Add a CollectionMembership class

lib/Collection.php

@@ -7,9 +7,9 @@ use function Safe\preg_replace;
 class Collection{
 	use Traits\Accessor;
 
+	public int $CollectionId;
 	public string $Name;
 	public string $UrlName;
-	public ?int $SequenceNumber = null;
 	public ?string $Type = null;
 	protected ?string $_Url = null;
 
@@ -28,7 +28,77 @@ class Collection{
 		return $instance;
 	}
 
+	/**
+	 * @throws Exceptions\CollectionNotFoundException
+	 */
+	public static function Get(?int $collectionId): Collection{
+		if($collectionId === null){
+			throw new Exceptions\CollectionNotFoundException();
+		}
+
+		$result = Db::Query('
+				SELECT *
+				from Collections
+				where CollectionId = ?
+			', [$collectionId], Collection::class);
+
+		return $result[0] ?? throw new Exceptions\CollectionNotFoundException();;
+	}
+
 	public function GetSortedName(): string{
 		return preg_replace('/^(the|and|a|)\s/ius', '', $this->Name);
 	}
+
+	/**
+	 * @throws Exceptions\ValidationException
+	 */
+	public function Validate(): void{
+		$error = new Exceptions\ValidationException();
+
+		if(strlen($this->Name) > EBOOKS_MAX_STRING_LENGTH){
+			$error->Add(new Exceptions\StringTooLongException('Collection name: '. $this->Name));
+		}
+
+		if($this->Type !== null && ($this->Type != 'series' && $this->Type != 'set')){
+			$error->Add(new Exceptions\InvalidCollectionTypeException($this->Type));
+		}
+
+		if($error->HasExceptions){
+			throw $error;
+		}
+	}
+
+	/**
+	 * @throws Exceptions\ValidationException
+	 */
+	public function Create(): void{
+		$this->Validate();
+
+		Db::Query('
+			INSERT into Collections (Name, UrlName, Type)
+			values (?,
+				?,
+				?)
+		', [$this->Name, $this->UrlName, $this->Type]);
+		$this->CollectionId = Db::GetLastInsertedId();
+	}
+
+	/**
+	 * @throws Exceptions\ValidationException
+	 */
+	public function GetByUrlNameOrCreate(string $urlName): Collection{
+		$result = Db::Query('
+				SELECT *
+				from Collections
+				where UrlName = ?
+			', [$urlName], Collection::class);
+
+		if(isset($result[0])){
+			return $result[0];
+		}
+		else{
+			$this->Create();
+			return $this;
+		}
+	}
 }