/*
 * Filename:     X3dDtdChecker.java
 * Created:      22 July 2004
 * Revised:       6 July 2005
 * Author:       Don Brutzman
 * Reference:    Mehran Habibi, Java Regular Expressions:  Taming the java.util.regex engine, Apress, Springer Verlag, NY, 2004.
 * Description:  Verify correct use of X3D final and transitional DTDs, convert .x3d file header if desired.
 * url:          http://www.web3d.org/x3d/content/X3dDtdChecker.java
 * 
 * Copyright (c) 1995-2006 held by the author(s).  All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer
 *       in the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the names of the Naval Postgraduate School (NPS)
 *       Modeling Virtual Environments and Simulation (MOVES) Institute
 *       (http://www.nps.edu and http://www.MovesInstitute.org)
 *       nor the names of its contributors may be used to endorse or
 *       promote products derived from this software without specific
 *       prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

import java.io.*;
import java.nio.*;
import java.nio.channels.*;
import java.text.DecimalFormat;
import java.util.*;
import java.util.regex.*;

/**
 *
 * @author  brutzman
 */
public class X3dDtdChecker {
    
    static String           UsageMessage   = "usage: java X3dDtdChecker sceneName.x3d [-setFinalDTD | -setTransitionalDTD]";
    static String           x3dFileName;
    static String           scene          = null;
    static String           revisedScene   = null;
    
    // removed final close bracket > so that files with embedded entity-reference declarations (such as examples/development/QuadTreeExamples) will work -->
    static final String     TRANSITIONAL_30_DOCTYPE = "<!DOCTYPE X3D PUBLIC \"http://www.web3d.org/specifications/x3d-3.0.dtd\" \"file:///www.web3d.org/TaskGroups/x3d/translation/x3d-3.0.dtd\"";
    static final String     TRANSITIONAL_31_DOCTYPE = "<!DOCTYPE X3D PUBLIC \"http://www.web3d.org/specifications/x3d-3.1.dtd\" \"file:///www.web3d.org/TaskGroups/x3d/translation/x3d-3.1.dtd\"";
    static final String     FINAL_30_DOCTYPE    = "<!DOCTYPE X3D PUBLIC \"ISO//Web3D//DTD X3D 3.0//EN\" \"http://www.web3d.org/specifications/x3d-3.0.dtd\"";
    static final String     FINAL_31_DOCTYPE    = "<!DOCTYPE X3D PUBLIC \"ISO//Web3D//DTD X3D 3.1//EN\" \"http://www.web3d.org/specifications/x3d-3.1.dtd\"";
    static final String     WarningComment = "<!--Warning:  transitional DOCTYPE in source .x3d file-->\n";
    static final String     WarningRegex   = "<!--Warning:  transitional DOCTYPE in source \\.x3d file-->(\\s)*";

    static boolean          setTransitionalDTD       = false;
    static boolean          setFinalDTD              = false;
    static boolean          foundNo_DTD              = false;
    static boolean          foundTransitional_30_DTD = false;
    static boolean          foundTransitional_31_DTD = false;
    static boolean          foundFinal_30_DTD        = false;
    static boolean          foundFinal_31_DTD        = false;
    static boolean          readOnlyFile             = false;
    static boolean          saveFile                 = true;
    
    static FileInputStream  fis;
    static RandomAccessFile raf;
    static FileChannel      fc;
    static ByteBuffer       bb;
   
