/*
 *    GSFile.java
 *    Copyright (C) 2002 New Zealand Digital Library, http://www.nzdl.org
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program 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 this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
package org.greenstone.gsdl3.util;

import java.io.File; 
import org.apache.soap.encoding.soapenc.Base64;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.IOException;
import java.lang.ClassLoader; // to find files on the class path
import java.net.URL;

/**
 * GSFile - utility class for Greenstone.
 *
 * all file paths are created here
 * also has file utility methods
 *
 * @author <a href="mailto:kjdon@cs.waikato.ac.nz">Katherine Don</a>
 * @version $Revision: 5109 $
 * @see File
 */

public class GSFile {

    static public String dtdDir(String gsdl3_home) {
	return gsdl3_home + File.separatorChar + "resources" +
	    File.separatorChar + "dtd";
    }
    /**  site config file path */
    static public String siteConfigFile(String site_home) {
	return site_home + File.separatorChar+"siteConfig.xml";

    }
    /**  interface config file path */
    static public String interfaceConfigFile(String interface_home) {
	return interface_home + File.separatorChar+"interfaceConfig.xml";

    }

    /** collection directory path */
    static public String collectDir(String site_home) {
	return site_home+File.separatorChar+"collect";
    }
    
    
    /** collection config file path*/
    static public String collectionConfigFile(String site_home, 
					      String collection_name) {
	return site_home+File.separatorChar+"collect"+
			File.separatorChar+collection_name+
			File.separatorChar+"etc"+
			File.separatorChar+"collectionConfig.xml";

    }
    /** collection init file path*/
    static public String collectionInitFile(String site_home, 
					    String collection_name) {
	return site_home+File.separatorChar+"collect"+
			File.separatorChar+collection_name+
			File.separatorChar+"etc"+
			File.separatorChar+"collectionInit.xml";

    }

    /** collection build config file path*/
    static public String collectionBuildConfigFile(String site_home, 
						   String collection_name ) {
	return site_home+File.separatorChar+"collect"+
			File.separatorChar+collection_name+
			File.separatorChar+"index"+
			File.separatorChar+"buildConfig.xml";
    }
    /** collection build config file path*/
    static public String collectionBuildConfigFileBuilding(String site_home, 
						   String collection_name ) {
	return site_home+File.separatorChar+"collect"+
			File.separatorChar+collection_name+
			File.separatorChar+"building"+
			File.separatorChar+"buildConfig.xml";
    }

    /** XML Transform directory path */
    static public String xmlTransformDir(String interface_home) {
	return interface_home+File.separatorChar+"transform";
    }

    /** collection base directory path */	 
    static public String collectionBaseDir(String site_home,
					   String collection_name) {
	return site_home+File.separatorChar+"collect"+
	    File.separatorChar+collection_name;
    }
    /** collection building directory path */	 
    static public String collectionBuildDir(String site_home,
					   String collection_name) {
	return collectionBaseDir(site_home, collection_name) +
	    File.separatorChar+"building";
    }
    /** collection building directory path */	 
    static public String collectionImportDir(String site_home,
					   String collection_name) {
	return collectionBaseDir(site_home, collection_name) +
	    File.separatorChar+"import";
    }
    /** collection building directory path */	 
    static public String collectionIndexDir(String site_home,
					   String collection_name) {
	return collectionBaseDir(site_home, collection_name) +
	    File.separatorChar+"index";
    }

    /** text path (for doc retrieval) relative to collectionBaseDir */
    static public String collectionTextPath(String collection_name) {
	return "index"+File.separatorChar+"text"+File.separatorChar+
	    collection_name;
    }

    /** index path (for querying) relative to collectionBaseDir */
    static public String collectionIndexPath(String collection_name,
					     String index_name) {
	return "index"+File.separatorChar+index_name+File.separatorChar+
	    collection_name;
    }

    /** absolute path for an associated file */
    static public String assocFileAbsolutePath(String site_home,
					       String collection_name,
					       String assoc_file_path,
					       String filename) {
	return collectionBaseDir(site_home, collection_name)+
	    File.separatorChar+"index"+File.separatorChar+
	    "assoc"+File.separatorChar+assoc_file_path+
	    File.separatorChar+filename;
    }

    static public String siteHome(String gsdl3_home, String site_name) {
	return gsdl3_home + File.separatorChar + "web" +
	    File.separatorChar + "sites" + 
	    File.separatorChar +site_name;
    }

    static public String interfaceHome(String gsdl3_home, 
				       String interface_name) {
	return gsdl3_home + File.separatorChar + "web" +
	    File.separatorChar + "interfaces" + 
	    File.separatorChar + interface_name;
    }
    
    static public String siteStylesheetFile(String site_home,
					    String filename) {
	return site_home+File.separatorChar + "transform" +
	    File.separatorChar + filename;
    }
	
	
    /** returns the absolute path to a stylesheet 
     * stylesheets are looked for in the following order
     * collect-specific, 
     * site-specific, interface-specific, default
     * returns null  if the file cannot be found 
     *
     * this is not so good because sites may be on a different computer */
    static public String stylesheetFile(String gsdl3_home,
					String site_name,
					String interface_name,
					String collection,
					String filename) {

