flame-harness-admob

flame-harness-admob

Phase 7 of the flutter-flame-harness pipeline. Analyzes the game's loop, decides where rewarded ads fit naturally, guides the user through manual ad-unit creation in the AdMob console, then injects google_mobile_ads, iOS ATT, and UMP consent code.

All file schemas (config.md, state.md, pipeline-log.md) and the phase transition table are defined in docs/harness-protocol.md — that document is the single source of truth (§1 for config.md including the admob: block; §2 for state.md; §6 for log schemas; §7 for the admob → build transition and the skip_admob branch rule). Do not redefine schemas here.

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Input — Read Inputs

Before any action, load:

1. docs/harness/config.md — extract app_slug, app_name, and skip_admob (bool).
2. docs/harness/state.md — confirm next_role: admob.
3. PRD at docs/harness/prd.md — read the game loop, monetization intent, and any explicit ad placement requests.

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Skip Flag — skip_admob Handling

Check skip_admob from docs/harness/config.md immediately after loading inputs.

If skip_admob: true:

1. Write docs/harness/config.md with admob.enabled: false (per protocol §1 admob: block).

2. Write docs/harness/state.md with:

   status: running
   current_phase: admob
   next_role: build
   updated_at: "<ISO-8601 UTC now>"
   

3. Append to docs/harness/pipeline-log.md (per protocol §6):

   | <ISO-8601 UTC now> | complete | admob | skip_admob=true; AdMob skipped; next: build |
   

4. Exit immediately. Do not ask questions, do not inject code.

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Strategy — Rewarded Ad Placement

Read the PRD and game loop carefully. The goal is rewarded ads that feel like a natural reward mechanic, not an interruption.

Rewarded Ad Placement Principles

• Revive / continue: Offer a rewarded ad when the player dies or fails — "Watch an ad to continue?". This is the highest-converting rewarded placement for Flame games.
• Double coins / bonus: After a session ends, offer a rewarded ad to double the score or coins earned.
• Extra life / shield: Mid-game offer for an extra life when health is critical.
• Unlock hint / skip: In puzzle games, offer a rewarded ad to reveal a hint or skip a level.

Choose placements that match the PRD's described game loop. Document the chosen placements explicitly — a fresh Claude running flame-harness-generator must know exactly where to add the RewardedAdHelper.show() call.

No Intrusive Interstitials

Do not add interstitial ads unless the PRD explicitly requests them. Interstitials between levels or at session start hurt retention and risk App Store policy violations. Rewarded ads are opt-in and always preferred.

Banner Ads (conditional)

Add a banner ad only if the PRD explicitly requests one. If a banner is used, apply the SafeArea banner gap pattern: wrap the game canvas in a Column with a SafeArea-padded BannerAdWidget at the bottom so the ad never overlaps game content.

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Manual Unit Creation — AdMob Console

Google's API cannot create AdMob ad units programmatically. The user must create them manually in the AdMob console. Follow these steps:

Step 1 — Collect App IDs

Use AskUserQuestion to ask the user:

"Please open the AdMob console (https://admob.google.com) and:

1. Add your iOS app → copy the iOS App ID (format: ca-app-pub-XXXX~YYYY).
2. Add your Android app → copy the Android App ID (format: ca-app-pub-XXXX~ZZZZ).

Paste both IDs here. If you haven't done this yet, type 'defer' and I'll pause."

If the user types defer or says they haven't done it yet, write docs/harness/state.md with:

status: paused
current_phase: admob
next_role: admob
pause_reason: manual_action
updated_at: "<ISO-8601 UTC now>"

Then stop. The harness will resume when the user runs flame-harness-resume.

Step 2 — Collect Ad Unit IDs

For each rewarded placement identified in the Strategy section, use AskUserQuestion to ask the user to create a rewarded ad unit in the AdMob console and paste back both the iOS and Android unit IDs. Example for a "revive" unit:

"In the AdMob console, under your app → Ad units → Add ad unit → Rewarded:

• Unit name: <app_slug>_rewarded_revive
• Copy the iOS unit ID (format: ca-app-pub-XXXX/IIII) and the Android unit ID (format: ca-app-pub-XXXX/AAAA).

Paste both here. Type 'defer' to pause."

Again apply the same pause_reason: manual_action pause if the user defers.

Step 3 — Write config.md admob block

Once all IDs are collected, write the admob: block in docs/harness/config.md (per protocol §1):

admob:
  enabled: true
  ios_app_id: "ca-app-pub-XXXX~YYYY"
  android_app_id: "ca-app-pub-XXXX~ZZZZ"
  ad_units:
    - key: rewarded_revive
      ios_id: "ca-app-pub-XXXX/IIII"
      android_id: "ca-app-pub-XXXX/AAAA"
      format: rewarded
    # add one entry per placement

---

Code Injection

After collecting IDs, inject the integration code into the Flutter project at <projects-dir>/<app_slug>/.

