rules_version = '2';
service cloud.firestore {
  match /databases/{database}/documents {

    function isSignedIn() {
      return request.auth != null;
    }

    function isAdmin() {
      return isSignedIn() && request.auth.token.admin == true;
    }

    function isAdminEmail() {
      return isSignedIn()
        && request.auth.token.email_verified == true
        && exists(/databases/$(database)/documents/admin_users/$(authEmail()));
    }

    function isConfiguredAdmin() {
      return isAdmin() || isAdminEmail();
    }

    function isOwner(uid) {
      return isSignedIn() && request.auth.uid == uid;
    }

    function hasAuthEmail() {
      return isSignedIn() && request.auth.token.get('email', '') is string
          && request.auth.token.get('email', '') != '';
    }

    function authEmail() {
      return request.auth.token.email;
    }

    function isEmailOwner(email) {
      return hasAuthEmail() && request.auth.token.email_verified == true
          && email is string && email == authEmail();
    }

    // favouriteWallToDoc stores string ids for every provider, including Pexels numeric ids.
    // Optional media/metadata fields vary by provider and by shipped client version.
    function validFavourite(docId) {
      let data = request.resource.data;
      return data.id is string && data.id == docId
          && data.provider is string
          && data.provider.lower() in ['prism', 'wall_of_the_day', 'walloftheday', 'wallhaven', 'pexels'];
    }

    // A follow that is already in place (arrayUnion of a present email) is a no-op write; allow it so a
    // batch of follows does not fail on one creator the user already follows.
    function canToggleFollowersOnly() {
      let affected = request.resource.data.diff(resource.data).affectedKeys();
      return hasAuthEmail() && request.auth.token.email_verified == true
          && affected.hasOnly(['followers'])
          && (affected.size() == 0
              || (resource.data.followers is list
                  && request.resource.data.followers is list
                  && request.resource.data.followers.removeAll([authEmail()])
                      == resource.data.followers.removeAll([authEmail()])
                  && ((!resource.data.followers.hasAny([authEmail()])
                        && request.resource.data.followers.size() == resource.data.followers.size() + 1)
                      || !request.resource.data.followers.hasAny([authEmail()]))));
    }

    // New profiles start empty: coins, premium and coinState are server-owned.
    function canCreateUserDoc(userId) {
      return isOwner(userId)
          && request.resource.data.id is string
          && request.resource.data.id == userId
          && (!('email' in request.resource.data)
              || (hasAuthEmail() && request.resource.data.email == authEmail())
              || (!hasAuthEmail() && request.resource.data.email == ''))
          // A candidate is not an identity. Only the server reservation transaction publishes the username.
          && request.resource.data.get('username', '') == ''
          && !('usernameLower' in request.resource.data)
          && ownerAppOpenValuesOk(request.resource.data)
          && request.resource.data.get('coins', 0) == 0
          && request.resource.data.get('premium', false) == false
          && request.resource.data.get('subscriptionTier', 'free') == 'free'
          && request.resource.data.get('followers', []).size() == 0
          && request.resource.data.get('badges', []).size() == 0
          && !('coinState' in request.resource.data)
          && !request.resource.data.keys().hasAny(['xp', 'xpWeek', 'cosmetics', 'quests', 'inventory', 'drops']);
    }

    // Owners may only touch the client-side coinState keys; award flags stay server-owned.
    function ownerCoinStateOk() {
      return !request.resource.data.diff(resource.data).affectedKeys().hasAny(['coinState'])
          || request.resource.data.coinState.diff(resource.data.get('coinState', {})).affectedKeys().hasOnly([
            'premiumPreviewUnlocks', 'streakReminderEnabled', 'streakTimezoneOffsetMinutes', 'streakReminderNextAtUtc'
          ]);
    }

