/*
* MIT License
*
* Copyright (c) 2017 Inova IT
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package si.inova.neatle.operation;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCharacteristic;
import android.support.annotation.RestrictTo;
import java.nio.charset.Charset;
import java.util.UUID;
/**
* A result of a single command.
*/
public class CommandResult {
/**
* Characteristic value format type uint8
*/
public static final int FORMAT_UINT8 = 0x11;
/**
* Characteristic value format type uint16
*/
public static final int FORMAT_UINT16 = 0x12;
/**
* Characteristic value format type uint32
*/
public static final int FORMAT_UINT32 = 0x14;
/**
* Characteristic value format type sint8
*/
public static final int FORMAT_SINT8 = 0x21;
/**
* Characteristic value format type sint16
*/
public static final int FORMAT_SINT16 = 0x22;
/**
* Characteristic value format type sint32
*/
public static final int FORMAT_SINT32 = 0x24;
private final UUID uuid;
private final byte[] data;
private final int status;
private final long timestamp;
CommandResult(UUID uuid, byte[] data, int status, long timestamp) {
this.uuid = uuid;
this.data = data;
this.status = status;
this.timestamp = timestamp;
}
/**
* Returns the raw response of a command, in bytes.
*
* @return the response in bytes
*/
public byte[] getValue() {
return data;
}
/**
* Returns the string representation of the command response (in UTF8 encoding). If the data
* received is not a string, it throws an {@link IllegalStateException}.
*
* @return the string representation of the command response.
* @throws IllegalStateException if the command data is not a UTF8 string
*/
public String getValueAsString() {
if (data == null) {
return null;
} else if (data.length == 0) {
return "";
} else {
return new String(data, Charset.forName("UTF8"));
}
}
/**
* Returns the value of the command result represented as an int32 (int). It will thro a
* {@link java.nio.BufferUnderflowException} if the data has less than 4 bytes (e.g. is not an int).
*
* @return the value of the data as an int.
*/
public int getValueAsInt() {
if (data.length > 4) {
throw new IllegalStateException("Data has more than 4 bytes and cannot be converted to an integer");
}
int ret = 0;
switch (data.length) {
case 4:
ret |= (data[3] & 0xFF) << ((data.length - 4) * 8);
case 3:
ret |= (data[2] & 0xFF) << ((data.length - 3) * 8);
case 2:
ret |= (data[1] & 0xFF) << ((data.length - 2) * 8);
case 1:
ret |= (data[0] & 0xFF) << ((data.length - 1) * 8);
}
return ret;
}
/**
* Return the stored value of this characteristic.
*
* <p>The formatType parameter determines how the characteristic value
* is to be interpreted. For example, settting formatType to
* {@link BluetoothGattCharacteristic#FORMAT_UINT16} specifies that the first two bytes of the
* characteristic value at the given offset are interpreted to generate the
* return value.
*
* @param formatType The format type used to interpret the characteristic
* value.
* @param offset Offset at which the integer value can be found.
* @return Cached value of the characteristic or null of offset exceeds
* value size.
*/
public Integer getFormattedIntValue(int formatType, int offset) {
if ((offset + formatType & 0xF) > data.length) return null;
switch (formatType) {
case FORMAT_UINT8:
return unsignedByteToInt(data[offset]);
case FORMAT_UINT16:
return unsignedBytesToInt(data[offset], data[offset + 1]);
case FORMAT_UINT32:
return unsignedBytesToInt(data[offset], data[offset + 1],
data[offset + 2], data[offset + 3]);
case FORMAT_SINT8:
return unsignedToSigned(unsignedByteToInt(data[offset]), 8);
case FORMAT_SINT16:
return unsignedToSigned(unsignedBytesToInt(data[offset],
data[offset + 1]), 16);
case FORMAT_SINT32:
return unsignedToSigned(unsignedBytesToInt(data[offset],
data[offset + 1], data[offset + 2], data[offset + 3]), 32);
}
return null;
}
/**
* Returns the UUID of the characteristic this data was read from.
*
* @return the uuid
*/
public UUID getUUID() {
return uuid;
}
/**
* Returns the status of the command execution. For instance, {@link BluetoothGatt#GATT_SUCCESS}
* if the command was successful.
*
* @return the status of the command execution.
*/
public int getStatus() {
return status;
}
/**
* Returns the timestamp of this command.
*
* @return the timestamp
*/
public long getTimestamp() {
return timestamp;
}
/**
* Checks if this command was successful.
*
* @return true if the command was succesful, false otherwise
*/
public boolean wasSuccessful() {
return status == BluetoothGatt.GATT_SUCCESS;
}
/**
* Convert signed bytes to a 16-bit unsigned int.
*/
private int unsignedBytesToInt(byte b0, byte b1) {
return (unsignedByteToInt(b0) + (unsignedByteToInt(b1) << 8));
}
/**
* Convert a signed byte to an unsigned int.
*/
private int unsignedByteToInt(byte b) {
return b & 0xFF;
}
/**
* Convert an unsigned integer value to a two's-complement encoded
* signed value.
*/
private int unsignedToSigned(int unsigned, int size) {
if ((unsigned & (1 << size - 1)) != 0) {
unsigned = -1 * ((1 << size - 1) - (unsigned & ((1 << size - 1) - 1)));
}
return unsigned;
}
/**
* Convert signed bytes to a 32-bit unsigned int.
*/
private int unsignedBytesToInt(byte b0, byte b1, byte b2, byte b3) {
return (unsignedByteToInt(b0) + (unsignedByteToInt(b1) << 8))
+ (unsignedByteToInt(b2) << 16) + (unsignedByteToInt(b3) << 24);
}
@Override
public String toString() {
return "CommandResult[status: " + status + ", uuid:" + uuid + ", data:" + (data == null ? "null" : data.length) + "]";
}
@RestrictTo(RestrictTo.Scope.LIBRARY)
public static CommandResult createCharacteristicRead(BluetoothGattCharacteristic characteristic, int status) {
long when = System.currentTimeMillis();
return new CommandResult(characteristic.getUuid(), characteristic.getValue(), status, when);
}
@RestrictTo(RestrictTo.Scope.LIBRARY)
public static CommandResult createErrorResult(UUID characteristicUUID, int error) {
long when = System.currentTimeMillis();
return new CommandResult(characteristicUUID, null, error, when);
}
@RestrictTo(RestrictTo.Scope.LIBRARY)
public static CommandResult createEmptySuccess(UUID characteristicUUID) {
long when = System.currentTimeMillis();
return new CommandResult(characteristicUUID, null, BluetoothGatt.GATT_SUCCESS, when);
}
@RestrictTo(RestrictTo.Scope.LIBRARY)
public static CommandResult createCharacteristicChanged(BluetoothGattCharacteristic characteristic) {
long when = System.currentTimeMillis();
return new CommandResult(characteristic.getUuid(), characteristic.getValue(), BluetoothGatt.GATT_SUCCESS, when);
}
}
