[xhrId];
michael@0: 
michael@0:       // success status == 0 can be on ftp, file and other protocols
michael@0:       if (xhr.status === 0 && this.isHttp) {
michael@0:         if (pendingRequest.onError) {
michael@0:           pendingRequest.onError(xhr.status);
michael@0:         }
michael@0:         return;
michael@0:       }
michael@0:       var xhrStatus = xhr.status || OK_RESPONSE;
michael@0: 
michael@0:       // From http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.35.2:
michael@0:       // "A server MAY ignore the Range header". This means it's possible to
michael@0:       // get a 200 rather than a 206 response from a range request.
michael@0:       var ok_response_on_range_request =
michael@0:           xhrStatus === OK_RESPONSE &&
michael@0:           pendingRequest.expectedStatus === PARTIAL_CONTENT_RESPONSE;
michael@0: 
michael@0:       if (!ok_response_on_range_request &&
michael@0:           xhrStatus !== pendingRequest.expectedStatus) {
michael@0:         if (pendingRequest.onError) {
michael@0:           pendingRequest.onError(xhr.status);
michael@0:         }
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       this.loadedRequests[xhrId] = true;
michael@0: 
michael@0:       var chunk = getArrayBuffer(xhr);
michael@0:       if (xhrStatus === PARTIAL_CONTENT_RESPONSE) {
michael@0:         var rangeHeader = xhr.getResponseHeader('Content-Range');
michael@0:         var matches = /bytes (\d+)-(\d+)\/(\d+)/.exec(rangeHeader);
michael@0:         var begin = parseInt(matches[1], 10);
michael@0:         pendingRequest.onDone({
michael@0:           begin: begin,
michael@0:           chunk: chunk
michael@0:         });
michael@0:       } else {
michael@0:         pendingRequest.onDone({
michael@0:           begin: 0,
michael@0:           chunk: chunk
michael@0:         });
michael@0:       }
michael@0:     },
michael@0: 
michael@0:     hasPendingRequests: function NetworkManager_hasPendingRequests() {
michael@0:       for (var xhrId in this.pendingRequests) {
michael@0:         return true;
michael@0:       }
michael@0:       return false;
michael@0:     },
michael@0: 
michael@0:     getRequestXhr: function NetworkManager_getXhr(xhrId) {
michael@0:       return this.pendingRequests[xhrId].xhr;
michael@0:     },
michael@0: 
michael@0:     isPendingRequest: function NetworkManager_isPendingRequest(xhrId) {
michael@0:       return xhrId in this.pendingRequests;
michael@0:     },
michael@0: 
michael@0:     isLoadedRequest: function NetworkManager_isLoadedRequest(xhrId) {
michael@0:       return xhrId in this.loadedRequests;
michael@0:     },
michael@0: 
michael@0:     abortAllRequests: function NetworkManager_abortAllRequests() {
michael@0:       for (var xhrId in this.pendingRequests) {
michael@0:         this.abortRequest(xhrId | 0);
michael@0:       }
michael@0:     },
michael@0: 
michael@0:     abortRequest: function NetworkManager_abortRequest(xhrId) {
michael@0:       var xhr = this.pendingRequests[xhrId].xhr;
michael@0:       delete this.pendingRequests[xhrId];
michael@0:       xhr.abort();
michael@0:     }
michael@0:   };
michael@0: 
michael@0:   return NetworkManager;
michael@0: })();
michael@0: 
michael@0: