package at.acdp.urweb.rtde;

import at.acdp.urweb.rtde.packets.*;
import org.slf4j.LoggerFactory;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;
import java.util.HashMap;
import java.util.concurrent.Semaphore;

import static at.acdp.urweb.rtde.CommandType.*;

public class RTDEClient implements Runnable {
    private final static org.slf4j.Logger logger = LoggerFactory.getLogger(RTDEClient.class);
    private final Semaphore waitingRequestSem = new Semaphore(0);
    private volatile IRtdeData waitingRequest=null;

    public static int RTDE_PROTOCOL_VERSION = 2;
    private final String ip;
    private final int port;
    private volatile boolean _running = true;
    private volatile boolean initDone = false;

    private volatile DataOutputStream dos;
    private volatile DataInputStream dis;
    private Thread readThread;
    private RtdeSetupOutputs outputs;
    private HashMap<String, String> lastData;
    private RtdeSetupOutputs so;


    public RTDEClient(String ip, int port) {
        this.ip = ip;
        this.port = port;
    }

    public void start(RtdeSetupOutputs so) throws IOException, InterruptedException {
        this.so=so;
        readThread = new Thread(this);
        readThread.start();

    }

    public HashMap<String, String> getLastData() {
        return lastData;
    }

    public void request(IRtdeData data) throws IOException, InterruptedException {
        while(dos==null||dis==null) {
            Thread.sleep(100);
        }

        if(readThread.getId()==Thread.currentThread().getId()) {
            logger.error("request() must not be called from readThread.");
        }
        if(data.hasReply()) {
            waitingRequest=data;
        }
        data.send(dos);
        if(data.hasReply()) {
            waitingRequestSem.acquire();
            waitingRequest=null;
        }
        return;
    }


    private boolean init() throws IOException, InterruptedException {
        {
            var rpv = new RtdeRequestProtocolVersion();
            rpv.send(dos);
            int length = dis.readShort();
            int type = dis.readByte() & 0xFF;
            if(type!=RTDE_REQUEST_PROTOCOL_VERSION)
                return false;
            rpv.read(dis, length - 3);
            logger.info("RtdeRequestProtocolVersion succes:" + rpv.success);
        }
        {
            var ruv = new RtdeRequestURVersion();
            ruv.send(dos);
            int length=0;
            length = dis.readShort();
            int type = dis.readByte() & 0xFF;
            if(type!=RTDE_GET_URCONTROL_VERSION)
                return false;
            ruv.read(dis, length - 3);
            logger.info(String.format("RtdeRequestURVersion: %d.%d.%d.%d",ruv.major, ruv.minor, ruv.build, ruv.bugfix));
        }
        {
            so.send(dos);
            int length = dis.readShort();
            int type = dis.readByte() & 0xFF;
            if(type!=RTDE_CONTROL_PACKAGE_SETUP_OUTPUTS)
                return false;
            var r=so.read(dis, length - 1);
            logger.info("so:" +r.typesText);
            outputs=r;
        }
        {
            var start=new RtdeControlStart();
            start.send(dos);
            int length = dis.readShort();
            int type = dis.readByte() & 0xFF;
            if(type!=RTDE_CONTROL_PACKAGE_START)
                return false;
            start.read(dis, length -1);
            logger.info("start accepted:" +start.accepted);
            initDone=true;
        }
        return true;
    }

    private void handlePaket(int type, int length) throws IOException {
        var wreq=waitingRequest;
        if(wreq != null && type==wreq.getType()) {
            waitingRequest.read(dis, length-3);
            waitingRequestSem.release();
        } else switch(type) {
            case RTDE_TEXT_MESSAGE:
                var rpv = new RtdeTextMessage();
                rpv.read(dis, length-3);
                logger.info(String.format("RTDE_TEXT_MESSAGE: %s", rpv.text));
                break;
            case RTDE_DATA_PACKAGE:
                var p = new RtdeOutDataPackage(outputs);
                p.read(dis, length-3);
                lastData=p.getPdata();
                lastData.entrySet().forEach(entry->{
                    System.out.println(entry.getKey() + " " + entry.getValue());
                });
                break;

            default: {
                logger.warn(String.format("Unexpected package type: %d", type));
                byte[] buf=new byte[length];
                dis.readFully(buf);
            }
        }
    }


    @Override
    public void run() {
        while (_running) {
            initDone=false;
            try (Socket rt = new Socket(ip, port)){
                rt.setSoTimeout(10000);
                rt.setReuseAddress(true);
                rt.setTcpNoDelay(true);
                if (rt.isConnected()) {
                    logger.info("Connected to UR Realtime Client");
                    dos = new DataOutputStream(rt.getOutputStream());
                    dis = new DataInputStream(rt.getInputStream());
                    if(!init())
                        throw new IOException("init failed");
                    while (_running) {
                        int length = dis.readShort();
                        int type=dis.readByte() & 0xFF;
                        handlePaket(type, length);
                    }
                }
            } catch (IOException| InterruptedException e) {
                logger.warn("rtde connection closed", e);

            }
        }
    }
}