first commit

app/.gitignore

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+/build

app/build.gradle.kts

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+plugins {
+    alias(libs.plugins.android.application)
+    alias(libs.plugins.kotlin.android)
+    alias(libs.plugins.kotlin.compose)
+}
+
+android {
+    namespace = "com.srtk.airlink"
+    compileSdk {
+        version = release(36)
+    }
+
+    defaultConfig {
+        applicationId = "com.srtk.airlink"
+        minSdk = 26
+        targetSdk = 36
+        versionCode = 1
+        versionName = "1.0"
+
+        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+    }
+
+    buildTypes {
+        release {
+            isMinifyEnabled = false
+            proguardFiles(
+                getDefaultProguardFile("proguard-android-optimize.txt"),
+                "proguard-rules.pro"
+            )
+        }
+    }
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_11
+        targetCompatibility = JavaVersion.VERSION_11
+    }
+    kotlinOptions {
+        jvmTarget = "11"
+    }
+    buildFeatures {
+        compose = true
+    }
+}
+
+dependencies {
+    implementation(libs.androidx.core.ktx)
+    implementation(libs.androidx.lifecycle.runtime.ktx)
+    implementation(libs.androidx.activity.compose)
+    implementation(platform(libs.androidx.compose.bom))
+    implementation(libs.androidx.compose.ui)
+    implementation(libs.androidx.compose.ui.graphics)
+    implementation(libs.androidx.compose.ui.tooling.preview)
+    implementation(libs.androidx.compose.material3)
+    implementation("androidx.compose.material:material-icons-extended:1.7.8")
+    testImplementation(libs.junit)
+    androidTestImplementation(libs.androidx.junit)
+    androidTestImplementation(libs.androidx.espresso.core)
+    androidTestImplementation(platform(libs.androidx.compose.bom))
+    androidTestImplementation(libs.androidx.compose.ui.test.junit4)
+    debugImplementation(libs.androidx.compose.ui.tooling)
+    debugImplementation(libs.androidx.compose.ui.test.manifest)
+
+}

app/proguard-rules.pro

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+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile

app/src/androidTest/java/com/srtk/airlink/ExampleInstrumentedTest.kt

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+package com.srtk.airlink
+
+import androidx.test.platform.app.InstrumentationRegistry
+import androidx.test.ext.junit.runners.AndroidJUnit4
+
+import org.junit.Test
+import org.junit.runner.RunWith
+
+import org.junit.Assert.*
+
+/**
+ * Instrumented test, which will execute on an Android device.
+ *
+ * See [testing documentation](http://d.android.com/tools/testing).
+ */
+@RunWith(AndroidJUnit4::class)
+class ExampleInstrumentedTest {
+    @Test
+    fun useAppContext() {
+        // Context of the app under test.
+        val appContext = InstrumentationRegistry.getInstrumentation().targetContext
+        assertEquals("com.srtk.webcam", appContext.packageName)
+    }
+}

app/src/main/AndroidManifest.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.CAMERA" />
+    <uses-permission android:name="android.permission.RECORD_AUDIO" />
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
+
+    <uses-feature android:name="android.hardware.camera" />
+    <uses-feature android:name="android.hardware.camera.autofocus"
+        android:required="false" />
+
+    <application
+        android:allowBackup="true"
+        android:dataExtractionRules="@xml/data_extraction_rules"
+        android:fullBackupContent="@xml/backup_rules"
+        android:icon="@mipmap/ic_launcher"
+        android:label="AirLink"
+        android:supportsRtl="true"
+        android:theme="@style/Theme.Webcam"
+        tools:targetApi="31">
+        <activity
+            android:name=".MainActivity"
+            android:exported="true"
+            android:screenOrientation="fullSensor"
+            android:configChanges="orientation|screenLayout|screenSize|smallestScreenSize"
+            android:theme="@style/Theme.Webcam">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+</manifest>

