michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: // Code that is shared between clients and workers.
michael@0: this.EXPORTED_SYMBOLS = ["AbstractPort"];
michael@0: 
michael@0: this.AbstractPort = function AbstractPort(portid) {
michael@0:   this._portid = portid;
michael@0:   this._handler = undefined;
michael@0:   this._closed = false;
michael@0:   // pending messages sent to this port before it has a message handler.
michael@0:   this._pendingMessagesIncoming = [];
michael@0: };
michael@0: 
michael@0: AbstractPort.prototype = {
michael@0:   _portType: null, // set by a subclass.
michael@0:   // abstract methods to be overridden.
michael@0:   _dopost: function fw_AbstractPort_dopost(data) {
michael@0:     throw new Error("not implemented");
michael@0:   },
michael@0:   _onerror: function fw_AbstractPort_onerror(err) {
michael@0:     throw new Error("not implemented");
michael@0:   },
michael@0: 
michael@0:   // and concrete methods shared by client and workers.
michael@0:   toString: function fw_AbstractPort_toString() {
michael@0:     return "MessagePort(portType='" + this._portType + "', portId="
michael@0:            + this._portid + (this._closed ? ", closed=true" : "") + ")";
michael@0:   },
michael@0:   _JSONParse: function fw_AbstractPort_JSONParse(data) JSON.parse(data),
michael@0: 
michael@0:  _postControlMessage: function fw_AbstractPort_postControlMessage(topic, data) {
michael@0:     let postData = {
michael@0:       portTopic: topic,
michael@0:       portId: this._portid,
michael@0:       portFromType: this._portType,
michael@0:       data: data
michael@0:     };
michael@0:     this._dopost(postData);
michael@0:   },
michael@0: 
michael@0:   _onmessage: function fw_AbstractPort_onmessage(data) {
michael@0:     // See comments in postMessage below - we work around a cloning
michael@0:     // issue by using JSON for these messages.
michael@0:     // Further, we allow the workers to override exactly how the JSON parsing
michael@0:     // is done - we try and do such parsing in the client window so things
michael@0:     // like prototype overrides on Array work as expected.
michael@0:     if (!this._handler) {
michael@0:       this._pendingMessagesIncoming.push(data);
michael@0:     } else {
michael@0:       data = this._JSONParse(data);
michael@0:       try {
michael@0:         this._handler({
michael@0:           data: data,
michael@0:           __exposedProps__: {
michael@0:             data: 'r'
michael@0:           }
michael@0:         });
michael@0:       } catch (ex) {
michael@0:         this._onerror(ex);
michael@0:       }
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   set onmessage(handler) { // property setter for onmessage
michael@0:     this._handler = handler;
michael@0:     while (this._pendingMessagesIncoming.length) {
michael@0:       this._onmessage(this._pendingMessagesIncoming.shift());
michael@0:     }
michael@0:   },
michael@0:   get onmessage() {
michael@0:     return this._handler;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * postMessage
michael@0:    *
michael@0:    * Send data to the onmessage handler on the other end of the port.  The
michael@0:    * data object should have a topic property.
michael@0:    *
michael@0:    * @param {jsobj} data
michael@0:    */
michael@0:   postMessage: function fw_AbstractPort_postMessage(data) {
michael@0:     if (this._closed) {
michael@0:       throw new Error("port is closed");
michael@0:     }
michael@0:     // There seems to be an issue with passing objects directly and letting
michael@0:     // the structured clone thing work - we sometimes get:
michael@0:     // [Exception... "The object could not be cloned."  code: "25" nsresult: "0x80530019 (DataCloneError)"]
michael@0:     // The best guess is that this happens when funky things have been added to the prototypes.
michael@0:     // It doesn't happen for our "control" messages, only in messages from
michael@0:     // content - so we explicitly use JSON on these messages as that avoids
michael@0:     // the problem.
michael@0:     this._postControlMessage("port-message", JSON.stringify(data));
michael@0:   },
michael@0: 
michael@0:   close: function fw_AbstractPort_close() {
michael@0:     if (this._closed) {
michael@0:       return; // already closed.
michael@0:     }
michael@0:     this._postControlMessage("port-close");
michael@0:     // and clean myself up.
michael@0:     this._handler = null;
michael@0:     this._pendingMessagesIncoming = [];
michael@0:     this._closed = true;
michael@0:   }
michael@0: };