From 052ed99fe79ee41b202560a9cc17855f02e5e529 Mon Sep 17 00:00:00 2001
From: Guy Sartorelli <guy.sartorelli@silverstripe.com>
Date: Tue, 13 Sep 2022 16:08:18 +1200
Subject: [PATCH] NEW Add an extension to dynamically generate edit URLs

---
 code/CMSEditLinkExtension.php                 | 149 ++++++++++++++++++
 code/ModelAdmin.php                           |   4 +-
 tests/php/CMSEditLinkExtensionTest.php        |  97 ++++++++++++
 tests/php/CMSEditLinkExtensionTest.yml        |  33 ++++
 .../BasicNestedObject.php                     |  26 +++
 .../BelongsToModelAdmin.php                   |  37 +++++
 .../CMSEditModelAdmin.php                     |  15 ++
 .../CMSEditLinkExtensionTest/NestedObject.php |  28 ++++
 .../PolymorphicNestedObject.php               |  26 +++
 tests/php/ModelAdminTest.php                  |   8 +-
 10 files changed, 417 insertions(+), 6 deletions(-)
 create mode 100644 code/CMSEditLinkExtension.php
 create mode 100644 tests/php/CMSEditLinkExtensionTest.php
 create mode 100644 tests/php/CMSEditLinkExtensionTest.yml
 create mode 100644 tests/php/CMSEditLinkExtensionTest/BasicNestedObject.php
 create mode 100644 tests/php/CMSEditLinkExtensionTest/BelongsToModelAdmin.php
 create mode 100644 tests/php/CMSEditLinkExtensionTest/CMSEditModelAdmin.php
 create mode 100644 tests/php/CMSEditLinkExtensionTest/NestedObject.php
 create mode 100644 tests/php/CMSEditLinkExtensionTest/PolymorphicNestedObject.php

diff --git a/code/CMSEditLinkExtension.php b/code/CMSEditLinkExtension.php
new file mode 100644
index 000000000..f952bee2a
--- /dev/null
+++ b/code/CMSEditLinkExtension.php
@@ -0,0 +1,149 @@
+<?php
+
+namespace SilverStripe\Admin;
+
+use LogicException;
+use SilverStripe\CMS\Controllers\CMSMain;
+use SilverStripe\Control\Controller;
+use SilverStripe\Control\Director;
+use SilverStripe\Core\Extension;
+use SilverStripe\Forms\FieldList;
+use SilverStripe\Forms\GridField\GridField;
+use SilverStripe\Forms\GridField\GridFieldDetailForm;
+use SilverStripe\ORM\DataObject;
+
+/**
+ * An extension that automatically generates a CMS edit link for DataObjects even if
+ * they are canonically edited in some nested {@link GridField}.
+ * Designed to be used in conjunction with the {@link CMSPreviewable} interface.
+ *
+ * For nested relations (e.g. a DataObject managed in a GridField of another DataObject)
+ * you can apply this extension to both the parent and the child object and the links
+ * will chain down the nested `GridField`s to the root cms edit owner.
+ *
+ * You must set a cms_edit_owner config variable which defines the cms edit
+ * owner for this class.
+ * e.g. set this to a {@link LeftAndMain} class:
+ * private static string cms_edit_owner = MyModelAdmin::class;
+ * or to a has_one relation:
+ * private static string cms_edit_owner = 'Parent';
+ *
+ * Note that the cms edit owner must implement a getCMSEditLinkForManagedDataObject() method.
+ *
+ * If the cms edit owner is a has_one relation, the class on the other end
+ * of the relation must have a CMSEditLink() method.
+ */
+class CMSEditLinkExtension extends Extension
+{
+    private static string $cms_edit_owner = '';
+
+    /**
+     * Get the admin or DataObject which owns this object for CMS editing purposes.
+     *
+     * @return LeftAndMain|DataObject|null
+     */
+    public function getCMSEditOwner()
+    {
+        $ownerType = $this->owner->config()->get('cms_edit_owner');
+        if (is_subclass_of($ownerType, LeftAndMain::class)) {
+            return $ownerType::singleton();
+        }
+        return $this->owner->getComponent($ownerType);
+    }
+
+    /**
+     * Get the link for editing an object from the CMS edit form of this object.
+     * @throws LogicException if a link cannot be established
+     * e.g. if the object is not in a has_many relation or not edited inside a GridField.
