/*
 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
 *
 * 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.drools.examples.fibonacci

import org.drools.examples.fibonacci.FibonacciExample.Fibonacci;

dialect "mvel"

rule Recurse
    salience 10
    when
        f : Fibonacci ( value == -1 )
        not ( Fibonacci ( sequence == 1 ) )    
    then
        insert( new Fibonacci( f.sequence - 1 ) );
        System.out.println( "recurse for " + f.sequence );
end

rule Bootstrap
    when
        f : Fibonacci( sequence == 1 || == 2, value == -1 ) // this is a multi-restriction || on a single field
    then 
        modify ( f ){ value = 1 };
        System.out.println( f.sequence + " == " + f.value );
end

rule Calculate
    when
        f1 : Fibonacci( s1 : sequence, value != -1 ) // here we bind sequence
        f2 : Fibonacci( sequence == (s1 + 1 ), value != -1 ) // here we don't, just to demonstrate the different way bindings can be used
        f3 : Fibonacci( s3 : sequence == (f2.sequence + 1 ), value == -1 )              
    then    
        modify ( f3 ) { value = f1.value + f2.value };
        System.out.println( s3 + " == " + f3.value ); // see how you can access pattern and field  bindings
end 
