BooleanExpression.java

/*
 *  Copyright (c) 2014, Lukas Tenbrink.
 *  * http://lukas.axxim.net
 */

package ivorius.reccomplex.utils;

import com.google.common.base.Function;
import com.google.common.base.Predicate;

/**
 * Created by lukas on 23.02.15.
 */
public abstract class BooleanExpression
{
    public static Predicate<Predicate<String>> parse(String string)
    {
        int index = 0;

        while (index < string.length())
        {
            break;
        }

        return null;
    }

    public static <T> Predicate<Predicate<T>> mapExpression(final Predicate<Predicate<String>> expression, final Function<String, T> mapping)
    {
        return new Predicate<Predicate<T>>()
        {
            @Override
            public boolean apply(final Predicate<T> tPredicate)
            {
                return expression.apply(new Predicate<String>()
                {
                    @Override
                    public boolean apply(String input)
                    {
                        return tPredicate.apply(mapping.apply(input));
                    }
                });
            }
        };
    }

    public abstract static class Unary implements Predicate<Predicate<String>>
    {
        public Predicate<Predicate<String>> expression;

        public Unary(Predicate<Predicate<String>> expression)
        {
            this.expression = expression;
        }
    }

    public abstract static class Binary implements Predicate<Predicate<String>>
    {
        public Predicate<Predicate<String>> left;
        public Predicate<Predicate<String>> right;

        public Binary(Predicate<Predicate<String>> left, Predicate<Predicate<String>> right)
        {
            this.left = left;
            this.right = right;
        }
    }

    public static class Variable implements Predicate<Predicate<String>>
    {
        public String variable;

        public Variable(String variable)
        {
            this.variable = variable;
        }

        @Override
        public boolean apply(Predicate<String> input)
        {
            return input != null && input.apply(variable);
        }
    }

    public static class Not extends Unary
    {
        public Not(Predicate<Predicate<String>> expression)
        {
            super(expression);
        }

        @Override
        public boolean apply(Predicate<String> input)
        {
            return !expression.apply(input);
        }
    }

    public static class And extends Binary
    {
        public And(Predicate<Predicate<String>> left, Predicate<Predicate<String>> right)
        {
            super(left, right);
        }

        @Override
        public boolean apply(Predicate<String> input)
        {
            return left.apply(input) && right.apply(input);
        }
    }

    public static class Or extends Binary
    {
        public Or(Predicate<Predicate<String>> left, Predicate<Predicate<String>> right)
        {
            super(left, right);
        }

        @Override
        public boolean apply(Predicate<String> input)
        {
            return left.apply(input) || right.apply(input);
        }
    }
}