app/src/main/java/com/srtk/airlink/CameraDiagnostics.kt

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+package com.srtk.airlink
+
+import android.content.Context
+import android.hardware.camera2.*
+import android.media.MediaCodec
+import android.util.Log
+import android.util.Size
+
+object CameraDiagnostics {
+
+    fun printAllCapabilities(context: Context) {
+        val manager = context.getSystemService(Context.CAMERA_SERVICE) as CameraManager
+
+        println("\n========== CAMERA DIAGNOSTICS ==========\n")
+
+        for (cameraId in manager.cameraIdList) {
+            val characteristics = manager.getCameraCharacteristics(cameraId)
+            val facing = characteristics.get(CameraCharacteristics.LENS_FACING)
+            val facingStr = when(facing) {
+                CameraCharacteristics.LENS_FACING_BACK -> "BACK"
+                CameraCharacteristics.LENS_FACING_FRONT -> "FRONT"
+                else -> "EXTERNAL"
+            }
+
+            println("📷 Camera $cameraId ($facingStr)")
+            println("=" .repeat(50))
+
+            // Supported output sizes for MediaCodec
+            val map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP)
+            val codecSizes = map?.getOutputSizes(MediaCodec::class.java) ?: emptyArray()
+
+            println("\n🎥 Supported Video Resolutions (${codecSizes.size} total):")
+            codecSizes
+                .sortedByDescending { it.width * it.height }
+                .forEach { size ->
+                    val aspectRatio = String.format("%.2f", size.width.toFloat() / size.height)
+                    val mpx = String.format("%.1f", (size.width * size.height) / 1_000_000f)
+                    println("  • ${size.width}x${size.height} ($mpx MP, $aspectRatio:1)")
+                }
+
+            // FPS Ranges
+            val fpsRanges = characteristics.get(
+                CameraCharacteristics.CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES
+            ) ?: emptyArray()
+
+            println("\n📊 Supported FPS Ranges:")
+            fpsRanges.forEach { range ->
+                println("  • ${range.lower}-${range.upper} fps")
+            }
+
+            // Max digital zoom
+            val maxZoom = characteristics.get(
+                CameraCharacteristics.SCALER_AVAILABLE_MAX_DIGITAL_ZOOM
+            ) ?: 1f
+            println("\n🔍 Max Zoom: ${maxZoom}x")
+
+            // Flash
+            val hasFlash = characteristics.get(
+                CameraCharacteristics.FLASH_INFO_AVAILABLE
+            ) == true
+            println("⚡ Flash: ${if(hasFlash) "Yes" else "No"}")
+
+            // Stabilization
+            val stabilizationModes = characteristics.get(
+                CameraCharacteristics.CONTROL_AVAILABLE_VIDEO_STABILIZATION_MODES
+            ) ?: intArrayOf()
+            val hasStab = CameraMetadata.CONTROL_VIDEO_STABILIZATION_MODE_ON in stabilizationModes
+            println("📹 Video Stabilization: ${if(hasStab) "Yes" else "No"}")
+
+            // Manual focus
+            val minFocusDist = characteristics.get(
+                CameraCharacteristics.LENS_INFO_MINIMUM_FOCUS_DISTANCE
+            ) ?: 0f
+            println("🎯 Manual Focus: ${if(minFocusDist > 0) "Yes" else "No"}")
+
+            // Effects
+            val effects = characteristics.get(
+                CameraCharacteristics.CONTROL_AVAILABLE_EFFECTS
+            ) ?: intArrayOf()
+            println("\n🎨 Supported Effects:")
+            effects.forEach { effect ->
+                val name = when(effect) {
+                    CameraMetadata.CONTROL_EFFECT_MODE_OFF -> "None"
+                    CameraMetadata.CONTROL_EFFECT_MODE_MONO -> "Mono"
+                    CameraMetadata.CONTROL_EFFECT_MODE_NEGATIVE -> "Negative"
+                    CameraMetadata.CONTROL_EFFECT_MODE_SEPIA -> "Sepia"
+                    CameraMetadata.CONTROL_EFFECT_MODE_AQUA -> "Aqua"
+                    else -> "Unknown($effect)"
+                }
+                println("  • $name")
+            }
+
+            // White Balance
+            val wbModes = characteristics.get(
+                CameraCharacteristics.CONTROL_AWB_AVAILABLE_MODES
+            ) ?: intArrayOf()
+            println("\n☀️ Supported White Balance:")
+            wbModes.forEach { mode ->
+                val name = when(mode) {
+                    CameraMetadata.CONTROL_AWB_MODE_AUTO -> "Auto"
+                    CameraMetadata.CONTROL_AWB_MODE_DAYLIGHT -> "Daylight"
+                    CameraMetadata.CONTROL_AWB_MODE_CLOUDY_DAYLIGHT -> "Cloudy"
+                    CameraMetadata.CONTROL_AWB_MODE_INCANDESCENT -> "Warm"
+                    CameraMetadata.CONTROL_AWB_MODE_FLUORESCENT -> "Cool"
+                    CameraMetadata.CONTROL_AWB_MODE_SHADE -> "Shade"
+                    else -> "Unknown($mode)"
+                }
+                println("  • $name")
+            }
+
+            println("\n" + "=".repeat(50) + "\n")
+        }
+    }
+}

