AccessoryController.java

package com.beowulfe.hap.impl.json;

import java.io.ByteArrayOutputStream;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.concurrent.CompletableFuture;

import javax.json.Json;
import javax.json.JsonArrayBuilder;
import javax.json.JsonObject;
import javax.json.JsonObjectBuilder;

import com.beowulfe.hap.HomekitAccessory;
import com.beowulfe.hap.Service;
import com.beowulfe.hap.characteristics.Characteristic;
import com.beowulfe.hap.impl.HomekitRegistry;
import com.beowulfe.hap.impl.http.HttpResponse;

public class AccessoryController {

	private final HomekitRegistry registry;
	
	public AccessoryController(HomekitRegistry registry) {
		this.registry = registry;
	}

	public HttpResponse listing() throws Exception {
		JsonArrayBuilder accessories = Json.createArrayBuilder();
		
		Map<Integer, List<CompletableFuture<JsonObject>>> accessoryServiceFutures = new HashMap<>();
		for (HomekitAccessory accessory: registry.getAccessories()) {
			int iid = 0;
			List<CompletableFuture<JsonObject>> serviceFutures = new ArrayList<>();
			for (Service service: registry.getServices(accessory.getId())) {
				serviceFutures.add(toJson(service, iid));
				iid += service.getCharacteristics().size() + 1;
			}
			accessoryServiceFutures.put(accessory.getId(), serviceFutures);
		}
		
		Map<Integer, JsonArrayBuilder> serviceArrayBuilders = new HashMap<>();
		for (Entry<Integer, List<CompletableFuture<JsonObject>>> entry: accessoryServiceFutures.entrySet()) {
			JsonArrayBuilder arr = Json.createArrayBuilder();
			for (CompletableFuture<JsonObject> future: entry.getValue()) {
				arr.add(future.join());
			}
			serviceArrayBuilders.put(entry.getKey(), arr);
		}
		
		for (HomekitAccessory accessory: registry.getAccessories()) {
			accessories.add(Json.createObjectBuilder().add("aid", accessory.getId()).add("services", serviceArrayBuilders.get(accessory.getId())));
		}
						
		try(ByteArrayOutputStream baos = new ByteArrayOutputStream()) {
			Json.createWriter(baos).write(
				Json.createObjectBuilder().add("accessories", accessories).build()
			);
			return new HapJsonResponse(baos.toByteArray());
		}
	}
	
	private CompletableFuture<JsonObject> toJson(Service service, int interfaceId) throws Exception {
		JsonObjectBuilder builder = Json.createObjectBuilder()
			.add("iid", ++interfaceId)
			.add("type", service.getType());
		List<Characteristic> characteristics = service.getCharacteristics();
		Collection<CompletableFuture<JsonObject>> characteristicFutures = new ArrayList<>(characteristics.size());
		for (Characteristic characteristic: characteristics) {
			characteristicFutures.add(characteristic.toJson(++interfaceId));
		}
		
		return CompletableFuture.allOf(characteristicFutures.toArray(new CompletableFuture<?>[characteristicFutures.size()]))
			.thenApply(v -> {
				JsonArrayBuilder jsonCharacteristics = Json.createArrayBuilder();
				characteristicFutures.stream().map(future -> future.join()).forEach(c -> jsonCharacteristics.add(c));
				builder.add("characteristics", jsonCharacteristics);
				return builder.build();
			});
	}
}