<uses-permission android:name="android.permission.NFC" />

<uses-feature android:name="android.hardware.nfc" />

package com.ramzey.nfcokuma2025;

import android.app.PendingIntent;
import android.content.Intent;
import android.content.IntentFilter;
import android.nfc.NdefMessage;
import android.nfc.NdefRecord;
import android.nfc.NfcAdapter;
import android.nfc.tech.IsoDep;
import android.nfc.tech.MifareClassic;
import android.nfc.tech.MifareUltralight;
import android.nfc.tech.Ndef;
import android.nfc.tech.NfcA;
import android.nfc.tech.NfcB;
import android.nfc.tech.NfcF;
import android.nfc.tech.NfcV;
import android.os.Build;
import android.os.Bundle;
import android.os.Parcelable;
import android.util.Log;
import android.widget.TextView;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

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

public class MainActivity extends AppCompatActivity {

    TextView txtNfc;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Log.d("1111", "aaaa");
        txtNfc = findViewById(R.id.txtNfc);

    }

    // list of NFC technologies detected:
    private final String[][] techList = new String[][]{
            new String[]{
                    NfcA.class.getName(),
                    NfcB.class.getName(),
                    NfcF.class.getName(),
                    NfcV.class.getName(),
                    IsoDep.class.getName(),
                    MifareClassic.class.getName(),
                    MifareUltralight.class.getName(), Ndef.class.getName()
            }
    };

    @Override
    protected void onResume() {
        super.onResume();
        // creating pending intent:

        PendingIntent pendingIntent;
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
            pendingIntent = PendingIntent.getActivity(this,
                    0, new Intent(this, getClass()).addFlags(
                            Intent.FLAG_ACTIVITY_SINGLE_TOP),
                    PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_MUTABLE);
        } else {
            pendingIntent = PendingIntent.getActivity(this,
                    0, new Intent(this, getClass()).addFlags(
                            Intent.FLAG_ACTIVITY_SINGLE_TOP),
                    PendingIntent.FLAG_UPDATE_CURRENT);
        }


        // creating intent receiver for NFC events:
        IntentFilter filter = new IntentFilter();
        filter.addAction(NfcAdapter.ACTION_TAG_DISCOVERED);
        filter.addAction(NfcAdapter.ACTION_NDEF_DISCOVERED);
        filter.addAction(NfcAdapter.ACTION_TECH_DISCOVERED);
        // enabling foreground dispatch for getting intent from NFC event:
        NfcAdapter nfcAdapter = NfcAdapter.getDefaultAdapter(this);
        nfcAdapter.enableForegroundDispatch(this, pendingIntent, new IntentFilter[]{filter}, this.techList);
    }

    @Override
    protected void onPause() {
        super.onPause();
        // disabling foreground dispatch:
        NfcAdapter nfcAdapter = NfcAdapter.getDefaultAdapter(this);
        nfcAdapter.disableForegroundDispatch(this);
    }

    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);
        Toast.makeText(this, "NFC OKUNDU!", Toast.LENGTH_SHORT).show();
        NfcAdapter nfcAdapter = NfcAdapter.getDefaultAdapter(this);
        txtNfc.setText("EXTRA_ID : "+ByteArrayToHexString(intent.getByteArrayExtra(NfcAdapter.EXTRA_ID))); // EXTRA_ID

        Parcelable[] rawMessages = intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);
        NdefMessage[] messages = null;
        if (rawMessages != null) {
            messages = new NdefMessage[rawMessages.length];
            for (int i = 0; i < rawMessages.length; i++) {
                messages[i] = (NdefMessage) rawMessages[i];
                NdefRecord[] records = messages[i].getRecords();
                //if you are sure you have text then you don't need to test TNF
                for(NdefRecord record: records){
                    processRecord(record);
                }
            }
        }
    }

    public void processRecord(NdefRecord record) {

        short tnf = record.getTnf();
        switch (tnf) {

            case NdefRecord.TNF_WELL_KNOWN: {
                if (Arrays.equals(record.getType(), NdefRecord.RTD_TEXT)) {
                    String yourtext = processRtdTextRecord(record.getPayload());
                    txtNfc.setText(txtNfc.getText().toString()+"\nrecord : "+yourtext);
                } else if (Arrays.equals(record.getType(), NdefRecord.RTD_URI)) {
                    String yourtext = record.toUri().toString();
                    txtNfc.setText(txtNfc.getText().toString()+"\nrecord : "+yourtext);
                } else if (Arrays.equals(record.getType(), NdefRecord.RTD_SMART_POSTER)) {
                   // processSmartPosterRecord(record);
                } else {
                    //Record is not Text or URI or Poster
                }
            }
            case NdefRecord.TNF_MIME_MEDIA: {
                if (record.toMimeType().equals("MIME/Type")) {
                    // handle this as you want
                } else {
                    //Record is not our MIME
                }
            }
            // you can write more cases
            default: {
                //unsupported NDEF Record
            }
        }
    }

    private String processRtdTextRecord(byte[] payload) {
        String textEncoding = ((payload[0] & 128) == 0) ? "UTF-8" : "UTF-16";
        int languageCodeLength = payload[0] & 0063;

        String text = "";
        try {
            text = new String(payload, languageCodeLength + 1, payload.length - languageCodeLength - 1, textEncoding);
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
            Log.e("UnsupportedEncoding", e.toString());
        }
        return text;
    }

    private String ByteArrayToHexString(byte[] inarray) {
        int i, j, in;
        String[] hex = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F"};
        String out = "";

        for (j = 0; j < inarray.length; ++j) {
            in = (int) inarray[j] & 0xff;
            i = (in >> 4) & 0x0f;
            out += hex[i];
            i = in & 0x0f;
            out += hex[i];
        }
        return out;
    }


}