1. pubspec.yaml — Add Dependencies

dependencies:
  google_mobile_ads: ^5.1.0
  app_tracking_transparency: ^2.0.6

Run flutter pub get after editing.

2. iOS ATT Permission — Info.plist

Add to ios/Runner/Info.plist:

<key>NSUserTrackingUsageDescription</key>
<string>광고를 개인화하고 앱 개선을 위해 사용합니다.</string>

Add the iOS AdMob App ID:

<key>GADApplicationIdentifier</key>
<string>ca-app-pub-XXXX~YYYY</string>

Also add SKAdNetworkItems (Google's SKAdNetwork IDs from the official google_mobile_ads docs) to Info.plist — required for an ads build to pass App Store review (see docs/game-gotchas.md).

3. Android — AndroidManifest.xml + minSdk

Set minSdk = 23 in android/app/build.gradle.kts — google_mobile_ads requires API 23+ and a lower value crashes at startup (docs/game-gotchas.md). Then add to android/app/src/main/AndroidManifest.xml inside <application>:

<meta-data
    android:name="com.google.android.gms.ads.APPLICATION_ID"
    android:value="ca-app-pub-XXXX~ZZZZ"/>

4. ATT Request — lib/admob/att_helper.dart

Create lib/admob/att_helper.dart:

import 'dart:io';
import 'package:flutter/widgets.dart';
import 'package:app_tracking_transparency/app_tracking_transparency.dart';

/// Requests iOS App Tracking Transparency permission. No-op on Android.
///
/// CRITICAL — App Store Guideline 2.1: the ATT system dialog ONLY presents
/// while the app is active/foregrounded. On a fresh launch the app may not be
/// `resumed` yet, so requesting too early silently no-ops and the prompt never
/// appears — the exact cause of the "NSUserTrackingUsageDescription present but
/// the ATT alert never appears" 2.1 rejection on the latest iOS. So: wait until
/// resumed, add a small settle delay, and only request when notDetermined.
Future<void> requestATT() async {
  if (!Platform.isIOS) return;
  try {
    await _waitUntilResumed();
    final status = await AppTrackingTransparency.trackingAuthorizationStatus;
    if (status == TrackingStatus.notDetermined) {
      await Future<void>.delayed(const Duration(milliseconds: 400));
      await AppTrackingTransparency.requestTrackingAuthorization();
    }
  } catch (e) {
    debugPrint('ATT request failed: $e');
  }
}

/// Wait (up to ~4s) for the app to reach the foreground/active state, which is
/// required for the ATT prompt to actually present.
Future<void> _waitUntilResumed() async {
  for (var i = 0; i < 40; i++) {
    if (WidgetsBinding.instance.lifecycleState == AppLifecycleState.resumed) {
      return;
    }
    await Future<void>.delayed(const Duration(milliseconds: 100));
  }
}

Call requestATT() from a post-first-frame callback (WidgetsBinding.instance.addPostFrameCallback), and await it before loadConsentForm() and MobileAds.instance.initialize() so the ATT decision precedes any ad/tracking request (see §5). Never call it synchronously in main() before the first frame — that is what triggers the 2.1 rejection.

5. UMP Consent Flow — lib/admob/consent_helper.dart

Create lib/admob/consent_helper.dart:

import 'dart:async';
import 'package:flutter/foundation.dart';
import 'package:google_mobile_ads/google_mobile_ads.dart';

/// Loads and (if required) shows the UMP consent form.
/// Returns only after the consent callback fires — ads must NOT be
/// requested before this Future completes.
Future<void> loadConsentForm() async {
  final completer = Completer<void>();
  final params = ConsentRequestParameters();
  ConsentInformation.instance.requestConsentInfoUpdate(
    params,
    () async {
      if (await ConsentInformation.instance.isConsentFormAvailable()) {
        await ConsentForm.loadAndShowConsentFormIfRequired((_) {});
      }
      if (!completer.isCompleted) completer.complete();
    },
    (FormError error) {
      debugPrint('UMP consent error: ${error.message}');
      if (!completer.isCompleted) completer.complete(); // non-fatal, continue
    },
  );
  return completer.future;
}

Important: ads must NOT be requested before loadConsentForm() completes.

