/**
 * Copyright 2017, Digi International Inc.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, you can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
package com.digi.xbee.api.packet;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Arrays;
import java.util.LinkedHashMap;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.digi.xbee.api.utils.HexUtils;

/**
 * This class represents a basic and Generic XBee packet where the payload is
 * set as a byte array without a defined structure.
 * 
 * @see XBeeAPIPacket
 */
public class GenericXBeePacket extends XBeeAPIPacket {
        
        // Constants.
        private static final int MIN_API_PAYLOAD_LENGTH = 1; // 1 (Frame type)
        
        // Variables.
        private byte[] rfData;
        
        private Logger logger;
        
        /**
         * Creates a new {@code GenericXBeePacket} from the given payload.
         * 
         * @param payload The API frame payload. It must start with the frame type 
         *                corresponding to a Generic packet ({@code 0xFF}).
         *                The byte array must be in {@code OperatingMode.API} mode.
         * 
         * @return Parsed Generic packet.
         * 
         * @throws IllegalArgumentException if {@code payload[0] != APIFrameType.GENERIC.getValue()} or
         *                                  if {@code payload.length < }{@value #MIN_API_PAYLOAD_LENGTH}.
         * @throws NullPointerException if {@code payload == null}.
         */
        public static GenericXBeePacket createPacket(byte[] payload) {
                if (payload == null)
                        throw new NullPointerException("Generic packet payload cannot be null.");
                
                // 1 (Frame type)
                if (payload.length < MIN_API_PAYLOAD_LENGTH)
                        throw new IllegalArgumentException("Incomplete Generic packet.");
                
                if ((payload[0] & 0xFF) != APIFrameType.GENERIC.getValue())
                        throw new IllegalArgumentException("Payload is not a Generic packet.");
                
                // payload[0] is the frame type.
                int index = 1;
                
                byte[] commandData = null;
                if (index < payload.length)
                        commandData = Arrays.copyOfRange(payload, index, payload.length);
                
                return new GenericXBeePacket(commandData);
        }
        
        /**
         * Class constructor. Instantiates an XBee packet with the given packet 
         * data.
         * 
         * @param rfData The XBee RF Data.
         */
        public GenericXBeePacket(byte[] rfData) {
                super(APIFrameType.GENERIC);
                this.rfData = rfData;
                this.logger = LoggerFactory.getLogger(GenericXBeePacket.class);
        }
        
        /*
         * (non-Javadoc)
         * @see com.digi.xbee.api.packet.XBeeAPIPacket#getAPIPacketSpecificData()
         */
        @Override
        protected byte[] getAPIPacketSpecificData() {
                ByteArrayOutputStream data = new ByteArrayOutputStream();
                try {
                        if (rfData != null)
                                data.write(rfData);
                } catch (IOException e) {
                        logger.error(e.getMessage(), e);
                }
                return data.toByteArray();
        }
        
        /*
         * (non-Javadoc)
         * @see com.digi.xbee.api.packet.XBeeAPIPacket#needsAPIFrameID()
         */
        @Override
        public boolean needsAPIFrameID() {
                return false;
        }
        
        /**
         * Sets the XBee RF Data.
         * 
         * @param rfData The new XBee RF Data.
         */
        public void setRFData(byte[] rfData) {
                if (rfData == null)
                        this.rfData = null;
                else
                        this.rfData = Arrays.copyOf(rfData, rfData.length);
        }
        
        /**
         * Returns the XBee RF Data of the packet.
         * 
         * @return The RF Data.
         */
        public byte[] getRFData() {
                if (rfData == null)
                        return null;
                return Arrays.copyOf(rfData, rfData.length);
        }
        
        /*
         * (non-Javadoc)
         * @see com.digi.xbee.api.packet.XBeeAPIPacket#isBroadcast()
         */
        @Override
        public boolean isBroadcast() {
                return false;
        }
        
        /*
         * (non-Javadoc)
         * @see com.digi.xbee.api.packet.XBeeAPIPacket#getAPIPacketParameters()
         */
        @Override
        protected LinkedHashMap<String, String> getAPIPacketParameters() {
                LinkedHashMap<String, String> parameters = new LinkedHashMap<String, String>();
                if (rfData != null)
                        parameters.put("RF Data", HexUtils.prettyHexString(HexUtils.byteArrayToHexString(rfData)));
                return parameters;
        }
}