/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.pig.test;

/*
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.PipedInputStream;
import java.io.PipedOutputStream;
import java.util.Iterator;
import java.util.Random;
*/

import java.util.*;
import java.io.IOException;

import org.junit.Test;

import org.apache.pig.data.*;
import org.apache.pig.impl.eval.*;
import org.apache.pig.impl.util.Spillable;

/**
 * This class will exercise the basic Pig data model and members. It tests for proper behavior in
 * assigment and comparision, as well as function application.
 * 
 * @author dnm
 */
public class TestDataBag extends junit.framework.TestCase {

    private Random rand = new Random();

    private class TestMemoryManager {
        ArrayList<Spillable> mManagedObjects = new ArrayList<Spillable>();

        public void register(Spillable s) {
            mManagedObjects.add(s);
        }

        public void forceSpill() throws IOException {
            Iterator<Spillable> i = mManagedObjects.iterator();
            while (i.hasNext()) i.next().spill();
        }
    }

    // Need to override the regular bag factory so I can register with my local
    // memory manager.
    private class LocalBagFactory {
        TestMemoryManager mMemMgr;

        public LocalBagFactory(TestMemoryManager mgr) {
            mMemMgr = mgr;
        }

        public DataBag newDefaultBag() {
            DataBag bag = new DefaultDataBag();
            mMemMgr.register(bag);
            return bag;
        }

        public DataBag newSortedBag(EvalSpec sortSpec) {
            DataBag bag = new SortedDataBag(sortSpec);
            mMemMgr.register(bag);
            return bag;
        }

        public DataBag newDistinctBag() {
            DataBag bag = new DistinctDataBag();
            mMemMgr.register(bag);
            return bag;
        }
    }

    // Test reading and writing default from memory, no spills.
    @Test
    public void testDefaultInMemory() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDefaultBag();
        ArrayList<Tuple> rightAnswer = new ArrayList<Tuple>(10);

        // Write tuples into both
        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(i));
            b.add(t);
            rightAnswer.add(t);
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

   // Test reading and writing default from file with one spill
    @Test
    public void testDefaultSingleSpill() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDefaultBag();
        ArrayList<Tuple> rightAnswer = new ArrayList<Tuple>(10);

        // Write tuples into both
        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(i));
            b.add(t);
            rightAnswer.add(t);
        }
        mgr.forceSpill();

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

   // Test reading and writing default from file with three spills
    @Test
    public void testDefaultTripleSpill() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDefaultBag();
        ArrayList<Tuple> rightAnswer = new ArrayList<Tuple>(30);

        // Write tuples into both
        for (int j = 0; j < 3; j++) {
            for (int i = 0; i < 10; i++) {
                Tuple t = new Tuple(new DataAtom(i));
                b.add(t);
                rightAnswer.add(t);
            }
            mgr.forceSpill();
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

    // Test reading with some in file, some in memory.
    @Test
    public void testDefaultInMemInFile() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDefaultBag();
        ArrayList<Tuple> rightAnswer = new ArrayList<Tuple>(20);

        // Write tuples into both
        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(i));
            b.add(t);
            rightAnswer.add(t);
        }
        mgr.forceSpill();

        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(i));
            b.add(t);
            rightAnswer.add(t);
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

   // Test reading with a spill happening in the middle of the read.
    @Test
    public void testDefaultSpillDuringRead() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDefaultBag();
        ArrayList<Tuple> rightAnswer = new ArrayList<Tuple>(20);

        // Write tuples into both
        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(i));
            b.add(t);
            rightAnswer.add(t);
        }
        mgr.forceSpill();

        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(i));
            b.add(t);
            rightAnswer.add(t);
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        for (int i = 0; i < 15; i++) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        mgr.forceSpill();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

    // Test reading and writing sorted from memory, no spills.
    @Test
    public void testSortedInMemory() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newSortedBag(null);
        PriorityQueue<Tuple> rightAnswer = new PriorityQueue<Tuple>(10);

        // Write tuples into both
        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt()));
            b.add(t);
            rightAnswer.add(t);
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();

        Tuple t;
        while ((t = rightAnswer.poll()) != null) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), t);
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

   // Test reading and writing default from file with one spill
    @Test
    public void testSortedSingleSpill() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newSortedBag(null);
        PriorityQueue<Tuple> rightAnswer = new PriorityQueue<Tuple>(10);

        // Write tuples into both
        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt()));
            b.add(t);
            rightAnswer.add(t);
        }
        mgr.forceSpill();

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Tuple t;
        while ((t = rightAnswer.poll()) != null) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), t);
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

   // Test reading and writing default from file with three spills
    @Test
    public void testSortedTripleSpill() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newSortedBag(null);
        PriorityQueue<Tuple> rightAnswer = new PriorityQueue<Tuple>(30);

        // Write tuples into both
        for (int j = 0; j < 3; j++) {
            for (int i = 0; i < 10; i++) {
                Tuple t = new Tuple(new DataAtom(rand.nextInt()));
                b.add(t);
                rightAnswer.add(t);
            }
            mgr.forceSpill();
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();

        Tuple t;
        while ((t = rightAnswer.poll()) != null) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), t);
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

    // Test reading with some in file, some in memory.
    @Test
    public void testSortedInMemInFile() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newSortedBag(null);
        PriorityQueue<Tuple> rightAnswer = new PriorityQueue<Tuple>(20);

        // Write tuples into both
        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt()));
            b.add(t);
            rightAnswer.add(t);
        }
        mgr.forceSpill();

        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt()));
            b.add(t);
            rightAnswer.add(t);
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Tuple t;
        while ((t = rightAnswer.poll()) != null) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), t);
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

