dev@40: /**
dev@40:  * Created by lucas on 01/12/2016.
dev@40:  */
dev@40: 
dev@88: import {PiperVampService, ListRequest, ListResponse} from 'piper';
dev@72: import {
dev@226:   SimpleRequest
dev@72: } from 'piper/HigherLevelUtilities';
dev@44: import { VampExamplePlugins } from 'piper/ext/VampExamplePluginsModule';
dev@243: import {
dev@243:   AvailableLibraries
dev@243: } from './feature-extraction.service';
dev@226: import {
dev@226:   DedicatedWorkerGlobalScope,
dev@226:   WebWorkerStreamingServer
dev@236: } from 'piper/servers/WebWorkerStreamingServer';
dev@226: import {
dev@226:   PiperStreamingService,
dev@226:   StreamingResponse,
dev@226:   StreamingService
dev@236: } from 'piper/StreamingService';
dev@236: import {Observable} from 'rxjs/Observable';
dev@236: import {EmscriptenModule} from 'piper/PiperVampService';
dev@243: import {streamingResponseReducer} from './FeatureReducers';
dev@40: 
dev@40: interface MessageEvent {
dev@40:   readonly data: any;
dev@40: }
dev@40: 
dev@72: type LibraryUri = string;
dev@72: type LibraryKey = string;
dev@72: 
dev@72: type RequireJs = (libs: string[], callback: (...libs: any[]) => void) => void;
dev@72: 
dev@226: class AggregateStreamingService implements StreamingService {
dev@226:   private services: Map<LibraryKey, PiperStreamingService>;
dev@226: 
dev@226:   constructor() {
dev@226:     this.services = new Map<LibraryKey, PiperStreamingService>();
dev@226:     this.services.set(
dev@226:       'vamp-example-plugins',
dev@226:       new PiperStreamingService(new PiperVampService(VampExamplePlugins()))
dev@226:     );
dev@226:   }
dev@226: 
dev@226:   addService(key: LibraryKey, service: PiperStreamingService): void {
dev@226:     this.services.set(key, service);
dev@226:   }
dev@226: 
dev@226:   list(request: ListRequest): Promise<ListResponse> {
dev@226:     return Promise.all(
dev@226:       [...this.services.values()].map(client => client.list({}))
dev@226:     ).then(allAvailable => ({
dev@226:         available: allAvailable.reduce(
dev@226:           (all, current) => all.concat(current.available),
dev@226:           []
dev@226:         )
dev@226:       })
dev@226:     );
dev@226:   }
dev@226: 
dev@226:   process(request: SimpleRequest): Observable<StreamingResponse> {
dev@248:     return this.dispatch('process', request);
dev@226:   }
dev@226: 
dev@226:   collect(request: SimpleRequest): Observable<StreamingResponse> {
dev@248:     return this.dispatch('collect', request);
dev@248:   }
dev@248: 
dev@248:   protected dispatch(method: 'process' | 'collect',
dev@248:                      request: SimpleRequest): Observable<StreamingResponse> {
dev@226:     const key = request.key.split(':')[0];
dev@226:     return this.services.has(key) ?
dev@248:       this.services.get(key)[method](request) : Observable.throw('Invalid key');
dev@226:   }
dev@226: }
dev@226: 
dev@250: class ThrottledReducingAggregateService extends AggregateStreamingService {
dev@243:   constructor() {
dev@243:     super();
dev@243:   }
dev@243: 
dev@248:   protected dispatch(method: 'process' | 'collect',
dev@248:                      request: SimpleRequest): Observable<StreamingResponse> {
dev@243:     let lastPercentagePoint = 0;
dev@248:     return super.dispatch(method, request)
dev@243:       .scan(streamingResponseReducer)
dev@243:       .filter(val => {
dev@243:         const percentage =
dev@243:           100 * (val.processedBlockCount / val.totalBlockCount) | 0;
dev@243:         const pointDifference = (percentage - lastPercentagePoint);
dev@249:         const shouldEmit = pointDifference === 1 || percentage === 100;
dev@249:         if (shouldEmit) {
dev@243:           lastPercentagePoint = percentage;
dev@243:         }
dev@249:         return shouldEmit;
dev@243:       });
dev@243:   }
dev@243: }
dev@243: 
dev@40: export default class FeatureExtractionWorker {
dev@226:   private workerScope: DedicatedWorkerGlobalScope;
dev@72:   private remoteLibraries: Map<LibraryKey, LibraryUri>;
dev@226:   private server: WebWorkerStreamingServer;
dev@226:   private service: AggregateStreamingService;
dev@40: 
dev@226:   constructor(workerScope: DedicatedWorkerGlobalScope,
dev@226:               private requireJs: RequireJs) {
dev@40:     this.workerScope = workerScope;
dev@72:     this.remoteLibraries = new Map<LibraryKey, LibraryUri>();
dev@250:     this.service = new ThrottledReducingAggregateService();
dev@226:     this.setupImportLibraryListener();
dev@226:     this.server = new WebWorkerStreamingServer(
dev@226:       this.workerScope,
dev@226:       this.service
dev@72:     );
dev@226:   }
dev@72: 
dev@226:   private setupImportLibraryListener(): void {
dev@229: 
dev@44:     this.workerScope.onmessage = (ev: MessageEvent) => {
dev@64:       const sendResponse = (result) => {
dev@64:         this.workerScope.postMessage({
dev@64:           method: ev.data.method,
dev@64:           result: result
dev@64:         });
dev@64:       };
dev@44:       switch (ev.data.method) {
dev@72:         case 'import':
dev@72:           const key: LibraryKey = ev.data.params;
dev@72:           if (this.remoteLibraries.has(key)) {
dev@72:             this.requireJs([this.remoteLibraries.get(key)], (plugin) => {
dev@229:               // TODO a factory with more logic probably belongs in piper-js
dev@229:               const lib: any | EmscriptenModule = plugin.createLibrary();
dev@229:               const isEmscriptenModule = typeof lib.cwrap === 'function';
dev@229:               const service = new PiperStreamingService(
dev@229:                 isEmscriptenModule ? new PiperVampService(lib) : lib // TODO
dev@229:               );
dev@229:               this.service.addService(key, service);
dev@226:               this.service.list({}).then(sendResponse);
dev@72:             });
dev@72:           } else {
dev@72:             console.error('Non registered library key.'); // TODO handle error
dev@72:           }
dev@72:           break;
dev@72:         case 'addRemoteLibraries': // TODO rename
dev@72:           const available: AvailableLibraries = ev.data.params;
dev@236:           Object.keys(available).forEach(libraryKey => {
dev@236:             this.remoteLibraries.set(libraryKey, available[libraryKey]);
dev@72:           });
dev@44:       }
dev@44:     };
dev@40:   }
dev@40: }