Android

dependencies {
    implementation("xyz.cr3dentials:zktls-sdk:1.0.0")
    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.11.0")  // for MainScope()
}

import ai.zktls.sdk.*

// Yours: what your backend returns after it creates the run.
data class IssuedRun(val packId: String, val resultUrl: String, val accessToken: String)

suspend fun treeConfig(run: IssuedRun) = TreeRunConfig(
    baseUrl = Cr3d.BASE_URL,
    appCredential = Cr3d.APP_CREDENTIAL,
    userIdHash = sha256Hex(currentUserId),                       // yours: never the raw id
    idempotencyKey = java.util.UUID.randomUUID().toString(),     // new for every run
    clientRegion = userCountry ?: "",                            // ISO 3166-1 alpha-2, or "" if unknown
    networkKey = "default",
    platformId = run.packId,
    trustBundleJson = fetchText(Cr3d.TRUST_BUNDLE_URL),          // yours: a plain HTTPS GET
    trustBundleUrl = Cr3d.TRUST_BUNDLE_URL,
    trustOperatorKey = Cr3d.TRUST_OPERATOR_KEY,
    policyBundleJson = fetchText(Cr3d.POLICY_BUNDLE_URL),
    policyBundleDigest = Cr3d.POLICY_BUNDLE_DIGEST,
    relyingPartyNonceHex = "",
    resultUrl = run.resultUrl,
    resultToken = run.accessToken,
    paramsJson = "",                                             // a check's params as JSON text, or ""
)

import ai.zktls.sdk.*
import android.app.Activity
import kotlinx.coroutines.*

class VerifyActivity : Activity() {
    private val scope = MainScope()
    private var client: ZktlsClient? = null

    fun verify(platformId: Int) {
        if (client != null) return                                   // one run at a time
        val client = ZktlsClient().also { this.client = it }         // a new client for every run
        val lifecycle = ZkTlsLifecycle(this, client.lifecycleHandle)
        client.onProgress { phase, percent ->
            runOnUiThread {
                if (phase == Phase.ATTESTING) {                      // keeps the hand-off alive if the user leaves
                    lifecycle.begin()
                    try {
                        ZkTlsSessionService.start(this@VerifyActivity, lifecycle) { client.cancel() }
                    } catch (e: IllegalStateException) {
                        // API 31+ refuses to start it from the background. The run goes on without it.
                    }
                }
                // update your progress bar
            }
        }
        scope.launch {
            try {
                val run = withContext(Dispatchers.IO) { backend.createSdkRun(platformId) }   // yours
                val summary = client.runTree(treeConfig(run), TreeWebViewHost(this@VerifyActivity, disclosure))
                when {
                    summary.handedOff -> show("You can close the app. We'll let you know when it's done.")
                    summary.succeeded && summary.delivered -> show("Verified.")
                    else -> show("Not verified. Please try again.")         // summary.error says why
                }
            } catch (e: SdkException) {
                show(message(e))                                     // see Errors; never retry automatically
            } catch (e: CancellationException) {
                throw e                                              // the activity is going: show nothing
            } catch (e: Exception) {
                show("Something went wrong. Please try again.")      // InternalException: report it
            } finally {
                lifecycle.end()                                      // every path, including failure
                ZkTlsSessionService.stop(this@VerifyActivity)
                this@VerifyActivity.client = null
            }
        }
    }

    fun cancelTapped() { client?.cancel() }

    override fun onDestroy() {
        scope.cancel()                                               // cancels the run in flight
        super.onDestroy()
    }
}

val disclosure = TreeDisclosure(
    title = "Connect your account",
    message = "We'll open the platform's own sign-in page. You sign in there yourself, and we never see " +
        "your password. Then we read the data this verification needs from your account.",
    accept = "Continue",
    decline = "Not now",
)