/*
 * Copyright 2012 - 2016 Anton Tananaev (anton.tananaev@gmail.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.traccar.protocol;

import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.traccar.BaseProtocolDecoder;
import org.traccar.helper.BcdUtil;
import org.traccar.helper.BitUtil;
import org.traccar.helper.DateBuilder;
import org.traccar.helper.Parser;
import org.traccar.helper.PatternBuilder;
import org.traccar.model.Position;

import java.net.SocketAddress;
import java.nio.charset.StandardCharsets;
import java.util.Date;
import java.util.regex.Pattern;

public class H02ProtocolDecoder extends BaseProtocolDecoder {

    public H02ProtocolDecoder(H02Protocol protocol) {
        super(protocol);
    }

    private static double readCoordinate(ChannelBuffer buf, boolean lon) {

        int degrees = BcdUtil.readInteger(buf, 2);
        if (lon) {
            degrees = degrees * 10 + (buf.getUnsignedByte(buf.readerIndex()) >> 4);
        }

        double result = 0;
        if (lon) {
            result = buf.readUnsignedByte() & 0x0f;
        }

        int length = 6;
        if (lon) {
            length = 5;
        }

        result = result * 10 + BcdUtil.readInteger(buf, length) * 0.0001;

        result /= 60;
        result += degrees;

        return result;
    }

    private void processStatus(Position position, long status) {
        if (!BitUtil.check(status, 0) || !BitUtil.check(status, 1)
                || !BitUtil.check(status, 3) || !BitUtil.check(status, 4) || !BitUtil.check(status, 7)) {
            position.set(Position.KEY_ALARM, true);

            if (!BitUtil.check(status, 0)){
                position.set(Position.KEY_ALARM_TYPE, "theft");
            } else if (!BitUtil.check(status, 1)){
                position.set(Position.KEY_ALARM_TYPE, "robbery");
            } else if (!BitUtil.check(status, 3)){
                position.set(Position.KEY_ALARM_TYPE, "illegal ignition");
            } else if (!BitUtil.check(status, 4)){
                position.set(Position.KEY_ALARM_TYPE, "entering");
            } else if (!BitUtil.check(status, 7)){
                position.set(Position.KEY_ALARM_TYPE, "out");
            }

        }
        position.set(Position.KEY_IGNITION, !BitUtil.check(status, 10));
        position.set(Position.KEY_STATUS, status);
    }

    private Position decodeBinary(ChannelBuffer buf, Channel channel, SocketAddress remoteAddress) {

        Position position = new Position();
        position.setProtocol(getProtocolName());

        buf.readByte(); // marker

        if (!identify(ChannelBuffers.hexDump(buf.readBytes(5)), channel, remoteAddress)) {
            return null;
        }
        position.setDeviceId(getDeviceId());

        DateBuilder dateBuilder = new DateBuilder()
                .setHour(BcdUtil.readInteger(buf, 2))
                .setMinute(BcdUtil.readInteger(buf, 2))
                .setSecond(BcdUtil.readInteger(buf, 2))
                .setDay(BcdUtil.readInteger(buf, 2))
                .setMonth(BcdUtil.readInteger(buf, 2))
                .setYear(BcdUtil.readInteger(buf, 2));
        position.setTime(dateBuilder.getDate());

        double latitude = readCoordinate(buf, false);
        position.set(Position.KEY_POWER, buf.readByte());
        double longitude = readCoordinate(buf, true);

        int flags = buf.readUnsignedByte() & 0x0f;
        position.setValid((flags & 0x02) != 0);
        if ((flags & 0x04) == 0) {
            latitude = -latitude;
        }
        if ((flags & 0x08) == 0) {
            longitude = -longitude;
        }

        position.setLatitude(latitude);
        position.setLongitude(longitude);

        position.setSpeed(BcdUtil.readInteger(buf, 3));
        position.setCourse((buf.readUnsignedByte() & 0x0f) * 100.0 + BcdUtil.readInteger(buf, 2));

        processStatus(position, buf.readUnsignedInt());
        return position;
    }

    private static final Pattern PATTERN = new PatternBuilder()
            .text("*")
            .expression("..,")                   // manufacturer
            .number("(d+),")                     // imei
            .number("Vd,")                       // version?
            .any()
            .number("(?:(dd)(dd)(dd))?,")        // time
            .expression("([AV])?,")              // validity
            .groupBegin()
            .number("-(d+)-(d+.d+),")            // latitude
            .or()
            .number("(d+)(dd.d+),")              // latitude
            .groupEnd()
            .expression("([NS]),")
            .groupBegin()
            .number("-(d+)-(d+.d+),")            // longitude
            .or()
            .number("(d+)(dd.d+),")              // longitude
            .groupEnd()
            .expression("([EW]),")
            .number("(d+.?d*),")                 // speed
            .number("(d+.?d*)?,")                // course
            .number("(?:(dd)(dd)(dd))?,")        // date (ddmmyy)
            .number("(x{8})")                    // status
            .any()
            .compile();

    private Position decodeText(String sentence, Channel channel, SocketAddress remoteAddress) {

        Parser parser = new Parser(PATTERN, sentence);
        if (!parser.matches()) {
            return null;
        }

        Position position = new Position();
        position.setProtocol(getProtocolName());

        if (!identify(parser.next(), channel, remoteAddress)) {
            return null;
        }
        position.setDeviceId(getDeviceId());

        DateBuilder dateBuilder = new DateBuilder();
        if (parser.hasNext(3)) {
            dateBuilder.setTime(parser.nextInt(), parser.nextInt(), parser.nextInt());
        }

        if (parser.hasNext()) {
            position.setValid(parser.next().equals("A"));
        }

        if (parser.hasNext(2)) {
            position.setLatitude(-parser.nextCoordinate());
        }
        if (parser.hasNext(2)) {
            position.setLatitude(parser.nextCoordinate());
        }

        if (parser.hasNext(2)) {
            position.setLongitude(-parser.nextCoordinate());
        }
        if (parser.hasNext(2)) {
            position.setLongitude(parser.nextCoordinate());
        }

        position.setSpeed(parser.nextDouble());
        position.setCourse(parser.nextDouble());

        if (parser.hasNext(3)) {
            dateBuilder.setDateReverse(parser.nextInt(), parser.nextInt(), parser.nextInt());
            position.setTime(dateBuilder.getDate());
        } else {
            position.setTime(new Date());
        }

        processStatus(position, parser.nextLong(16));

        return position;
    }

    @Override
    protected Object decode(
            Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {

        ChannelBuffer buf = (ChannelBuffer) msg;
        String marker = buf.toString(0, 1, StandardCharsets.US_ASCII);

        // handle X mode?

        if (marker.equals("*")) {
            return decodeText(buf.toString(StandardCharsets.US_ASCII), channel, remoteAddress);
        } else if (marker.equals("$")) {
            return decodeBinary(buf, channel, remoteAddress);
        }

        return null;
    }

}