package com.freeone3000.android.elchat2.networklib;

import android.app.Service;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.IBinder;
import com.freeone3000.android.elchat2.Client;

import java.io.IOException;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.net.Socket;
import java.util.concurrent.*;

/**
 * Create a new instance, sendLogin(), invoke on a new thread, interrupt when needed.
 */
public class NetworkLibrary extends Service implements Callable<Void> {
    private final PriorityBlockingQueue<Packet> sendQueue = new PriorityBlockingQueue<Packet>();

    private Socket connection;
    private OutputStream output;
    private final NetworkReader reader = new NetworkReader();
    private Thread readThread;
    private Future<Void> thisFuture;

    @Override
    public void onCreate() {
        SharedPreferences pref = getSharedPreferences(Client.DATA_STORE, MODE_PRIVATE);
        String host = pref.getString("host", "game.eternal-lands.com");
        int port = pref.getInt("port", 2001);

        try {
            connection = new Socket(host, port);
            output = connection.getOutputStream();
            reader.setInput(connection.getInputStream());
            readThread = new Thread(reader, "NetworkReader");
            readThread.start();
        } catch(IOException ioe) {
            throw new RuntimeException("", ioe);
        }
    }

    @Override
    public void onStart(Intent intent, int startId) {
        ExecutorService ex = Executors.newSingleThreadExecutor();
        thisFuture = ex.submit(this);
    }

    /**
     * Main loop, queue-runner
     */
    public Void call() throws IOException {
        SharedPreferences pref = getSharedPreferences(Client.DATA_STORE, MODE_PRIVATE);
        String user = pref.getString("username", "");
        String pass = pref.getString("password", "");
        sendLogin(user, pass);

        while(!Thread.interrupted()) {
            Packet p;
            try {
                p = sendQueue.take();
            } catch(InterruptedException ie) {
                return null;
            }
            sendPacket(p);
        }
        return null;
    }

    private void sendLogin(final String username, final String password) throws IOException {
        sendQueue.put(new Packet(PacketTypes.LOG_IN, username + " " + password));
    }

    @Override
    public void onDestroy() {
        if(readThread != null) {
            readThread.interrupt();
        }
        if(connection != null) {
            try {
                connection.close();
            } catch(IOException ioe) {
                throw new RuntimeException("", ioe);
            }
        }
        if(thisFuture != null) {
            thisFuture.cancel(true);
        }
    }

    private void sendPacket(final Packet packet) throws IOException {
        try {
            sendPacket(packet.getType(), packet.getData().getBytes("US-ASCII"));
        } catch(UnsupportedEncodingException uee) {
            throw new RuntimeException("US-ASCII must be a valid charset!", uee);
        }
    }

    private void sendPacket(final byte type, final byte[] payload) throws IOException {
        byte[] dat = new byte[payload.length + 4]; //+1 for type, +2 for size, +1 for trailing '\0'
        dat[0] = type;
        int size = payload.length + 2; //+1 for header, +1 for trailing 0
        dat[1] = (byte)(size & 0xFF);
        dat[2] = (byte)((size >>> 8) & 0xFF);
        System.arraycopy(payload, 0, dat, 3, payload.length);
        output.write(dat);
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;  //TODO Implement
    }
}