#region -[ Readme fuzzelogic Solutions: CrunchedSpecification]

/***
	Created by Zak for 
	Fuzzelogic Solutions
	www.fuzzelogicSolutions.com
	info@fuzzelogicSolutions.com
*/

#endregion

using System;

namespace FuzzelogicSolutions.Samples{
    public interface Ispecification<T>
    {
        bool is_satisfied_by(T this_item);
    }

    public class specification<T> : Ispecification<T>{
        private readonly Predicate<T> specification_predicate_test;

        public specification(Predicate<T> specification_predicate_test){
            this.specification_predicate_test = specification_predicate_test;
        }

        public bool is_satisfied_by(T this_item){
            return specification_predicate_test(this_item);
        }
    }

    // put this into a seperate class
    public static class specification_extensions{
        public static specification<T> And<T>(this specification<T> first, Predicate<T> secondPredicate)
        {
            return new specification<T>(instance => first.is_satisfied_by(instance) && new specification<T>(secondPredicate).is_satisfied_by(instance));
        }
        public static specification<T> OR<T>(this specification<T> first, Predicate<T> secondPredicate)
        {
            return new specification<T>(instance => first.is_satisfied_by(instance) || new specification<T>(secondPredicate).is_satisfied_by(instance));
        }
        public static specification<T> Negate<T>(this specification<T> first)
        {
            return new specification<T>(instance => !first.is_satisfied_by(instance));
        }
    }
}