From bcff3547ea7e99b275df391087bcaaf0d3a02c5d Mon Sep 17 00:00:00 2001
From: Phill Pover <phill@anatid.net>
Date: Mon, 7 Apr 2025 06:59:49 +0100
Subject: [PATCH] Adding unique album validator

---
 backend/src/album/album.entity.ts             |  1 +
 .../middleware/uniqueAlbumTitle.middleware.ts | 32 +++++++++++++++++++
 2 files changed, 33 insertions(+)
 create mode 100644 backend/src/album/middleware/uniqueAlbumTitle.middleware.ts

diff --git a/backend/src/album/album.entity.ts b/backend/src/album/album.entity.ts
index 473a51a..50657b7 100644
--- a/backend/src/album/album.entity.ts
+++ b/backend/src/album/album.entity.ts
@@ -1,5 +1,6 @@
 import { Entity, Column, OneToMany, PrimaryGeneratedColumn } from 'typeorm';
 import { IsNotEmpty, IsString } from 'class-validator';
+import { AlbumTitleUnique } from './middleware/uniqueAlbumTitle.middleware';
 import { Song } from '../song/song.entity';
 
 @Entity()
diff --git a/backend/src/album/middleware/uniqueAlbumTitle.middleware.ts b/backend/src/album/middleware/uniqueAlbumTitle.middleware.ts
new file mode 100644
index 0000000..c69efd1
--- /dev/null
+++ b/backend/src/album/middleware/uniqueAlbumTitle.middleware.ts
@@ -0,0 +1,32 @@
+import { registerDecorator, ValidationOptions, ValidatorConstraint, ValidatorConstraintInterface } from 'class-validator';
+import { Injectable } from '@nestjs/common';
+import { InjectRepository } from '@nestjs/typeorm';
+import { Repository } from 'typeorm';
+
+@ValidatorConstraint({ async: true })
+export class UniqueAlbumTitle implements ValidatorConstraintInterface {
+  constructor(@InjectRepository(Album)
+  private albumRepository: Repository<Album>
+) {}
+
+  validate(albumTitle: string) {
+    return this.albumRepository.findOneBy({
+      where: {
+        id: title
+      }).then((albumTitle) => {
+      return albumTitle === undefined;
+    });
+  }
+}
+
+export function AlbumTitleUnique(validationOptions?: ValidationOptions) {
+  return function (object: object, propertyName: string) {
+    registerDecorator({
+      target: object.constructor,
+      propertyName: propertyName,
+      options: validationOptions,
+      constraints: [],
+      validator: AlbumTitleUnique,
+    });
+  };
+}