001/*
002 * JDrupes Builder
003 * Copyright (C) 2025 Michael N. Lipp
004 * 
005 * This program is free software: you can redistribute it and/or modify
006 * it under the terms of the GNU Affero General Public License as
007 * published by the Free Software Foundation, either version 3 of the
008 * License, or (at your option) any later version.
009 *
010 * This program is distributed in the hope that it will be useful,
011 * but WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
013 * GNU Affero General Public License for more details.
014 *
015 * You should have received a copy of the GNU Affero General Public License
016 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
017 */
018
019package org.jdrupes.builder.core;
020
021import java.util.stream.Stream;
022import org.jdrupes.builder.api.Project;
023import org.jdrupes.builder.api.Resource;
024import org.jdrupes.builder.api.ResourceRequest;
025import org.jdrupes.builder.api.ResourceType;
026import org.jdrupes.builder.api.Resources;
027
028/// A provider of resources to be included in a project. This
029/// implementation can be used for all kinds of resources. Usually
030/// language specific packages derive specializations that bind
031/// this class to a specific type of resource. These specializations
032/// often also offer methods that ease the specification of resources
033/// to be included.
034///
035/// @param <T> the resource type
036///
037public class ResourceCollector<T extends Resource> extends AbstractGenerator {
038
039    private final ResourceType<T> type;
040    private final Resources<T> resources;
041
042    /// Instantiates a new resources collector.
043    ///
044    /// @param project the project
045    /// @param type the type of resources to collect
046    ///
047    public ResourceCollector(Project project, ResourceType<T> type) {
048        super(project);
049        this.type = type;
050        resources = Resources.with(type);
051    }
052
053    /// Adds the given file tree with resource directories.
054    ///
055    /// @param resources the resources
056    /// @return the resources collector
057    ///
058    public final ResourceCollector<T> add(T resources) {
059        this.resources.add(resources);
060        return this;
061    }
062
063    /// Adds the given file trees with resource directories.
064    ///
065    /// @param resources the resources
066    /// @return the resources collector
067    ///
068    public final ResourceCollector<T> add(Stream<T> resources) {
069        this.resources.addAll(resources);
070        return this;
071    }
072
073    /// Return the resources to collect.
074    ///
075    /// @return the resources
076    ///
077    public final Resources<T> resources() {
078        return resources;
079    }
080
081    @Override
082    @SuppressWarnings("unchecked")
083    protected <R extends Resource> Stream<R>
084            doProvide(ResourceRequest<R> requested) {
085        if (!requested.accepts(type)) {
086            return Stream.empty();
087        }
088        return (Stream<R>) resources.stream();
089    }
090
091}