prestonbane/src/engine/net/ByteBufferReader.java

// • ▌ ▄ ·.  ▄▄▄·  ▄▄ • ▪   ▄▄· ▄▄▄▄·  ▄▄▄·  ▐▄▄▄  ▄▄▄ .
// ·██ ▐███▪▐█ ▀█ ▐█ ▀ ▪██ ▐█ ▌▪▐█ ▀█▪▐█ ▀█ •█▌ ▐█▐▌·
// ▐█ ▌▐▌▐█·▄█▀▀█ ▄█ ▀█▄▐█·██ ▄▄▐█▀▀█▄▄█▀▀█ ▐█▐ ▐▌▐▀▀▀
// ██ ██▌▐█▌▐█ ▪▐▌▐█▄▪▐█▐█▌▐███▌██▄▪▐█▐█ ▪▐▌██▐ █▌▐█▄▄▌
// ▀▀  █▪▀▀▀ ▀  ▀ ·▀▀▀▀ ▀▀▀·▀▀▀ ·▀▀▀▀  ▀  ▀ ▀▀  █▪ ▀▀▀
//      Magicbane Emulator Project © 2013 - 2022
//                www.magicbane.com


package engine.net;

import engine.math.Vector3f;
import engine.math.Vector3fImmutable;
import engine.util.ByteBufferUtils;
import engine.util.ByteUtils;

import java.nio.Buffer;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.util.UUID;

public class ByteBufferReader {

    private final ByteBuffer bb;
    private final boolean endianFlip;

    /**
     * Helper class for getting structured information out of a ByteBuffer
     * easily. ByteBuffer passed in is copied to an internal ByteBuffer.
     * <B>bbin</B> must have the position attribute at the <i>end</i> of the
     * data to be copied over, since <b>bbin.flip()</b> is called in this
     * constructor.
     *
     * @param bbin
     * @param endianFlip
     */
    public ByteBufferReader(ByteBuffer bbin, boolean endianFlip) {
        super();

        // Copy supplied BB.
        this.bb = ByteBuffer.allocate(bbin.position()); //FIXME Do we want to get this from pool?
        bbin.flip();
        this.bb.put(bbin);

        // prepare bb for reading
        this.bb.flip();

        this.endianFlip = endianFlip;
    }

    /*
     * Getters
     */

    /**
     * @return
     * @see java.nio.ByteBuffer#get()
     */
    public byte get() {
        return bb.get();
    }

    public void get(byte[] ba) {
        this.bb.get(ba);
    }

    /**
     * @return
     * @see java.nio.ByteBuffer#getChar()
     */
    public char getChar() {
        char x = bb.getChar();
        if (this.endianFlip) {
            x = Character.reverseBytes(x);
        }
        return x;
    }

    /**
     * @return
     * @see java.nio.ByteBuffer#getDouble()
     */
    public double getDouble() {
        double x = 0;
        if (this.endianFlip) {
            x = bb.order(ByteOrder.LITTLE_ENDIAN).getDouble();
            bb.order(ByteOrder.BIG_ENDIAN);
        } else {
            x = bb.getDouble();
        }
        return x;
    }

    /**
     * @return
     * @see java.nio.ByteBuffer#getFloat()
     */
    public float getFloat() {
        float x = 0;
        if (this.endianFlip) {
            x = bb.order(ByteOrder.LITTLE_ENDIAN).getFloat();
            bb.order(ByteOrder.BIG_ENDIAN);
        } else {
            x = bb.getFloat();
        }
        return x;
    }

    /**
     * @return
     * @see java.nio.ByteBuffer#getInt()
     */
    public int getInt() {
        int x = bb.getInt();
        if (this.endianFlip) {
            x = Integer.reverseBytes(x);
        }
        return x;
    }

    /**
     * @return
     * @see java.nio.ByteBuffer#getLong()
     */
    public long getLong() {
        long x = bb.getLong();
        if (this.endianFlip) {
            x = Long.reverseBytes(x);
        }
        return x;
    }

    /**
     * @return
     * @see java.nio.ByteBuffer#getShort()
     */
    public short getShort() {
        short x = bb.getShort();
        if (this.endianFlip) {
            x = Short.reverseBytes(x);
        }
        return x;
    }

    public final String getString() {
        if (this.endianFlip) {
            return ByteBufferUtils.getString(this.bb, true, false);
        } else {
            return ByteBufferUtils.getString(this.bb, false, false);
        }
    }

    public final String getSmallString() {
        if (this.endianFlip) {
            return ByteBufferUtils.getString(this.bb, true, true);
        } else {
            return ByteBufferUtils.getString(this.bb, false, true);
        }
    }

    public final String getHexString() {
        if (this.endianFlip) {
            return ByteBufferUtils.getHexString(this.bb, true);
        } else {
            return ByteBufferUtils.getHexString(this.bb);
        }
    }

    public final String getUnicodeString() {
        if (this.endianFlip) {
            return ByteBufferUtils.getUnicodeString(this.bb, true);
        } else {
            return ByteBufferUtils.getUnicodeString(this.bb);
        }
    }