    // Test reading with a spill happening in the middle of the read.
    @Test
    public void testSortedSpillDuringRead() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newSortedBag(null);
        PriorityQueue<Tuple> rightAnswer = new PriorityQueue<Tuple>(20);

        // Write tuples into both
        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt()));
            b.add(t);
            rightAnswer.add(t);
        }
        mgr.forceSpill();

        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt()));
            b.add(t);
            rightAnswer.add(t);
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();

        for (int i = 0; i < 15; i++) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rightAnswer.poll());
        }

        mgr.forceSpill();

        Tuple t;
        while ((t = rightAnswer.poll()) != null) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), t);
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

    // Test reading with first spill happening in the middle of the read.
    @Test
    public void testSortedFirstSpillDuringRead() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newSortedBag(null);
        PriorityQueue<Tuple> rightAnswer = new PriorityQueue<Tuple>(20);

        for (int i = 0; i < 10; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt()));
            b.add(t);
            rightAnswer.add(t);
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();

        for (int i = 0; i < 5; i++) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rightAnswer.poll());
        }

        mgr.forceSpill();

        Tuple t;
        while ((t = rightAnswer.poll()) != null) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), t);
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

   // Test reading and writing sorted file with so many spills it requires
   // premerge.
    @Test
    public void testSortedPreMerge() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newSortedBag(null);
        PriorityQueue<Tuple> rightAnswer = new PriorityQueue<Tuple>(30);

        // Write tuples into both
        for (int j = 0; j < 373; j++) {
            for (int i = 0; i < 10; i++) {
                Tuple t = new Tuple(new DataAtom(rand.nextInt()));
                b.add(t);
                rightAnswer.add(t);
            }
            mgr.forceSpill();
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();

        Tuple t;
        while ((t = rightAnswer.poll()) != null) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), t);
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

    // Test reading and writing distinct from memory, no spills.
    @Test
    public void testDistinctInMemory() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDistinctBag();
        TreeSet<Tuple> rightAnswer = new TreeSet<Tuple>();

        // Write tuples into both
        for (int i = 0; i < 50; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt() % 5));
            b.add(t);
            rightAnswer.add(t);
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

   // Test reading and writing distinct from file with one spill
    @Test
    public void testDistinctSingleSpill() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDistinctBag();
        TreeSet<Tuple> rightAnswer = new TreeSet<Tuple>();

        // Write tuples into both
        for (int i = 0; i < 50; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt() % 5));
            b.add(t);
            rightAnswer.add(t);
        }
        mgr.forceSpill();

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

   // Test reading and writing distinct from file with three spills
    @Test
    public void testDistinctTripleSpill() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDistinctBag();
        TreeSet<Tuple> rightAnswer = new TreeSet<Tuple>();

        // Write tuples into both
        for (int j = 0; j < 3; j++) {
            for (int i = 0; i < 50; i++) {
                Tuple t = new Tuple(new DataAtom(rand.nextInt() % 5));
                b.add(t);
                rightAnswer.add(t);
            }
            mgr.forceSpill();
        }
        
        assertEquals("Size of distinct data bag is incorrect", b.size(), rightAnswer.size());

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

    // Test reading with some in file, some in memory.
    @Test
    public void testDistinctInMemInFile() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDistinctBag();
        TreeSet<Tuple> rightAnswer = new TreeSet<Tuple>();

        // Write tuples into both
        for (int i = 0; i < 50; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt() % 5));
            b.add(t);
            rightAnswer.add(t);
        }
        mgr.forceSpill();

        for (int i = 0; i < 50; i++) {
            Tuple t = new Tuple(new DataAtom(i));
            b.add(t);
            rightAnswer.add(t);
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

   // Test reading with a spill happening in the middle of the read.
    @Test
    public void testDistinctSpillDuringRead() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDistinctBag();
        TreeSet<Tuple> rightAnswer = new TreeSet<Tuple>();

        // Write tuples into both
        for (int i = 0; i < 50; i++) {
            Tuple t = new Tuple(new DataAtom(rand.nextInt() % 5));
            b.add(t);
            rightAnswer.add(t);
        }
        mgr.forceSpill();

        for (int i = 0; i < 50; i++) {
            Tuple t = new Tuple(new DataAtom(i));
            b.add(t);
            rightAnswer.add(t);
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        for (int i = 0; i < 5; i++) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        mgr.forceSpill();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

   // Test reading and writing distinct from file with enough spills to
   // force a pre-merge
    @Test
    public void testDistinctPreMerge() throws Exception {
        TestMemoryManager mgr = new TestMemoryManager();
        LocalBagFactory factory = new LocalBagFactory(mgr);
        DataBag b = factory.newDistinctBag();
        TreeSet<Tuple> rightAnswer = new TreeSet<Tuple>();

        // Write tuples into both
        for (int j = 0; j < 321; j++) {
            for (int i = 0; i < 50; i++) {
                Tuple t = new Tuple(new DataAtom(rand.nextInt() % 5));
                b.add(t);
                rightAnswer.add(t);
            }
            mgr.forceSpill();
        }

        // Read tuples back, hopefully they come out in the same order.
        Iterator<Tuple> bIter = b.iterator();
        Iterator<Tuple> rIter = rightAnswer.iterator();

        while (rIter.hasNext()) {
            assertTrue("bag ran out of tuples before answer", bIter.hasNext());
            assertEquals("tuples should be the same", bIter.next(), rIter.next());
        }

        assertFalse("right answer ran out of tuples before the bag",
            bIter.hasNext());
    }

}