package org.simantics.scl.runtime.tests;

import java.util.Random;

import org.junit.Assert;
import org.junit.Test;
import org.simantics.scl.runtime.chr.Fact;
import org.simantics.scl.runtime.chr.FactActivationQueue;

import gnu.trove.list.array.TIntArrayList;

public class TestFactActivationQueue {
    public static Random RANDOM = new Random();
    
    private static class MyFact implements Fact {
        TIntArrayList list;
        int priority;

        public MyFact(TIntArrayList list, int priority) {
            this.list = list;
            this.priority = priority;
        }

        @Override
        public int activate(Object context, int priority) {
            Assert.assertEquals(this.priority, priority);
            list.add(priority);
            return -1;
        }

        @Override
        public boolean isAlive() {
            return true;
        }
    }
    
    private void testRandomly(int priorities, int size) {
        FactActivationQueue queue = new FactActivationQueue(priorities);
        TIntArrayList list = new TIntArrayList(size); 
        for(int i=0;i<size;++i) {
            int val = RANDOM.nextInt(priorities);
            queue.add(val, new MyFact(list, val));
        }
        queue.activate(null, priorities);
        Assert.assertEquals(size, list.size());
        for(int i=1;i<list.size();++i) {
            int a = list.get(i-1);
            int b = list.get(i);
            Assert.assertTrue(a <= b);
        }
    }
    
    @Test
    public void testRandomly() {
        for(int i=0;i<10000;++i)
            testRandomly(10, 10000);
    }
}