    // lastAppOpenAt is a server timestamp, so it matches request.time. A raw write can be at most
    // 5 minutes old, or 1 minute ahead, and the offset stays on the 15 minute grid.
    function ownerAppOpenTimestampOk(data) {
      return data.lastAppOpenAt is timestamp
          && data.lastAppOpenAt <= request.time + duration.value(1, 'm')
          && data.lastAppOpenAt >= request.time - duration.value(5, 'm');
    }

    function ownerAppOpenOffsetOk(data) {
      let offset = data.appOpenTimezoneOffsetMinutes;
      return offset is int && offset >= -720 && offset <= 840 && offset % 15 == 0;
    }

    function ownerAppOpenValuesOk(data) {
      let openAtOk = !('lastAppOpenAt' in data)
          || ownerAppOpenTimestampOk(data);
      let offsetOk = !('appOpenTimezoneOffsetMinutes' in data)
          || ownerAppOpenOffsetOk(data);
      return openAtOk && offsetOk;
    }

    function ownerAppOpenOk() {
      let changed = request.resource.data.diff(resource.data).affectedKeys();
      let timestampOk = !changed.hasAny(['lastAppOpenAt'])
          || ownerAppOpenTimestampOk(request.resource.data);
      let offsetOk = !changed.hasAny(['appOpenTimezoneOffsetMinutes'])
          || ownerAppOpenOffsetOk(request.resource.data);
      return timestampOk && offsetOk;
    }

    function wallServerKeysAbsent() {
      return !request.resource.data.keys().hasAny(['dropReserved', 'dropWeek', 'boostedUntil', 'depth', 'originalProtected', 'originalObjectId', 'moderation', 'visionLabels', 'searchTerms']);
    }

    function wallServerKeysUntouched() {
      return !request.resource.data.diff(resource.data).affectedKeys().hasAny(['dropReserved', 'dropWeek', 'boostedUntil', 'depth', 'originalProtected', 'originalObjectId', 'moderation', 'visionLabels', 'searchTerms']);
    }

    // Wall of the Day — public read, admin-only write (set via Cloud Function)
    match /wall_of_the_day/{docId} {
      allow read: if true;
      allow write: if isConfiguredAdmin();
    }

    // Past Picks — public read, admin-only write (archived by Cloud Function)
    match /past_picks/{docId} {
      allow read: if true;
      allow write: if isConfiguredAdmin();
    }

    // Legacy/ops config
    match /appConfig/{docId} {
      allow read: if true;
      allow write: if isConfiguredAdmin();
    }

    // Public app metadata (icons, etc.)
    match /apps/{docId} {
      allow read: if true;
      allow write: if isConfiguredAdmin();
    }

    // Public feeds; unreviewed docs are owner/admin only.
    match /walls/{docId} {
      // Reviewed walls stay readable while 3.7.0 clients are installed: they read unconverted walls and the original URL.
      // Tighten this to review == true && originalProtected == true && wallpaper_url == '' (and the four provenance
      // fields == '') once 3.7.0 share is low. 3.8.0 clients already filter to protected walls on their side.
      allow read: if resource.data.review == true || isEmailOwner(resource.data.email) || isConfiguredAdmin();
      // Admins re-create a rejected wall when they undo the rejection.
      allow create: if isConfiguredAdmin()
          || (isSignedIn()
              && isEmailOwner(request.resource.data.email)
              && request.resource.data.review != true
              && wallServerKeysAbsent());
      // delete: request.resource is null — do not use request.resource.data here.
      allow update: if isConfiguredAdmin()
          || (isEmailOwner(resource.data.email)
              && wallServerKeysUntouched()
              && request.resource.data.email == resource.data.email
              && resource.data.review != true
              && request.resource.data.review != true);
      allow delete: if isConfiguredAdmin()
          || (isEmailOwner(resource.data.email) && resource.data.review != true);
    }

    match /setups/{docId} {
      allow read: if resource.data.review == true || isEmailOwner(resource.data.email) || isConfiguredAdmin();
      allow create: if isSignedIn()
          && isEmailOwner(request.resource.data.email)
          && request.resource.data.review != true;
      allow update: if isConfiguredAdmin()
          || (isEmailOwner(resource.data.email)
              && request.resource.data.email == resource.data.email
              && resource.data.review != true
              && request.resource.data.review != true);
      allow delete: if isConfiguredAdmin()
          || (isEmailOwner(resource.data.email) && resource.data.review != true);
    }

