primary functions

.idea/deploymentTargetSelector.xml

@@ -5,6 +5,9 @@
       <SelectionState runConfigName="app">
         <option name="selectionMode" value="DROPDOWN" />
       </SelectionState>
+      <SelectionState runConfigName="MainActivity">
+        <option name="selectionMode" value="DROPDOWN" />
+      </SelectionState>
     </selectionStates>
   </component>
 </project>

app/src/main/java/ovh/smayzy/i2d_project_15_app/MainActivity.kt

@@ -1,24 +1,108 @@
 package ovh.smayzy.i2d_project_15_app
 
+import android.Manifest
+import android.bluetooth.BluetoothAdapter
+import android.bluetooth.BluetoothDevice
+import android.bluetooth.BluetoothSocket
+import android.content.pm.PackageManager
 import android.os.Bundle
 import android.util.Log
-import androidx.activity.enableEdgeToEdge
-import androidx.appcompat.app.AppCompatActivity
 import android.widget.Button
 import android.widget.Toast
-import androidx.core.view.ViewCompat
-import androidx.core.view.WindowInsetsCompat
+import androidx.activity.enableEdgeToEdge
+import androidx.appcompat.app.AppCompatActivity
+import androidx.core.app.ActivityCompat
+import java.io.IOException
+import java.util.*
 
 class MainActivity : AppCompatActivity() {
+
+    private val tag = "MainActivity"
+    private val requestEnableBt = 1
+    private val deviceName = "HC-05"
+    private val sppUuid: UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB")
+
+    private lateinit var bluetoothManager: android.bluetooth.BluetoothManager
+    private var bluetoothAdapter: BluetoothAdapter? = null
+    private var bluetoothSocket: BluetoothSocket? = null
+    private var isConnected = false
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         enableEdgeToEdge()
         setContentView(R.layout.activity_main)
 
         val connectBtn = findViewById<Button>(R.id.connect_btn)
+
+        bluetoothManager = getSystemService(BLUETOOTH_SERVICE) as android.bluetooth.BluetoothManager
+        bluetoothAdapter = bluetoothManager.adapter
+        if (bluetoothAdapter == null) {
+            Toast.makeText(this, "Bluetooth not supported by your device", Toast.LENGTH_LONG).show()
+            return
+        }
+
         connectBtn.setOnClickListener {
-            Log.i("MainActivity", "connect-btn was clicked")
-            Toast.makeText(this, getString(R.string.connected), Toast.LENGTH_SHORT).show()
+            if (isConnected) {
+                Toast.makeText(this, "Already connected", Toast.LENGTH_SHORT).show()
+                return@setOnClickListener
+            }
+
+            connectToHC05()
         }
     }
+
+    private fun connectToHC05() {
+        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.S) {
+            if (ActivityCompat.checkSelfPermission(this, Manifest.permission.BLUETOOTH_CONNECT) != PackageManager.PERMISSION_GRANTED) {
+                ActivityCompat.requestPermissions(this, arrayOf(Manifest.permission.BLUETOOTH_CONNECT), requestEnableBt)
+                return
+            }
+        } else {
+            if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
+                ActivityCompat.requestPermissions(this, arrayOf(Manifest.permission.ACCESS_FINE_LOCATION), requestEnableBt)
+            }
+        }
+
+        val pairedDevices: Set<BluetoothDevice>? = bluetoothAdapter?.bondedDevices
+        val device = pairedDevices?.find { it.name == deviceName }
+
+        if (device == null) {
+            Toast.makeText(this, "HC-05 not found, try pairing it to your phone via bluetooth", Toast.LENGTH_LONG).show()
+            return
+        }
+
+        Thread {
+            try {
+                bluetoothSocket = device.createRfcommSocketToServiceRecord(sppUuid)
+                bluetoothSocket?.connect()
+                isConnected = true
+                runOnUiThread {
+                    Toast.makeText(this, "Connected to HC-05", Toast.LENGTH_SHORT).show()
+                }
+                listenForData()
+            } catch (e: IOException) {
+                Log.e(tag, "Connection failed", e)
+                runOnUiThread {
+                    Toast.makeText(this, "Connection failed: ${e.message}", Toast.LENGTH_LONG).show()
+                }
+            }
+        }.start()
+    }
+
+    private fun listenForData() {
+        val inputStream = bluetoothSocket?.inputStream ?: return
+        val buffer = ByteArray(64)
+
+        while (true) {
+            try {
+                val bytes = inputStream.read(buffer)
+                val message = String(buffer, 0, bytes)
+                Log.i(tag, "Received: $message")
+            } catch (e: IOException) {
+                Log.e(tag, "Can't read data", e)
+                break
+            }
+        }
+    }
+
 }