package com.example.user.waterpumpcontrol;

import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;

public class MainActivity extends AppCompatActivity {

    private BluetoothAdapter BA;
    private int REQUEST_ENABLE_BT = 1;
    private static final String APC = "PUMPCTRL";         // HC-05 Bluetooth module device name
    private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");   // HC-05 Bluetooth module unique ID
    private BluetoothDevice mmDevice;           // BT connected device
    private OutputStream mmOutputStream;        // BT application output
    private InputStream mmInputStream;          // BT application input
    private int btConnected;               // conformation that BT is connected

    Thread workerThread;
    Handler bluetoothIn;
    final int handlerState = 0;         // used to identify handler message (only using one msg)
    private StringBuilder recDataString = new StringBuilder();

    Button btnSetIdle, btnRtvIdle, btnFlush;
    TextView tvTempP, tvTempRadIn, tvTempRadOut, tvFlowPrime, tvFlowSecond, tvPStatus;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // menu items
        setContentView(R.layout.activity_main);

        // buttons
        btnSetIdle = (Button) findViewById(R.id.setValBtn);
        btnRtvIdle = (Button) findViewById(R.id.rtValBtn);
        btnFlush = (Button) findViewById(R.id.flushBtn);

        // updatable text fields
        tvTempP = (TextView) findViewById(R.id.tempReadP);
        tvTempRadIn = (TextView) findViewById(R.id.tempReadIn);
        tvTempRadOut = (TextView) findViewById(R.id.tempReadOut);
        tvFlowPrime = (TextView) findViewById(R.id.flowRead1);
        tvFlowSecond = (TextView) findViewById(R.id.flowRead2);
        tvPStatus = (TextView) findViewById(R.id.pumpStatus);

        // Register the BroadcastReceiver
        IntentFilter filter = new IntentFilter();

        filter.addAction(BluetoothDevice.ACTION_FOUND);
        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
        filter.addAction(BluetoothAdapter.ACTION_STATE_CHANGED);

        registerReceiver(mReceiver, filter); // Don't forget to unregister during onDestroy

        BA = BluetoothAdapter.getDefaultAdapter();

        bluetoothIn = new Handler() {
            public void handleMessage(android.os.Message msg) {
                if (msg.what == handlerState) {//if message is what we want
                    //Toast.makeText(MainActivity.this, "DATA RECEIVED", Toast.LENGTH_SHORT).show();
                    byte[] readBuf = (byte[]) msg.obj;
                    String readMessage = new String(readBuf, 0, msg.arg1);                 // msg.arg1 = bytes from connect thread; converting to string
                    recDataString.append(readMessage);                                    //~: always the last character in a string from the Arduino
                    //Toast.makeText(MainActivity.this, readMessage, Toast.LENGTH_SHORT).show();
                    int endOfLineIndex = recDataString.indexOf("~");                    // determine the end-of-line
                    if (endOfLineIndex > 0) {                                           // make sure there data before ~
                        if (recDataString.charAt(0) == '#')                             //if it starts with # we know it is what we are looking for
                        {
                            String tempPRead = recDataString.substring(1, 5);             //get sensor value from string between indices 1-5
                            String tempRadInRead = recDataString.substring(5, 9);            //same again...
                            String tempRadOutRead = recDataString.substring(9, 13);
                            String flow1Read = recDataString.substring(13, 17);
                            String flow2Read = recDataString.substring(17, 21);


                            tvTempP.setText(tempPRead);                     //update the textviews with sensor values
                            tvTempRadIn.setText(tempRadInRead);
                            tvTempRadOut.setText(tempRadOutRead);
                            tvFlowPrime.setText(flow1Read);
                            tvFlowSecond.setText(flow2Read);
                        }
                        else if (recDataString.charAt(0) == '?')                             //if it starts with ?, conformation of idle values set
                        {
                            Toast.makeText(MainActivity.this, "Idle conditions set.", Toast.LENGTH_SHORT).show();
                        }
                        else if (recDataString.charAt(0) == '!')                             //if it starts with !, idle sensor values have been sent
                        {
                            int idleFlowStart = recDataString.indexOf("+");     //the separator between both sensor readings sent as a combined string

                            String idleTemp = recDataString.substring(1, idleFlowStart);
                            String idleFlow = recDataString.substring((idleFlowStart+1), endOfLineIndex);

                            String toast = "Temp C= " + idleTemp + ", Flow L/min= " + idleFlow;

                            Toast.makeText(MainActivity.this, toast, Toast.LENGTH_SHORT).show();
                        }
                        else if (recDataString.charAt(0) == '$')                             //if it starts with $, pump will turn on for 10sec
                        {
                            Toast.makeText(MainActivity.this, "Pump on for 20 seconds.", Toast.LENGTH_SHORT).show();
                        }
                        else if (recDataString.charAt(0) == '*')                             //if it starts with *, update pump on/off status
                        {
                            if (recDataString.charAt(1) == '1'){
                                tvPStatus.setText("ON");
                            }
                            else if (recDataString.charAt(1) == '2'){
                                tvPStatus.setText("OFF");
                            }
                        }
                        recDataString.delete(0, recDataString.length());                    //clear all string data
                    }
                }
            }
        };

