package com.example.nfctagread;

import java.io.UnsupportedEncodingException;
import java.util.Arrays;

import android.app.Activity;
import android.app.PendingIntent;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.IntentFilter.MalformedMimeTypeException;
import android.nfc.NdefMessage;
import android.nfc.NdefRecord;
import android.nfc.NfcAdapter;
import android.nfc.Tag;
import android.nfc.tech.Ndef;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;

public class MainActivity extends Activity {

	 public static final String MIME_TEXT_PLAIN = "text/plain";
	    public static final String TAG = "NfcDemo";
	    private NfcAdapter mNfcAdapter;
	    private TextView text1;
	    @Override
	    protected void onCreate(Bundle savedInstanceState) {
	        super.onCreate(savedInstanceState);
	        setContentView(R.layout.activity_main);
	        text1=(TextView)findViewById(R.id.textView1);
	        mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
	        if (mNfcAdapter == null) {
	            finish();
	            return;
	        }
	        if (!mNfcAdapter.isEnabled()) {
	    //        mTextView.setText("NFC is disabled.");
	        } else {
	     //       mTextView.setText(R.string.explanation);
	        }
	        handleIntent(getIntent());
	    }
	    
	    @Override
	    protected void onResume() {
	        super.onResume();
	        setupForegroundDispatch(this, mNfcAdapter);
	    }
	    @Override
	    protected void onPause() {
	        stopForegroundDispatch(this, mNfcAdapter);
	        super.onPause();
	    }
	    @Override
	    protected void onNewIntent(Intent intent) {
	        handleIntent(intent);
	    }
	
	    public static void setupForegroundDispatch(final Activity activity, NfcAdapter adapter) {
	        final Intent intent = new Intent(activity.getApplicationContext(), activity.getClass());
	        intent.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
	        final PendingIntent pendingIntent = PendingIntent.getActivity(activity.getApplicationContext(), 0, intent, 0);
	        IntentFilter[] filters = new IntentFilter[1];
	        String[][] techList = new String[][]{};
	        // Notice that this is the same filter as in our manifest.
	        filters[0] = new IntentFilter();
	        filters[0].addAction(NfcAdapter.ACTION_NDEF_DISCOVERED);
	        filters[0].addCategory(Intent.CATEGORY_DEFAULT);
	        try {
	            filters[0].addDataType(MIME_TEXT_PLAIN);
	        } catch (MalformedMimeTypeException e) {
	            throw new RuntimeException("Check your mime type.");
	        }
	        adapter.enableForegroundDispatch(activity, pendingIntent, filters, techList);
	    }
	    
	    public static void stopForegroundDispatch(final Activity activity, NfcAdapter adapter) {
	        adapter.disableForegroundDispatch(activity);
	    }
	    
	    
	    
	    
	    
	private void handleIntent(Intent intent) {
	    String action = intent.getAction();
	    if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(action)) {
	        String type = intent.getType();
	        if (MIME_TEXT_PLAIN.equals(type)) {
	            Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
	            new NdefReaderTask().execute(tag);
	        } else {
	            Log.d(TAG, "Wrong mime type: " + type);
	        }
	    } else if (NfcAdapter.ACTION_TECH_DISCOVERED.equals(action)) {
	        Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
	        String[] techList = tag.getTechList();
	        String searchedTech = Ndef.class.getName();
	        for (String tech : techList) {
	            if (searchedTech.equals(tech)) {
	                new NdefReaderTask().execute(tag);
	                break;
	            }
	        }
	    }
	}
	
	private class NdefReaderTask extends AsyncTask<Tag, Void, String> {
	    @Override
	    protected String doInBackground(Tag... params) {
	        Tag tag = params[0];
	        Ndef ndef = Ndef.get(tag);
	        if (ndef == null) {
	            return null;
	        }
	        NdefMessage ndefMessage = ndef.getCachedNdefMessage();
	        NdefRecord[] records = ndefMessage.getRecords();
	        for (NdefRecord ndefRecord : records) {
	            if (ndefRecord.getTnf() == NdefRecord.TNF_WELL_KNOWN && Arrays.equals(ndefRecord.getType(), NdefRecord.RTD_TEXT)) {
	                try {
	                    return readText(ndefRecord);
	                } catch (UnsupportedEncodingException e) {
	                    Log.e(TAG, "Unsupported Encoding", e);
	                }
	            }
	        }
	        return null;
	    }
	    private String readText(NdefRecord record) throws UnsupportedEncodingException {
	        byte[] payload = record.getPayload();
	        String textEncoding = ((payload[0] & 128) == 0) ? "UTF-8" : "UTF-16";
	        int languageCodeLength = payload[0] & 0063;
	        return new String(payload, languageCodeLength + 1, payload.length - languageCodeLength - 1, textEncoding);
	    }
	    @Override
	    protected void onPostExecute(String result) {
	        if (result != null) {
	          text1.setText(result);
	        }
	    }
	
	}
	
}