package com.jclark.xsl.sax;

import org.xml.sax.*;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.File;
import java.io.FileDescriptor;
import java.net.URL;

public class Driver {
  static class ErrorHandlerImpl implements ErrorHandler {
    public void warning(SAXParseException e) {
      printSAXParseException(e);
    }
    public void error(SAXParseException e) {
      printSAXParseException(e);
    }
    public void fatalError(SAXParseException e) throws SAXException {
      throw e;
    }
  }

  public static void main(String[] args) {
    XSLProcessorImpl xsl = new XSLProcessorImpl();
    setParser(xsl);
    xsl.setErrorHandler(new ErrorHandlerImpl());
    int nArgs = 0;
    for (int i = 0; i < args.length; i++) {
      int k = args[i].indexOf('=');
      if (k > 0)
	xsl.setParameter(args[i].substring(0, k),
			 args[i].substring(k + 1));
      else
	args[nArgs++] = args[i];
    }

    if (nArgs != 2 && nArgs != 3) {
      System.err.println("usage: java com.jclark.xsl.sax.Driver source stylesheet [result] [param=value]...");
      System.exit(1);
    }

    OutputMethodHandlerImpl outputMethodHandler = new OutputMethodHandlerImpl(xsl);
    xsl.setOutputMethodHandler(outputMethodHandler);
    boolean succeeded = true;
    File in = new File(args[0]);
    File stylesheet = new File(args[1]);
    File out = nArgs == 3 ? new File(args[2]) : null;
    if (!in.isDirectory())
      succeeded = transformFile(xsl, outputMethodHandler, in, stylesheet, out);
    else {
      String[] inFiles = in.list();
      for (int i = 0; i < inFiles.length; i++) {
	File inFile = new File(in, inFiles[i]);
	if (!inFile.isDirectory()) {
	  if (!stylesheet.isDirectory()) {
	    // FIXME optimize this case by loading the stylesheet only once
	    if (!transformFile(xsl, outputMethodHandler,
			       inFile, stylesheet, new File(out, inFiles[i])))
	      succeeded = false;
	  }
	  else {
	    int ext = inFiles[i].lastIndexOf('.');
	    File stylesheetFile
	      = new File(stylesheet,
			 ext < 0
			 ? inFiles[i]
			 : inFiles[i].substring(0, ext) + ".xsl");
	    if (stylesheetFile.exists()
		&& !transformFile(xsl,
				  outputMethodHandler,
				  inFile,
				  stylesheetFile,
				  new File(out, inFiles[i])))
	      succeeded = false;
	  }
	}
      }
    }
    if (!succeeded)
      System.exit(1);
  }

  static boolean transformFile(XSLProcessor xsl,
			       OutputMethodHandlerImpl outputMethodHandler,
			       File inputFile,
			       File stylesheetFile,
			       File outputFile) {
    Destination dest;
    if (outputFile == null)
      dest = new FileDescriptorDestination(FileDescriptor.out);
    else
      dest = new FileDestination(outputFile);
    outputMethodHandler.setDestination(dest);
    return transform(xsl,
		     fileInputSource(stylesheetFile),
		     fileInputSource(inputFile));
  }

  static boolean transform(XSLProcessor xsl,
			   InputSource stylesheetSource,
			   InputSource inputSource) {
    try {
      xsl.loadStylesheet(stylesheetSource);
      xsl.parse(inputSource);
      return true;
    }
    catch (SAXParseException e) {
      printSAXParseException(e);
    }
    catch (SAXException e) {
      System.err.println(e.getMessage());
    }
    catch (IOException e) {
      System.err.println(e.toString());
    }
    return false;
  }

  static void printSAXParseException(SAXParseException e) {
    String systemId = e.getSystemId();
    int lineNumber = e.getLineNumber();
    if (systemId != null)
      System.err.print(systemId + ":");
    if (lineNumber >= 0)
      System.err.print(lineNumber + ":");
    if (systemId != null || lineNumber >= 0)
      System.err.print(" ");
    System.err.println(e.getMessage());
  }

  static void setParser(XSLProcessorImpl xsl) {
    String parserClass = System.getProperty("com.jclark.xsl.sax.parser");
    if (parserClass == null)
      parserClass = System.getProperty("org.xml.sax.parser");
    if (parserClass == null)
      parserClass = "com.jclark.xml.sax.CommentDriver";
    try {
      Object parserObj = Class.forName(parserClass).newInstance();
      if (parserObj instanceof XMLProcessorEx)
	xsl.setParser((XMLProcessorEx)parserObj);
      else
	xsl.setParser((Parser)parserObj);
      return;
    }
    catch (ClassNotFoundException e) {
      System.err.println(e.toString());
    }
    catch (InstantiationException e) {
      System.err.println(e.toString());
    }
    catch (IllegalAccessException e) {
      System.err.println(e.toString());
    }
    catch (ClassCastException e) {
      System.err.println(parserClass + " is not a SAX driver");
    }
    System.exit(1);
  }

  /**
   * Generates an <code>InputSource</code> from a file name.
   */
  static public InputSource fileInputSource(String str) {
    return fileInputSource(new File(str));
  }

  static public InputSource fileInputSource(File file) {
    String path = file.getAbsolutePath();
    String fSep = System.getProperty("file.separator");
    if (fSep != null && fSep.length() == 1)
      path = path.replace(fSep.charAt(0), '/');
    if (path.length() > 0 && path.charAt(0) != '/')
      path = '/' + path;
    try {
      return new InputSource(new URL("file", "", path).toString());
    }
    catch (java.net.MalformedURLException e) {
      /* According to the spec this could only happen if the file
	 protocol were not recognized. */
      throw new Error("unexpected MalformedURLException");
    }
  }

}