app/src/main/java/com/srtk/airlink/CameraStreamer.kt

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+package com.srtk.airlink
+
+import android.annotation.SuppressLint
+import android.content.Context
+import android.hardware.camera2.*
+import android.media.MediaCodec
+import android.media.MediaCodecInfo
+import android.media.MediaFormat
+import android.os.Bundle
+import android.os.Handler
+import android.os.HandlerThread
+import android.util.Log
+import android.util.Range
+import android.view.Surface
+import java.net.DatagramPacket
+import java.net.DatagramSocket
+import java.net.InetAddress
+import java.util.concurrent.Semaphore
+import java.util.concurrent.TimeUnit
+import kotlin.math.abs
+import kotlin.math.min
+
+data class VideoConfig(val width: Int, val height: Int, val fps: Int) {
+    override fun toString() = "${height}p"
+    fun toDetailedString() = "${height}p (${width}×${height} @ ${fps}fps)"
+}
+
+data class CameraCapabilities(
+    val supportedConfigs: List<VideoConfig>,
+    val maxZoom: Float,
+    val hasFlash: Boolean,
+    val hasFrontCamera: Boolean,
+    val supportedWhiteBalance: List<WhiteBalance>,
+    val focusRange: Range<Float>?,
+    val exposureRange: Range<Int>?
+)
+
+enum class WhiteBalance(val value: Int, val label: String) {
+    AUTO(CameraMetadata.CONTROL_AWB_MODE_AUTO, "Auto"),
+    WARM(CameraMetadata.CONTROL_AWB_MODE_INCANDESCENT, "Warm"),
+    COOL(CameraMetadata.CONTROL_AWB_MODE_FLUORESCENT, "Cool")
+}
+
+class CameraStreamer(private val context: Context) {
+    private val TAG = "CameraStreamer"
+    private val manager = context.getSystemService(Context.CAMERA_SERVICE) as CameraManager
+
+    private val cameraThread = HandlerThread("CamThread").apply { start() }
+    private val camHandler = Handler(cameraThread.looper)
+
+    private var cameraDevice: CameraDevice? = null
+    private var captureSession: CameraCaptureSession? = null
+    private var requestBuilder: CaptureRequest.Builder? = null
+    private var mediaCodec: MediaCodec? = null
+    private var socket: DatagramSocket? = null
+
+    @Volatile private var isStreaming = false
+    private val restartLock = Semaphore(1)
+    private var currentConfig = VideoConfig(960, 720, 30)
+    private var bitrate = 3000000
+
+    private var zoomRatio = 1f
+    private var flashMode = false
+    private var wbMode = CameraMetadata.CONTROL_AWB_MODE_AUTO
+    private var focusMode = CameraMetadata.CONTROL_AF_MODE_CONTINUOUS_VIDEO
+    private var focusDistance = 0f
+    private var exposureCompensation = 0
+    private var onErrorCallback: ((String) -> Unit)? = null
+    private var onDisconnectedCallback: (() -> Unit)? = null
+
+    private var lastPacketTime = 0L
+    private val connectionTimeout = 5000L // 5 seconds
+
+    fun setErrorCallback(callback: (String) -> Unit) {
+        onErrorCallback = callback
+    }
+
+    fun setDisconnectedCallback(callback: () -> Unit) {
+        onDisconnectedCallback = callback
+    }
+
+    // Test if a resolution actually works with the encoder
+    private fun testEncoderResolution(width: Int, height: Int): Boolean {
+        var testCodec: MediaCodec? = null
+        try {
+            val format = MediaFormat.createVideoFormat(
+                MediaFormat.MIMETYPE_VIDEO_AVC,
+                width,
+                height
+            ).apply {
+                setInteger(
+                    MediaFormat.KEY_COLOR_FORMAT,
+                    MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface
+                )
+                setInteger(MediaFormat.KEY_BIT_RATE, 2000000)
+                setInteger(MediaFormat.KEY_FRAME_RATE, 30)
+                setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 2)
+            }
+
+            testCodec = MediaCodec.createEncoderByType(MediaFormat.MIMETYPE_VIDEO_AVC)
+            testCodec.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE)
+            testCodec.release()
+
+            Log.d(TAG, "✅ Resolution ${width}x${height} WORKS")
+            return true
+        } catch (e: Exception) {
+            Log.d(TAG, "❌ Resolution ${width}x${height} FAILED: ${e.message}")
+            return false
+        } finally {
+            try {
+                testCodec?.release()
+            } catch (e: Exception) {}
+        }
+    }
+
+    private fun is16by9(width: Int, height: Int): Boolean {
+        val ratio = width.toDouble() / height.toDouble()
+        return abs(ratio - 16.0 / 9.0) < 0.1
+    }
+
+    private fun is4by3(width: Int, height: Int): Boolean {
+        val ratio = width.toDouble() / height.toDouble()
+        return abs(ratio - 4.0 / 3.0) < 0.1
+    }
+
+    fun getCameraCapabilities(useFront: Boolean): CameraCapabilities {
+        val camId = getCameraId(useFront)
+        val chars = manager.getCameraCharacteristics(camId)
+        val map = chars.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP)!!
+
+        val allSizes = map.getOutputSizes(MediaCodec::class.java)
+            .filter { is16by9(it.width, it.height) || is4by3(it.width, it.height) }
+            .sortedByDescending { it.width * it.height }
+
+        Log.d(TAG, "Testing encoder capabilities...")
+
+        val configs = mutableListOf<VideoConfig>()
+        val fpsRanges = chars.get(
+            CameraCharacteristics.CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES
+        ) ?: emptyArray()
+
+        for (size in allSizes) {
+            try {
+                // TEST if encoder actually supports this resolution
+                if (!testEncoderResolution(size.width, size.height)) {
+                    continue
+                }
+
+                val minFrameDuration = map.getOutputMinFrameDuration(
+                    MediaCodec::class.java,
+                    size
+                )
+
+                if (minFrameDuration <= 0) continue
+
+                val maxFpsFromDuration = (1_000_000_000.0 / minFrameDuration).toInt()
+                val validRanges = fpsRanges.filter {
+                    it.upper <= maxFpsFromDuration && it.upper >= 15
+                }
+
+                val targetFps = min(validRanges.maxOfOrNull { it.upper } ?: 30, 30)
+
+                if (targetFps >= 15) {
+                    configs.add(VideoConfig(size.width, size.height, targetFps))
+                }
+            } catch (e: Exception) {
+                Log.w(TAG, "Skipping ${size.width}x${size.height}: ${e.message}")
+            }
+        }
+
+        if (configs.isEmpty()) {
+            configs.add(VideoConfig(640, 480, 30))
+            Log.w(TAG, "No configs found, added 640x480 fallback")
+        }
+
+        val maxZoom = chars.get(CameraCharacteristics.SCALER_AVAILABLE_MAX_DIGITAL_ZOOM) ?: 1f