+     */
+    public function getCMSEditLinkForManagedDataObject(DataObject $obj, string $reciprocalRelation): string
+    {
+        $fields = $this->owner->getCMSFields();
+        $link = $this->getCMSEditLinkForRelation($this->owner->hasMany(false), $obj, $reciprocalRelation, $fields);
+        if (!$link) {
+            throw new LogicException('Could not produce an edit link for the passed object.');
+        }
+        return $link;
+    }
+
+    /**
+     * Get a link to edit this DataObject in the CMS.
+     */
+    public function CMSEditLink(): string
+    {
+        $owner = $this->owner->getCMSEditOwner();
+        if (!$owner || !$owner->exists()) {
+            return '';
+        }
+
+        if (!$owner->hasMethod('getCMSEditLinkForManagedDataObject')) {
+            throw new LogicException('The cms edit owner must implement getCMSEditLinkForManagedDataObject()');
+        }
+
+        if ($owner instanceof DataObject) {
+            $relativeLink = $owner->getCMSEditLinkForManagedDataObject($this->owner, $this->owner->config()->get('cms_edit_owner'));
+        } else {
+            $relativeLink = $owner->getCMSEditLinkForManagedDataObject($this->owner);
+        }
+        return Director::absoluteURL($relativeLink);
+    }
+
+    private function getCMSEditLinkForRelation(array $componentConfig, DataObject $obj, string $reciprocalRelation, FieldList $fields): string
+    {
+        $candidate = null;
+        foreach ($componentConfig as $relation => $class) {
+            // Check for dot notation being used to explicitly mark the reciprocal relation.
+            $remoteField = null;
+            if (strpos($class ?? '', '.') !== false) {
+                list($class, $remoteField) = explode('.', $class ?? '');
+            }
+
+            // We're only interested in relations to the $obj class.
+            if (!is_a($obj, $class)) {
+                continue;
+            }
+
+            if ($remoteField) {
+                if ($remoteField === $reciprocalRelation) {
+                    // We've found a direct reciprocal relation, so this is definitely correct.
+                    if ($this->relationIsEditable($relation, $fields)) {
+                        return $this->constructLink($relation, $obj->ID);
+                    }
+                    // If the relation isn't in a gridfield, we have no link for it.
+                    return '';
+                }
+                // We're not interested in unrelated relations.
+                continue;
+            }
+
+            // Check for relations that have gridfields we can build a link from.
+            if ($this->relationIsEditable($relation, $fields)) {
+                $candidate = $relation;
+            }
+        }
+
+        // Only do this if we didn't find a direct reciprocal relation.
+        return $candidate ? $this->constructLink($candidate, $obj->ID) : '';
+    }
+
+    private function relationIsEditable(string $relation, FieldList $fields): bool
+    {
+        $field = $fields->dataFieldByName($relation);
+        return $field
+            && $field instanceof GridField
+            && $field->getConfig()->getComponentByType(GridFieldDetailForm::class);
+    }
+
+    private function constructLink(string $relation, int $id): string
+    {
+        $ownerType = $this->owner->config()->get('cms_edit_owner');
+        $prefix = is_a($ownerType, CMSMain::class, true) ? 'field' : 'ItemEditForm/field';
+        return Controller::join_links(
+            $this->owner->CMSEditLink(),
+            $prefix,
+            $relation,
+            'item',
+            $id
+        );
+    }
+}
diff --git a/code/ModelAdmin.php b/code/ModelAdmin.php
index b510376a4..c0a33681c 100644
--- a/code/ModelAdmin.php
+++ b/code/ModelAdmin.php
@@ -227,7 +227,7 @@ public function getLinkForModelTab(string $modelTab): string
      *
      * @throws InvalidArgumentException if $obj is not managed by this ModelAdmin.
