/**
 * Copyright 2007 The Apache Software Foundation
 *
 * Licensed 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 net.paoding.analysis.analyzer;

import java.util.Properties;

import net.paoding.analysis.Constants;
import net.paoding.analysis.analyzer.estimate.TryPaodingAnalyzer;
import net.paoding.analysis.knife.Knife;
import net.paoding.analysis.knife.Paoding;
import net.paoding.analysis.knife.PaodingMaker;

/**
 * PaodingAnalyzer是基于“庖丁解牛”框架的Lucene詞語分析器，是“庖丁解?！笨蚣軐ucene的適配器。
 * <p>
 * 
 * PaodingAnalyzer是線程安全的：并發情況下使用同一個PaodingAnalyzer實例是可行的。<br>
 * PaodingAnalyzer是可復用的：推薦多次同一個PaodingAnalyzer實例。
 * <p>
 * 
 * PaodingAnalyzer自動讀取類路徑下的paoding-analysis.properties屬性文件，裝配PaodingAnalyzer
 * <p>
 * 
 * @author Zhiliang Wang [qieqie.wang@gmail.com]
 * 
 * @see PaodingAnalyzerBean
 * 
 * @since 1.0
 * 
 */
public class PaodingAnalyzer extends PaodingAnalyzerBean {

	/**
	 * 根據類路徑下的paoding-analysis.properties構建一個PaodingAnalyzer對象
	 * <p>
	 * 在一個JVM中，可多次創建，而并不會多次讀取屬性文件，不會重復讀取字典。
	 */
	public PaodingAnalyzer() {
		this(PaodingMaker.DEFAULT_PROPERTIES_PATH);
	}

	/**
	 * @param propertiesPath null表示使用類路徑下的paoding-analysis.properties
	 */
	public PaodingAnalyzer(String propertiesPath) {
		init(propertiesPath);
	}

	protected void init(String propertiesPath) {
		// 根據PaodingMaker說明，
		// 1、多次調用getProperties()，返回的都是同一個properties實例(只要屬性文件沒發生過修改)
		// 2、相同的properties實例，PaodingMaker也將返回同一個Paoding實例
		// 根據以上1、2點說明，在此能夠保證多次創建PaodingAnalyzer并不會多次裝載屬性文件和詞典
		if (propertiesPath == null) {
			propertiesPath = PaodingMaker.DEFAULT_PROPERTIES_PATH;
		}
		Properties properties = PaodingMaker.getProperties(propertiesPath);
		String mode = Constants
				.getProperty(properties, Constants.ANALYZER_MODE);
		Paoding paoding = PaodingMaker.make(properties);
		setKnife(paoding);
		setMode(mode);
	}

	/**
	 * 本方法為PaodingAnalyzer附帶的測試評估方法。 <br>
	 * 執行之可以查看分詞效果。以下任選一種方式進行:
	 * <p>
	 * 
	 * java net...PaodingAnalyzer<br>
	 * java net...PaodingAnalyzer --help<br>
	 * java net...PaodingAnalyzer 中華人民共和國<br>
	 * java net...PaodingAnalyzer -m max 中華人民共和國<br>
	 * java net...PaodingAnalyzer -f c:/text.txt<br>
	 * java net...PaodingAnalyzer -f c:/text.txt -c utf-8<br>
	 * 
	 * @param args
	 */
	public static void main(String[] args) {
		if (System.getProperty("paoding.try.app") == null) {
			System.setProperty("paoding.try.app", PaodingAnalyzer.class.getSimpleName());
			System.setProperty("paoding.try.cmd", "java " + PaodingAnalyzer.class.getName());
		}
		TryPaodingAnalyzer.main(args);
	}

	// --------------------------------------------------

	/**
	 * @param knife
	 * @param default_mode
	 * @deprecated
	 */
	public PaodingAnalyzer(Knife knife, int mode) {
		super(knife, mode);
	}

	/**
	 * 等價于maxMode()
	 * 
	 * @param knife
	 * @return
	 * @deprecated
	 */
	public static PaodingAnalyzer queryMode(Knife knife) {
		return maxMode(knife);
	}

	/**
	 * 
	 * @param knife
	 * @return
	 * @deprecated
	 */
	public static PaodingAnalyzer defaultMode(Knife knife) {
		return new PaodingAnalyzer(knife, MOST_WORDS_MODE);
	}

	/**
	 * 
	 * @param knife
	 * @return
	 * @deprecated
	 */
	public static PaodingAnalyzer maxMode(Knife knife) {
		return new PaodingAnalyzer(knife, MAX_WORD_LENGTH_MODE);
	}

	/**
	 * 等價于defaultMode()
	 * 
	 * @param knife
	 * @return
	 * @deprecated
	 * 
	 */
	public static PaodingAnalyzer writerMode(Knife knife) {
		return defaultMode(knife);
	}
}