+        val hasFlash = chars.get(CameraCharacteristics.FLASH_INFO_AVAILABLE) == true
+        val hasFront = manager.cameraIdList.any {
+            manager.getCameraCharacteristics(it).get(CameraCharacteristics.LENS_FACING) ==
+                    CameraCharacteristics.LENS_FACING_FRONT
+        }
+
+        val minFocus = chars.get(CameraCharacteristics.LENS_INFO_MINIMUM_FOCUS_DISTANCE)
+        val exposureRange = chars.get(CameraCharacteristics.CONTROL_AE_COMPENSATION_RANGE)
+
+        return CameraCapabilities(
+            configs.sortedByDescending { it.width * it.height },
+            maxZoom,
+            hasFlash,
+            hasFront,
+            listOf(WhiteBalance.AUTO, WhiteBalance.WARM, WhiteBalance.COOL),
+            if (minFocus != null && minFocus > 0) Range(0f, minFocus) else null,
+            exposureRange
+        )
+    }
+
+    fun start(
+        ip: InetAddress,
+        port: Int,
+        config: VideoConfig,
+        useFront: Boolean
+    ) {
+        currentConfig = config
+        val camId = getCameraId(useFront)
+
+        camHandler.post {
+            try {
+                if (restartLock.tryAcquire(3, TimeUnit.SECONDS)) {
+                    try {
+                        stopInternal()
+                        Thread.sleep(500)
+                        startInternal(ip, port, camId)
+                    } finally {
+                        restartLock.release()
+                    }
+                }
+            } catch (e: Exception) {
+                Log.e(TAG, "Start error", e)
+                onErrorCallback?.invoke("Failed to start: ${e.message}")
+            }
+        }
+    }
+
+    fun updateBitrate(mbps: Int) {
+        val newBitrate = mbps * 1_000_000
+        if (bitrate == newBitrate) return
+
+        bitrate = newBitrate
+
+        camHandler.post {
+            try {
+                mediaCodec?.let { codec ->
+                    val bundle = Bundle().apply {
+                        putInt(MediaCodec.PARAMETER_KEY_VIDEO_BITRATE, bitrate)
+                    }
+                    codec.setParameters(bundle)
+                    Log.d(TAG, "Bitrate updated to ${mbps} Mbps")
+                }
+            } catch (e: Exception) {
+                Log.e(TAG, "Bitrate update failed", e)
+            }
+        }
+    }
+
+    fun setZoom(z: Float) {
+        zoomRatio = z
+        updateSession()
+    }
+
+    fun setTorch(on: Boolean) {
+        flashMode = on
+        updateSession()
+    }
+
+    fun setWhiteBalance(wb: WhiteBalance) {
+        wbMode = wb.value
+        updateSession()
+    }
+
+    fun setFocusMode(auto: Boolean) {
+        focusMode = if (auto) CameraMetadata.CONTROL_AF_MODE_CONTINUOUS_VIDEO
+        else CameraMetadata.CONTROL_AF_MODE_OFF
+        updateSession()
+    }
+
+    fun setFocusDistance(distance: Float) {
+        focusDistance = distance
+        focusMode = CameraMetadata.CONTROL_AF_MODE_OFF
+        updateSession()
+    }
+
+    fun setExposure(value: Int) {
+        exposureCompensation = value
+        updateSession()
+    }
+
+    @SuppressLint("MissingPermission")
+    private fun startInternal(
+        ip: InetAddress,
+        port: Int,
+        camId: String
+    ) {
+        try {
+            socket = DatagramSocket()
+            isStreaming = true
+            lastPacketTime = System.currentTimeMillis()
+
+            val width = currentConfig.width
+            val height = currentConfig.height
+
+            val pixelCount = width * height
+            val calculatedBitrate = when {
+                pixelCount >= 1920 * 1080 -> 8_000_000
+                pixelCount >= 1280 * 720 -> 5_000_000
+                pixelCount >= 640 * 480 -> 2_500_000
+                else -> 1_500_000
+            }
+
+            Log.d(TAG, "Starting: ${width}x${height} @ ${currentConfig.fps}fps")
+
+            val format = MediaFormat.createVideoFormat(
+                MediaFormat.MIMETYPE_VIDEO_AVC,
+                width,
+                height
+            ).apply {
+                setInteger(
+                    MediaFormat.KEY_COLOR_FORMAT,
+                    MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface
+                )
+                setInteger(MediaFormat.KEY_BIT_RATE, calculatedBitrate)
+                setInteger(MediaFormat.KEY_FRAME_RATE, currentConfig.fps)
+                setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 2)
+            }
+
+            mediaCodec = MediaCodec.createEncoderByType(MediaFormat.MIMETYPE_VIDEO_AVC)
+            mediaCodec?.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE)
+
+            val surface = mediaCodec?.createInputSurface()
+                ?: throw Exception("Failed to create input surface")
+
+            mediaCodec?.start()
+
+            Log.d(TAG, "✅ Encoder started with ${width}x${height}")
+
+            // Start connection monitor
+            Thread {
+                while (isStreaming) {
+                    Thread.sleep(1000)
+                    if (System.currentTimeMillis() - lastPacketTime > connectionTimeout) {
+                        Log.w(TAG, "Server disconnected - no data sent")
+                        stop()
+                        onDisconnectedCallback?.invoke()
+                        break
+                    }
+                }
+            }.start()
+
+            Thread {
+                Thread.currentThread().priority = Thread.MAX_PRIORITY
+                streamLoop(ip, port)
+            }.start()
+
+            manager.openCamera(
+                camId,
+                object : CameraDevice.StateCallback() {
+                    override fun onOpened(camera: CameraDevice) {
+                        cameraDevice = camera
+                        createSession(camera, surface)
+                    }
+
+                    override fun onDisconnected(camera: CameraDevice) {
+                        Log.w(TAG, "Camera disconnected")
+                        stopInternal()
+                    }
+
+                    override fun onError(camera: CameraDevice, error: Int) {
+                        Log.e(TAG, "Camera error: $error")
+                        stopInternal()
+                        onErrorCallback?.invoke("Camera error: $error")
+                    }
+                },
+                camHandler
+            )
+        } catch (e: Exception) {
+            Log.e(TAG, "Start failed: ${e.message}", e)
+            onErrorCallback?.invoke("Failed to start: ${e.message}")
+            stopInternal()
+        }
+    }
+
+    private fun createSession(camera: CameraDevice, surface: Surface) {
+        try {
