/*
 * Copyright 2015 the original author or authors.
 *
 * 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 org.gradle.api.internal.artifacts.ivyservice.resolveengine.artifact;

import org.gradle.api.artifacts.ResolutionStrategy;
import org.gradle.api.artifacts.component.BuildIdentifier;
import org.gradle.api.artifacts.component.ComponentIdentifier;
import org.gradle.api.artifacts.component.ProjectComponentIdentifier;
import org.gradle.api.internal.artifacts.ivyservice.resolveengine.graph.DependencyGraphNode;
import org.gradle.internal.component.local.model.LocalConfigurationMetadata;
import org.gradle.internal.component.local.model.LocalFileDependencyMetadata;
import org.gradle.internal.component.model.ConfigurationMetadata;

import java.util.ArrayList;
import java.util.List;

/**
 * Collects all artifacts and their build dependencies.
 */
public class DefaultResolvedArtifactsBuilder implements DependencyArtifactsVisitor {
    private final boolean buildProjectDependencies;
    private final ResolutionStrategy.SortOrder sortOrder;
    private final List<ArtifactSet> artifactSetsById = new ArrayList<ArtifactSet>();
    private final BuildIdentifier thisBuild;

    public DefaultResolvedArtifactsBuilder(BuildIdentifier thisBuild, boolean buildProjectDependencies, ResolutionStrategy.SortOrder sortOrder) {
        this.thisBuild = thisBuild;
        this.buildProjectDependencies = buildProjectDependencies;
        this.sortOrder = sortOrder;
    }

    @Override
    public void startArtifacts(DependencyGraphNode root) {
    }

    @Override
    public void visitNode(DependencyGraphNode node) {
    }

    @Override
    public void visitArtifacts(DependencyGraphNode from, LocalFileDependencyMetadata fileDependency, int artifactSetId, ArtifactSet artifacts) {
        collectArtifacts(artifactSetId, artifacts);
    }

    @Override
    public void visitArtifacts(DependencyGraphNode from, DependencyGraphNode to, int artifactSetId, ArtifactSet artifacts) {
        // Don't collect build dependencies if not required
        if (!buildProjectDependencies) {
            artifacts = new NoBuildDependenciesArtifactSet(artifacts);
        } else {
            ConfigurationMetadata configurationMetadata = to.getMetadata();
            if (configurationMetadata instanceof LocalConfigurationMetadata) {
                // For a dependency from _another_ build to _this_ build, don't make the artifact buildable
                // Making these artifacts buildable leads to poor error reporting due to direct task dependency cycle (losing the intervening build dependencies)
                ComponentIdentifier incomingId = from.getOwner().getComponentId();
                ComponentIdentifier outgoingId = to.getOwner().getComponentId();
                if (incomingId instanceof ProjectComponentIdentifier && outgoingId instanceof ProjectComponentIdentifier) {
                    if (!isCurrentBuild(incomingId) && isCurrentBuild(outgoingId)) {
                        artifacts = new NoBuildDependenciesArtifactSet(artifacts);
                    }
                }
            }
        }
        collectArtifacts(artifactSetId, artifacts);
    }

    private boolean isCurrentBuild(ComponentIdentifier incomingId) {
        return ((ProjectComponentIdentifier) incomingId).getBuild().equals(thisBuild);
    }

    private void collectArtifacts(int artifactSetId, ArtifactSet artifacts) {
        // Collect artifact sets in a list, using the id of the set as its index in the list
        assert artifactSetsById.size() >= artifactSetId;
        if (artifactSetsById.size() == artifactSetId) {
            artifactSetsById.add(artifacts);
        }
    }

    @Override
    public void finishArtifacts() {
    }

    public VisitedArtifactsResults complete() {
        return new DefaultVisitedArtifactResults(sortOrder, artifactSetsById);
    }
}