      */
-    public function getEditLinkForManagedDataObject(DataObject $obj): string
+    public function getCMSEditLinkForManagedDataObject(DataObject $obj): string
     {
         $modelTab = $this->getModelTabForModelClass($obj->ClassName);
         if ($modelTab === null) {
@@ -450,7 +450,7 @@ public function SearchForm()
      * }
      * </code>
      *
-     * Note: If you override this method you may also need to override getEditLinkForManagedDataObject()
+     * Note: If you override this method you may also need to override getCMSEditLinkForManagedDataObject()
      *
      * @return \SilverStripe\ORM\DataList
      */
diff --git a/tests/php/CMSEditLinkExtensionTest.php b/tests/php/CMSEditLinkExtensionTest.php
new file mode 100644
index 000000000..140c5857f
--- /dev/null
+++ b/tests/php/CMSEditLinkExtensionTest.php
@@ -0,0 +1,97 @@
+<?php
+
+namespace SilverStripe\Admin\Tests;
+
+use LogicException;
+use SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\BasicNestedObject;
+use SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\BelongsToModelAdmin;
+use SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\CMSEditModelAdmin;
+use SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\NestedObject;
+use SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\PolymorphicNestedObject;
+use SilverStripe\Dev\SapphireTest;
+
+class CMSEditLinkExtensionTest extends SapphireTest
+{
+    protected static $fixture_file = 'CMSEditLinkExtensionTest.yml';
+
+    protected $usesDatabase = true;
+
+    protected static $extra_dataobjects = [
+        BelongsToModelAdmin::class,
+        BasicNestedObject::class,
+        NestedObject::class,
+        PolymorphicNestedObject::class,
+    ];
+
+    protected static $extra_controllers = [
+        CMSEditModelAdmin::class,
+    ];
+
+    public function testGetCMSEditOwner()
+    {
+        $adminSingleton = CMSEditModelAdmin::singleton();
+        $root = $this->objFromFixture(BelongsToModelAdmin::class, 'root');
+        $basicNested = $this->objFromFixture(BasicNestedObject::class, 'one');
+        $nested = $this->objFromFixture(NestedObject::class, 'one');
+        $polymorphic = $this->objFromFixture(PolymorphicNestedObject::class, 'one');
+
+        $this->assertSame($adminSingleton, $root->getCMSEditOwner());
+        $this->assertSame($root->ID, $basicNested->getCMSEditOwner()->ID);
+        $this->assertSame($root->ID, $nested->getCMSEditOwner()->ID);
+        $this->assertSame($root->ID, $polymorphic->getCMSEditOwner()->ID);
+    }
+
+    public function testGetEditLinkForDataObject()
+    {
+        $root = $this->objFromFixture(BelongsToModelAdmin::class, 'root');
+        $basicNested = $this->objFromFixture(BasicNestedObject::class, 'one');
+        $nested = $this->objFromFixture(NestedObject::class, 'one');
+        $polymorphic = $this->objFromFixture(PolymorphicNestedObject::class, 'one');
+
+        $rootUrl = "http://localhost/admin/cms-edit-test/belongsHere/EditForm/field/belongsHere/item/$root->ID";
+        $this->assertSame(
+            "$rootUrl/ItemEditForm/field/BasicNested/item/$basicNested->ID",
+            $root->getCMSEditLinkForManagedDataObject($basicNested, 'Parent')
+        );
+        $this->assertSame(
+            "$rootUrl/ItemEditForm/field/Nested/item/$nested->ID",
+            $root->getCMSEditLinkForManagedDataObject($nested, 'Parent')
+        );
+        $this->assertSame(
+            "$rootUrl/ItemEditForm/field/PolyMorphic/item/$polymorphic->ID",
+            $root->getCMSEditLinkForManagedDataObject($polymorphic, 'Parent')
+        );
+    }
+
+    public function testGetEditLinkForDataObjectException()
+    {
+        $root = $this->objFromFixture(BelongsToModelAdmin::class, 'root');
+        $nested = $this->objFromFixture(NestedObject::class, 'redHerringOne');
+
+        $this->expectException(LogicException::class);
+        $this->assertNull($root->getCMSEditLinkForManagedDataObject($nested, 'AnotherOfTheSameClass'));
+    }
+
+    public function testCMSEditLink()
+    {
+        $root = $this->objFromFixture(BelongsToModelAdmin::class, 'root');
+        $basicNested = $this->objFromFixture(BasicNestedObject::class, 'one');
+        $nested = $this->objFromFixture(NestedObject::class, 'one');
+        $polymorphic = $this->objFromFixture(PolymorphicNestedObject::class, 'one');
+
