From 26b9275f35c8b09c6a3c0023ccb46c469b3f9da9 Mon Sep 17 00:00:00 2001
From: Matthew Wire <mjw@mjwconsult.co.uk>
Date: Tue, 14 Sep 2021 16:47:26 +0100
Subject: [PATCH] Don't allow changing amount on UpdateSubscription form

---
 CRM/Contribute/Form/UpdateSubscription.php           | 10 +++++++++-
 templates/CRM/Contribute/Form/UpdateSubscription.tpl |  6 ++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/CRM/Contribute/Form/UpdateSubscription.php b/CRM/Contribute/Form/UpdateSubscription.php
index e38baacc44..a5772c74ce 100644
--- a/CRM/Contribute/Form/UpdateSubscription.php
+++ b/CRM/Contribute/Form/UpdateSubscription.php
@@ -151,10 +151,18 @@ class CRM_Contribute_Form_UpdateSubscription extends CRM_Contribute_Form_Contrib
     if (count($lineItems) > 1) {
       $amtAttr += ['readonly' => TRUE];
     }
-    $this->addMoney('amount', ts('Recurring Contribution Amount'), TRUE, $amtAttr,
+    $amountField = $this->addMoney('amount', ts('Recurring Contribution Amount'), TRUE, $amtAttr,
       TRUE, 'currency', $this->_subscriptionDetails->currency, TRUE
     );
 
+    // The amount on the recurring contribution should not be updated directly. If we update the amount using a template contribution the recurring contribution
+    //   will be updated automatically.
+    $paymentProcessorObj = Civi\Payment\System::singleton()->getById(CRM_Contribute_BAO_ContributionRecur::getPaymentProcessorID($this->contributionRecurID));
+    $templateContribution = CRM_Contribute_BAO_ContributionRecur::getTemplateContribution($this->contributionRecurID);
+    if (!empty($templateContribution['id']) && $paymentProcessorObj->supportsEditRecurringContribution()) {
+      $amountField->freeze();
+    }
+
     $this->add('text', 'installments', ts('Number of Installments'), ['size' => 20], FALSE);
 
     if ($this->_donorEmail) {
diff --git a/templates/CRM/Contribute/Form/UpdateSubscription.tpl b/templates/CRM/Contribute/Form/UpdateSubscription.tpl
index 06f77a01b2..c49249f3b0 100644
--- a/templates/CRM/Contribute/Form/UpdateSubscription.tpl
+++ b/templates/CRM/Contribute/Form/UpdateSubscription.tpl
@@ -19,6 +19,12 @@
     </div>
   {/if}
   <div class="crm-submit-buttons">{include file="CRM/common/formButtons.tpl" location="top"}</div>
+  {if $form.amount.frozen}
+  <div class="help">
+    {icon icon="fa-info-circle"}{/icon}
+    {ts}To change the amount you need to edit the template contribution. Click on "View Template" and then "Edit" from the list of recurring contributions{/ts}
+  </div>
+  {/if}
   <table class="form-layout">
     <tr>
       <td class="label">{$form.amount.label}</td>
-- 
2.25.1