Chapter link

migrations/Version20251016124505.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+/**
+ * Auto-generated Migration: Please modify to your needs!
+ */
+final class Version20251016124505 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return '';
+    }
+
+    public function up(Schema $schema): void
+    {
+        // this up() migration is auto-generated, please modify it to your needs
+        $this->addSql('ALTER TABLE chapter ADD linked_by_id INT DEFAULT NULL');
+        $this->addSql('ALTER TABLE chapter ADD CONSTRAINT FK_F981B52E1AE3CFF3 FOREIGN KEY (linked_by_id) REFERENCES chapter (id)');
+        $this->addSql('CREATE INDEX IDX_F981B52E1AE3CFF3 ON chapter (linked_by_id)');
+    }
+
+    public function down(Schema $schema): void
+    {
+        // this down() migration is auto-generated, please modify it to your needs
+        $this->addSql('ALTER TABLE chapter DROP FOREIGN KEY FK_F981B52E1AE3CFF3');
+        $this->addSql('DROP INDEX IDX_F981B52E1AE3CFF3 ON chapter');
+        $this->addSql('ALTER TABLE chapter DROP linked_by_id');
+    }
+}

src/DataFixtures/ChapterFixtures.php

@@ -22,6 +22,7 @@ public function load(ObjectManager $manager): void
 
         $chapter2->setSection($this->getReference(SectionFixtures::SEC_TWO_REFERENCE, Section::class));
         $chapter2->setCategory($this->getReference(CategoryFixtures::CAT_TWO_REFERENCE, Category::class));
+        $chapter2->addLink($chapter1);
 
         $manager->persist($chapter1);
         $manager->persist($chapter2);

src/Entity/Chapter.php

@@ -3,6 +3,8 @@
 namespace App\Entity;
 
 use App\Repository\ChapterRepository;
+use Doctrine\Common\Collections\ArrayCollection;
+use Doctrine\Common\Collections\Collection;
 use Doctrine\ORM\Mapping as ORM;
 
 #[ORM\Entity(repositoryClass: ChapterRepository::class)]
@@ -21,6 +23,20 @@ class Chapter
     #[ORM\JoinColumn(nullable: false)]
     private ?Section $section = null;
 
+    #[ORM\ManyToOne(targetEntity: self::class, inversedBy: 'link')]
+    private ?self $linkedBy = null;
+
+    /**
+     * @var Collection<int, self>
+     */
+    #[ORM\OneToMany(targetEntity: self::class, mappedBy: 'chapter')]
+    private Collection $link;
+
+    public function __construct()
+    {
+        $this->link = new ArrayCollection();
+    }
+
     public function getId(): ?int
     {
         return $this->id;
@@ -49,4 +65,46 @@ public function setSection(?Section $section): static
 
         return $this;
     }
+
+    public function getLinkedBy(): ?self
+    {
+        return $this->linkedBy;
+    }
+
+    public function setLinkedBy(?self $linkedBy): static
+    {
+        $this->linkedBy = $linkedBy;
+
+        return $this;
+    }
+
+    /**
+     * @return Collection<int, self>
+     */
+    public function getLink(): Collection
+    {
+        return $this->link;
+    }
+
+    public function addLink(self $link): static
+    {
+        if (!$this->link->contains($link)) {
+            $this->link->add($link);
+            $link->setLinkedBy($this);
+        }
+
+        return $this;
+    }
+
+    public function removeLink(self $link): static
+    {
+        if ($this->link->removeElement($link)) {
+            // set the owning side to null (unless already changed)
+            if ($link->getLinkedBy() === $this) {
+                $link->setLinkedBy(null);
+            }
+        }
+
+        return $this;
+    }
 }