+        $rootUrl = "http://localhost/admin/cms-edit-test/belongsHere/EditForm/field/belongsHere/item/$root->ID";
+        $this->assertSame($rootUrl, $root->CMSEditLink());
+        $this->assertSame(
+            "$rootUrl/ItemEditForm/field/BasicNested/item/$basicNested->ID",
+            $basicNested->CMSEditLink()
+        );
+        $this->assertSame(
+            "$rootUrl/ItemEditForm/field/Nested/item/$nested->ID",
+            $nested->CMSEditLink()
+        );
+        $this->assertSame(
+            "$rootUrl/ItemEditForm/field/PolyMorphic/item/$polymorphic->ID",
+            $polymorphic->CMSEditLink()
+        );
+    }
+}
diff --git a/tests/php/CMSEditLinkExtensionTest.yml b/tests/php/CMSEditLinkExtensionTest.yml
new file mode 100644
index 000000000..69a9a0ca3
--- /dev/null
+++ b/tests/php/CMSEditLinkExtensionTest.yml
@@ -0,0 +1,33 @@
+SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\BasicNestedObject:
+  one:
+    Name: 'some name'
+
+SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\PolymorphicNestedObject:
+  one:
+    Name: 'some name'
+
+SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\NestedObject:
+  one:
+    Name: 'some name'
+  redHerringOne:
+    Name: 'This exists so there is a record in an edge-case relation'
+  redHerringTwo:
+    Name: 'This exists so there is a record in an edge-case relation'
+
+SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\BelongsToModelAdmin:
+  redHerringOne:
+    Name: 'This exists so we know it doesnt just grab the first record'
+  root:
+    Name: 'this is the record we care about'
+    Nested:
+      - '=>SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\NestedObject.one'
+    ArbitraryRelation:
+      - '=>SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\NestedObject.redHerringOne'
+    AnotherArbitraryRelation:
+      - '=>SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\NestedObject.redHerringTwo'
+    BasicNested:
+      - '=>SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\BasicNestedObject.one'
+    PolyMorphic:
+      - '=>SilverStripe\Admin\Tests\CMSEditLinkExtensionTest\PolymorphicNestedObject.one'
+  redHerringTwo:
+    Name: 'This exists so we know it doesnt just grab the last record'
diff --git a/tests/php/CMSEditLinkExtensionTest/BasicNestedObject.php b/tests/php/CMSEditLinkExtensionTest/BasicNestedObject.php
new file mode 100644
index 000000000..310a13b7e
--- /dev/null
+++ b/tests/php/CMSEditLinkExtensionTest/BasicNestedObject.php
@@ -0,0 +1,26 @@
+<?php
+
+namespace SilverStripe\Admin\Tests\CMSEditLinkExtensionTest;
+
+use SilverStripe\Admin\CMSEditLinkExtension;
+use SilverStripe\Dev\TestOnly;
+use SilverStripe\ORM\DataObject;
+
+class BasicNestedObject extends DataObject implements TestOnly
+{
+    private static $table_name = 'CMSEditLinkTest_BasicNestedObject';
+
+    private static $cms_edit_owner = 'Parent';
+
+    private static $db = [
+        'Name' => 'Varchar(255)',
+    ];
+
+    private static $has_one = [
+        'Parent' => BelongsToModelAdmin::class,
+    ];
+
+    private static $extensions = [
+        CMSEditLinkExtension::class,
+    ];
+}
diff --git a/tests/php/CMSEditLinkExtensionTest/BelongsToModelAdmin.php b/tests/php/CMSEditLinkExtensionTest/BelongsToModelAdmin.php
new file mode 100644
index 000000000..e8d6880bc
--- /dev/null
+++ b/tests/php/CMSEditLinkExtensionTest/BelongsToModelAdmin.php
@@ -0,0 +1,37 @@
+<?php
+
+namespace SilverStripe\Admin\Tests\CMSEditLinkExtensionTest;
+
+use SilverStripe\Admin\CMSEditLinkExtension;
+use SilverStripe\Dev\TestOnly;
+use SilverStripe\ORM\DataObject;
+
+class BelongsToModelAdmin extends DataObject implements TestOnly
+{
+    private static $table_name = 'CMSEditLinkTest_BelongsToModelAdmin';
+
+    private static $cms_edit_owner = CMSEditModelAdmin::class;
+
+    private static $db = [
+        'Name' => 'Varchar(255)',
+    ];
+
+    private static $has_many = [
+        'ArbitraryRelation' => NestedObject::class,
+        'Nested' => NestedObject::class . '.Parent',
+        'AnotherArbitraryRelation' => NestedObject::class . '.AnotherOfTheSameClass',
+        'BasicNested' => BasicNestedObject::class,
+        'PolyMorphic' => PolymorphicNestedObject::class,
+    ];
+
+    public function getCMSFields()
+    {
+        $fields = parent::getCMSFields();
+        $fields->removeByName(['ArbitraryRelation', 'AnotherArbitraryRelation']);
