/*
 *    Dictionary.java
 *    Copyright (C) 2005 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.util.ResourceBundle;
import java.util.Locale;
import java.util.Enumeration;

import org.apache.log4j.*;

public class Dictionary {

    static Logger logger = Logger.getLogger(org.greenstone.gsdl3.util.Dictionary.class.getName());

    /** The locale of this dictionary. */
    protected Locale locale = null;
    
    /** The resource that has been loaded */
    protected String resource = null;

    /** The ResourceBundle which contains the raw key-value mappings. Loaded from a file named "resource_locale.properties*/
    private ResourceBundle raw = null;

    /**  Constructs the Dictionary class by first creating a locale from the specified language, (or using the default locale if this didn't work), then loading a resource bundle based on this locale. 
     */
    public Dictionary(String resource, String lang) {
	// Initialize.
	
	this.locale = new Locale(lang);
	this.resource = resource;
	if (this.locale == null) {
	    this.locale = Locale.getDefault();
	}
	try {
	    this.raw = ResourceBundle.getBundle(this.resource, this.locale);
	} catch (Exception e) {
	    //logger.debug("Dictionary: couldn't locate a resource bundle for "+resource);
	}
    }

    public Dictionary(String resource, Locale locale) {
	this.locale = locale;
	this.resource = resource;
	try {
	    this.raw = ResourceBundle.getBundle(this.resource, this.locale);
	} catch (Exception e) {
	    //logger.debug("Dictionary: couldn't locate a resource bundle for "+resource);
	}
    }

    /**  Constructs the Dictionary class by first creating a locale from the specified language, (or using the default locale if this didn't work), then loading a resource bundle based on this locale. A classloader is specified which can be used to find the resource.
     */
    public Dictionary(String resource, String lang, ClassLoader loader) {
	// Initialize.
	
	this.locale = new Locale(lang);
	this.resource = resource;
	if (this.locale == null) {
	    this.locale = Locale.getDefault();
	}
	// try the specified class loader
	try {
	    this.raw = ResourceBundle.getBundle(this.resource, this.locale, loader);
	    return;
	} catch (Exception e) {};
	
	try {
	    this.raw = ResourceBundle.getBundle(this.resource, this.locale);
	} catch (Exception ex) {
	    //logger.debug("Dictionary: couldn't locate a resource bundle for "+resource);
	}
	
    }

    
    public Enumeration getKeys() {
	if (this.raw != null) {
	    return this.raw.getKeys();
	}
	return null;
    }
    /** Overloaded to call get with both a key and an empty argument array.
     * @param key A <strong>String</strong> which is mapped to a initial String within the ResourceBundle.
     * @return A <strong>String</strong> which has been referenced by the key String and that  contains no argument fields.
     */
    public String get(String key) {
	return get(key, null);
    }
    
    /** Used to retrieve a property value from the Locale specific ResourceBundle, based upon the key and arguments supplied. If the key cannot be found or if some other part of the call fails a default (English) error message is returned. <BR>
     * Here the get recieves a second argument which is an array of Strings used to populate argument fields, denoted {<I>n</I>}, within the value String returned.
     * @param key A <strong>String</strong> which is mapped to a initial String within the ResourceBundle.
     * @param args A <strong>String[]</strong> used to populate argument fields within the complete String.
     * @return A <strong>String</strong> which has been referenced by the key String and that either contains no argument fields, or has had the argument fields  populated  with argument Strings provided in the get call.
     */
    public String get(String key, String args[]) {
	if (this.raw == null) {
	    return null;
	}
	try {
	    String initial_raw = this.raw.getString(key);
	    // convert to unicode, copied from gatherer dictionary
	    String initial = new String(initial_raw.getBytes("ISO-8859-1"), "UTF-8");

	    // Remove any comments from the string
	    if (initial.indexOf("#") != -1) {
		initial = initial.substring(0, initial.indexOf("#"));
	    }
	    // If the string contains arguments we have to insert them.
	    StringBuffer complete = new StringBuffer();
	    // While we still have initial string left.
	    while(initial.length() > 0 && initial.indexOf('{') != -1 && initial.indexOf('}') != -1) {
		// Remove preamble
		int opening = initial.indexOf('{');
		int closing = initial.indexOf('}');
		int comment_mark = initial.indexOf('-', opening); // May not exist
		if (comment_mark > closing) { // May also be detecting a later comment
		    comment_mark = -1;
		}
		complete.append(initial.substring(0, opening));
		
		// Parse arg_num
		String arg_str = null;
		if (comment_mark != -1) {
		  arg_str = initial.substring(opening + 1, comment_mark);
		} else {
		  arg_str = initial.substring(opening + 1, closing);
		}
		if(closing + 1 < initial.length()) {
		    initial = initial.substring(closing + 1);
		}
		else {
		    initial = "";
		}
		int arg_num = Integer.parseInt(arg_str);
		// Insert argument
		if(args != null && 0 <= arg_num && arg_num < args.length) {
		  complete.append(args[arg_num]);
		}
	    }
	    complete.append(initial);
	    return complete.toString();
	}
	catch (Exception e) {
	    //logger.debug("Dictionary Error: couldn't find string for key:" + key +" in resource "+this.resource);
	    return null;
	}
    }
}