package twinfeats.pilot.pdb;



import java.io.*;

import java.util.*;



/**

 * Class for reading and writing USRobotics/3Com Pilot and IBM WorkPad .pdb

 * files.

 * @version     1.0 Dec 17 1997

 * @author      Kent L. Smotherman

 */

public class PDB {

    public PDB() {

    }



    /**

     * Read and parse a PDB file

     * @param filename      Name of PDB file to read

     * exception Exception  For any exception during the read process

     */

    public void readPDB(String filename) throws Exception {

        FileInputStream fis=null;

        DataInputStream dis=null;

        String s;

        byte[] b = new byte[32];

        int i,l;

        short n;

        File f=null;



        try {

            f = new File(filename);

            fis = new FileInputStream(f);

            dis = new DataInputStream(fis);

            dis.read(b,0,32);

            mName = new String(b,0);

            mFlags = dis.readShort();

            mVersion = dis.readShort();

            dis.readInt();

            dis.readInt();

            dis.readInt();

            mModNum = dis.readInt();

            dis.readInt();

            dis.readInt();

            dis.read(b,0,4);

            mType = new String(b,0,0,4);

            dis.read(b,0,4);

            mCreator = new String(b,0,0,4);

            dis.readInt();

            dis.readInt();

            n = dis.readShort();

            mRecords = new Vector((int)n);

            mHdrs = new RecordHdr[n];

            for (i=0;i<n;i++) {

                mHdrs[i] = new RecordHdr(dis.readInt(),dis.readInt());

            }

            dis.readShort();

            for (i=0;i<n;i++) {

                if (i < n-1)    //not last record

                    l = mHdrs[i+1].mOffset-mHdrs[i].mOffset;

                else

                    l = (int)f.length()-mHdrs[i].mOffset;

                b = new byte[l];

                dis.read(b,0,l);

                mRecords.addElement(new PDBRecord(mHdrs[i].mID,b,false));

            }

        }

        catch (Exception e1) {

            System.out.println("Error opening "+filename);

            throw e1;

        }

        finally {

            try {

                if (fis != null)

                    fis.close();

            }

            catch (Exception e2) {

            }

        }

    }



    /**

     * Write a PDB file to disk

     * @param filename      Name of PDB file to write

     * exception Exception  For any exception during the write process

     */

    public void writePDB(String filename) throws Exception {

        FileOutputStream fos=null;

        DataOutputStream dos=null;

        PDBRecord record;

        int offset;



        try {

            fos = new FileOutputStream(filename);

            dos = new DataOutputStream(fos);

        }

        catch (Exception e1) {

            String s = "Error opening "+filename;

            System.out.println(s);

            throw e1;

        }

        try {

            dos.writeBytes(fillField(mName,32,(char)0));

            dos.writeShort(mFlags);

            dos.writeShort(mVersion);

            int t = (int)((new Date()).getTime()/1000)+2082844800;

            dos.writeInt(t);

            dos.writeInt(t);

            dos.writeInt(0);

            dos.writeInt(mModNum);

            dos.writeInt(0);

            dos.writeInt(0);

            dos.writeBytes(fillField(mType,4,(char)0));

            dos.writeBytes(fillField(mCreator,4,(char)0));

            dos.writeInt(0);

            dos.writeInt(0);

            dos.writeShort((short)mRecords.size());

            offset =80+mRecords.size()*8;

            for (int i=0;i<mRecords.size();i++) {

                record = (PDBRecord)mRecords.elementAt(i);

                dos.writeInt(offset);

                dos.writeInt(record.getID());

                offset += record.getLength();

            }

            dos.writeShort(0);

            for (int i=0;i<mRecords.size();i++) {

                record = (PDBRecord)mRecords.elementAt(i);

                dos.write(record.getData(),0,record.getLength());

            }

        }

        catch (Exception e2) {

            System.out.println("Error writing to "+filename);

            throw e2;

        }

        finally {

            dos.close();

        }

    }



    /**

     * Utility function to pad a field on the left to a fixed length

     * @param data      The field data

     * @param length    The fixed field length

     * @param c         The character to left-pad the data

     */

    public static String fillField(String data, int length, char c) {

        if (data.length() > length)

            return data.substring(0,length);

        for (int i=data.length();i<length;i++)

            data += c;

        return data;

    }



    /**

     * Utility function to make a 16 bit integer into a 2 byte String

     * @param data      16 bit integer

     * @returns         String

     */

     public static String makeString(int data) {

        byte[] b = new byte[2];

        b[0] = (byte)(data>>8);

        b[1] = (byte)(data&0xff);

        return new String(b);

     }

     

    /**

     * Retrieve the name of the PDB file that was read

     * @returns         Name of PDB file read

     */

    public String getName() {

        return mName;

    }

    

    /**

     * Retrieve the PDB header flags

     * @returns          header flags

     */

    public short getFlags() {

        return mFlags;

    }

    

    /**

     * Retrieve the PDB version

     * @returns          version

     */

    public short getVersion () {

        return mVersion;

    }

    

    /**

     * Retrieve the PDB modification number

     * @returns         modification number

     */

    public int getModNum() {

        return mModNum;

    }

    

    /**

     * Retrieve the PDB type

     * @returns         type

     */

    public String getType() {

        return mType;

    }

    

    /**

     * Retrieve the PDB creator

     * @returns         creator

     */

    public String getCreator() {

        return mCreator;

    }

    

    /**

     * Retrieve vector of all PDB records

     * @returns         Vector of PDBRecord's

     */

    public Vector getRecords() {

        return mRecords;

    }

    

    String  mName;

    short   mFlags;

    short   mVersion;

    int     mModNum;

    String  mType;

    String  mCreator;

    public Vector  mRecords;



    RecordHdr[] mHdrs;

}



class RecordHdr {

    public RecordHdr(int offset, int id) {

        UpdateRecordHdr(offset,id);

    }



    public void UpdateRecordHdr(int offset,int id) {

        mOffset = offset;

        mID = id;

    }



    int mOffset;

    int mID;

}