    /**
     * extracts the content of a file
     * @param String fileName the name of the file to extract
     * @throws IOException
     * @return String representing contents of the file
     */
    public static String getFileContent(String fileName)
    {
    //  System.out.println("x3dFileName=" + fileName);
	// Must open as read-only FileInputStream first to ensure existence
	// before opening as read-write RandomAccessFile
	try 
	{
	    fis = new FileInputStream (fileName);
	    fis = null;
	}
	catch (FileNotFoundException fnf)
	{
	//  fnf.printStackTrace();
	    System.out.println("[Error] [X3dDtdChecker] scene \"" + fileName + "\" not found.");
	    System.out.println(UsageMessage);
	    saveFile = false;
	    exit (0);
	}
	try 
	{
	    raf = new RandomAccessFile (fileName, "rwd");
	    fc  = raf.getChannel();
	    bb  = ByteBuffer.allocate((int)fc.size());
	    fc.read(bb);
	    bb.flip();
	}
	catch (IOException ioe)
	{
	    readOnlyFile = true;
	//  ioe.printStackTrace();
	//  System.out.println();
	}
	if (raf == null) try 
	{
	    raf = new RandomAccessFile (fileName, "r");
	    fc  = raf.getChannel();
	    bb  = ByteBuffer.allocate((int)fc.size());
	    fc.read(bb);
	    bb.flip();
	    System.out.println("[Warning] [X3dDtdChecker] scene is read-only.");
	    System.out.println("          " + fileName);
	}
	catch (IOException ioe)
	{
	    System.out.println("[Error] [X3dDtdChecker] unable to read scene \"" + fileName + "\".");
	    ioe.printStackTrace();
	    System.out.println();
	    saveFile = false;
	    exit (0);
	}
	String returnString = new String (bb.array());
	bb = null;
	return returnString;
    }
    /**
     * resets the content of a file
     * @param String scene content being reset
     * @throws IOException
     * @return String representing contents of the file
     */
    public static void setFileContent(String revisedScene)
    {
	try 
	{
	    bb = ByteBuffer.wrap(revisedScene.getBytes());
	    fc.truncate(revisedScene.length());
	    fc.position(0);
	    fc.write(bb);
	}
	catch (IOException ioe)
	{
	    ioe.printStackTrace();
	}
	return;
    }
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args)
    {
	if ((args!= null) && (args.length >= 1) && (args.length <= 2))
	{
	    x3dFileName = args[0];
	}
	else
	{
	    System.out.println (UsageMessage);
	    saveFile = false;
	    exit (-1);
	}
	scene = getFileContent (x3dFileName);
	
	if (args!= null && args.length > 1)
	{
	    for (int i=1; i<=args.length-1; i++) 
	    {
	        if      ((args[i].compareTo("-f")==0) || (args[i].compareTo("-setFinalDTD")==0))
	        {
	            setFinalDTD = true;
	        }
	        else if ((args[i].compareTo("-t")==0) || (args[i].compareTo("-setTransitionalDTD")==0))
	        {
	            setTransitionalDTD = true;
	        }
	        else 
	        {
	            System.out.println("[Error] [X3dDtdChecker] unrecognized command-line option \"" + args[i] + "\"");
	            System.out.println(UsageMessage);
	            saveFile = false;
	            exit(-1);
	        }
	    }
	}
	if (setFinalDTD && setTransitionalDTD) 
	{
	    System.out.println ("[Error] [X3dDtdChecker] both -setFinalDTD and -setTransitionalDTD specified,");
	    System.out.println ("        only one operation allowed.");
	    System.out.println (UsageMessage);
	    saveFile = false;
	    exit (-1);
	}
//      System.out.println(scene); // input
	
	// had trouble with backreferencing group \1 and \2 to ensure matching single/double-quote characters :(
	String  regexXmlHeader   = "<\\?xml version=(\"|')1.(0|1)(\"|') encoding=(\"|')UTF-8(\"|')\\?>";
	Pattern patternXmlHeader = Pattern.compile(regexXmlHeader);
	Matcher matcherXmlHeader = patternXmlHeader.matcher(scene);
	if (matcherXmlHeader.find())
	{
	    System.out.print ("[X3dDtdChecker] valid XML declaration found");
	}
	else // no resetting of XML declaration performed
	{
	    System.out.println ("[Error] [X3dDtdChecker] no valid XML declaration found in scene!");
	    foundNo_DTD = true;
	    System.out.println(UsageMessage);
	    if (!setFinalDTD && !setTransitionalDTD) // force update if requested
	    {
	    	saveFile = false;
	   	exit (-1);
	    }
	}
	
	// does variable whitespace need to be handled?
	
