<?php
namespace Vichan\Service\Media;

use Vichan\Data\{MediaInstallResult, ThumbGenerationResult};
use Vichan\Functions\Metadata;


class FallbackMediaHandler implements MediaHandler {
	use MediaHandlerTrait;

	private string $path;
	private int $width;
	private int $height;
	private string $mime;


	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 ];
	}

	public function __construct(string $default_thumb_path) {
		list($width, $height, $mime) = self::getShape($default_thumb_path);
		$this->path = $default_thumb_path;
		$this->width = $width;
		$this->height = $height;
		$this->mime = $mime;
	}

	public function supportsMime(string $mime): bool {
		return true;
	}

	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->generateThumb(
			$handle,
			$thumb_preferred_out_file_basepath,
			$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 new ThumbGenerationResult(
			$this->path,
			$this->mime,
			\min($this->width, $max_width),
			\min($this->height, $max_height)
		);
	}
}