    public String get1ByteAsHexString() {
        return getBytesAsHexStringCommon(new byte[1]);
    }

    public String get2BytesAsHexString() {
        return getBytesAsHexStringCommon(new byte[2]);
    }

    public String get4BytesAsHexString() {
        return getBytesAsHexStringCommon(new byte[4]);
    }

    public String get8BytesAsHexString() {
        return getBytesAsHexStringCommon(new byte[8]);
    }

    private String getBytesAsHexStringCommon(byte[] ba) {
        this.bb.get(ba);
        if (this.endianFlip) {
            return ByteUtils.byteArrayToStringHex(ByteUtils
                    .switchByteArrayEndianness(ba));
        } else {
            return ByteUtils.byteArrayToStringHex(ba);
        }
    }

    public Vector3f getVector3f() {
        Vector3f out = new Vector3f();
        if (this.endianFlip) {
            out.x = Float
                    .intBitsToFloat(Integer.reverseBytes(this.bb.getInt()));
            out.y = Float
                    .intBitsToFloat(Integer.reverseBytes(this.bb.getInt()));
            out.z = Float
                    .intBitsToFloat(Integer.reverseBytes(this.bb.getInt()));
        } else {
            out.x = this.bb.getFloat();
            out.y = this.bb.getFloat();
            out.z = this.bb.getFloat();
        }
        return out;
    }

    public Vector3fImmutable getVector3fImmutable() {
        Vector3fImmutable out;
        if (this.endianFlip) {
            out = new Vector3fImmutable(Float.intBitsToFloat(Integer
                    .reverseBytes(this.bb.getInt())), Float
                    .intBitsToFloat(Integer.reverseBytes(this.bb.getInt())),
                    Float
                            .intBitsToFloat(Integer.reverseBytes(this.bb
                                    .getInt())));
        } else {
            out = new Vector3fImmutable(this.bb.getFloat(), this.bb.getFloat(),
                    this.bb.getFloat());
        }
        return out;
    }

    public final UUID getUUID() {
        final byte[] buffer = new byte[16];
        this.bb.get(buffer);

        long msb = 0;
        long lsb = 0;

        for (int i = 0; i < 8; i++) {
            msb = (msb << 8) | (buffer[i] & 0xff);
        }

        for (int i = 8; i < 16; i++) {
            lsb = (lsb << 8) | (buffer[i] & 0xff);
        }

        return new UUID(msb, lsb);
    }


    /*
     * Monitors
     */

    public byte monitorByte(byte expectedValue, String label) {
        return this.monitorByte(expectedValue, label, false);
    }

    public byte monitorByte(byte expectedValue, String label, boolean peek) {
        //		if (x != expectedValue) {
//			Logger.info("MonitorTrip: " + label + ". Expected: "
//					+ expectedValue + " Got: " + x);
//		}
        return this.get();
    }

    public short monitorShort(short expectedValue, String label) {
        return this.monitorShort(expectedValue, label, false);
    }

    public short monitorShort(short expectedValue, String label, boolean peek) {
        //		if (x != expectedValue) {
//			Logger.info("MonitorTrip: " + label + ". Expected: "
//					+ expectedValue + " Got: " + x);
//		}
        return this.getShort();
    }

    public int monitorInt(int expectedValue, String label) {
        return this.monitorInt(expectedValue, label, false);
    }

    public int monitorInt(int expectedValue, String label, boolean peek) {
        //		if (x != expectedValue) {
//			Logger.info("MonitorTrip: " + label + ". Expected: "
//					+ expectedValue + " Got: " + x);
//		}
        return this.getInt();
    }

    public long monitorLong(long expectedValue, String label) {
        return this.monitorLong(expectedValue, label, false);
    }

    public long monitorLong(long expectedValue, String label, boolean peek) {
        //		if (x != expectedValue) {
//			Logger.info("MonitorTrip: " + label + ". Expected: "
//					+ expectedValue + " Got: " + x);
//		}
        return this.getLong();
    }

    /*
     * ByteBuffer delegates
     */

    /**
     * @return
     * @see java.nio.Buffer#hasRemaining()
     */
    public final boolean hasRemaining() {
        return bb.hasRemaining();
    }

    /**
     * @return
     * @see java.nio.Buffer#limit()
     */
    public final int limit() {
        return bb.limit();
    }

    /**
     * @return
     * @see java.nio.Buffer#position()
     */
    public final int position() {
        return bb.position();
    }

    public final Buffer position(int newPosition) {
        return bb.position(newPosition);
    }

    /**
     * @return
     * @see java.nio.Buffer#remaining()
     */
    public final int remaining() {
        return bb.remaining();
    }

    /*
     * Status getters
     */

    protected ByteBuffer getBb() {
        return bb;
    }

    protected boolean isEndianFlip() {
        return endianFlip;
    }

    public String getByteArray() {
        String ret = "";
        if (this.bb == null)
            return ret;
        byte[] bbyte = bb.array();
        if (bbyte == null)
            return ret;
        for (int i = 0; i < bbyte.length; i++) {
            ret += Integer.toString((bbyte[i] & 0xff) + 0x100, 16).substring(1).toUpperCase();
        }
        return ret;
    }

}