/* 
 *  Copyright (C) 2000 - 2013 TagServlet Ltd
 *
 *  This file is part of Open BlueDragon (OpenBD) CFML Server Engine.
 *  
 *  OpenBD is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  Free Software Foundation,version 3.
 *  
 *  OpenBD is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *  
 *  You should have received a copy of the GNU General Public License
 *  along with OpenBD.  If not, see http://www.gnu.org/licenses/
 *  
 *  Additional permission under GNU GPL version 3 section 7
 *  
 *  If you modify this Program, or any covered work, by linking or combining 
 *  it with any of the JARS listed in the README.txt (or a modified version of 
 *  (that library), containing parts covered by the terms of that JAR, the 
 *  licensors of this Program grant you additional permission to convey the 
 *  resulting work. 
 *  README.txt @ http://www.openbluedragon.org/license/README.txt
 *  
 *  http://www.openbluedragon.org/
 *  
 *  $Id: fixEOL.java 2383 2013-06-16 23:04:20Z alan $
 */

package com.naryx.tagfusion.expression.function.string;

import com.naryx.tagfusion.cfm.engine.cfArgStructData;
import com.naryx.tagfusion.cfm.engine.cfData;
import com.naryx.tagfusion.cfm.engine.cfSession;
import com.naryx.tagfusion.cfm.engine.cfStringData;
import com.naryx.tagfusion.cfm.engine.cfmRunTimeException;
import com.naryx.tagfusion.expression.function.functionBase;

public class fixEOL extends functionBase {

	private static final long	serialVersionUID	= 1L;

	public fixEOL() {
		min = 1;
		max = 2;
		setNamedParams(new String[] { "string", "eolstyle" });
	}



	public String[] getParamInfo() {
		return new String[] { "string", "the type of EOL terminator to replace.  Valid values: LF, CRLF, SYSTEM (use the native property; default)" };
	}



	public java.util.Map getInfo() {
		return makeInfo("string", "Cleans up the EOL (End Of Line) separators for the given string, replacing where necessary", ReturnType.STRING);
	}



	public cfData execute(cfSession _session, cfArgStructData argStruct) throws cfmRunTimeException {
		String value 		= getNamedStringParam(argStruct, "string", "");
		String eolType	= getNamedStringParam(argStruct, "eolstyle", "system" ).toUpperCase();
		
		String eol	= System.getProperty("line.separator");
		if ( eolType.equals("LF") )
			eol	= "\n";
		else if (eolType.equals("CRLF") )
			eol = "\r\n";

		return new cfStringData( replaceLineBreaks(value, eol ) );
	}


	
	protected String replaceLineBreaks(String str, String EOL) {
		int len = str.length();
		StringBuffer buffer = new StringBuffer(len);
		for (int i = 0; i < len; i++) {
			char c = str.charAt(i);

			switch (c) {
				case '\n':
				case '\r':
					if ( (i + 1 < len) && (c == '\r' && str.charAt(i + 1) == '\n')) {
						i++;
					}

					buffer.append( EOL );
					break;
				default:
					buffer.append(c);
			}
		}

		return buffer.toString();
	}
}