import { GeoJson , ITiler , WorkerServiceProtocol , WorkerTilerProtocol } from "@here/harp-datasource-protocol" ; import { TileKey } from "@here/harp-geoutils" ; import { ConcurrentWorkerSet } from "./ConcurrentWorkerSet" ; /**
 * Identifier of next tiler worker-service. Used to ensure uniqueness of service ids of tilers
 * dedicated to different datasources.
 */ let nextUniqueServiceId = 0 ; /**
 * Tiler based on [[ConcurrentWorkerSet]].
 *
 * Tiles payloads using workers running in separate contexts (also known as `WebWorkers`):
 * - connection establishment,
 * - sends tile requests,
 * - configuration.
 */ export class WorkerBasedTiler implements ITiler { private readonly serviceId : string ; private m_serviceCreated : boolean = false ; param workerSet param tilerServiceType constructor ( private readonly workerSet , private readonly tilerServiceType ) { this . workerSet . addReference ( ) ; this . serviceId = `${ this . tilerServiceType }-${ nextUniqueServiceId ++ }` ; } /**
     * Dispose of dedicated tiler services in workers and remove reference to underlying
     * [[ConcurrentWorkerSet]].
     */ dispose ( ) { if ( this . m_serviceCreated ) { this . workerSet . broadcastRequest ( WorkerServiceProtocol . WORKER_SERVICE_MANAGER_SERVICE_ID , { type : WorkerServiceProtocol . Requests . DestroyService , targetServiceId : this . serviceId } ) . catch ( ( ) => { } ) ; } this . workerSet . removeReference ( ) ; } /**
     * Connects to [[WorkerServiceManager]]s in underlying [[ConcurrentWorkerSet]] and creates
     * dedicated [[TilerService]]s in all workers to serve tiling requests.
     */ async connect ( ) { await this . workerSet . connect ( WorkerServiceProtocol . WORKER_SERVICE_MANAGER_SERVICE_ID ) ; if ( ! this . m_serviceCreated ) { await this . workerSet . broadcastRequest ( WorkerServiceProtocol . WORKER_SERVICE_MANAGER_SERVICE_ID , { type : WorkerServiceProtocol . Requests . CreateService , targetServiceType : this . tilerServiceType , targetServiceId : this . serviceId } ) ; this . m_serviceCreated = true ; } } param indexId param input registerIndex ( indexId , input ) { const message = { type : WorkerTilerProtocol . Requests . RegisterIndex , id : indexId , input : input instanceof URL ? input . href : ( input as GeoJson ) } ; return this . workerSet . invokeRequest ( this . serviceId , message ) ; } param indexId param input updateIndex ( indexId , input ) { const message = { type : WorkerTilerProtocol . Requests . UpdateIndex , id : indexId , input : input instanceof URL ? input . href : ( input as GeoJson ) } ; return this . workerSet . invokeRequest ( this . serviceId , message ) ; } param indexId param tileKey - The  {@link @here/harp-geoutils#TileKey} that identifies the tile.
      getTile ( indexId , tileKey ) { const tileKeyCode = tileKey . mortonCode ( ) ; const message = { type : WorkerTilerProtocol . Requests . TileRequest , index : indexId , tileKey : tileKeyCode } ; return this . workerSet . invokeRequest ( this . serviceId , message ) ; } }