/*
 * 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 static org.junit.Assert.assertTrue;

import java.util.Map;
import java.util.Random;

import org.apache.pig.backend.executionengine.ExecException;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.Result;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.ConstantExpression;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.POIsNull;
import org.apache.pig.data.DataBag;
import org.apache.pig.data.DataByteArray;
import org.apache.pig.data.DataType;
import org.apache.pig.data.Tuple;
import org.apache.pig.data.TupleFactory;
import org.apache.pig.test.utils.GenPhyOp;
import org.apache.pig.test.utils.GenRandomData;
import org.joda.time.DateTime;
import org.junit.Test;

public class TestNull {
    public static boolean test(byte type) throws ExecException {
        Random r = new Random();
        ConstantExpression lt = (ConstantExpression)GenPhyOp.exprConst();
        lt.setResultType(type);
        Tuple dummyTuple = TupleFactory.getInstance().newTuple(1);
        lt.attachInput(dummyTuple);
        POIsNull isNullExpr = (POIsNull)GenPhyOp.compIsNullExpr();
        isNullExpr.setExpr(lt);
        isNullExpr.setOperandType(type);

        Object inp1;
        Result res;
        Boolean ret;
        switch (type) {
        case DataType.BAG:
            inp1 = GenRandomData.genRandSmallTupDataBag(r, 10, 100);
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!res.result.equals(ret))
                return false;
            // set the input to null and test
            lt.setValue((DataBag)null);
            res = isNullExpr.getNextBoolean();
            if (!res.result.equals(true))
                return false;
            return true;
        case DataType.BOOLEAN:
            inp1 = r.nextBoolean();
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(ret)))
                return false;
            // set the input to null and test
            lt.setValue((Boolean)null);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(true)))
                return false;
            return true;
        case DataType.BYTEARRAY:
            inp1 = GenRandomData.genRandDBA(r);
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(ret)))
                return false;
            // set the input to null and test
            lt.setValue((DataByteArray)null);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(true)))
                return false;
            return true;
        case DataType.CHARARRAY:
            inp1 = GenRandomData.genRandString(r);
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(ret)))
                return false;
            // set the input to null and test
            lt.setValue((String)null);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(true)))
                return false;
            return true;
        case DataType.DOUBLE:
            inp1 = r.nextDouble();
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(ret)))
                return false;
            // set the input to null and test
            lt.setValue((Double)null);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(true)))
                return false;
            return true;
        case DataType.FLOAT:
            inp1 = r.nextFloat();
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(ret)))
                return false;
            // set the input to null and test
            lt.setValue((Float)null);
            res = isNullExpr.getNextBoolean();
            if (!res.result.equals(true))
                return false;
            return true;
        case DataType.INTEGER:
            inp1 = r.nextInt();
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(ret)))
                return false;
            // set the input to null and test
            lt.setValue((Integer)null);
            res = isNullExpr.getNextBoolean();
            if (!res.result.equals(true))
                return false;
            return true;
        case DataType.LONG:
            inp1 = r.nextLong();
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(ret)))
                return false;
            // set the input to null and test
            lt.setValue((Long)null);
            res = isNullExpr.getNextBoolean();
            if (!res.result.equals(true))
                return false;
            return true;
        case DataType.DATETIME:
            inp1 = new DateTime(r.nextLong());
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(ret)))
                return false;
            // set the input to null and test
            lt.setValue((DateTime)null);
            res = isNullExpr.getNextBoolean();
            if (!res.result.equals(true))
                return false;
            return true;
        case DataType.MAP:
            inp1 = GenRandomData.genRandMap(r, 10);
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(ret)))
                return false;
            // set the input to null and test
            lt.setValue((Map)null);
            res = isNullExpr.getNextBoolean();
            if (!res.result.equals(true))
                return false;
            return true;
        case DataType.TUPLE:
            inp1 = GenRandomData.genRandSmallBagTuple(r, 10, 100);
            res = isNullExpr.getNextBoolean();
            if ((Boolean)res.result != true)
                return false;
            lt.setValue(inp1);
            res = isNullExpr.getNextBoolean();
            ret = (DataType.compare(inp1, null) == 0);
            if (!(res.result.equals(ret)))
                return false;
            // set the input to null and test
            lt.setValue((Tuple)null);
            res = isNullExpr.getNextBoolean();
            if (!res.result.equals(true))
                return false;
            return true;
        }
        return true;
    }
    
    @Test
    public void testCompare() {
        Object o1 = new Object();
        Object o2 = null;
        assertTrue(DataType.compare(o1, o2, DataType.NULL, DataType.NULL) > 0);

        o1 = null;
        o2 = new Object();
        assertTrue(DataType.compare(o1, o2, DataType.NULL, DataType.NULL) < 0);

        o1 = null;
        o2 = null;
        assertTrue(DataType.compare(o1, o2, DataType.NULL, DataType.NULL) == 0);
    }

    @Test
    public void testOperator() throws ExecException {
        int TRIALS = 10;
        byte[] types = DataType.genAllTypes();
        Map<Byte, String> map = DataType.genTypeToNameMap();
        // System.out.println("Testing Not Equal To Expression:");

        long t1 = System.currentTimeMillis();

        for (byte b : types) {
            // System.out.print("\t With " + map.get(b) + ": ");
            for (int i = 0; i < TRIALS; i++) {
                assertTrue(test(b));
            }
            /*
             * if (succ) System.out.println("Success!!"); else
             * System.out.println("Failure");
             */
        }
    }
}