package org.eclipse.aether.util.graph.transformer;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

import java.util.Collection;
import java.util.HashSet;
import java.util.Set;

import org.eclipse.aether.RepositoryException;
import org.eclipse.aether.util.artifact.JavaScopes;
import org.eclipse.aether.util.graph.transformer.ConflictResolver.ConflictContext;
import org.eclipse.aether.util.graph.transformer.ConflictResolver.ConflictItem;
import org.eclipse.aether.util.graph.transformer.ConflictResolver.ScopeSelector;

A scope selector for use with ConflictResolver that supports the scopes from JavaScopes. In general, this selector picks the widest scope present among conflicting dependencies where e.g. "compile" is wider than "runtime" which is wider than "test". If however a direct dependency is involved, its scope is selected. /**
 * A scope selector for use with {@link ConflictResolver} that supports the scopes from {@link JavaScopes}. In general,
 * this selector picks the widest scope present among conflicting dependencies where e.g. "compile" is wider than
 * "runtime" which is wider than "test". If however a direct dependency is involved, its scope is selected.
 */
public final class JavaScopeSelector
    extends ScopeSelector
{

    
Creates a new instance of this scope selector.
/**
     * Creates a new instance of this scope selector.
     */
    public JavaScopeSelector()
    {
    }

    @Override
    public void selectScope( ConflictContext context )
        throws RepositoryException
    {
        String scope = context.getWinner().getDependency().getScope();
        if ( !JavaScopes.SYSTEM.equals( scope ) )
        {
            scope = chooseEffectiveScope( context.getItems() );
        }
        context.setScope( scope );
    }

    private String chooseEffectiveScope( Collection<ConflictItem> items )
    {
        Set<String> scopes = new HashSet<>();
        for ( ConflictItem item : items )
        {
            if ( item.getDepth() <= 1 )
            {
                return item.getDependency().getScope();
            }
            scopes.addAll( item.getScopes() );
        }
        return chooseEffectiveScope( scopes );
    }

    private String chooseEffectiveScope( Set<String> scopes )
    {
        if ( scopes.size() > 1 )
        {
            scopes.remove( JavaScopes.SYSTEM );
        }

        String effectiveScope = "";

        if ( scopes.size() == 1 )
        {
            effectiveScope = scopes.iterator().next();
        }
        else if ( scopes.contains( JavaScopes.COMPILE ) )
        {
            effectiveScope = JavaScopes.COMPILE;
        }
        else if ( scopes.contains( JavaScopes.RUNTIME ) )
        {
            effectiveScope = JavaScopes.RUNTIME;
        }
        else if ( scopes.contains( JavaScopes.PROVIDED ) )
        {
            effectiveScope = JavaScopes.PROVIDED;
        }
        else if ( scopes.contains( JavaScopes.TEST ) )
        {
            effectiveScope = JavaScopes.TEST;
        }

        return effectiveScope;
    }

}