FilePreview abstract class

src/Filesystem/File.php

@@ -242,7 +242,7 @@ public function isResizable(): bool
 
 	/**
 	 * Checks if a preview can be displayed for the file
-	 * in the panel or in the frontend
+	 * in the Panel or in the frontend
 	 */
 	public function isViewable(): bool
 	{

src/Panel/Ui/FilePreview.php

@@ -0,0 +1,88 @@
+<?php
+
+namespace Kirby\Panel\Ui;
+
+use Kirby\Cms\App;
+use Kirby\Cms\File;
+use Kirby\Panel\Ui\FilePreviews\FileDefaultPreview;
+use Kirby\Toolkit\I18n;
+
+/**
+ * Defines a component that implements a file preview
+ *
+ * @package   Kirby Panel
+ * @author    Nico Hoffmann <nico@getkirby.com>
+ * @link      https://getkirby.com
+ * @copyright Bastian Allgeier
+ * @license   https://getkirby.com/license
+ * @since     5.0.0
+ * @internal
+ */
+abstract class FilePreview extends Component
+{
+	public string $component = 'k-file-default-preview';
+
+	public function __construct(
+		public File $file
+	) {
+	}
+
+	/**
+	 * Returns true if this class should
+	 * handle the preview of this file
+	 */
+	abstract public static function accepts(File $file): bool;
+
+	/**
+	 * Returns detail information about the file
+	 */
+	public function details(): array
+	{
+		return [
+			[
+				'title' => I18n::translate('template'),
+				'text'  => $this->file->template() ?? '—'
+			],
+			[
+				'title' => I18n::translate('mime'),
+				'text'  => $this->file->mime()
+			],
+			[
+				'title' => I18n::translate('url'),
+				'text'  => $this->file->id(),
+				'link'  => $this->file->previewUrl()
+			],
+			[
+				'title' => I18n::translate('size'),
+				'text'  => $this->file->niceSize()
+			],
+		];
+	}
+
+	/**
+	 * Returns a file preview instance by going through all
+	 * available handler classes and finding the first that
+	 * accepts the file
+	 */
+	final public static function factory(File $file): static
+	{
+		// get file preview classes providers from plugins
+		$handlers = App::instance()->extensions('filePreviews');
+
+		foreach ($handlers as $handler) {
+			if ($handler::accepts($file) === true) {
+				return new $handler($file);
+			}
+		}
+
+		return new FileDefaultPreview($file);
+	}
+
+	public function props(): array
+	{
+		return [
+			'details' => $this->details(),
+			'url'     => $this->file->previewUrl()
+		];
+	}
+}

tests/Panel/Ui/FilePreviewTest.php

@@ -0,0 +1,107 @@
+<?php
+
+namespace Kirby\Panel\Ui;
+
+use Kirby\Cms\App;
+use Kirby\Cms\File;
+use Kirby\Cms\Page;
+use Kirby\Panel\Ui\FilePreviews\FileDefaultPreview;
+use Kirby\TestCase;
+
+class FileDummyPreview extends FilePreview
+{
+	public static function accepts(File $file): bool
+	{
+		return $file->type() === 'document';
+	}
+}
+
+/**
+ * @coversDefaultClass \Kirby\Panel\Ui\FilePreview
+ * @covers ::__construct
+ */
+class FilePreviewTest extends TestCase
+{
+	/**
+	 * @covers ::factory
+	 */
+	public function testFactory()
+	{
+		$page = new Page(['slug' => 'test']);
+		$file = new File(['filename' => 'test.jpg', 'parent' => $page]);
+
+		$component = FilePreview::factory($file);
+		$this->assertInstanceOf(FileDefaultPreview::class, $component);
+	}
+
+	/**
+	 * @covers ::factory
+	 */
+	public function testFactoryWithCustomHandler()
+	{
+		new App([
+			'roots' => [
+				'index' => '/dev/null'
+			],
+			'filePreviews' => [
+				FileDummyPreview::class
+			]
+		]);
+
+		$page = new Page(['slug' => 'test']);
+
+		$file      = new File(['filename' => 'test.jpg', 'parent' => $page]);
+		$component = FilePreview::factory($file);
+		$this->assertInstanceOf(FileDefaultPreview::class, $component);
+
+		$file      = new File(['filename' => 'test.xls', 'parent' => $page]);
+		$component = FilePreview::factory($file);
+		$this->assertInstanceOf(FileDummyPreview::class, $component);
+	}
+
+	/**
+	 * @covers ::details
+	 * @covers ::props
+	 */
+	public function testProps()
+	{
+		$page      = new Page(['slug' => 'test']);
+		$file      = new File(['filename' => 'test.jpg', 'parent' => $page]);
+		$component = new FileDummyPreview($file);
+
+		$this->assertSame([
+			'details' => [
+				[
+					'title' => 'Template',
+					'text'  => '—',
+		        ],
+		        [
+		            'title' => 'Media Type',
+		            'text'  => 'image/jpeg',
+		        ],
+		        [
+		            'title' => 'Url',
+		            'text'  => 'test/test.jpg',
+		            'link'  => '/test/test.jpg',
+		        ],
+		        [
+		            'title' => 'Size',
+		            'text' => '0 KB',
+		        ]
+			],
+			'url' => '/test/test.jpg'
+		], $component->props());
+	}
+
+	/**
+	 * @covers ::render
+	 */
+	public function testRender()
+	{
+		$page      = new Page(['slug' => 'test']);
+		$file      = new File(['filename' => 'test.jpg', 'parent' => $page]);
+		$component = new FileDummyPreview($file);
+
+		$this->assertSame('k-file-default-preview', $component->render()['component']);
+	}
+}