+            camera.createCaptureSession(
+                listOf(surface),
+                object : CameraCaptureSession.StateCallback() {
+                    override fun onConfigured(session: CameraCaptureSession) {
+                        if (!isStreaming) return
+
+                        captureSession = session
+                        requestBuilder = camera.createCaptureRequest(
+                            CameraDevice.TEMPLATE_RECORD
+                        ).apply {
+                            addTarget(surface)
+                            set(CaptureRequest.CONTROL_MODE, CameraMetadata.CONTROL_MODE_AUTO)
+                            set(CaptureRequest.CONTROL_AE_MODE, CameraMetadata.CONTROL_AE_MODE_ON)
+                            set(CaptureRequest.CONTROL_AE_TARGET_FPS_RANGE,
+                                Range(currentConfig.fps, currentConfig.fps))
+                            set(CaptureRequest.CONTROL_AF_MODE, focusMode)
+                            set(CaptureRequest.CONTROL_VIDEO_STABILIZATION_MODE,
+                                CameraMetadata.CONTROL_VIDEO_STABILIZATION_MODE_ON)
+
+                            if (focusMode == CameraMetadata.CONTROL_AF_MODE_OFF) {
+                                set(CaptureRequest.LENS_FOCUS_DISTANCE, focusDistance)
+                            }
+                            set(CaptureRequest.CONTROL_AE_EXPOSURE_COMPENSATION, exposureCompensation)
+                        }
+                        updateSession()
+                        Log.d(TAG, "Camera session started")
+                    }
+
+                    override fun onConfigureFailed(session: CameraCaptureSession) {
+                        Log.e(TAG, "Session config failed")
+                        onErrorCallback?.invoke("Camera session failed")
+                    }
+                },
+                camHandler
+            )
+        } catch (e: Exception) {
+            Log.e(TAG, "Create session error", e)
+        }
+    }
+
+    private fun updateSession() {
+        val builder = requestBuilder ?: return
+        val session = captureSession ?: return
+        try {
+            if (zoomRatio > 1f) {
+                builder.set(CaptureRequest.CONTROL_ZOOM_RATIO, zoomRatio)
+            }
+            builder.set(
+                CaptureRequest.FLASH_MODE,
+                if (flashMode) CameraMetadata.FLASH_MODE_TORCH
+                else CameraMetadata.FLASH_MODE_OFF
+            )
+            builder.set(CaptureRequest.CONTROL_AWB_MODE, wbMode)
+            builder.set(CaptureRequest.CONTROL_AF_MODE, focusMode)
+
+            if (focusMode == CameraMetadata.CONTROL_AF_MODE_OFF) {
+                builder.set(CaptureRequest.LENS_FOCUS_DISTANCE, focusDistance)
+            }
+
+            builder.set(CaptureRequest.CONTROL_AE_EXPOSURE_COMPENSATION, exposureCompensation)
+
+            session.setRepeatingRequest(builder.build(), null, camHandler)
+        } catch (e: Exception) {
+            Log.e(TAG, "Update session error", e)
+        }
+    }
+
+    private fun streamLoop(ip: InetAddress, port: Int) {
+        val bufferInfo = MediaCodec.BufferInfo()
+        val maxChunkSize = 1400
+
+        Log.d(TAG, "Stream loop started")
+
+        try {
+            while (isStreaming) {
+                val codec = mediaCodec ?: break
+
+                val index = codec.dequeueOutputBuffer(bufferInfo, 10000)
+
+                when (index) {
+                    MediaCodec.INFO_OUTPUT_FORMAT_CHANGED -> {
+                        val format = codec.outputFormat
+                        Log.d(TAG, "Output format: $format")
+                    }
+
+                    in 0..Int.MAX_VALUE -> {
+                        try {
+                            if (bufferInfo.size <= 0) {
+                                codec.releaseOutputBuffer(index, false)
+                                continue
+                            }
+
+                            val buffer = codec.getOutputBuffer(index) ?: continue
+                            buffer.position(bufferInfo.offset)
+                            buffer.limit(bufferInfo.offset + bufferInfo.size)
+
+                            val frameData = ByteArray(bufferInfo.size)
+                            buffer.get(frameData)
+
+                            var offset = 0
+                            while (offset < frameData.size && isStreaming) {
+                                val chunkSize = min(maxChunkSize, frameData.size - offset)
+                                socket?.send(
+                                    DatagramPacket(frameData, offset, chunkSize, ip, port)
+                                )
+                                offset += chunkSize
+                            }
+
+                            lastPacketTime = System.currentTimeMillis()
+                            codec.releaseOutputBuffer(index, false)
+                        } catch (e: Exception) {
+                            Log.e(TAG, "Buffer processing error", e)
+                        }
+                    }
+                }
+            }
+        } catch (e: Exception) {
+            Log.e(TAG, "Stream loop error", e)
+        }
+
+        Log.d(TAG, "Stream loop ended")
+    }
+
+    fun stop() {
+        camHandler.post { stopInternal() }
+    }
+
+    fun cleanup() {
+        stop()
+        cameraThread.quitSafely()
+    }
+
+    private fun stopInternal() {
+        isStreaming = false
+        try {
+            captureSession?.stopRepeating()
+            captureSession?.close()
+            captureSession = null
+        } catch (e: Exception) {
+            Log.e(TAG, "Session stop error", e)
+        }
+
+        try {
+            cameraDevice?.close()
+            cameraDevice = null
+        } catch (e: Exception) {
+            Log.e(TAG, "Camera close error", e)
+        }
+
+        try {
+            mediaCodec?.stop()
+            mediaCodec?.release()
+            mediaCodec = null
+        } catch (e: Exception) {
+            Log.e(TAG, "Codec stop error", e)
+        }
+
+        try {
+            socket?.close()
+            socket = null
+        } catch (e: Exception) {
+            Log.e(TAG, "Socket close error", e)
+        }
+
+        requestBuilder = null
+    }
+
+    private fun getCameraId(front: Boolean): String {
+        val target = if (front)
+            CameraCharacteristics.LENS_FACING_FRONT
+        else
+            CameraCharacteristics.LENS_FACING_BACK
+        return manager.cameraIdList.firstOrNull {
+            manager.getCameraCharacteristics(it)
+                .get(CameraCharacteristics.LENS_FACING) == target
+        } ?: manager.cameraIdList[0]
+    }
+}

