// Nothing Gradle builds here may land on another checkout's emulator.
//
// Android's install, uninstall and connected-test tasks talk to the adb
// server directly and act on *every* attached device -- the wrapper `adb` in
// this repo never sees them, so none of its aiming applies. With two
// sessions' emulators up, `./gradlew installDebug` replaces the app on both,
// reports success, and says nothing; from the other session that reads as
// its own build never landing. It happened on 2026-08-31.
//
// This is an init script, applied to every build on this machine, rather
// than something each project opts into: a rule a checkout has to adopt is
// one the next checkout will not have, and the sessions this protects are
// working in checkouts nobody has visited yet.
//
// The decision itself is `emu check` (one rule for "which device does a
// command here mean", shared with the adb wrapper), run in the project's own
// directory because that is what names the AVD. It refuses only when another
// checkout's emulator is attached; EMU_ANY_DEVICE=1 means every device
// anyway.

def emu = new File(System.getProperty("user.home"), ".local/bin/emu").absolutePath

gradle.allprojects { project ->
    def workingDir = project.rootDir
    project.tasks.configureEach { task ->
        // Matched on where the task class comes from as well as on its name:
        // a build of any kind may have an `install`, and this must not fail
        // a project that has nothing to do with a device.
        if (!task.getClass().name.startsWith('com.android.')) return
        if (!(task.name =~ /^(install|uninstall|connected)/)) return

        task.doFirst {
            def said
            def status
            try {
                def process = new ProcessBuilder(emu, 'check')
                        .directory(workingDir)
                        .redirectErrorStream(true)
                        .start()
                said = process.inputStream.getText('UTF-8')
                status = process.waitFor()
            } catch (IOException e) {
                // Failing closed: this script is installed by
                // emulator-tools, so `emu` missing means a half-installation
                // rather than a machine that never had the guard.
                throw new org.gradle.api.GradleException(
                        "\ncannot check which emulator this build means: ${emu} is not runnable" +
                        "\n  run ~/repos/emulator-tools/install.sh, or set EMU_ANY_DEVICE=1")
            }
            if (status != 0) {
                throw new org.gradle.api.GradleException('\n' + said.trim())
            }
        }
    }
}