/**
* Copyright (c) 2010-2013, openHAB.org and others.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*/
package org.openhab.binding.insteonplm.internal.message;
import org.openhab.binding.insteonplm.internal.device.InsteonAddress;
import org.openhab.binding.insteonplm.internal.utils.Utils;
/**
* An Insteon message has several fields with known type and offset
* within the message. This class represents a single field, and
* holds name, type, and offset (but not value!).
*
* @author Daniel Pfrommer
* @since 1.5.0
*/
public final class Field {
private final String m_name;
private final int m_offset;
private final DataType m_type;
public String getName() { return m_name; }
public int getOffset() { return m_offset; }
public DataType getType() { return m_type; }
public Field(String name, DataType type, int off) {
m_name = name;
m_type = type;
m_offset = off;
}
private void check(int arrayLen, DataType t) throws FieldException {
checkSpace(arrayLen);
checkType(t);
}
private void checkSpace(int arrayLen) throws FieldException {
if (m_offset + m_type.getSize() > arrayLen) {
throw new FieldException("field write beyond end of msg");
}
}
private void checkType(DataType t) throws FieldException {
if (m_type != t) {
throw new FieldException("field write type mismatch!");
}
}
public String toString() {
return getName() + " Type: " + getType() + " Offset " + getOffset();
}
public String toString(byte[] array) {
String s = m_name + ":";
try {
switch (m_type) {
case BYTE: s += Utils.getHexByte(getByte(array)); break;
case INT: s += Integer.toString(getInt(array)); break;
case ADDRESS: s += getAddress(array).toString(); break;
default: break;
}
} catch (FieldException e) {
// will just return empty string
}
return s;
}
public void set(byte[] array, Object o) throws FieldException {
switch(getType()) {
case BYTE: setByte(array, (Byte) o); break;
case INT: setInt(array, (Integer) o); break;
//case FLOAT: setFloat(array, (float) o); break;
case ADDRESS: setAddress(array, (InsteonAddress) o); break;
default : throw new FieldException("Not implemented data type " + getType() + "!");
}
}
/**
* Writes a byte value to a byte array, at the proper offset.
* Use this function to set the value of a field within a message.
* @param array the destination array
* @param b the value you want to set the byte to
* @throws FieldException
*/
public void setByte(byte[] array, byte b) throws FieldException {
check(array.length, DataType.BYTE);
array[m_offset] = b;
}
/**
* Writes the value of an integer field to a byte array
* Use this function to set the value of a field within a message.
* @param array the destination array
* @param i the integer value to set
*/
public void setInt(byte[] array, int i) throws FieldException {
check(array.length, DataType.INT);
array[m_offset] = (byte) ((i >>> 24) & 0xFF);
array[m_offset + 1] = (byte) ((i >>> 16) & 0xFF);
array[m_offset + 2] = (byte) ((i >>> 8) & 0xFF);
array[m_offset + 3] = (byte) ((i >>> 0) & 0xFF);
}
/**
* Writes the value of an InsteonAddress to a message array.
* Use this function to set the value of a field within a message.
* @param array the destination array
* @param adr the insteon address value to set
*/
public void setAddress(byte[] array, InsteonAddress adr) throws FieldException {
check(array.length, DataType.ADDRESS);
adr.storeBytes(array, m_offset);
}
/**
* Fetch a byte from the array at the field position
* @param array the array to fetch from
* @return the byte value of the field
*/
public byte getByte(byte[] array) throws FieldException {
check(array.length, DataType.BYTE);
return array[m_offset];
}
/**
* Fetch an int from the array at the field position
* @param array the array to fetch from
* @return the int value of the field
*/
public int getInt(byte[] array) throws FieldException {
check(array.length, DataType.INT);
byte b1 = array[m_offset];
byte b2 = array[m_offset + 1];
byte b3 = array[m_offset + 2];
byte b4 = array[m_offset + 3];
int value = ((b1 << 24) + (b2 << 16) + (b3 << 8) + (b4 << 0));
return value;
}
/**
* Fetch an insteon address from the field position
* @param array the array to fetch from
* @return the address
*/
public InsteonAddress getAddress(byte[] array) throws FieldException {
check(array.length, DataType.ADDRESS);
InsteonAddress adr = new InsteonAddress();
adr.loadBytes(array, m_offset);
return adr; }
/**
* Equals test
*/
@Override
public boolean equals(Object o) {
if (o instanceof Field) {
Field f = (Field) o;
return (f.getName().equals(getName())) && (f.getOffset() == getOffset());
} else {
return false;
}
}
}