Fix upgrade price calculation for EAP customers selecting monthly billing

stripePriceId() checked EAP status before billing interval, so EAP
customers always got the yearly EAP price regardless of monthly/yearly
selection. Move the monthly interval check first since no monthly EAP
prices exist.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: simonhamp

app/Enums/Subscription.php

@@ -83,6 +83,12 @@ public function name(): string
 
     public function stripePriceId(bool $forceEap = false, bool $discounted = false, string $interval = 'year'): string
     {
+        // Monthly billing uses the regular monthly price (no EAP/discounted monthly prices exist)
+        if ($interval === 'month') {
+            return config("subscriptions.plans.{$this->value}.stripe_price_id_monthly")
+                ?? config("subscriptions.plans.{$this->value}.stripe_price_id");
+        }
+
         // EAP ends June 1st at midnight UTC
         if (now()->isBefore('2025-06-01 00:00:00') || $forceEap) {
             return config("subscriptions.plans.{$this->value}.stripe_price_id_eap");
@@ -92,10 +98,6 @@ public function stripePriceId(bool $forceEap = false, bool $discounted = false,
             return config("subscriptions.plans.{$this->value}.stripe_price_id_discounted");
         }
 
-        if ($interval === 'month') {
-            return config("subscriptions.plans.{$this->value}.stripe_price_id_monthly");
-        }
-
         return config("subscriptions.plans.{$this->value}.stripe_price_id");
     }
 

tests/Unit/SubscriptionStripePriceIdTest.php

@@ -0,0 +1,70 @@
+<?php
+
+namespace Tests\Unit;
+
+use App\Enums\Subscription;
+use Illuminate\Support\Facades\Config;
+use PHPUnit\Framework\Attributes\Test;
+use Tests\TestCase;
+
+class SubscriptionStripePriceIdTest extends TestCase
+{
+    private const YEARLY_PRICE = 'price_max_yearly';
+
+    private const MONTHLY_PRICE = 'price_max_monthly';
+
+    private const EAP_PRICE = 'price_max_eap';
+
+    private const DISCOUNTED_PRICE = 'price_max_discounted';
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        Config::set('subscriptions.plans.max.stripe_price_id', self::YEARLY_PRICE);
+        Config::set('subscriptions.plans.max.stripe_price_id_monthly', self::MONTHLY_PRICE);
+        Config::set('subscriptions.plans.max.stripe_price_id_eap', self::EAP_PRICE);
+        Config::set('subscriptions.plans.max.stripe_price_id_discounted', self::DISCOUNTED_PRICE);
+    }
+
+    #[Test]
+    public function yearly_returns_default_price(): void
+    {
+        $this->assertEquals(self::YEARLY_PRICE, Subscription::Max->stripePriceId());
+    }
+
+    #[Test]
+    public function monthly_returns_monthly_price(): void
+    {
+        $this->assertEquals(self::MONTHLY_PRICE, Subscription::Max->stripePriceId(interval: 'month'));
+    }
+
+    #[Test]
+    public function eap_yearly_returns_eap_price(): void
+    {
+        $this->assertEquals(self::EAP_PRICE, Subscription::Max->stripePriceId(forceEap: true));
+    }
+
+    #[Test]
+    public function eap_monthly_returns_monthly_price_not_eap(): void
+    {
+        $this->assertEquals(
+            self::MONTHLY_PRICE,
+            Subscription::Max->stripePriceId(forceEap: true, interval: 'month')
+        );
+    }
+
+    #[Test]
+    public function discounted_returns_discounted_price(): void
+    {
+        $this->assertEquals(self::DISCOUNTED_PRICE, Subscription::Max->stripePriceId(discounted: true));
+    }
+
+    #[Test]
+    public function monthly_falls_back_to_default_when_no_monthly_price(): void
+    {
+        Config::set('subscriptions.plans.max.stripe_price_id_monthly', null);
+
+        $this->assertEquals(self::YEARLY_PRICE, Subscription::Max->stripePriceId(interval: 'month'));
+    }
+}