1 files changed, 165 insertions, 0 deletions
diff --git a/src/android/app/src/main/java/org/yuzu/yuzu_emu/utils/NfcReader.kt b/src/android/app/src/main/java/org/yuzu/yuzu_emu/utils/NfcReader.kt
new file mode 100644
index 000000000..1ce220d42
--- /dev/null
+++ b/src/android/app/src/main/java/org/yuzu/yuzu_emu/utils/NfcReader.kt
@@ -0,0 +1,165 @@
+package org.yuzu.yuzu_emu.utils
+
+import android.app.Activity
+import android.app.PendingIntent
+import android.content.Intent
+import android.content.IntentFilter
+import android.nfc.NfcAdapter
+import android.nfc.Tag
+import android.nfc.tech.NfcA
+import android.os.Build
+import android.os.Handler
+import android.os.Looper
+import org.yuzu.yuzu_emu.NativeLibrary
+import java.io.IOException
+
+class NfcReader(private val activity: Activity) {
+    private var nfcAdapter: NfcAdapter? = null
+    private var pendingIntent: PendingIntent? = null
+
+    fun initialize() {
+        nfcAdapter = NfcAdapter.getDefaultAdapter(activity) ?: return
+
+        pendingIntent = PendingIntent.getActivity(
+            activity,
+            0, Intent(activity, activity.javaClass),
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S)
+                PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_MUTABLE
+            else PendingIntent.FLAG_UPDATE_CURRENT
+        )
+
+        val tagDetected = IntentFilter(NfcAdapter.ACTION_TAG_DISCOVERED)
+        tagDetected.addCategory(Intent.CATEGORY_DEFAULT)
+    }
+
+    fun startScanning() {
+        nfcAdapter?.enableForegroundDispatch(activity, pendingIntent, null, null)
+    }
+
+    fun stopScanning() {
+        nfcAdapter?.disableForegroundDispatch(activity)
+    }
+
+    fun onNewIntent(intent: Intent) {
+        val action = intent.action
+        if (NfcAdapter.ACTION_TAG_DISCOVERED != action
+            && NfcAdapter.ACTION_TECH_DISCOVERED != action
+            && NfcAdapter.ACTION_NDEF_DISCOVERED != action
+        ) {
+            return
+        }
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+            val tag =
+                intent.getParcelableExtra(NfcAdapter.EXTRA_TAG, Tag::class.java) ?: return
+            readTagData(tag)
+            return
+        }
+
+        val tag =
+            intent.getParcelableExtra<Tag>(NfcAdapter.EXTRA_TAG) ?: return
+        readTagData(tag)
+    }
+
+    private fun readTagData(tag: Tag) {
+        if (!tag.techList.contains("android.nfc.tech.NfcA")) {
+            return
+        }
+
+        val amiibo = NfcA.get(tag) ?: return
+        amiibo.connect()
+
+        val tagData = ntag215ReadAll(amiibo) ?: return
+        NativeLibrary.onReadNfcTag(tagData)
+
+        nfcAdapter?.ignore(
+            tag,
+            1000,
+            { NativeLibrary.onRemoveNfcTag() },
+            Handler(Looper.getMainLooper())
+        )
+    }
+
+    private fun ntag215ReadAll(amiibo: NfcA): ByteArray? {
+        val bufferSize = amiibo.maxTransceiveLength;
+        val tagSize = 0x21C
+        val pageSize = 4
+        val lastPage = tagSize / pageSize - 1
+        val tagData = ByteArray(tagSize)
+
+        // We need to read the ntag in steps otherwise we overflow the buffer
+        for (i in 0..tagSize step bufferSize - 1) {
+            val dataStart = i / pageSize
+            var dataEnd = (i + bufferSize) / pageSize
+
+            if (dataEnd > lastPage) {
+                dataEnd = lastPage
+            }
+
+            try {
+                val data = ntag215FastRead(amiibo, dataStart, dataEnd - 1)
+                System.arraycopy(data, 0, tagData, i, (dataEnd - dataStart) * pageSize)
+            } catch (e: IOException) {
+                return null;
+            }
+        }
+        return tagData
+    }
+
+    private fun ntag215Read(amiibo: NfcA, page: Int): ByteArray? {
+        return amiibo.transceive(
+            byteArrayOf(
+                0x30.toByte(),
+                (page and 0xFF).toByte()
+            )
+        )
+    }
+
+    private fun ntag215FastRead(amiibo: NfcA, start: Int, end: Int): ByteArray? {
+        return amiibo.transceive(
+            byteArrayOf(
+                0x3A.toByte(),
+                (start and 0xFF).toByte(),
+                (end and 0xFF).toByte()
+            )
+        )
+    }
+
+    private fun ntag215PWrite(
+        amiibo: NfcA,
+        page: Int,
+        data1: Int,
+        data2: Int,
+        data3: Int,
+        data4: Int
+    ): ByteArray? {
+        return amiibo.transceive(
+            byteArrayOf(
+                0xA2.toByte(),
+                (page and 0xFF).toByte(),
+                (data1 and 0xFF).toByte(),
+                (data2 and 0xFF).toByte(),
+                (data3 and 0xFF).toByte(),
+                (data4 and 0xFF).toByte()
+            )
+        )
+    }
+
+    private fun ntag215PwdAuth(
+        amiibo: NfcA,
+        data1: Int,
+        data2: Int,
+        data3: Int,
+        data4: Int
+    ): ByteArray? {
+        return amiibo.transceive(
+            byteArrayOf(
+                0x1B.toByte(),
+                (data1 and 0xFF).toByte(),
+                (data2 and 0xFF).toByte(),
+                (data3 and 0xFF).toByte(),
+                (data4 and 0xFF).toByte()
+            )
+        )
+    }
+}