+        return $fields;
+    }
+
+    private static $extensions = [
+        CMSEditLinkExtension::class,
+    ];
+}
diff --git a/tests/php/CMSEditLinkExtensionTest/CMSEditModelAdmin.php b/tests/php/CMSEditLinkExtensionTest/CMSEditModelAdmin.php
new file mode 100644
index 000000000..f19362cd6
--- /dev/null
+++ b/tests/php/CMSEditLinkExtensionTest/CMSEditModelAdmin.php
@@ -0,0 +1,15 @@
+<?php
+
+namespace SilverStripe\Admin\Tests\CMSEditLinkExtensionTest;
+
+use SilverStripe\Admin\ModelAdmin;
+use SilverStripe\Dev\TestOnly;
+
+class CMSEditModelAdmin extends ModelAdmin implements TestOnly
+{
+    private static $url_segment = 'cms-edit-test';
+
+    private static $managed_models = [
+        'belongsHere' => BelongsToModelAdmin::class,
+    ];
+}
diff --git a/tests/php/CMSEditLinkExtensionTest/NestedObject.php b/tests/php/CMSEditLinkExtensionTest/NestedObject.php
new file mode 100644
index 000000000..223fa6f30
--- /dev/null
+++ b/tests/php/CMSEditLinkExtensionTest/NestedObject.php
@@ -0,0 +1,28 @@
+<?php
+
+namespace SilverStripe\Admin\Tests\CMSEditLinkExtensionTest;
+
+use SilverStripe\Admin\CMSEditLinkExtension;
+use SilverStripe\Dev\TestOnly;
+use SilverStripe\ORM\DataObject;
+
+class NestedObject extends DataObject implements TestOnly
+{
+    private static $table_name = 'CMSEditLinkTest_NestedObject';
+
+    private static $cms_edit_owner = 'Parent';
+
+    private static $db = [
+        'Name' => 'Varchar(255)',
+    ];
+
+    private static $has_one = [
+        'Parent' => BelongsToModelAdmin::class,
+        'AnotherOfTheSameClass' => BelongsToModelAdmin::class,
+        'ThirdOne' => BelongsToModelAdmin::class,
+    ];
+
+    private static $extensions = [
+        CMSEditLinkExtension::class,
+    ];
+}
diff --git a/tests/php/CMSEditLinkExtensionTest/PolymorphicNestedObject.php b/tests/php/CMSEditLinkExtensionTest/PolymorphicNestedObject.php
new file mode 100644
index 000000000..a49917e73
--- /dev/null
+++ b/tests/php/CMSEditLinkExtensionTest/PolymorphicNestedObject.php
@@ -0,0 +1,26 @@
+<?php
+
+namespace SilverStripe\Admin\Tests\CMSEditLinkExtensionTest;
+
+use SilverStripe\Admin\CMSEditLinkExtension;
+use SilverStripe\Dev\TestOnly;
+use SilverStripe\ORM\DataObject;
+
+class PolymorphicNestedObject extends DataObject implements TestOnly
+{
+    private static $table_name = 'CMSEditLinkTest_PolymorphicNestedObject';
+
+    private static $cms_edit_owner = 'Parent';
+
+    private static $db = [
+        'Name' => 'Varchar(255)',
+    ];
+
+    private static $has_one = [
+        'Parent' => DataObject::class,
+    ];
+
+    private static $extensions = [
+        CMSEditLinkExtension::class,
+    ];
+}
diff --git a/tests/php/ModelAdminTest.php b/tests/php/ModelAdminTest.php
index 6fa577f6e..9fe6db7c4 100644
--- a/tests/php/ModelAdminTest.php
+++ b/tests/php/ModelAdminTest.php
@@ -323,20 +323,20 @@ public function testLinkForInvalidModelTab()
         $admin->getLinkForModelTab(ContactSubclass::class);
     }
 
-    public function testGetEditLinkForManagedDataObject()
+    public function testGetCMSEditLinkForManagedDataObject()
     {
         $admin = new ModelAdminTest\MultiModelAdmin();
         $contact = $this->objFromFixture(Contact::class, 'sam');
         $sanitisedContact = $this->sanitiseClassName(Contact::class);
         $this->assertEquals(
             "admin/multi/$sanitisedContact/EditForm/field/$sanitisedContact/item/$contact->ID",
-            $admin->getEditLinkForManagedDataObject($contact)
+            $admin->getCMSEditLinkForManagedDataObject($contact)
         );
 
         $contact2 = $this->objFromFixture(ContactSubclass::class, 'danie');
         $this->assertEquals(
             "admin/multi/$sanitisedContact/EditForm/field/$sanitisedContact/item/$contact2->ID",
-            $admin->getEditLinkForManagedDataObject($contact2)
+            $admin->getCMSEditLinkForManagedDataObject($contact2)
         );
 
         // Note: It uses the first tab that has this class - we're using
@@ -344,7 +344,7 @@ public function testGetEditLinkForManagedDataObject()
         $player = $this->objFromFixture(Player::class, 'amy');
         $this->assertEquals(
             "admin/multi/Player/EditForm/field/Player/item/$player->ID",
-            $admin->getEditLinkForManagedDataObject($player)
+            $admin->getCMSEditLinkForManagedDataObject($player)
         );
     }