Use this startup order in main():

WidgetsFlutterBinding.ensureInitialized();
await requestATT();          // iOS only — no-op on Android
await loadConsentForm();     // waits for UMP consent decision
await MobileAds.instance.initialize();
// preload ads / runApp after this point

6. ID Switch — lib/admob/ad_ids.dart

Create lib/admob/ad_ids.dart. Use Google's official test IDs in debug builds to avoid policy violations; switch to real IDs in release:

import 'dart:io';

const bool _isDebug = bool.fromEnvironment('dart.vm.product') == false;

class AdIds {
  // ── Rewarded: revive ────────────────────────────────────────────────────
  static String get rewardedRevive {
    if (_isDebug) {
      return Platform.isIOS
          ? 'ca-app-pub-3940256099942544/1712485313'   // Google iOS test
          : 'ca-app-pub-3940256099942544/5224354917';  // Google Android test
    }
    return Platform.isIOS
        ? 'ca-app-pub-XXXX/IIII'   // from config.md admob.ad_units[rewarded_revive].ios_id
        : 'ca-app-pub-XXXX/AAAA';  // from config.md admob.ad_units[rewarded_revive].android_id
  }
  // Add one getter per ad unit.
}

Replace the placeholder strings with the IDs collected from the user.

7. Rewarded Helper — lib/admob/rewarded_ad_helper.dart

Create lib/admob/rewarded_ad_helper.dart:

import 'package:flutter/material.dart';
import 'package:google_mobile_ads/google_mobile_ads.dart';

/// Loads and shows a rewarded ad for a single placement.
/// Pass the ad unit ID from [AdIds] at construction time so the same
/// class can be reused for every placement (revive, bonus coins, etc.)
/// without subclassing.
///
/// Example:
///   final _reviveAd = RewardedAdHelper(AdIds.rewardedRevive);
///   final _bonusAd  = RewardedAdHelper(AdIds.rewardedBonus);
///
/// [onRewarded] is called when the user earns the reward.
/// [onDismissed] is called when the ad is dismissed (with or without reward).
class RewardedAdHelper {
  RewardedAdHelper(this.adUnitId);

  final String adUnitId;
  RewardedAd? _ad;

  Future<void> load() async {
    await RewardedAd.load(
      adUnitId: adUnitId,
      request: const AdRequest(),
      rewardedAdLoadCallback: RewardedAdLoadCallback(
        onAdLoaded: (ad) => _ad = ad,
        onAdFailedToLoad: (error) {
          debugPrint('RewardedAd failed to load: $error');
          _ad = null;
        },
      ),
    );
  }

  /// Returns true if an ad is ready.
  bool get isLoaded => _ad != null;

  /// Shows the ad. [onRewarded] fires when the user earns the reward.
  void show({
    required VoidCallback onRewarded,
    VoidCallback? onDismissed,
  }) {
    final ad = _ad;
    if (ad == null) {
      onDismissed?.call();
      return;
    }
    ad.fullScreenContentCallback = FullScreenContentCallback(
      onAdDismissedFullScreenContent: (ad) {
        ad.dispose();
        _ad = null;
        onDismissed?.call();
      },
      onAdFailedToShowFullScreenContent: (ad, error) {
        ad.dispose();
        _ad = null;
        onDismissed?.call();
      },
    );
    ad.show(onUserEarnedReward: (_, __) => onRewarded());
  }

  void dispose() {
    _ad?.dispose();
    _ad = null;
  }
}

8. Game Integration

In the game-over or revive overlay (identified in the Strategy section), call:

if (_rewardedAdHelper.isLoaded) {
  _rewardedAdHelper.show(
    onRewarded: () {
      // Grant the reward: restore health, give extra life, double coins, etc.
    },
    onDismissed: () {
      // User skipped ad — proceed to normal game-over flow.
    },
  );
}

Pre-load the ad when the game session starts so it is ready when needed. Instantiate one RewardedAdHelper per placement, passing the matching AdIds getter:

_reviveAdHelper = RewardedAdHelper(AdIds.rewardedRevive);
await _reviveAdHelper.load();
// Add one line per placement (e.g. RewardedAdHelper(AdIds.rewardedBonus))

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Output — Write State and Logs

After completing code injection and confirming flutter analyze returns 0 issues:

Write config.md

Ensure docs/harness/config.md admob: block is complete and accurate (see Step 3 above under Manual Unit Creation). Per protocol §1, the enabled field must be true when ads are injected.

Write state.md

Write docs/harness/state.md atomically (per protocol §7 admob → build transition and §7 rule 2 — set status: running in the same write):

status: running
current_phase: admob
next_role: build
updated_at: "<ISO-8601 UTC now>"

Leave current_round, created_at, resume_attempts, and pause_reason unchanged.

Append to pipeline-log.md

Append one row to docs/harness/pipeline-log.md (per protocol §6):

| <ISO-8601 UTC now> | complete | admob | rewarded ad injected; ATT+UMP wired; next: build |

---

Error Handling

• If flutter analyze fails after code injection, fix all issues before writing state.md.
• If the user cannot provide AdMob IDs (console access issue, approval pending), pause with pause_reason: manual_action and explain what is needed for resume.
• If app_tracking_transparency or google_mobile_ads pub.dev packages are unavailable, check the current package name with flutter pub search google_mobile_ads and update the version accordingly.