content: /*
   * Copyright (C) 2020 ActiveJ LLC.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package io.activej.async.callback;
  
  import io.activej.common.function.RunnableEx;
  import io.activej.common.function.SupplierEx;
  
  import static io.activej.common.exception.FatalErrorHandler.handleError;
  
  public interface AsyncComputation<T> {
  	void call(Callback<? super T> cb);
  
  	static AsyncComputation<Void> of(RunnableEx runnable) {
  		return cb -> {
  			try {
  				runnable.run();
  			} catch (Exception ex) {
  				handleError(ex, runnable);
  				cb.accept(null, ex);
  				return;
  			}
  			cb.accept(null, null);
  		};
  	}
  
  	static <T> AsyncComputation<T> of(SupplierEx<? extends T> runnable) {
  		return cb -> {
  			T result;
  			try {
  				result = runnable.get();
  			} catch (Exception ex) {
  				handleError(ex, runnable);
  				cb.accept(null, ex);
  				return;
  			}
  			cb.accept(result, null);
  		};
  	}
  
  	static <T> AsyncComputation<T> ofSupplier(SupplierEx<? extends AsyncComputation<? extends T>> computationSupplier) {
  		return cb -> {
  			AsyncComputation<? extends T> computation;
  			try {
  				computation = computationSupplier.get();
  			} catch (Exception ex) {
  				handleError(ex, computationSupplier);
  				cb.accept(null, ex);
  				return;
  			}
  			computation.call(cb);
  		};
  	}
  }
  