Add subscription pricing and Base drawing limit

Services/EntitlementService.cs

@@ -1,10 +1,14 @@
 namespace LMEMappeCatastaliApp.Services;
 
-public sealed class EntitlementService(ManualLicenseService manualLicenses, IPlayBillingService playBilling)
+public sealed class EntitlementService(
+    ManualLicenseService manualLicenses,
+    IPlayBillingService playBilling,
+    PlayPurchaseVerificationService purchaseVerification)
 {
     public const string ProductId = "lme_pro";
     public const string MonthlyBasePlanId = "monthly";
     public const string YearlyBasePlanId = "yearly";
+    public const int BaseDrawingObjectLimit = 15;
 
     private const string GoogleProActivePreference = "entitlement_google_pro_active";
     private const string GoogleExpiresAtPreference = "entitlement_google_pro_expires_at";
@@ -53,6 +57,10 @@ public sealed class EntitlementService(ManualLicenseService manualLicenses, IPla
     public bool RequiresPro(string feature) => ProFeatures.Contains(feature);
     public bool CanUse(string feature) => !RequiresPro(feature) || HasProAccess;
 
+    public Task<IReadOnlyList<PlaySubscriptionPlan>> GetSubscriptionPlansAsync(
+        CancellationToken cancellationToken = default) =>
+        playBilling.GetSubscriptionPlansAsync(cancellationToken);
+
     public async Task LoadAsync()
     {
         IsGoogleProActive = Preferences.Default.Get(GoogleProActivePreference, false);
@@ -85,32 +93,60 @@ public sealed class EntitlementService(ManualLicenseService manualLicenses, IPla
     public async Task<PlayBillingResult> RestorePurchasesAsync()
     {
         var result = await playBilling.RestoreAsync();
-        ApplyPlayBillingResult(result);
-        return result;
+        return await ApplyPlayBillingResultAsync(result);
     }
 
     public async Task<PlayBillingResult> PurchaseGoogleProAsync(string basePlanId)
     {
         var result = await playBilling.PurchaseAsync(basePlanId);
-        ApplyPlayBillingResult(result);
-        return result;
+        return await ApplyPlayBillingResultAsync(result);
     }
 
-    private void ApplyPlayBillingResult(PlayBillingResult result)
+    private async Task<PlayBillingResult> ApplyPlayBillingResultAsync(PlayBillingResult result)
     {
         if (!result.Completed)
         {
-            return;
+            return result;
         }
 
         if (result.HasActiveSubscription)
         {
+            if (!string.IsNullOrWhiteSpace(result.PurchaseToken))
+            {
+                var verification = await purchaseVerification.VerifyAsync(result.PurchaseToken);
+                if (verification.Verified)
+                {
+                    if (verification.Active)
+                    {
+                        ApplyVerifiedGooglePro(verification.ExpiresAt);
+                        return result with
+                        {
+                            Message = string.IsNullOrWhiteSpace(verification.Message)
+                                ? result.Message
+                                : verification.Message
+                        };
+                    }
+
+                    ApplyGoogleBase();
+                    return PlayBillingResult.Base(string.IsNullOrWhiteSpace(verification.Message)
+                        ? "L'abbonamento Google Play non risulta attivo."
+                        : verification.Message);
+                }
+
+                if (purchaseVerification.IsRequired)
+                {
+                    return PlayBillingResult.Failed(verification.Message);
+                }
+            }
+
             ApplyVerifiedGooglePro(null);
         }
         else
         {
             ApplyGoogleBase();
         }
+
+        return result;
     }
 
     private void SaveGoogleState()