	String site_home = siteHome(gsdl3_home, site_name);
	// try collection first
	File stylesheet = null;
	if (!collection.equals("")) {
	    
	    String coll_home = collectionBaseDir(site_home, collection);
	    stylesheet = new File(coll_home +File.separatorChar+
				  "transform"+File.separatorChar+filename);
	    if (stylesheet.exists()) {
		return stylesheet.getPath();
	    }
	}
	// try site one next
	
	stylesheet = new File(site_home +File.separatorChar+
				   "transform"+File.separatorChar+filename);
	if (stylesheet.exists()) {
	    return stylesheet.getPath();
	}
	// try current interface
	String interface_home = interfaceHome(gsdl3_home, 
					      interface_name);
	stylesheet = new File(interface_home+File.separatorChar+
			      "transform"+File.separatorChar+filename);
	if (stylesheet.exists()) {
	    return stylesheet.getPath();
	}
	// try default interface
	interface_home = interfaceHome(gsdl3_home, "default");
	stylesheet = new File(interface_home+File.separatorChar+
			      "transform"+File.separatorChar+filename);
	if (stylesheet.exists()) {
	    return stylesheet.getPath();
	}
	    
	// cant find it
	return null;
    }

    /** returns the path to the stylesheet used to transform config file
     * format statements*/
    public static String configFileFormatStylesheet() {
	URL url = ClassLoader.getSystemResource("config_format.xsl");
	if (url == null) {
	    return "";
	}
	return url.getFile();
    }

    /** base directory for phind data */
    public static String phindBaseDir(String site_home, String coll_name,
				      String phind_index) {
	return site_home + File.separatorChar +
	    "collect" + File.separatorChar +
	    coll_name + File.separatorChar +
	    "index" + File.separatorChar +
	    "phind"+phind_index;
    }

    /** the gdbm database file - 
     * note, need to change extension depending on OS */
    static public String GDBMDatabaseFile(String site_home, 
					  String collection_name) {

	return site_home + File.separatorChar +
	    "collect" + File.separatorChar +
	    collection_name + File.separatorChar +
	    "index" + File.separatorChar + "text" + File.separatorChar +
	    collection_name + ".ldb";

    }

    // some file utility methods

    /** read in a file and encode it using base64
     * encoded data returned as a String */
    static public String base64EncodeFromFile(String in_filename) {
	byte [] data=null;
	try {
	    data = readFile(in_filename);
	} catch (Exception e) {
	    System.err.println("GSFile.base64EncodeFromFile: couldn't read the file");
	}
	String encodedString = Base64.encode(data);
	return encodedString;

    }

    /** decode some base64 data, and write it to the specified file */
    static public boolean base64DecodeToFile(String data, String out_filename) {
	try {
	    byte[] buffer=Base64.decode(data);
	    writeFile(buffer, out_filename);
	   
	} catch (Exception e) {
	    System.err.println("GSFile.base64DecodeToFile: file opening/closing errors"+e.getMessage());
	    return false;
	}
	return true;
	
    }

    /** read in a file to a byte array */
    public static byte[] readFile(String filename) throws IOException {
	File file = new File(filename);
	BufferedInputStream bis = new BufferedInputStream(new
	    FileInputStream(file));
	int bytes = (int) file.length();
	byte[] buffer = new byte[bytes];
	int readBytes = bis.read(buffer);
	bis.close();
	return buffer;
    }

    /** write a byte array to a file */
    public static void writeFile(byte [] buffer, String filename) throws IOException {
	File file = new File(filename);
	BufferedOutputStream bos = new BufferedOutputStream(new
	    FileOutputStream(file));
	bos.write(buffer);
	bos.close();
    }

    public static boolean deleteFile(File f) {

	if (f.isDirectory()) {
	    File[] files = f.listFiles();
	    for (int i=0; files!=null && i<files.length; i++) {
		deleteFile(files[i]);
	    }

	}
	// delete the file or directory
	return f.delete();
    }
    
    /** Recursively moves the contents of source file to destination,
     * maintaining paths.
     * @param source A File representing the directory whose contents you
     * wish to move.
     * @param destination A File representing the directory you wish to move
     * files to.
     * @return true if successful
     */
    public static boolean moveDirectory(File source, File destination) {

	// first try rename
	if (source.renameTo(destination)) {
	    return true;
	}

	// john T. said that this sometimes doesn't work, so you have to copy files manually

	// copied from gatherer Utility class
	File input[] = source.listFiles();
	for(int i = 0; i < input.length; i++) {
	    File output = new File(destination, input[i].getName());
	    if (input[i].isDirectory()) {
		moveDirectory(input[i], output);
	    } else {
		// Copy the file
		try {
		    output.getParentFile().mkdirs();
		    FileInputStream in = new FileInputStream(input[i]);
		    FileOutputStream out = new FileOutputStream(output);
		    int value = 0;
		    while((value = in.read()) != -1) {
			out.write(value);
		    }
		    in.close();
		    out.close();
		    // Delete file
		    input[i].delete();
		} catch (Exception e) {
		    System.err.println("GSFile.moveDirectory: exception: "+e.getMessage());
		    return false;
		}
		
	    }
	}
	return true;
    }
   
}