car-interface-android/android/app/src/main/kotlin/com/wasp/cardash_launcher/MainActivity.kt

package com.wasp.cardash_launcher

import android.media.AudioManager
import android.view.KeyEvent
import io.flutter.embedding.android.FlutterActivity
import io.flutter.embedding.engine.FlutterEngine

class MainActivity : FlutterActivity() {
    private var launcherBridge: LauncherBridge? = null
    private var systemBridge: SystemBridge? = null

    override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
        super.configureFlutterEngine(flutterEngine)

        launcherBridge = LauncherBridge(this).also {
            it.attach(flutterEngine.dartExecutor.binaryMessenger)
        }
        systemBridge = SystemBridge(this).also {
            it.attach(flutterEngine.dartExecutor.binaryMessenger)
        }
    }

    /**
     * While the dashboard is visible, the hardware volume keys should change
     * the same media stream as the on-screen control. Without this, Android
     * falls back to the ring stream when nothing is playing and the dashboard
     * and the keys disagree.
     */
    override fun onKeyDown(keyCode: Int, event: KeyEvent?): Boolean {
        if (keyCode == KeyEvent.KEYCODE_VOLUME_UP || keyCode == KeyEvent.KEYCODE_VOLUME_DOWN) {
            adjustMediaVolume(if (keyCode == KeyEvent.KEYCODE_VOLUME_UP) 1 else -1)
            return true
        }
        return super.onKeyDown(keyCode, event)
    }

    override fun onKeyUp(keyCode: Int, event: KeyEvent?): Boolean {
        if (keyCode == KeyEvent.KEYCODE_VOLUME_UP || keyCode == KeyEvent.KEYCODE_VOLUME_DOWN) {
            return true
        }
        return super.onKeyUp(keyCode, event)
    }

    private fun adjustMediaVolume(direction: Int) {
        try {
            val audio = getSystemService(AudioManager::class.java)
            audio.adjustStreamVolume(
                AudioManager.STREAM_MUSIC,
                if (direction > 0) AudioManager.ADJUST_RAISE else AudioManager.ADJUST_LOWER,
                0,
            )
        } catch (_: Throwable) {
            // Never let a volume-key edge case take down the launcher.
        }
    }

    override fun onDestroy() {
        launcherBridge?.dispose()
        systemBridge?.dispose()
        launcherBridge = null
        systemBridge = null
        super.onDestroy()
    }
}