package com.qxueyou.scc.exercise.service.impl.parser;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang3.StringUtils;

import com.qxueyou.scc.exercise.service.impl.Node;
import com.qxueyou.scc.exercise.service.impl.ParseResult;
import com.qxueyou.scc.exercise.service.impl.Parser;
import com.qxueyou.scc.exercise.service.impl.node.Item;

public class ItemAnalysisParser extends Parser {
	
	/**
	 * 解析字符串
	 */
	private String analysisStr = "解析";
	
	/**
	 * 解析字符串正则模式
	 */
	private Pattern analysis = Pattern.compile(analysisStr);
	

	@Override
	public ParseResult parse(Node node, String str) {
		return parseAnalysis((Item)node,str);
	}
	
	/**
	 * 解析 Item 参考答案
	 * 1.解析出类似  *** ( ab ) 这样的参考答案
	 * 2.将类似参考答案 ( ab ) 替换成 ( )
	 * @param item
	 * @param str
	 * @return
	 */
	private ParseResult parseAnalysis(Item item, String str) {
		
		//习题选项
		Matcher analysisMatch = analysis.matcher(str);
		
		//返回
		if(!matchBegin(analysisMatch)){
			return new ParseResult(false,ParseResult.STEP_CUR,null);
		}
		
		analysisMatch.reset();
		if(analysisMatch.find()){
			
			String group = analysisMatch.group();
			
			String analysisS = str.substring(group.length());
			
			if(StringUtils.isEmpty(item.getAnalysis())){
				item.setAnalysis(beautyContent(analysisS));
			}else{
				item.setAnalysis(item.getAnalysis().concat(beautyContent(analysisS)));
			}
			
		}
		
		//20150907修改：本来返回true，没有解析到一个类型，抛到上层
		return new ParseResult(false,ParseResult.STEP_CUR,null);
		
	}
	
	/**
	 * 去除文本中多余字符
	 * @param content
	 * @return
	 */
	private String beautyContent(String str){
		String prefix = "：:.。~、、．．";
		String content = str;
		while(content.length()>0 && prefix.contains(content.substring(0, 1))){
			content = content.substring(1);
		}
		return content;
	}
}