package com.sample;

import java.io.InputStreamReader;
import java.io.Reader;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

import org.drools.RuleBase;
import org.drools.RuleBaseFactory;
import org.drools.WorkingMemory;
import org.drools.compiler.PackageBuilder;
import org.drools.rule.Package;

/**
 * This is a sample file to launch a rule package from a rule source file.
 */
public class DroolsTest {

    public static final void main(String[] args) {
        try {
        	
        	//load up the rulebase
            RuleBase ruleBase = readRule();
            WorkingMemory workingMemory = ruleBase.newStatefulSession();
            
            //go !
            Satellite satellite = new Satellite("foo");
            satellite.setOverhead(true);
            workingMemory.insert( satellite );
            workingMemory.insert( new Satellite("bar") );
            workingMemory.insert( new SatelliteManager("bas") );
            
            workingMemory.fireAllRules();   
            
            
        } catch (Throwable t) {
            t.printStackTrace();
        }
    }

    /**
     * Please note that this is the "low level" rule assembly API.
     */
	private static RuleBase readRule() throws Exception {
		//read in the source
		Reader source = new InputStreamReader( DroolsTest.class.getResourceAsStream( "/Sample.drl" ) );
		
		//optionally read in the DSL (if you are using it).
		//Reader dsl = new InputStreamReader( DroolsTest.class.getResourceAsStream( "/mylang.dsl" ) );

		//Use package builder to build up a rule package.
		//An alternative lower level class called "DrlParser" can also be used...
		
		PackageBuilder builder = new PackageBuilder();

		//this will parse and compile in one step
		//NOTE: There are 2 methods here, the one argument one is for normal DRL.
		builder.addPackageFromDrl( source );

		//Use the following instead of above if you are using a DSL:
		//builder.addPackageFromDrl( source, dsl );
		
		//get the compiled package (which is serializable)
		Package pkg = builder.getPackage();
		
		//add the package to a rulebase (deploy the rule package).
		RuleBase ruleBase = RuleBaseFactory.newRuleBase();
		ruleBase.addPackage( pkg );
		return ruleBase;
	}
	
	public static class Satellite {
		
		private final String name;
		private boolean overhead = false;
		
		public Satellite(String name) {
			this.name = name;
		}
		
		public boolean isOverhead() {
			return this.overhead;
		}
		
		public void setOverhead(boolean overhead) {
			this.overhead = overhead;
		}
		
		public String toString()
		{
			return "Satellite " + name;
		}

		@Override
		public int hashCode() {
			final int prime = 31;
			int result = 1;
			result = prime * result + ((name == null) ? 0 : name.hashCode());
			result = prime * result + (overhead ? 1231 : 1237);
			return result;
		}

		@Override
		public boolean equals(Object obj) {
			if (this == obj)
				return true;
			if (obj == null)
				return false;
			if (getClass() != obj.getClass())
				return false;
			Satellite other = (Satellite) obj;
			if (name == null) {
				if (other.name != null)
					return false;
			} else if (!name.equals(other.name))
				return false;
			if (overhead != other.overhead)
				return false;
			return true;
		}
	}
	
	public static class SatelliteManager implements Iterable<Satellite> {

		private final String name;
		private Collection<Satellite> satellites = new ArrayList<Satellite>();
		
		public SatelliteManager(String name) {
			this.name = name;
		}

		public void setSatellites(Collection<Satellite> satellites) {
			this.satellites = satellites;
		}

		public Collection<Satellite> getSatellites() {
			return satellites;
		}

		public Iterator<Satellite> iterator() {
			return satellites.iterator();
		}
		
		public String toString()
		{
			return "SatelliteManager " + name;
		}

		@Override
		public int hashCode() {
			final int prime = 31;
			int result = 1;
			result = prime * result + ((name == null) ? 0 : name.hashCode());
			result = prime * result
					+ ((satellites == null) ? 0 : satellites.hashCode());
			return result;
		}

		@Override
		public boolean equals(Object obj) {
			if (this == obj)
				return true;
			if (obj == null)
				return false;
			if (getClass() != obj.getClass())
				return false;
			SatelliteManager other = (SatelliteManager) obj;
			if (name == null) {
				if (other.name != null)
					return false;
			} else if (!name.equals(other.name))
				return false;
			if (satellites == null) {
				if (other.satellites != null)
					return false;
			} else if (!satellites.equals(other.satellites))
				return false;
			return true;
		}
	}
    
}