	// removed final close bracket > so that files with embedded entity-reference declarations (such as examples/development/QuadTreeExamples) will work -->
	// <!DOCTYPE X3D PUBLIC "ISO//Web3D//DTD X3D 3.0//EN" "http://www.web3d.org/specifications/x3d-3.0.dtd">
	String  regexFinal30Doctype    = "<!DOCTYPE X3D PUBLIC(\\s)+\"ISO//Web3D//DTD X3D 3.0//EN\"(\\s)+\"http://www.web3d.org/specifications/x3d-3.0.dtd\"(\\s)*";
	Pattern patternFinal30Doctype  = Pattern.compile(regexFinal30Doctype);
	Matcher matcherFinal30Doctype  = patternFinal30Doctype.matcher(scene);

	String  regexFinal31Doctype = "<!DOCTYPE X3D PUBLIC(\\s)+\"ISO//Web3D//DTD X3D 3.1//EN\"(\\s)+\"http://www.web3d.org/specifications/x3d-3.1.dtd\"(\\s)*";
	Pattern patternFinal31Doctype  = Pattern.compile(regexFinal31Doctype);
	Matcher matcherFinal31Doctype  = patternFinal31Doctype.matcher(scene);

	// <!DOCTYPE X3D PUBLIC "http://www.web3d.org/specifications/x3d-3.0.dtd" "file:///www.web3d.org/TaskGroups/x3d/translation/x3d-3.0.dtd">
	String  regexTransitional30Doctype   = "<!DOCTYPE X3D PUBLIC(\\s)+\"http://www.web3d.org/specifications/x3d-3.0.dtd\"(\\s)+\"file:///www.web3d.org/TaskGroups/x3d/translation/x3d-3.0.dtd\"(\\s)*";
	Pattern patternTransitional30Doctype = Pattern.compile(regexTransitional30Doctype);
	Matcher matcherTransitional30Doctype = patternTransitional30Doctype.matcher(scene);
	
	String  regexTransitional31Doctype   = "<!DOCTYPE X3D PUBLIC(\\s)+\"http://www.web3d.org/specifications/x3d-3.1.dtd\"(\\s)+\"file:///www.web3d.org/TaskGroups/x3d/translation/x3d-3.1.dtd\"(\\s)*";
	Pattern patternTransitional31Doctype = Pattern.compile(regexTransitional31Doctype);
	Matcher matcherTransitional31Doctype = patternTransitional31Doctype.matcher(scene);
	
	String  regexAnyDoctype   = "<!DOCTYPE X3D PUBLIC";
	Pattern patternAnyDoctype = Pattern.compile(regexAnyDoctype);
	Matcher matcherAnyDoctype = patternAnyDoctype.matcher(scene);
	
	if      (matcherFinal30Doctype.find())
	{
	    foundFinal_30_DTD = true;
	    System.out.println (", final X3D 3.0 DOCTYPE found.");
	    System.out.println(FINAL_30_DOCTYPE+">");
	}
	else if      (matcherFinal31Doctype.find())
	{
	    foundFinal_31_DTD = true;
	    System.out.println (", final X3D 3.1 DOCTYPE found.");
	    System.out.println(FINAL_31_DOCTYPE+">");
	}
	else if (matcherTransitional30Doctype.find())
	{
	    foundTransitional_30_DTD = true;
	    System.out.println (", transitional X3D 3.0 DOCTYPE found.");
	    System.out.println(TRANSITIONAL_30_DOCTYPE+">");
	}
	else if (matcherTransitional31Doctype.find())
	{
	    foundTransitional_31_DTD = true;
	    System.out.println (", transitional X3D 3.1 DOCTYPE found.");
	    System.out.println(TRANSITIONAL_31_DOCTYPE+">");
	}
	else if (matcherAnyDoctype.find())
	{
	    System.out.println ("\n[Error] Nonstandard X3D DOCTYPE found!");
	    saveFile = false;
	    exit (-1);
	}
	else
	{
	    System.out.println ("\n[Error] No X3D DOCTYPE found!");
	    foundNo_DTD = true;
	    if (!setFinalDTD && !setTransitionalDTD) // force update if requested
	    {
	    	saveFile = false;
	   	exit (-1);
	    }
	}
	// check for multiple DOCTYPEs present
	matcherAnyDoctype.reset();
	int matchCount = 0;
	while (matcherAnyDoctype.find())
	{
	    matchCount++; 
	}
	if (matchCount > 1)
	{
	    System.out.print ("[Warning] Multiple X3D DOCTYPEs found (" + matchCount + " total)");
	    if ((setFinalDTD || setTransitionalDTD) && (readOnlyFile == false))
	    {
	         System.out.println (", no DTD conversion attempted.");
	    }
	    else System.out.println (".");
	    saveFile = false;
	    exit (-1);
	}
	if (readOnlyFile)
	{
	    saveFile = false;
	    exit (0); // application complete
	}
	
