import {

PostMessageBus,

PostMessageBusSink,

PostMessageBusSource

} from 'angular2/src/web_workers/shared/post_message_bus';

import {MessageBus} from 'angular2/src/web_workers/shared/message_bus';

import {APP_INITIALIZER} from 'angular2/core';

import {Injector, Injectable, Provider} from 'angular2/src/core/di';

import {MessageBasedRenderer} from 'angular2/src/web_workers/ui/renderer';

import {MessageBasedXHRImpl} from 'angular2/src/web_workers/ui/xhr_impl';

import {

WORKER_RENDER_APPLICATION_COMMON,

WORKER_RENDER_MESSAGING_PROVIDERS,

WORKER_SCRIPT,

initializeGenericWorkerRenderer

} from 'angular2/src/platform/worker_render_common';

import {BaseException} from 'angular2/src/facade/exceptions';

/**

* Wrapper class that exposes the Worker

* and underlying {@link MessageBus} for lower level message passing.

*/

@Injectable()

export class WebWorkerInstance {

public worker: Worker;

public bus: MessageBus;

/** @internal */

public init(worker: Worker, bus: MessageBus) {

this.worker = worker;

this.bus = bus;

}

}

/**

* An array of providers that should be passed into `application()` when initializing a new Worker.

*/

export const WORKER_RENDER_APPLICATION: Array<any /*Type | Provider | any[]*/> = /*@ts2dart_const*/[

WORKER_RENDER_APPLICATION_COMMON, WebWorkerInstance,

/*@ts2dart_Provider*/ {

provide: APP_INITIALIZER,

useFactory: (injector => () => initWebWorkerApplication(injector)),

multi: true,

deps: [Injector]

},

/*@ts2dart_Provider*/ {

provide: MessageBus,

useFactory: (instance) => instance.bus,

deps: [WebWorkerInstance]

}

];

function initWebWorkerApplication(injector: Injector): void {

var scriptUri: string;

try {

scriptUri = injector.get(WORKER_SCRIPT);

} catch (e) {

throw new BaseException(

"You must provide your WebWorker's initialization script with the WORKER_SCRIPT token");

}

let instance = injector.get(WebWorkerInstance);

spawnWebWorker(scriptUri, instance);

initializeGenericWorkerRenderer(injector);

}

/**

* Spawns a new class and initializes the WebWorkerInstance

*/

function spawnWebWorker(uri: string, instance: WebWorkerInstance): void {

var webWorker: Worker = new Worker(uri);

var sink = new PostMessageBusSink(webWorker);

var source = new PostMessageBusSource(webWorker);

var bus = new PostMessageBus(sink, source);

instance.init(webWorker, bus);

}