heartbeatapp/app/src/main/java/com/rubenvandeven/heartbeatstreamer/MainActivity.java

package com.rubenvandeven.heartbeatstreamer;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
import android.widget.Toast;

import com.rubenvandeven.heartbeatstreamer.heartrate.Activity_AsyncScanHeartRateSampler;
import com.rubenvandeven.heartbeatstreamer.heartrate.Activity_SearchUiHeartRateSampler;
import com.rubenvandeven.heartbeatstreamer.heartrate.HeartRateService;

import org.json.JSONException;
import org.json.JSONObject;

import java.io.IOException;
import java.io.InputStream;
import java.text.SimpleDateFormat;
import java.util.Date;

public class MainActivity extends AppCompatActivity {

    private final String TAG = MainActivity.class.getSimpleName();

    private TextView statusLabel;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        statusLabel = findViewById(R.id.status_msg);

        setup();

        startHeartRateMonitor();


    }


    @Override
    protected void onResume() {
        super.onResume();
        setup();
    }

    public void setup() {
        if (HeartRateService.isRunning()) {
            statusLabel.setText("Running");
        } else {
            statusLabel.setText("Stopped");
        }
        registerBroadcastReceiver();
    }

    public void startHeartRateMonitor() {
        if(HeartRateService.isRunning()) {
            Toast.makeText(this, "Already running", Toast.LENGTH_LONG);
        } else {
            Intent intent = new Intent(MainActivity.this, HeartRateService.class);
            startService(intent);
        }
    }

    public void stopHeartRateMonitor() {
        // stop tracking
        Intent intent = new Intent(MainActivity.this, HeartRateService.class);
        stopService(intent);
    }

    /**
     * Register broadcast receiver for synchronization
     * and tracking status updates
     */
    private void registerBroadcastReceiver() {
        Log.d(TAG, "register broadcastreceiver");
        IntentFilter filter = new IntentFilter();
        filter.addAction(HeartRateService.BROADCAST_MONITOR_CONNECTED);
        filter.addAction(HeartRateService.BROADCAST_MONITOR_DISCONNECTED);
        filter.addAction(HeartRateService.BROADCAST_MONITOR_UPDATE);
        filter.addAction(HeartRateService.BROADCAST_MONITOR_UNKNOWN);
        filter.addAction(HeartRateService.BROADCAST_SOCKET_SENT);
        registerReceiver(mBroadcastReceiver, filter);
    }

    /**
     * On pause
     */
    @Override
    protected void onPause() {
        unregisterReceiver(mBroadcastReceiver);
//        if (db != null) {
//            db.close();
//        }
        super.onPause();
    }

    /**
     * Broadcast receiver
     */
    private final BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            Log.d(TAG, "[broadcast received " + intent + "]");
            if (intent == null || intent.getAction() == null) {
                return;
            }
            switch (intent.getAction()) {
                case HeartRateService.BROADCAST_MONITOR_CONNECTED:
                    statusLabel.setText("Running");
                    break;
                case HeartRateService.BROADCAST_MONITOR_DISCONNECTED:
                    statusLabel.setText("Stopped");
                    break;
                case HeartRateService.BROADCAST_MONITOR_UPDATE:
                    SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd_HHmmss");
                    String currentDateandTime = sdf.format(new Date());
                    statusLabel.setText("Last update: %s".format(currentDateandTime));
                    break;

                case HeartRateService.BROADCAST_SOCKET_SENT:
                    String msg = intent.getStringExtra("msg");
                    statusLabel.setText("Last msg: %s".format(msg));
                    break;
            }
        }
    };

    /**
     * Get the token for use with the syncing.
     * @return
     */
    public String getToken() {
        String json = null;
        String token = null;

        try {
            InputStream is = getAssets().open("token.json");
            int size = is.available();
            byte[] buffer = new byte[size];
            is.read(buffer);
            is.close();
            json = new String(buffer, "UTF-8");
        } catch (IOException ex) {
            ex.printStackTrace();
            return null;
        }
        try {
            JSONObject jsonObject = new JSONObject(json);
            token = jsonObject.getString("token'");
        } catch (JSONException e) {
            e.printStackTrace();
            return null;
        }
        return token;
    }

}