	if      (setFinalDTD)         System.out.print ("[X3dDtdChecker] set final DTD:  ");
	else if (setTransitionalDTD)  System.out.print ("[X3dDtdChecker] set transitional DTD:  ");
	
	if      (setFinalDTD && foundTransitional_30_DTD)
	{
	    matcherTransitional30Doctype.reset();
	    revisedScene = matcherTransitional30Doctype.replaceFirst (FINAL_30_DOCTYPE);
	    revisedScene = revisedScene.replaceAll (WarningRegex,"");  // also remove warning comment
	    System.out.println("scene reset to final X3D 3.0 DTD.");
	    System.out.println(FINAL_30_DOCTYPE+">");
	    saveFile = true;
	}
	else if (setFinalDTD && foundTransitional_31_DTD)
	{
	    matcherTransitional31Doctype.reset();
	    revisedScene = matcherTransitional31Doctype.replaceFirst (FINAL_31_DOCTYPE);
	    revisedScene = revisedScene.replaceAll (WarningRegex,"");  // also remove warning comment
	    System.out.println("scene reset to final X3D 3.1 DTD.");
	    System.out.println(FINAL_31_DOCTYPE+">");
	    saveFile = true;
	}
	else if (setTransitionalDTD && foundFinal_30_DTD)
	{
	    matcherFinal30Doctype.reset();
	    revisedScene = matcherFinal30Doctype.replaceFirst (WarningComment + TRANSITIONAL_30_DOCTYPE);
	    System.out.println("scene reset to transitional X3D DTD.");
	    System.out.println(TRANSITIONAL_30_DOCTYPE+">");
	    saveFile = true;
	}
	else if (setTransitionalDTD && foundFinal_31_DTD)
	{
	    matcherFinal31Doctype.reset();
	    revisedScene = matcherFinal31Doctype.replaceFirst (WarningComment + TRANSITIONAL_31_DOCTYPE);
	    System.out.println("scene reset to transitional X3D DTD.");
	    System.out.println(TRANSITIONAL_31_DOCTYPE+">");
	    saveFile = true;
	}
	else if (foundNo_DTD)
	{
		System.out.println ("no action taken, functionality not yet implemented...");
	    	saveFile = false;
	}
	else if (setFinalDTD || setTransitionalDTD)
	{
		System.out.println ("no action necessary.");
	    	saveFile = false;
	}
	exit (0); // application complete
    }
    public static void exit (int exitCode)
    {
    	if (saveFile == false)  System.exit(exitCode);
	if (setFinalDTD || setTransitionalDTD) setFileContent (revisedScene);
	try
	{
	    if (fc != null) 
	    {
	        fc.close();
	        fc = null;
	    }
	}
	catch (IOException ioe)
	{
	    ioe.printStackTrace();
	    System.exit(exitCode);
	}
	System.out.println();
	System.exit(exitCode);
    }
}