/*
 * 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.jena.hadoop.rdf.mapreduce.filter;

import java.io.IOException;

import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.mrunit.mapreduce.MapDriver;
import org.apache.jena.hadoop.rdf.mapreduce.AbstractMapperTests;
import org.apache.jena.hadoop.rdf.mapreduce.filter.AbstractNodeTupleFilterMapper;
import org.apache.jena.hadoop.rdf.types.AbstractNodeTupleWritable;
import org.junit.Test;


/**
 * Abstract tests for {@link AbstractNodeTupleFilterMapper} implementations
 * which filter based on the validity of tuples
 * 
 * 
 * 
 * @param <TValue>
 *            Tuple type
 * @param <T>
 *            Writable tuple type
 */
public abstract class AbstractNodeTupleFilterTests<TValue, T extends AbstractNodeTupleWritable<TValue>> extends
        AbstractMapperTests<LongWritable, T, LongWritable, T> {

    protected final void generateData(MapDriver<LongWritable, T, LongWritable, T> driver, int num) {
        for (int i = 0; i < num; i++) {
            LongWritable key = new LongWritable(i);
            if (i % 2 == 0 && !this.noValidInputs()) {
                T value = this.createValidValue(i);
                driver.addInput(key, value);
                if (!this.isInverted())
                    driver.addOutput(key, value);
            } else {
                T value = this.createInvalidValue(i);
                driver.addInput(key, value);
                if (this.isInverted())
                    driver.addOutput(key, value);
            }
        }
    }

    /**
     * Method that may be overridden for testing filters where all the generated
     * data will be rejected as invalid
     * 
     * @return True if there are no valid inputs, false otherwise (default)
     */
    protected boolean noValidInputs() {
        return false;
    }

    /**
     * Method that may be overridden for testing filters with inverted mode
     * enabled i.e. where normally valid input is considered invalid and vice
     * versa
     * 
     * @return True if inverted, false otherwise (default)
     */
    protected boolean isInverted() {
        return false;
    }

    /**
     * Creates an invalid value
     * 
     * @param i
     *            Key
     * @return Invalid value
     */
    protected abstract T createInvalidValue(int i);

    /**
     * Creates a valid value
     * 
     * @param i
     *            Key
     * @return Valid value
     */
    protected abstract T createValidValue(int i);

    protected final void testFilterValid(int num) throws IOException {
        MapDriver<LongWritable, T, LongWritable, T> driver = this.getMapDriver();
        this.generateData(driver, num);
        driver.runTest();
    }

    /**
     * Test splitting tuples into their constituent nodes
     * 
     * @throws IOException
     */
    @Test
    public final void filter_valid_01() throws IOException {
        this.testFilterValid(1);
    }

    /**
     * Test splitting tuples into their constituent nodes
     * 
     * @throws IOException
     */
    @Test
    public final void filter_valid_02() throws IOException {
        this.testFilterValid(100);
    }

    /**
     * Test splitting tuples into their constituent nodes
     * 
     * @throws IOException
     */
    @Test
    public final void filter_valid_03() throws IOException {
        this.testFilterValid(1000);
    }

    /**
     * Test splitting tuples into their constituent nodes
     * 
     * @throws IOException
     */
    @Test
    public final void filter_valid_04() throws IOException {
        this.testFilterValid(2500);
    }
}