Support fixed day of month

CRM/Core/Payment/GoCardless.php

@@ -299,6 +299,12 @@ public function doPayment(&$params, $component = 'contribute') {
       ];
     }
 
+    // Added via javascript so "removed" by quickform after submission
+    $dayOfMonth = CRM_Utils_Request::retrieveValue('day_of_month', 'Integer', NULL, FALSE, 'POST');
+    if ($dayOfMonth) {
+      $params['day_of_month'] = $dayOfMonth;
+    }
+
     $url = $this->createRedirectFlow($params, $component);
     CRM_Utils_System::redirect($url);
   }
@@ -338,7 +344,7 @@ public function createRedirectFlow(&$params, $component) {
         'payment_processor_id' => $this->_paymentProcessor['id'],
         "description"          => $params['description'],
       ];
-      foreach (['contributionID', 'contributionRecurID', 'contactID', 'membershipID'] as $_) {
+      foreach (['contributionID', 'contributionRecurID', 'contactID', 'membershipID', 'day_of_month'] as $_) {
         if (!empty($params[$_])) {
           $sesh_store[$redirect_flow->id][$_] = $params[$_];
         }

CRM/GoCardlessUtils.php

@@ -222,6 +222,9 @@ public static function completeRedirectFlowWithGoCardless($deets) {
       'links'         => ['mandate' => $redirect_flow->links->mandate],
       'metadata'      => ['civicrm' => $metadata],
     ];
+    if ($deets['day_of_month']) {
+      $params['day_of_month'] = $deets['day_of_month'];
+    }
 
     if (isset($installments)) {
       $params['count'] = $installments;
@@ -483,9 +486,77 @@ public static function handleContributeFormHacks() {
         ->addWhere('is_test', 'IS NOT NULL')
         ->execute()
         ->column('id');
+
       $js = file_get_contents(E::path('js/gcform.js'));
-      $js = str_replace('var goCardlessProcessorIDs = [];', 'var goCardlessProcessorIDs = ' . json_encode($paymentProcessorsIDs) . ';', $js);
+      $js = str_replace([
+          'var goCardlessProcessorIDs = [];',
+          'var dayOfMonthOptions = {};'
+        ],
+        [
+          'var goCardlessProcessorIDs = ' . json_encode($paymentProcessorsIDs) . ';',
+          'var dayOfMonthOptions = ' . json_encode(self::getDayOfMonthOptions()) . ';'
+        ],
+        $js
+      );
       CRM_Core_Region::instance('page-body')->add(['markup' => "<script>$js</script>"]);
     }
   }
+
+  /**
+   * Get the formatted options for daysOfMonth eg. [1 => '1st']
+   * This is used for frontend presentation and backend settings
+   *
+   * @param bool $all
+   *
+   * @return array
+   */
+  public static function getDayOfMonthOptions($all = FALSE) {
+    if ($all) {
+      $options = [0];
+      for ($i = 1; $i <= 28; $i++) {
+        // Add days 1 to 28 (29-31 are excluded because don't exist for some months)
+        $options[] = $i;
+      }
+      $options[] = -1;
+    }
+    else {
+      $options = static::getSettings()['daysOfMonth'];
+    }
+
+    foreach ($options as $option) {
+      switch ($option) {
+        case 0:
+          $dayOfMonthOptions[$option] = 'auto';
+          break;
+
+        case -1:
+          $dayOfMonthOptions[$option] = 'last';
+          break;
+
+        default:
+          $dayOfMonthOptions[$option] = self::formatPreferredCollectionDay($option);
+      }
+    }
+    return $dayOfMonthOptions;
+  }
+
+  /**
+   * Format collection day like 1st, 2nd, 3rd, 4th etc.
+   *
+   * @param $collectionDay
+   *
+   * @return string
+   */
+  public static function formatPreferredCollectionDay($collectionDay) {
+    $ends = ['th', 'st', 'nd', 'rd', 'th', 'th', 'th', 'th', 'th', 'th'];
+    if ((($collectionDay%100) >= 11) && (($collectionDay%100) <= 13)) {
+      $abbreviation = $collectionDay . 'th';
+    }
+    else {
+      $abbreviation = $collectionDay . $ends[$collectionDay % 10];
+    }
+
+    return $abbreviation;
+  }
+
 }