app/src/main/java/com/srtk/airlink/NetworkDiscovery.kt

@@ -0,0 +1,125 @@
+package com.srtk.airlink
+
+import android.content.Context
+import android.net.nsd.NsdManager
+import android.net.nsd.NsdServiceInfo
+import android.util.Log
+import kotlinx.coroutines.channels.awaitClose
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.callbackFlow
+import java.net.InetAddress
+
+data class ServerInfo(
+    val name: String,
+    val ip: InetAddress,
+    val port: Int
+) {
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (other !is ServerInfo) return false
+        return ip == other.ip && port == other.port
+    }
+
+    override fun hashCode(): Int {
+        return 31 * ip.hashCode() + port
+    }
+}
+
+class DiscoveryManager(context: Context) {
+    private val TAG = "DiscoveryManager"
+    private val nsdManager = context.getSystemService(
+        Context.NSD_SERVICE
+    ) as NsdManager
+    private val SERVICE_TYPE = "_procam._udp."
+
+    fun discover(): Flow<ServerInfo> = callbackFlow {
+        val discoveryListener = object : NsdManager.DiscoveryListener {
+            override fun onDiscoveryStarted(regType: String) {
+                Log.d(TAG, "Discovery started")
+            }
+
+            override fun onServiceFound(service: NsdServiceInfo) {
+                if (service.serviceType.contains("_procam")) {
+                    try {
+                        nsdManager.resolveService(
+                            service,
+                            object : NsdManager.ResolveListener {
+                                override fun onResolveFailed(
+                                    serviceInfo: NsdServiceInfo,
+                                    errorCode: Int
+                                ) {
+                                    Log.w(TAG, "Resolve failed: $errorCode")
+                                }
+
+                                override fun onServiceResolved(
+                                    serviceInfo: NsdServiceInfo
+                                ) {
+                                    try {
+                                        val server = ServerInfo(
+                                            name = serviceInfo.serviceName,
+                                            ip = serviceInfo.host,
+                                            port = serviceInfo.port
+                                        )
+                                        trySend(server)
+                                    } catch (e: Exception) {
+                                        Log.e(
+                                            TAG,
+                                            "Error creating ServerInfo: ${e.message}"
+                                        )
+                                    }
+                                }
+                            }
+                        )
+                    } catch (e: Exception) {
+                        Log.e(TAG, "Resolve error: ${e.message}")
+                    }
+                }
+            }
+
+            override fun onServiceLost(service: NsdServiceInfo) {
+                Log.d(TAG, "Service lost: ${service.serviceName}")
+            }
+
+            override fun onDiscoveryStopped(serviceType: String) {
+                Log.d(TAG, "Discovery stopped")
+            }
+
+            override fun onStartDiscoveryFailed(
+                serviceType: String,
+                errorCode: Int
+            ) {
+                Log.e(TAG, "Start discovery failed: $errorCode")
+                try {
+                    nsdManager.stopServiceDiscovery(this)
+                } catch (e: Exception) {
+                    Log.e(TAG, "Stop discovery error: ${e.message}")
+                }
+            }
+
+            override fun onStopDiscoveryFailed(
+                serviceType: String,
+                errorCode: Int
+            ) {
+                Log.e(TAG, "Stop discovery failed: $errorCode")
+            }
+        }
+
+        try {
+            nsdManager.discoverServices(
+                SERVICE_TYPE,
+                NsdManager.PROTOCOL_DNS_SD,
+                discoveryListener
+            )
+        } catch (e: Exception) {
+            Log.e(TAG, "Discovery start error: ${e.message}")
+        }
+
+        awaitClose {
+            try {
+                nsdManager.stopServiceDiscovery(discoveryListener)
+            } catch (e: Exception) {
+                Log.e(TAG, "Discovery cleanup error: ${e.message}")
+            }
+        }
+    }
+}

