/**
 * 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.solr.analysis;

import org.apache.solr.common.ResourceLoader;
import org.apache.solr.common.util.StrUtils;
import org.apache.solr.core.Config;
import org.apache.solr.schema.IndexSchema;

import java.io.IOException;
import java.util.List;
import java.util.Map;

import org.apache.lucene.analysis.CharArraySet;
import org.apache.lucene.analysis.StopFilter;
import org.apache.lucene.util.Version;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Simple abstract implementation that handles init arg processing, is not really
 * a factory as it implements no interface, but removes code duplication
 * in its subclasses.
 * 
 * @version $Id: BaseTokenStreamFactory.java 1060039 2011-01-17 18:38:23Z rmuir $
 */
abstract class BaseTokenStreamFactory {
  /** The init args */
  protected Map<String,String> args;
  
  /** the luceneVersion arg */
  protected Version luceneMatchVersion = null;

  public static final Logger log = LoggerFactory.getLogger(BaseTokenStreamFactory.class);

  public void init(Map<String,String> args) {
    this.args=args;
    String matchVersion = args.get(IndexSchema.LUCENE_MATCH_VERSION_PARAM);
    if (matchVersion != null) {
      luceneMatchVersion = Config.parseLuceneVersionString(matchVersion);
    }
  }

  public Map<String,String> getArgs() {
    return args;
  }
  
  /** this method can be called in the {@link TokenizerFactory#create(java.io.Reader)} 
   * or {@link TokenFilterFactory#create(org.apache.lucene.analysis.TokenStream)} methods,
   * to inform user, that for this factory a {@link #luceneMatchVersion} is required */
  protected final void assureMatchVersion() {
    if (luceneMatchVersion == null) {
      throw new RuntimeException("Configuration Error: Factory '" + this.getClass().getName() +
        "' needs a 'luceneMatchVersion' parameter");
    } else if (!luceneMatchVersion.onOrAfter(Version.LUCENE_30)) {
      log.warn(getClass().getSimpleName() + " is using deprecated " + luceneMatchVersion + 
        " emulation. You should at some point declare and reindex to at least 3.0, because " +
        "2.x emulation is deprecated and will be removed in 4.0");
    }
  }

  protected final void warnDeprecated(String message) {
    log.warn(getClass().getSimpleName() + " is deprecated. " + message);
  }
  
  // TODO: move these somewhere that tokenizers and others
  // can also use them...
  protected int getInt(String name) {
    return getInt(name,-1,false);
  }

  protected int getInt(String name, int defaultVal) {
    return getInt(name,defaultVal,true);
  }

  protected int getInt(String name, int defaultVal, boolean useDefault) {
    String s = args.get(name);
    if (s==null) {
      if (useDefault) return defaultVal;
      throw new RuntimeException("Configuration Error: missing parameter '" + name + "'");
    }
    return Integer.parseInt(s);
  }

  protected boolean getBoolean(String name, boolean defaultVal) {
    return getBoolean(name,defaultVal,true);
  }

  protected boolean getBoolean(String name, boolean defaultVal, boolean useDefault) {
    String s = args.get(name);
    if (s==null) {
      if (useDefault) return defaultVal;
      throw new RuntimeException("Configuration Error: missing parameter '" + name + "'");
    }
    return Boolean.parseBoolean(s);
  }

  protected CharArraySet getWordSet(ResourceLoader loader,
      String wordFiles, boolean ignoreCase) throws IOException {
    assureMatchVersion();
    List<String> files = StrUtils.splitFileNames(wordFiles);
    CharArraySet words = null;
    if (files.size() > 0) {
      // default stopwords list has 35 or so words, but maybe don't make it that
      // big to start
      words = new CharArraySet(luceneMatchVersion, 
          files.size() * 10, ignoreCase);
      for (String file : files) {
        List<String> wlist = loader.getLines(file.trim());
        words.addAll(StopFilter.makeStopSet(luceneMatchVersion, wlist,
            ignoreCase));
      }
    }
    return words;
  }
}