CExists.java

/*
 * @cond LICENSE
 * ######################################################################################
 * # LGPL License                                                                       #
 * #                                                                                    #
 * # This file is part of the LightJason AgentSpeak(L++)                                #
 * # Copyright (c) 2015-19, LightJason (info@lightjason.org)                            #
 * # This program is free software: you can redistribute it and/or modify               #
 * # it under the terms of the GNU Lesser General Public License as                     #
 * # published by the Free Software Foundation, either version 3 of the                 #
 * # License, or (at your option) any later version.                                    #
 * #                                                                                    #
 * # This program is distributed in the hope that it will be useful,                    #
 * # but WITHOUT ANY WARRANTY; without even the implied warranty of                     #
 * # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the                      #
 * # GNU Lesser General Public License for more details.                                #
 * #                                                                                    #
 * # You should have received a copy of the GNU Lesser General Public License           #
 * # along with this program. If not, see http://www.gnu.org/licenses/                  #
 * ######################################################################################
 * @endcond
 */

package org.lightjason.agentspeak.action.builtin.storage;

import org.lightjason.agentspeak.language.CCommon;
import org.lightjason.agentspeak.language.CRawTerm;
import org.lightjason.agentspeak.language.ITerm;
import org.lightjason.agentspeak.language.execution.IContext;
import org.lightjason.agentspeak.language.fuzzy.CFuzzyValue;
import org.lightjason.agentspeak.language.fuzzy.IFuzzyValue;

import javax.annotation.Nonnegative;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import java.util.List;
import java.util.function.Function;
import java.util.stream.Stream;


/**
 * check if an element exists within the agent-storage.
 * The action checks if an element is within the action and
 * returns the boolean flag, the action never fails
 *
 * {@code [A|B] = storage/exist( "foo", "bar" );}
 */
public final class CExists extends IStorage
{
    /**
     * serial id
     */
    private static final long serialVersionUID = 8505190439682767260L;

    /**
     * ctor
     */
    public CExists()
    {
        super();
    }

    /**
     * ctor
     *
     * @param p_resolver resolver function
     */
    public CExists( @Nonnull final Function<String, Boolean> p_resolver )
    {
        super( p_resolver );
    }

    /**
     * ctor
     *
     * @param p_forbidden forbidden keys
     */
    public CExists( @Nullable final String... p_forbidden )
    {
        super( p_forbidden );
    }

    /**
     * ctor
     *
     * @param p_fordbidden stream with borbidden keys
     */
    public CExists( @Nonnull final Stream<String> p_fordbidden )
    {
        super( p_fordbidden );
    }

    @Nonnegative
    @Override
    public final int minimalArgumentNumber()
    {
        return 1;
    }

    @Nonnull
    @Override
    public final IFuzzyValue<Boolean> execute( final boolean p_parallel, @Nonnull final IContext p_context,
                                               @Nonnull final List<ITerm> p_argument, @Nonnull final List<ITerm> p_return
    )
    {
        CCommon.flatten( p_argument )
               .map( ITerm::<String>raw )
               .map( i -> ( !m_resolver.apply( i ) ) && ( p_context.agent().storage().containsKey( i ) ) )
               .map( CRawTerm::from )
               .forEach( p_return::add );

        return CFuzzyValue.from( true );
    }

}