ang/gocardless/GoCardlessSettings.html

@@ -40,6 +40,24 @@ <h1 crm-page-title>{{ts('GoCardless settings')}}</h1>
         </div>
       </div>
 
+      <div class="crm-section">
+        <div crm-ui-field="{name: 'myForm.daysOfMonth', title: ts('Allowed days of month')}">
+          <select
+            crm-ui-id="myForm.daysOfMonth"
+            ng-model="gcSettings.daysOfMonth"
+            name="daysOfMonth"
+            class="crm-form-select"
+            multiple
+            size="15"
+          >
+            <option ng-repeat="item in gcDaysOfMonth" value="{{item.key}}">{{item.value}}</option>
+          </select>
+          <p>The allowed days of the month. Set to "auto" for the next available date or "last" for the last day of the month.
+            <br/><em>This only works if "Force Recurring" is enabled and "Monthly" or "Yearly" is selected.</em>
+          </p>
+        </div>
+      </div>
+
     </div>
 
     <div>

ang/gocardless/GoCardlessSettings.js

@@ -52,7 +52,8 @@
     // Annoyingly this is duplicated from CRM_GoCardlessUtils::getSettings()
     const defaults = {
       forceRecurring: false,
-      sendReceiptsForCustomPayments: 'never'
+      sendReceiptsForCustomPayments: 'never',
+      daysOfMonth: ["0"]
     };
     Object.keys(defaults).forEach(k => {
       if (!(k in gcSettings)) {
@@ -61,6 +62,12 @@
     });
     $scope.gcSettings = gcSettings;
 
+    const m={1:'1st', 2:'2nd', 3:'3rd', 21:'21st', 22:'22nd', 23:'23rd'};
+    const daysOfMonthOpts = [{key: '0', value: 'any day (earliest possible)'}];
+    for (var i=1;i<29;i++) daysOfMonthOpts.push({key: i.toString(), value: m[i] || (i + 'th')});
+    daysOfMonthOpts.push({key: '-1', value: 'last day of month'});
+    $scope.gcDaysOfMonth = daysOfMonthOpts;
+
     // Make pay processors accessible
     var ppTable = [];
     var ppNames = {};

docs/reference/settings.md

@@ -1,6 +1,6 @@
 # Settings Page
 
-![Screnshot of settings page](../gc-settings.jpg)
+![Screnshot of settings page](../gc-settings.png)
 
 ## Force Recurring
 
@@ -60,3 +60,16 @@ in some custom code, you might not have set this `is_email_receipt` value.
   and will pass 0 or 1 into the payment APIs.
 
 - `defer` will pass in the value from the recurring contribution record.
+
+## Allowed days of the month
+
+The allowed days of the month.
+Set to "auto" for the next available date or "last" for the last day of the month.
+You can specify multiple options and it will give the user a choice when setting up the payment.
+
+This only works if "Force Recurring" is enabled and "Monthly" or "Yearly" is selected.
+
+#### Developers notes
+* The GoCardless API also supports specifying "month" for "Yearly subscriptions" but that is not currently implemented.
+* The "Force recurring" setting is required because we are sharing the `gcform.js` code and it was simpler to implement that way.
+

info.xml

@@ -22,6 +22,9 @@
   <compatibility>
     <ver>5.35</ver>
   </compatibility>
+  <classloader>
+    <psr4 prefix="Civi\" path="Civi"/>
+  </classloader>
   <civix>
     <namespace>CRM/GoCardless</namespace>
   </civix>