<?php

declare(strict_types=1);
/**
 * @copyright Copyright (c) 2023 Robin Appelman <robin@icewind.nl>
 *
 * @license GNU AGPL version 3 or any later version
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

namespace OC\Core\Command\Preview;

use OCP\Files\Config\IUserMountCache;
use OCP\Files\IRootFolder;
use OCP\Files\Node;
use OCP\Files\File;
use OCP\Files\NotFoundException;
use OCP\IPreview;
use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputArgument;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;

class Generate extends Command {
	private IRootFolder $rootFolder;
	private IUserMountCache $userMountCache;
	private IPreview $previewManager;

	public function __construct(IRootFolder $rootFolder, IUserMountCache $userMountCache, IPreview $previewManager) {
		$this->rootFolder = $rootFolder;
		$this->userMountCache = $userMountCache;
		$this->previewManager = $previewManager;

		parent::__construct();
	}

	protected function configure() {
		$this
			->setName('preview:generate')
			->setDescription('generate a preview for a file')
			->addArgument("file", InputArgument::REQUIRED, "path or fileid of the file to generate the preview for")
			->addOption("size", "s", InputOption::VALUE_IS_ARRAY | InputOption::VALUE_REQUIRED, "size to generate the preview for in pixels, defaults to 64x64", ["64x64"])
			->addOption("crop", "c", InputOption::VALUE_NONE, "crop the previews instead of maintaining aspect ratio")
			->addOption("mode", "m", InputOption::VALUE_REQUIRED, "mode for generating uncropped previews, 'cover' or 'fill'", IPreview::MODE_FILL);
	}

	protected function execute(InputInterface $input, OutputInterface $output): int {
		$fileInput = $input->getArgument("file");
		$sizes = $input->getOption("size");
		$sizes = array_map(function (string $size) use ($output, &$error) {
			if (str_contains($size, 'x')) {
				$sizeParts = explode('x', $size, 2);
			} else {
				$sizeParts = [$size, $size];
			}
			if (!is_numeric($sizeParts[0]) || !is_numeric($sizeParts[1])) {
				$output->writeln("<error>Invalid size $size</error>");
				return null;
			}

			return array_map("intval", $sizeParts);
		}, $sizes);
		if (in_array(null, $sizes)) {
			return 1;
		}

		$mode = $input->getOption("mode");
		if ($mode !== IPreview::MODE_FILL && $mode !== IPreview::MODE_COVER) {
			$output->writeln("<error>Invalid mode $mode</error>");
			return 1;
		}
		$crop = $input->getOption("crop");
		$file = $this->getFile($fileInput);
		if (!$file) {
			$output->writeln("<error>File $fileInput not found</error>");
			return 1;
		}
		if (!$file instanceof File) {
			$output->writeln("<error>Can't generate previews for folders</error>");
			return 1;
		}

		if (!$this->previewManager->isAvailable($file)) {
			$output->writeln("<error>No preview generator available for file of type" . $file->getMimetype() . "</error>");
			return 1;
		}

		$specifications = array_map(function (array $sizes) use ($crop, $mode) {
			return [
				'width' => $sizes[0],
				'height' => $sizes[1],
				'crop' => $crop,
				'mode' => $mode,
			];
		}, $sizes);

		$this->previewManager->generatePreviews($file, $specifications);
		if (count($specifications) > 1) {
			$output->writeln("generated <info>" . count($specifications) . "</info> previews");
		} else {
			$output->writeln("preview generated");
		}
		return 0;
	}

	private function getFile(string $fileInput): ?Node {
		if (is_numeric($fileInput)) {
			$mounts = $this->userMountCache->getMountsForFileId((int)$fileInput);
			if (!$mounts) {
				return null;
			}
			$mount = $mounts[0];
			$userFolder = $this->rootFolder->getUserFolder($mount->getUser()->getUID());
			$nodes = $userFolder->getById((int)$fileInput);
			if (!$nodes) {
				return null;
			}
			return $nodes[0];
		} else {
			try {
				return $this->rootFolder->get($fileInput);
			} catch (NotFoundException $e) {
				return null;
			}
		}
	}
}