/**
 * Copyright (c) 2012, The University of Southampton and the individual contributors.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *   *  Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *
 *   *  Redistributions in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the documentation
 *      and/or other materials provided with the distribution.
 *
 *   *  Neither the name of the University of Southampton nor the names of its
 *      contributors may be used to endorse or promote products derived from this
 *      software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.openimaj.tools.twitter.modes.filter;

import java.util.ArrayList;
import java.util.List;

import org.arabidopsis.ahocorasick.AhoCorasick;
import org.kohsuke.args4j.Option;
import org.kohsuke.args4j.ProxyOptionHandler;
import org.openimaj.twitter.USMFStatus;

/**
 * The grep functionality. Should only be used as a post filter most of the time
 * @author Sina Samangooei (ss@ecs.soton.ac.uk)
 *
 */
public class GrepFilter extends TwitterPreprocessingPredicate {

        @Option(name="--string-match", aliases="-sm", required=false, usage="Match these strings exactly, uses aho-corasick", metaVar="STRING", multiValued=true)
        List<String> stringMatch = new ArrayList<String>();
        AhoCorasick<String> searcher = null;

        @Option(name="--regexes", aliases="-r", required=false, usage="Match these regexes. Uses java pattern", metaVar="STRING", multiValued=true)
        List<String> regexStrings = new ArrayList<String>();

        @Option(name="--regex-engine", aliases="-rege", required=false, usage="The regex engine used to resolve matches", metaVar="STRING",handler=ProxyOptionHandler.class)
        RegexEngineMode regexEngine = RegexEngineMode.JAVA;
        RegexEngine regexEngineOp = RegexEngineMode.JAVA.getOptions();

        @Override
        public boolean test(USMFStatus twitterStatus) {
                String text = twitterStatus.text.toLowerCase();
                boolean match = searcher.search(text.getBytes()).hasNext();
                if(match) return match;
                // now do the slower regexes if there are any
                match = this.regexEngineOp.matches(text);
                return match; // must be false
        }

        @Override
        public void validate() {
                searcher = new AhoCorasick<String>();
                for (String match : this.stringMatch) {
                        searcher.add(match.toLowerCase().getBytes(), match);
                }
                searcher.prepare();

                for (String pat : this.regexStrings) {
                        this.regexEngineOp.add(pat);
                }
        }
}