app/src/main/java/com/srtk/airlink/ui/theme/Color.kt

@@ -0,0 +1,11 @@
+package com.srtk.airlink.ui.theme
+
+import androidx.compose.ui.graphics.Color
+
+val Purple80 = Color(0xFFD0BCFF)
+val PurpleGrey80 = Color(0xFFCCC2DC)
+val Pink80 = Color(0xFFEFB8C8)
+
+val Purple40 = Color(0xFF6650a4)
+val PurpleGrey40 = Color(0xFF625b71)
+val Pink40 = Color(0xFF7D5260)

app/src/main/java/com/srtk/airlink/ui/theme/Theme.kt

@@ -0,0 +1,57 @@
+package com.srtk.airlink.ui.theme
+
+import android.os.Build
+import androidx.compose.foundation.isSystemInDarkTheme
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.darkColorScheme
+import androidx.compose.material3.dynamicDarkColorScheme
+import androidx.compose.material3.dynamicLightColorScheme
+import androidx.compose.material3.lightColorScheme
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.platform.LocalContext
+
+private val DarkColorScheme = darkColorScheme(
+    primary = Purple80,
+    secondary = PurpleGrey80,
+    tertiary = Pink80
+)
+
+private val LightColorScheme = lightColorScheme(
+    primary = Purple40,
+    secondary = PurpleGrey40,
+    tertiary = Pink40
+
+    /* Other default colors to override
+    background = Color(0xFFFFFBFE),
+    surface = Color(0xFFFFFBFE),
+    onPrimary = Color.White,
+    onSecondary = Color.White,
+    onTertiary = Color.White,
+    onBackground = Color(0xFF1C1B1F),
+    onSurface = Color(0xFF1C1B1F),
+    */
+)
+
+@Composable
+fun WebcamTheme(
+    darkTheme: Boolean = isSystemInDarkTheme(),
+    // Dynamic color is available on Android 12+
+    dynamicColor: Boolean = true,
+    content: @Composable () -> Unit
+) {
+    val colorScheme = when {
+        dynamicColor && Build.VERSION.SDK_INT >= Build.VERSION_CODES.S -> {
+            val context = LocalContext.current
+            if (darkTheme) dynamicDarkColorScheme(context) else dynamicLightColorScheme(context)
+        }
+
+        darkTheme -> DarkColorScheme
+        else -> LightColorScheme
+    }
+
+    MaterialTheme(
+        colorScheme = colorScheme,
+        typography = Typography,
+        content = content
+    )
+}

app/src/main/java/com/srtk/airlink/ui/theme/Type.kt

@@ -0,0 +1,34 @@
+package com.srtk.airlink.ui.theme
+
+import androidx.compose.material3.Typography
+import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.text.font.FontFamily
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.sp
+
+// Set of Material typography styles to start with
+val Typography = Typography(
+    bodyLarge = TextStyle(
+        fontFamily = FontFamily.Default,
+        fontWeight = FontWeight.Normal,
+        fontSize = 16.sp,
+        lineHeight = 24.sp,
+        letterSpacing = 0.5.sp
+    )
+    /* Other default text styles to override
+    titleLarge = TextStyle(
+        fontFamily = FontFamily.Default,
+        fontWeight = FontWeight.Normal,
+        fontSize = 22.sp,
+        lineHeight = 28.sp,
+        letterSpacing = 0.sp
+    ),
+    labelSmall = TextStyle(
+        fontFamily = FontFamily.Default,
+        fontWeight = FontWeight.Medium,
+        fontSize = 11.sp,
+        lineHeight = 16.sp,
+        letterSpacing = 0.5.sp
+    )
+    */
+)