    // Drafts are private to their owner.
    match /draftSetups/{docId} {
      allow read: if isConfiguredAdmin() || isEmailOwner(resource.data.email);
      allow create: if isConfiguredAdmin() || isEmailOwner(request.resource.data.email);
      allow update: if isConfiguredAdmin()
          || (isEmailOwner(resource.data.email) && request.resource.data.email == resource.data.email);
      allow delete: if isConfiguredAdmin() || isEmailOwner(resource.data.email);
    }

    // Rejection archives are private to owner/admin.
    // The owner may delete a rejected item from their own list.
    match /rejectedWalls/{docId} {
      allow read: if isConfiguredAdmin() || isEmailOwner(resource.data.email);
      allow write: if isConfiguredAdmin();
      allow delete: if isEmailOwner(resource.data.email);
    }

    match /rejectedSetups/{docId} {
      allow read: if isConfiguredAdmin() || isEmailOwner(resource.data.email);
      allow write: if isConfiguredAdmin();
      allow delete: if isEmailOwner(resource.data.email);
    }

    // Legacy public content bucket.
    match /setupsv3/{docId} {
      allow read: if true;
      allow write: if isConfiguredAdmin();
    }

    // Curated collections shown in feeds.
    match /collections/{docId} {
      allow read: if true;
      allow write: if isConfiguredAdmin();
    }

    // User profiles + private user state.
    // Signed-in users can read social profiles. ponytail: field-level private
    // coins/email needs a profiles collection plus a migration.
    match /usersv2/{userId} {
      allow read: if isSignedIn();
      allow create: if canCreateUserDoc(userId) || isConfiguredAdmin();
      allow update: if (isOwner(userId) && request.resource.data.diff(resource.data).affectedKeys().hasOnly([
            'name', 'profilePhoto', 'coverPhoto', 'bio', 'links', 'lastLoginAt', 'loggedIn',
            'following', 'interestCategories', 'onboardingV2', 'uploadsWeekStart',
            'uploadsThisWeek', 'id', 'createdAt', 'updatedAt', 'coinState',
            'lastAppOpenAt', 'appOpenTimezoneOffsetMinutes'
          ]) && ownerCoinStateOk() && ownerAppOpenOk())
          || canToggleFollowersOnly()
          || isConfiguredAdmin();
      allow delete: if isConfiguredAdmin();

      // Coin economy state (quests, inventory, unlocked drops, passes): owner read, server write.
      match /private/economy {
        allow read: if isOwner(userId) || isConfiguredAdmin();
        allow write: if false;
      }

      match /private/session {
        allow read, write: if isOwner(userId) || isConfiguredAdmin();
      }

      // Block list: owner can read; writes only via Cloud Functions (Admin SDK).
      match /blockedUsers/{blockedId} {
        allow read: if isOwner(userId);
        allow create, update, delete: if false;
      }

      // Per-user favourites subcollections.
      match /images/{docId} {
        allow read, delete: if isOwner(userId) || isConfiguredAdmin();
        allow create, update: if (isOwner(userId) && validFavourite(docId)) || isConfiguredAdmin();
      }

      match /setups/{docId} {
        allow read, create, update, delete: if isOwner(userId) || isConfiguredAdmin();
      }
    }

    // Legacy users collection.
    match /users/{userId} {
      allow read, write: if isConfiguredAdmin() || isOwner(userId);
    }

    // Notifications are readable by signed-in users; only admins/functions write.
    match /notifications/{docId} {
      allow read: if isSignedIn()
          && (hasAuthEmail() && resource.data.modifier == authEmail()
              || resource.data.modifier in ['all', 'premium', 'free']
              || resource.data.modifier == request.auth.uid
              || resource.data.modifier.matches('^[0-9]+([.][0-9]+)*$'));
      allow write: if isConfiguredAdmin();
    }

    // Admin-triggered notification queue.
    match /notificationRequests/{docId} {
      allow read, write: if isConfiguredAdmin();
    }

