From 0be87ca89b80eddafab7b7f89394fcbd9e5bb4d8 Mon Sep 17 00:00:00 2001
From: Guy Sartorelli <guy.sartorelli@silverstripe.com>
Date: Wed, 6 Dec 2023 11:04:49 +1300
Subject: [PATCH] ENH Add permission methods based on owner

---
 src/Models/Link.php | 51 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/src/Models/Link.php b/src/Models/Link.php
index 78e9cb55..63df7e1e 100644
--- a/src/Models/Link.php
+++ b/src/Models/Link.php
@@ -270,6 +270,57 @@ public function getURL(): string
         return '';
     }
 
+    public function canView($member = null)
+    {
+        return $this->canPerformAction(__FUNCTION__, $member);
+    }
+
+    public function canEdit($member = null)
+    {
+        return $this->canPerformAction(__FUNCTION__, $member);
+    }
+
+    public function canDelete($member = null)
+    {
+        return $this->canPerformAction(__FUNCTION__, $member);
+    }
+
+    public function canCreate($member = null, $context = [])
+    {
+        return $this->canPerformAction(__FUNCTION__, $member);
+    }
+
+    public function can($perm, $member = null, $context = [])
+    {
+        $check = ucfirst(strtolower($perm));
+        return match ($check) {
+            'View', 'Create', 'Edit', 'Delete' => $this->{"can$check"}($member, $context),
+            default => parent::can($perm, $member, $context)
+        };
+    }
+
+    private function canPerformAction(string $canMethod, $member, $context = [])
+    {
+        // Allow extensions to override permission checks
+        $results = $this->extendedCan($canMethod, $member, $context);
+        if (isset($results)) {
+            return $results;
+        }
+
+        // If we have an owner, rely on it to tell us what we can and can't do
+        $owner = $this->Owner();
+        if ($owner && $owner->exists()) {
+            // Can delete or create links if you can edit its owner.
+            if ($canMethod === 'canCreate' || $canMethod === 'canDelete') {
+                $canMethod = 'canEdit';
+            }
+            return $owner->$canMethod($member, $context);
+        }
+
+        // Default to DataObject's permission checks
+        return parent::$canMethod($member, $context);
+    }
+
     /**
      * Get all link types except the generic one
      *