/*
 * File    : PCCFileSystem.java
 * Created : 20-jun-2000 10:00
 * By      : fbusquets
 *
 * JClic - Authoring and playing system for educational activities
 *
 * Copyright (C) 2000 - 2005 Francesc Busquets & Departament
 * d'Educacio de la Generalitat de Catalunya                                        
 *
 * 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 (see the LICENSE file).
 */

package edu.xtec.jclic.fileSystem;

import edu.xtec.jclic.clic3.Clic3;
import edu.xtec.util.ResourceBridge;
import java.awt.Image;
import java.awt.Toolkit;
import java.io.*;

/**
 *
 * @author Francesc Busquets (fbusquets@xtec.cat)
 * @version 13.08.08
 */

public abstract class PCCFileSystem extends FileSystem {
    
    String pccName;
    public String pccVersion;
    public String pccDescription;
    public int numFiles;
    public int baseOffset;
    PCCFileEntry[] fe;
    
    public PCCFileSystem(ResourceBridge rb) {
        super("", rb);
    }
    
    public PCCFileSystem(String rootPath, String pccFileName, ResourceBridge rb){
        super(rootPath, rb);
        pccName = getCanonicalNameOf(pccFileName);
    }
    
    public static PCCFileSystem createPCCFileSystem(String rootPath, String pccFileName, ResourceBridge rb) throws Exception {
        if(isStrUrl(rootPath))
            return new UrlPCC(rootPath, pccFileName, rb);
        else
            return new FilePCC(rootPath, pccFileName, rb);
    }
    
    @Override
    public String getFullRoot(){
        return root+pccName;
    }
    
    protected class PCCFileEntry extends Object {
        String fileName;
        long size, offset;
        public PCCFileEntry(String fName, long o, long s){
            fileName=stdFn(fName);
            size=s;
            offset=o;
        }
    }
    
    void initPCC(DataInputStream dis) throws Exception {
        if((pccVersion=extractLineFromDIS(dis))!=null && pccVersion.compareTo("PCC00")==0){
            pccDescription=extractLineFromDIS(dis);
            numFiles=extractShortInt(dis);
            baseOffset=(int)extractShortLong(dis);
            fe = new PCCFileEntry[numFiles];
            for(int i=0; i<numFiles; i++){
                //fe[i]=new PCCFileEntry(Clic3.validFileName(normalizePath(extractSzString(dis))),
                fe[i]=new PCCFileEntry(Clic3.validFileName(extractSzString(dis)),
                extractShortLong(dis),
                extractShortLong(dis)
                );                
                if(fe[i].fileName.length()==0) 
                    break;
            }
        }
    }
    
    public String getEntryInfo(int n){
        return (n<0 || n>=numFiles) ? "OUT OF INDEX!" : fe[n].toString();
    }
    
    public String getEntryName(int n){
        return (n<0 || n>=numFiles) ? "OUT OF INDEX!" : fe[n].fileName;
    }
    
    public int getEntryNum(String fName){
        int i=-1;
        String normalizedFName=stdFn(fName);
        
        if(numFiles>0){
            for(i=0; i<numFiles; i++){
                if(fe[i].fileName.equals(normalizedFName)) break;
            }
        }
        if(i==numFiles && altFileNames.get(fName)!=null){
            // not found, but found in altFileNames!
            normalizedFName=stdFn((String)altFileNames.get(fName));
            for(i=0; i<numFiles; i++){
                if(fe[i].fileName.equals(normalizedFName)) break;
            }
        }
        return (i==numFiles ? -1 : i);
    }
    
    protected abstract byte[] getBytes(int entryNum) throws IOException;
    
    @Override
    public byte[] getBytes(String fileName) throws IOException {
        int entryNum;
        if((entryNum=getEntryNum(fileName))==-1)
            return super.getBytes(fileName);
        return getBytes(entryNum);
    }
    
    @Override
    public long getFileLength(String fileName) throws IOException{
        int entryNum;
        return (entryNum=getEntryNum(fileName))==-1 
        ? super.getFileLength(fileName)
        : fe[entryNum].size;        
    }
    
    @Override
    public Image getImageFile(String fName) throws Exception {
        int entryNum;
        return (entryNum=getEntryNum(fName))==-1
        ? super.getImageFile(fName)
        : Toolkit.getDefaultToolkit().createImage(getBytes(entryNum));
    }
    
    public java.io.DataInputStream getDataInputStream(String fName) throws IOException {
        return new DataInputStream(super.getInputStream(fName));
    }
    
    public String extractLine(BufferedReader bfr) throws IOException {
        return bfr.readLine();
    }
    
    public String extractLineFromDIS(DataInputStream dis) throws IOException {
        StringBuilder str=new StringBuilder();
        boolean skipNext=false;
        while(true) {
            byte b=dis.readByte();
            if(skipNext) break;
            else if(b==0x0D)
                skipNext=true;
            else
                str.append((char)b);
        }
        return str.substring(0);
    }
    
    public String extractSzString(BufferedReader bfr) throws IOException {
        StringBuilder str=new StringBuilder();
        char b[] = new char[1];
        while(true){
            bfr.read(b, 0, 1);
            if(b[0]==0) 
                break;
            else 
                str.append(b[0]);
        }
        return str.substring(0);
    }
    
    public String extractSzString(DataInputStream dis) throws IOException {
        StringBuilder str=new StringBuilder();
        while(true){
            byte b=dis.readByte();
            if(b==0) 
                break;
            else 
                str.append((char)b);
        }
        return str.substring(0);
    }
    
    public int extractShortInt(DataInputStream bfr) throws IOException {
        int bt=bfr.readUnsignedByte();
        int r=bt;
        bt=bfr.readUnsignedByte();
        r+=(bt<<8);
        return r;
    }
    
    public long extractShortLong(DataInputStream bfr) throws IOException {
        long bt=bfr.readUnsignedByte();
        long r=bt;
        bt=bfr.readUnsignedByte();
        r+=(bt<<8);
        bt=bfr.readUnsignedByte();
        r+=(bt<<16);
        bt=bfr.readUnsignedByte();
        r+=(bt<<24);
        return r;
    }
    
    @Override
    public void close(){
        fe=null;
        super.close();
    }    
}