<?php

declare(strict_types=1);

/**
 * @copyright Copyright (c) 2023 Marcel Klehr <mklehr@gmx.net>
 *
 * @author Marcel Klehr <mklehr@gmx.net>
 *
 * @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 OCP\TextToImage;

use OCP\DB\Exception;
use OCP\PreConditionNotMetException;
use OCP\TextToImage\Exception\TaskFailureException;
use OCP\TextToImage\Exception\TaskNotFoundException;
use RuntimeException;

/**
 * API surface for apps interacting with and making use of TextToImage providers
 * without knowing which providers are installed
 * @since 28.0.0
 */
interface IManager {
	/**
	 * @since 28.0.0
	 */
	public function hasProviders(): bool;

	/**
	 * @since 28.0.0
	 * @return list<IProvider>
	 */
	public function getProviders(): array;

	/**
	 * @param Task $task The task to run
	 * @throws PreConditionNotMetException If no or not the requested provider was registered but this method was still called
	 * @throws TaskFailureException If something else failed. When this is thrown task status was already set to failure.
	 * @since 28.0.0
	 */
	public function runTask(Task $task): void;

	/**
	 * Will schedule a TextToImage process in the background. The result will become available
	 * with the \OCP\TextToImage\TaskSuccessfulEvent
	 * If inference fails a \OCP\TextToImage\Events\TaskFailedEvent will be dispatched instead
	 *
	 * @param Task $task The task to schedule
	 * @throws PreConditionNotMetException If no provider was registered but this method was still called
	 * @throws Exception If there was a problem inserting the task into the database
	 * @since 28.0.0
	 */
	public function scheduleTask(Task $task) : void;

	/**
	 * @throws Exception if there was a problem inserting the task into the database
	 * @throws PreConditionNotMetException if no provider is registered
	 * @throws TaskFailureException If the task run failed
	 * @since 28.0.0
	 */
	public function runOrScheduleTask(Task $task) : void;

	/**
	 * Delete a task that has been scheduled before
	 *
	 * @param Task $task The task to delete
	 * @since 28.0.0
	 */
	public function deleteTask(Task $task): void;

	/**
	 * @param int $id The id of the task
	 * @return Task
	 * @throws RuntimeException If the query failed
	 * @throws TaskNotFoundException If the task could not be found
	 * @since 28.0.0
	 */
	public function getTask(int $id): Task;

	/**
	 * @param int $id The id of the task
	 * @param string|null $userId The user id that scheduled the task
	 * @return Task
	 * @throws RuntimeException If the query failed
	 * @throws TaskNotFoundException If the task could not be found
	 * @since 28.0.0
	 */
	public function getUserTask(int $id, ?string $userId): Task;

	/**
	 * @param ?string $userId
	 * @param string $appId
	 * @param string|null $identifier
	 * @return Task[]
	 * @since 28.0.0
	 * @throws RuntimeException If the query failed
	 */
	public function getUserTasksByApp(?string $userId, string $appId, ?string $identifier = null): array;
}