Gearslip/gearslip/build.gradle.kts

import java.util.Properties
import org.jetbrains.kotlin.gradle.dsl.JvmTarget
import org.jetbrains.kotlin.gradle.tasks.KotlinJvmCompile

/**
 * Gearslip: a phone-side Android Auto client built against the reverse-engineered AA wire
 * protocol, so a non-Google app can authenticate to and project onto a real car head unit
 * with no gearhead in the path. No third-party dependencies: the X.509 certificate is
 * generated by hand (see `SelfSignedCert`) so there is no BouncyCastle version to track and
 * no second crypto provider to collide with Conscrypt.
 */
plugins {
    alias(libs.plugins.android.application)
    alias(libs.plugins.kotlin.compose)
}

// The release signing key, read from an untracked keystore.properties beside this file or at the
// repository root. Third-party apps allowlist Gearslip by the SHA-256 of this certificate, so the
// key must stay the same for the life of the project - and must never be committed.
val keystoreProperties = Properties().apply {
    listOf(
        rootProject.file("keystore.properties"),
        project.file("keystore.properties"),
    ).firstOrNull { it.exists() }?.inputStream()?.use { load(it) }
}

android {
    namespace = "app.seb3thehacker.gearslip"
    compileSdk = 37

    defaultConfig {
        applicationId = "app.seb3thehacker.gearslip"
        minSdk = 31
        targetSdk = 37
        versionCode = 6
        versionName = "0.1.0-alpha"
        manifestPlaceholders["appLabel"] = "Gearslip"
    }

    signingConfigs {
        // Declared only when the properties file is present, so a clone without the key still
        // builds debug; assembleRelease then falls back to unsigned rather than failing here.
        if (keystoreProperties.getProperty("storeFile") != null) {
            create("release") {
                storeFile = rootProject.file(keystoreProperties.getProperty("storeFile"))
                storePassword = keystoreProperties.getProperty("storePassword")
                keyAlias = keystoreProperties.getProperty("keyAlias")
                keyPassword = keystoreProperties.getProperty("keyPassword")
            }
        }
    }

    buildTypes {
        release {
            signingConfig = signingConfigs.findByName("release")
        }
        // Its own package, so a dev build installs beside the release one instead of over it.
        // Signed with the release key when it's here: both builds declare the car template
        // permission, and Android refuses a second app declaring it under a different key.
        debug {
            applicationIdSuffix = ".dev"
            signingConfigs.findByName("release")?.let { signingConfig = it }
            manifestPlaceholders["appLabel"] = "Gearslip Dev"
        }
    }

    buildFeatures {
        buildConfig = true
    }

    // Keeps build output out of the module folder: <root>/build/gearslip/... instead of
    // <root>/gearslip/build/..., so everything this project produces lands under one
    // root-level build/ directory.
    layout.buildDirectory.set(rootProject.layout.buildDirectory.dir("gearslip"))

    compileOptions {
        sourceCompatibility = JavaVersion.VERSION_21
        targetCompatibility = JavaVersion.VERSION_21
    }

    defaultConfig {
        // Speech-to-text ships for 64-bit ARM only: every phone Gearslip runs on, and one copy
        // of the native library instead of four.
        ndk { abiFilters += "arm64-v8a" }
    }
    ndkVersion = "27.1.12297006"
    externalNativeBuild {
        cmake {
            path = file("src/main/cpp/CMakeLists.txt")
            version = "3.22.1"
        }
    }
    androidResources {
        // Model weights barely compress, and stored plainly they stream straight out of the APK.
        noCompress += "bin"
    }

    testOptions {
        // GearslipLog calls android.util.Log, which is a stub on the local JVM.
        unitTests.isReturnDefaultValues = true
    }

}

// Renames the produced APK and moves it to the root build/ folder (<root>/build/Gearslip-debug.apk)
// after the fact rather than fighting AGP's variant-output API across versions - simpler and
// doesn't break when that API moves again.
tasks.register("renameApk") {
    doLast {
        val rootBuildDir = rootProject.layout.buildDirectory.get().asFile
        layout.buildDirectory.dir("outputs/apk").get().asFile.walkTopDown()
            .filter { it.extension == "apk" }
            .toList()
            .forEach { apk ->
                val renamed = File(rootBuildDir, "Gearslip-${apk.parentFile.name}.apk")
                apk.copyTo(renamed, overwrite = true)
                apk.delete()
            }
    }
}
tasks.matching { it.name.startsWith("assemble") }.configureEach { finalizedBy("renameApk") }

dependencies {
    // Only for the XML window theme (Theme.Material3.DynamicColors); every screen is Compose.
    implementation(libs.google.material)
    implementation(platform(libs.androidx.compose.bom))
    implementation(libs.androidx.compose.ui)
    implementation(libs.androidx.compose.material3)
    implementation(libs.androidx.compose.material.icons.core)
    implementation(libs.androidx.activity.compose)
    implementation(libs.androidx.lifecycle.runtime.compose)
    // Used from the host side, not the app side: Gearslip renders other apps' templates rather
    // than publishing its own, so this is here for the AIDL interfaces and the model classes
    // their Bundleables deserialize into.
    implementation(libs.androidx.car.app)
    implementation(libs.androidx.car.app.projected)
    implementation(libs.androidx.media)
    testImplementation(libs.junit)
}

tasks.withType<KotlinJvmCompile>().configureEach {
    compilerOptions {
        jvmTarget.set(JvmTarget.JVM_21)
    }
}