        // onclick button listeners

        btnSetIdle.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {       // if button "set idle conditions" is pressed
                try {
                    sendData(1);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        });

        btnRtvIdle.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {       // if button "retrieve idle conditions" is pressed
                try {
                    sendData(2);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        });

        btnFlush.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {       // if button "flush coolant system" is pressed
                try {
                    sendData(3);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        });

    }

    @Override
    public void onDestroy() {
        unregisterReceiver(mReceiver);

        if (BA.isDiscovering()) {
            BA.cancelDiscovery();
        }

        super.onDestroy();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        // if "Connect to Bluetooth" is selected from the menu
        if (id == R.id.action_settings) {

            if (BA != null) {
                if (!BA.isEnabled()) {
                    enableBT(0);
                } else {
                    searchConnect();
                }
            } else {
                Toast.makeText(MainActivity.this, "No Bluetooth adapter found.", Toast.LENGTH_SHORT).show();
            }

        }

        return super.onOptionsItemSelected(item);
    }


    public int enableBT(int msg) {

        if (msg == 1) {
            Toast.makeText(MainActivity.this, "Bluetooth must remain enabled for app use.", Toast.LENGTH_SHORT).show();
        }

        Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
        startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);

        return 0;
    }

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == REQUEST_ENABLE_BT) {
            if (resultCode == RESULT_OK) {
                Toast.makeText(MainActivity.this, "Bluetooth enabled.", Toast.LENGTH_SHORT).show();
                searchConnect();
            } else {
                Toast.makeText(MainActivity.this, "Please enable Bluetooth.", Toast.LENGTH_SHORT).show();
                enableBT(0);
            }
        }
    }

    public void searchConnect() {

        BA.startDiscovery();

    }

    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            Bundle extras = intent.getExtras();
            final int FAIL = -1;

            if (BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)) {
                Toast.makeText(MainActivity.this, "BT discovery started.", Toast.LENGTH_SHORT).show();          // search for PUMPCTRL has started
            }
            else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
                Toast.makeText(MainActivity.this, "BT discovery finished.", Toast.LENGTH_SHORT).show();         // search for PUMPCTRL has finished
            }
            else if (BluetoothDevice.ACTION_FOUND.equals(action)) {         // bluetooth device found
                BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);

                if (device.getName().equals(APC)) {             // if one of the Bluetooth devices are named "PUMPCTRL", connect to it
                    mmDevice = device;
                    try {
                        openBT();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
            else if ("android.bluetooth.adapter.action.STATE_CHANGED".equals(action)) {
                bluetoothStateChanged(extras.getInt("android.bluetooth.adapter.extra.STATE", FAIL));
            }
        }
    };

    private void bluetoothStateChanged(int state) {
        switch (state) {
            case BluetoothAdapter.STATE_OFF: {
                break;
            }
            case BluetoothAdapter.STATE_TURNING_ON: {
                break;
            }
            case BluetoothAdapter.STATE_ON: {
                break;
            }
            case BluetoothAdapter.STATE_TURNING_OFF: {      // if BT is turned off while using app, turn it back on
                enableBT(1);
                break;
            }
        }
    }

    void openBT() throws IOException {
        BluetoothSocket mmSocket = mmDevice.createRfcommSocketToServiceRecord(MY_UUID);
        mmSocket.connect();
        mmOutputStream = mmSocket.getOutputStream();
        mmInputStream = mmSocket.getInputStream();
        btConnected = 1;
        beginListenForData();
    }

    void beginListenForData() {

        workerThread = new Thread(new Runnable() {                                                                  // A thread is used to perform intensive tasks in the background
            public void run() {                                                                                     // of a main activity in order to prevent visible lag to the user

                byte[] readBuffer = new byte[512];
                int msgLength;

                while(true) {
                    try {
                        int bytesAvailable = mmInputStream.available();
                        if(bytesAvailable > 0) {                                                                    // if there is a transmission to receive
                            msgLength = mmInputStream.read(readBuffer);                                             // store bytes in buffer variable
                            bluetoothIn.obtainMessage(handlerState, msgLength, -1, readBuffer).sendToTarget();      // send buffer data of length "msgLength" out of work thread to
                        }                                                                                           // handler for output on main activity window
                    }
                    catch (IOException ex) {
                        break;
                    }
                }
            }
        });

        workerThread.start();
    }

    void sendData(int i) throws IOException {
        if(btConnected == 1){
            mmOutputStream.write(i);
        }
        else{
            Toast.makeText(MainActivity.this, "Bluetooth not connected.", Toast.LENGTH_SHORT).show();
        }
    }

}