/*
 * Adapted from The MIT License (MIT)
 *
 * Copyright (c) 2018-2024 DaPorkchop_
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy,
 * modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software
 * is furnished to do so, subject to the following conditions:
 *
 * Any persons and/or organizations using this software must include the above copyright notice and this permission notice,
 * provide sufficient credit to the original authors of the project (IE: DaPorkchop_), as well as provide a link to the original project.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

package net.daporkchop.lib.common.stream;

import lombok.AllArgsConstructor;
import lombok.NonNull;
import lombok.experimental.UtilityClass;

import java.util.Iterator;
import java.util.Spliterator;
import java.util.function.Consumer;
import java.util.stream.Stream;

/**
 * Helper methods for working with the {@link java.util.stream.Stream Stream} API.
 *
 * @author DaPorkchop_
 */
@UtilityClass
public class PStreams {
    /**
     * Gets an {@link Iterable} over the given {@link Stream}.
     * <p>
     * Due to the nature of the stream API, the returned {@link Iterable} may only be used once.
     *
     * @param stream the {@link Stream} to iterate over
     * @return an {@link Iterable}
     */
    public static <T> Iterable<T> toIterable(@NonNull Stream<T> stream) {
        return new StreamAsIterable<>(stream);
    }

    /**
     * @author DaPorkchop_
     */
    @AllArgsConstructor
    private static final class StreamAsIterable<T> implements Iterable<T> {
        private Stream<T> stream;

        private Stream<T> stream() {
            Stream<T> stream = this.stream;
            this.stream = null;

            if (stream == null) {
                throw new IllegalStateException("A stream-backed iterable may only be used once!");
            }
            return stream;
        }

        @Override
        public Iterator<T> iterator() {
            return this.stream().iterator();
        }

        @Override
        public void forEach(Consumer<? super T> action) {
            this.stream().forEach(action);
        }

        @Override
        public Spliterator<T> spliterator() {
            return this.stream().spliterator();
        }
    }
}
