MimeMapMediaHandler.php: rework FallbackMediaHandler into a mapper

inc/Service/Media/MimeMapMediaHandler.php

@@ -0,0 +1,91 @@
+<?php
+namespace Vichan\Service\Media;
+
+use Vichan\Data\{MediaInstallResult, ThumbGenerationResult};
+use Vichan\Functions\Metadata;
+
+
+class MimeMapMediaHandler implements MediaHandler {
+	use MediaHandlerTrait;
+
+	/**
+	 * @var callable(string): ?string
+	 */
+	private mixed $mime_mapper;
+
+	private static function getShape(string $file_path) {
+		$ret = \getimagesize($file_path);
+		if ($ret === false) {
+			throw new MediaException("Could not read image sizes of '$file_path'", MediaException::ERR_NO_OPEN);
+		}
+		if ($ret[2] == \IMAGETYPE_UNKNOWN) {
+			throw new \RuntimeException("Error '$file_path' is not an image", MediaException::ERR_BAD_MEDIA_TYPE);
+		}
+
+		$width = $ret[0];
+		$height = $ret[1];
+		$mime = $ret['mime'];
+		return [ $width, $height, $mime ];
+	}
+
+	private function generateThumbImpl(
+		string $source_file_mime,
+		int $max_width,
+		int $max_height
+	): ThumbGenerationResult {
+		$thumb_path = ($this->mime_mapper)($source_file_mime);
+		list($thumb_width, $thumb_height, $thumb_mime) = self::getShape($thumb_path);
+
+		return new ThumbGenerationResult(
+			$thumb_path,
+			$thumb_mime,
+			\min($thumb_width, $max_width),
+			\min($thumb_height, $max_height)
+		);
+	}
+
+	public function __construct(callable $mime_mapper) {
+		$this->mime_mapper = $mime_mapper;
+	}
+
+	public function supportsMime(string $mime): bool {
+		return ($this->mime_mapper)($mime) !== null;
+	}
+
+	public function openHandle(string $file_path, string $file_mime, int $file_kind): mixed {
+		return [ $file_path, $file_mime, $file_kind ];
+	}
+
+	public function closeHandle(mixed $handle) {
+		// No-op
+	}
+
+	public function installMediaAndGenerateThumb(
+		mixed $handle,
+		string $media_preferred_out_file_basepath,
+		string $thumb_preferred_out_file_basepath,
+		int $thumb_max_width,
+		int $thumb_max_height
+	): MediaInstallResult {
+		list($source_file_path, $source_file_mime, $source_file_kind) = $handle;
+		$out_path = $media_preferred_out_file_basepath . '.' . Metadata\mime_to_ext($source_file_mime);
+
+		$this->move_or_link_or_copy($source_file_kind, $source_file_path, $out_path);
+
+		$thumb = $this->generateThumbImpl(
+			$source_file_mime,
+			$thumb_max_width,
+			$thumb_max_height
+		);
+		return new MediaInstallResult($thumb, $out_path);
+	}
+
+	public function generateThumb(
+		mixed $handle,
+		string $preferred_out_file_basepath,
+		int $max_width,
+		int $max_height
+	): ThumbGenerationResult {
+		return $this->generateThumbImpl($handle[1], $max_width, $max_height);
+	}
+}