<?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\LanguageModel;

/**
 * This is an abstract LanguageModel task that implements basic
 * goodies for downstream tasks
 * @since 28.0.
 * @template T of ILanguageModelProvider
 * @template-implements ILanguageModelTask<T>
 */
abstract class AbstractLanguageModelTask implements ILanguageModelTask {
	protected ?int $id = null;
	protected ?string $output = null;

	/**
	 * @psalm-var ILanguageModelTask::STATUS_*
	 */
	protected int $status = ILanguageModelTask::STATUS_UNKNOWN;

	/**
	 * @param string $input
	 * @param string $appId
	 * @param string|null $userId
	 * @param string $identifier An arbitrary identifier for this task. max length: 255 chars
	 * @since 27.1.0
	 */
	final public function __construct(
		protected string $input,
		protected string $appId,
		protected ?string $userId,
		protected string $identifier = '',
	) {
	}

	/**
	 * @return string
	 * @since 27.1.0
	 */
	abstract public function getType(): string;

	/**
	 * @return string|null
	 * @since 27.1.0
	 */
	final public function getOutput(): ?string {
		return $this->output;
	}

	/**
	 * @param string|null $output
	 * @since 27.1.0
	 */
	final public function setOutput(?string $output): void {
		$this->output = $output;
	}

	/**
	 * @psalm-return ILanguageModelTask::STATUS_*
	 * @since 27.1.0
	 */
	final public function getStatus(): int {
		return $this->status;
	}

	/**
	 * @psalm-param ILanguageModelTask::STATUS_* $status
	 * @since 27.1.0
	 */
	final public function setStatus(int $status): void {
		$this->status = $status;
	}

	/**
	 * @return int|null
	 * @since 27.1.0
	 */
	final public function getId(): ?int {
		return $this->id;
	}

	/**
	 * @param int|null $id
	 * @since 27.1.0
	 */
	final public function setId(?int $id): void {
		$this->id = $id;
	}

	/**
	 * @return string
	 * @since 27.1.0
	 */
	final public function getInput(): string {
		return $this->input;
	}

	/**
	 * @return string
	 * @since 27.1.0
	 */
	final public function getAppId(): string {
		return $this->appId;
	}

	/**
	 * @return string
	 * @since 27.1.0
	 */
	final public function getIdentifier(): string {
		return $this->identifier;
	}

	/**
	 * @return string|null
	 * @since 27.1.0
	 */
	final public function getUserId(): ?string {
		return $this->userId;
	}

	/**
	 * @return array
	 * @since 27.1.0
	 */
	public function jsonSerialize() {
		return [
			'id' => $this->getId(),
			'type' => $this->getType(),
			'status' => $this->getStatus(),
			'userId' => $this->getUserId(),
			'appId' => $this->getAppId(),
			'input' => $this->getInput(),
			'output' => $this->getOutput(),
			'identifier' => $this->getIdentifier(),
		];
	}

	/**
	 * @param string $type
	 * @param string $input
	 * @param string|null $userId
	 * @param string $appId
	 * @param string $identifier
	 * @return ILanguageModelTask
	 * @throws \InvalidArgumentException
	 * @since 27.1.0
	 */
	final public static function factory(string $type, string $input, ?string $userId, string $appId, string $identifier = ''): ILanguageModelTask {
		if (!in_array($type, array_keys(self::TYPES))) {
			throw new \InvalidArgumentException('Unknown task type');
		}
		return new (ILanguageModelTask::TYPES[$type])($input, $appId, $userId, $identifier);
	}
}