    // Referral/redeem codes. Admin-only: the Enter Code feature was removed client-side,
    // and any signed-in user could otherwise read every code in the collection.
    match /codes/{docId} {
      allow read, write: if isConfiguredAdmin();
    }

    // AI generation history is private per user.
    match /aiGenerations/{docId} {
      allow read: if isConfiguredAdmin() || (isSignedIn() && resource.data.userId == request.auth.uid);
      allow create: if isConfiguredAdmin() || (isSignedIn() && request.resource.data.userId == request.auth.uid);
      allow update: if isConfiguredAdmin() || (isSignedIn()
          && resource.data.userId == request.auth.uid
          && request.resource.data.userId == request.auth.uid);
      allow delete: if isConfiguredAdmin() || (isSignedIn() && resource.data.userId == request.auth.uid);
    }

    // Coin transaction ledger is private per user.
    match /coinTransactions/{docId} {
      allow read: if isConfiguredAdmin() || (isSignedIn() && resource.data.userId == request.auth.uid);
      allow write: if false;
    }

    // Legacy token storage (if used, doc id should be UID).
    match /tokens/{userId} {
      allow read, write: if isConfiguredAdmin() || isOwner(userId);
    }

    // UGC reports (created via submitContentReport callable). Admin read/update for moderation UI.
    match /contentReports/{docId} {
      allow read: if isConfiguredAdmin();
      allow create, delete: if false;
      allow update: if isConfiguredAdmin();
    }

    // Rate-limit state for content reports (Cloud Functions only).
    match /contentReportRateByTarget/{docId} {
      allow read, write: if false;
    }

    match /contentReportRateDaily/{docId} {
      allow read, write: if false;
    }

    // User block rate limits (Cloud Functions only).
    match /userBlockRateDaily/{docId} {
      allow read, write: if false;
    }

    match /userBlockRateByTarget/{docId} {
      allow read, write: if false;
    }

    // Public view counters (writes via Cloud Functions Admin SDK only).
    match /wallpaper_stats/{docId} {
      allow read: if true;
      allow write: if false;
    }

    match /setup_stats/{docId} {
      allow read: if true;
      allow write: if false;
    }

    // Trending and popular wallpaper ids, written by the computeTrending function.
    match /trending/{docId} {
      allow read: if true;
      allow write: if false;
    }

    match /popular/{docId} {
      allow read: if true;
      allow write: if false;
    }

    // Username registry (claimUsername callable). Signed-in users can read it.
    match /usernames/{name} {
      allow read: if isSignedIn();
      allow write: if false;
    }

    // Daily push counts. Cloud Functions write them. Admins read the day rows.
    match /metrics/{docId} {
      allow read: if isConfiguredAdmin();
      allow write: if false;

      match /days/{dayId} {
        allow read: if isConfiguredAdmin();
        allow write: if false;
      }

      match /signals/{signalId} {
        allow read, write: if false;
      }
    }

    // Coin economy v2. Config, drops, boosts, draws and leaderboards are read-only to signed-in users.
    // questEventRate and giftRateDaily have no match: default deny.
    match /economyConfig/{docId} {
      allow read: if true;
      allow write: if false;
    }

    match /drops/{weekKey} {
      allow read: if isSignedIn();
      allow write: if false;
    }

    match /boosts/{wallId} {
      allow read: if isSignedIn();
      allow write: if false;
    }

    match /draws/{weekKey} {
      allow read: if isSignedIn();
      allow write: if false;
    }

    match /drawTickets/{ticketId} {
      // The id is `{weekKey}_{uid}`, so the owner can read a ticket that does not exist yet.
      allow get: if isSignedIn() && ticketId == ticketId.split('_')[0] + '_' + request.auth.uid;
      allow list: if isSignedIn() && resource.data.uid == request.auth.uid;
      allow write: if false;
    }

    match /leaderboards/{weekKey} {
      allow read: if isSignedIn();
      allow write: if false;
    }

    // Deny everything else by default.
    match /{document=**} {
      allow read, write: if false;
    }
  }
}