app/src/main/res/drawable/ic_launcher_background.xml

@@ -0,0 +1,74 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector
+    android:height="108dp"
+    android:width="108dp"
+    android:viewportHeight="108"
+    android:viewportWidth="108"
+    xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="#3DDC84"
+          android:pathData="M0,0h108v108h-108z"/>
+    <path android:fillColor="#00000000" android:pathData="M9,0L9,108"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M19,0L19,108"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M29,0L29,108"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M39,0L39,108"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M49,0L49,108"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M59,0L59,108"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M69,0L69,108"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M79,0L79,108"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M89,0L89,108"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M99,0L99,108"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M0,9L108,9"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M0,19L108,19"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M0,29L108,29"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M0,39L108,39"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M0,49L108,49"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M0,59L108,59"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M0,69L108,69"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M0,79L108,79"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M0,89L108,89"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M0,99L108,99"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M19,29L89,29"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M19,39L89,39"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M19,49L89,49"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M19,59L89,59"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M19,69L89,69"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M19,79L89,79"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M29,19L29,89"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M39,19L39,89"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M49,19L49,89"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M59,19L59,89"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M69,19L69,89"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+    <path android:fillColor="#00000000" android:pathData="M79,19L79,89"
+          android:strokeColor="#33FFFFFF" android:strokeWidth="0.8"/>
+</vector>

app/src/main/res/drawable/ic_launcher_foreground.xml

@@ -0,0 +1,30 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path android:pathData="M31,63.928c0,0 6.4,-11 12.1,-13.1c7.2,-2.6 26,-1.4 26,-1.4l38.1,38.1L107,108.928l-32,-1L31,63.928z">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:endX="85.84757"
+                android:endY="92.4963"
+                android:startX="42.9492"
+                android:startY="49.59793"
+                android:type="linear">
+                <item
+                    android:color="#44000000"
+                    android:offset="0.0" />
+                <item
+                    android:color="#00000000"
+                    android:offset="1.0" />
+            </gradient>
+        </aapt:attr>
+    </path>
+    <path
+        android:fillColor="#FFFFFF"
+        android:fillType="nonZero"
+        android:pathData="M65.3,45.828l3.8,-6.6c0.2,-0.4 0.1,-0.9 -0.3,-1.1c-0.4,-0.2 -0.9,-0.1 -1.1,0.3l-3.9,6.7c-6.3,-2.8 -13.4,-2.8 -19.7,0l-3.9,-6.7c-0.2,-0.4 -0.7,-0.5 -1.1,-0.3C38.8,38.328 38.7,38.828 38.9,39.228l3.8,6.6C36.2,49.428 31.7,56.028 31,63.928h46C76.3,56.028 71.8,49.428 65.3,45.828zM43.4,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2c-0.3,-0.7 -0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C45.3,56.528 44.5,57.328 43.4,57.328L43.4,57.328zM64.6,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2s-0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C66.5,56.528 65.6,57.328 64.6,57.328L64.6,57.328z"
+        android:strokeWidth="1"
+        android:strokeColor="#00000000" />
+</vector>

app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background"/>
+    <foreground android:drawable="@mipmap/ic_launcher_foreground"/>
+</adaptive-icon>

app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background"/>
+    <foreground android:drawable="@mipmap/ic_launcher_foreground"/>
+</adaptive-icon>

app/src/main/res/values/colors.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="purple_200">#FFBB86FC</color>
+    <color name="purple_500">#FF6200EE</color>
+    <color name="purple_700">#FF3700B3</color>
+    <color name="teal_200">#FF03DAC5</color>
+    <color name="teal_700">#FF018786</color>
+    <color name="black">#FF000000</color>
+    <color name="white">#FFFFFFFF</color>
+</resources>

app/src/main/res/values/strings.xml

@@ -0,0 +1,3 @@
+<resources>
+    <string name="app_name">webcam</string>
+</resources>

app/src/main/res/values/themes.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+
+    <style name="Theme.Webcam" parent="android:Theme.Material.Light.NoActionBar" />
+</resources>

app/src/main/res/xml/backup_rules.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample backup rules file; uncomment and customize as necessary.
+   See https://developer.android.com/guide/topics/data/autobackup
+   for details.
+   Note: This file is ignored for devices older than API 31
+   See https://developer.android.com/about/versions/12/backup-restore
+-->
+<full-backup-content>
+    <!--
+   <include domain="sharedpref" path="."/>
+   <exclude domain="sharedpref" path="device.xml"/>
+-->
+</full-backup-content>

app/src/main/res/xml/data_extraction_rules.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample data extraction rules file; uncomment and customize as necessary.
+   See https://developer.android.com/about/versions/12/backup-restore#xml-changes
+   for details.
+-->
+<data-extraction-rules>
+    <cloud-backup>
+        <!-- TODO: Use <include> and <exclude> to control what is backed up.
+        <include .../>
+        <exclude .../>
+        -->
+    </cloud-backup>
+    <!--
+    <device-transfer>
+        <include .../>
+        <exclude .../>
+    </device-transfer>
+    -->
+</data-extraction-rules>

app/src/test/java/com/srtk/airlink/ExampleUnitTest.kt

@@ -0,0 +1,17 @@
+package com.srtk.airlink
+
+import org.junit.Test
+
+import org.junit.Assert.*
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * See [testing documentation](http://d.android.com/tools/testing).
+ */
+class ExampleUnitTest {
+    @Test
+    fun addition_isCorrect() {
+        assertEquals(4, 2 + 2)
+    }
+}