package com.smtscript.lib.regex;

import java.util.regex.Matcher;

import org.mozilla.javascript.Context;
import org.mozilla.javascript.NativeFunction;
import org.mozilla.javascript.Wrapper;

public class JSRegexMatcher 
{
	protected JSRegex _parentRegex;
	protected Matcher _matcher;
	
	public JSRegexMatcher(JSRegex jsRegex, Matcher matcher)
	{
		_parentRegex = jsRegex;
		_matcher = matcher;
	}
	
	public boolean find()
	{
		return _matcher.find();
	}
	
	public String group(int index)
	{
		return _matcher.group(index);
	}
	
	public int start(int group)
	{
		return _matcher.start(group);
	}
	
	public int end(int group)
	{
		return _matcher.end(group);
	}
	
	public String replace(Object replace) throws Exception
	{
		if(replace instanceof Wrapper)
			replace = ((Wrapper)replace).unwrap();
		
		if(replace instanceof String)
		{
			return _matcher.replaceAll((String)replace);
		}
		else if(replace instanceof NativeFunction)
		{
			Context cx = _parentRegex.__parentScope__().__runtime__().entryContext();
			
			try
			{
				Object[] args = new Object[]{this};
				StringBuffer sb = new StringBuffer();
				while (_matcher.find()) 
				{
					Object value = ((NativeFunction)replace).call(cx, ((NativeFunction)replace), null, args);
					_matcher.appendReplacement(sb, value.toString());
				}
				_matcher.appendTail(sb);
				
				return sb.toString();
			}
			finally
			{
				Context.exit();
			}
		}
		else
			throw new Exception("unsupport replace type : " + replace.getClass().getName());
	}
}