<?php

namespace OCA\UPschooling\Service;

use Aryess\PhpMatrixSdk\Exceptions\MatrixException;
use Aryess\PhpMatrixSdk\Exceptions\MatrixHttpLibException;
use Aryess\PhpMatrixSdk\Exceptions\MatrixRequestException;
use Exception;
use OCA\UPschooling\Db\MatrixTicket;
use OCA\UPschooling\Db\MatrixUser;
use OCA\UPschooling\Db\TicketMapper;
use OCA\UPschooling\Db\UserMapper;
use OCA\UPschooling\Exceptions\RoomNotFoundException;
use OCP\AppFramework\Db\DoesNotExistException;
use OCP\AppFramework\Db\MultipleObjectsReturnedException;

class TicketService {

	/** @var MatrixService */
	private $matrix;

	/** @var TicketMapper */
	private $ticketMapper;

	/** @var UserMapper */
	private $userMapper;

	public function __construct(MatrixService $matrix, TicketMapper $ticketMapper, UserMapper $userMapper) {
		$this->matrix = $matrix;
		$this->ticketMapper = $ticketMapper;
		$this->userMapper = $userMapper;
	}

	public function findAll(string $userId): array {
		$dbTickets = $this->ticketMapper->findAll($this->getOrCreateUser($userId));
		return array_map(function ($ticket) { return $this->resolveTicket($ticket); }, $dbTickets);
	}

	public function find($id, $userId): array {
		return $this->resolveTicket($this->ticketMapper->find($id, $this->getOrCreateUser($userId)));
	}

	public function create($title, $content, $userId): array {
		$matrixUser = $this->getOrCreateUser($userId);
		// FIXME: room must be joined on the remote support-platform Nextcloud
		$roomId = $this->matrix->createRoom();
		$this->matrix->setProperty($roomId, "upschooling.ticket", array(
			// id is to be set from the remote support-platform Nextcloud
			"title" => $title,
			"description" => $content,
		));
		$ticket = new MatrixTicket();
		$ticket->setMatrixRoom($roomId);
		$ticket->setMatrixAssistedUser($matrixUser->getMatrixUser());
		$ticket->setStatus("open");
		$ticket->setVersion(1);
		return $this->resolveTicket($this->ticketMapper->insert($ticket));
	}

	public function update($id, $title, $content, $userId) {
		throw new Exception("Not implemented");
	}

	public function delete($id, $userId) {
		throw new Exception("Not implemented");
	}

	/**
	 * @param MatrixTicket $ticket the database object.
	 * @return array a JSON serializable representation of the resolved ticket, for the frontend.
	 */
	private function resolveTicket(MatrixTicket $ticket): array
	{
		try {
			$matrixTicketContent = $this->matrix->getProperty($ticket->getMatrixRoom(), "upschooling.ticket");
			$ticketId = array_get($matrixTicketContent, "id", $ticket->getId());
			$title = array_get($matrixTicketContent, "title", "Untitled");
			$description = array_get($matrixTicketContent, "description", "");
			$lastModified = $this->matrix->getLastEventDate($ticket->getMatrixRoom());
			return array(
				'ticketId' => $ticketId,
				'status' => $ticket->getStatus(),
				'lastModified' => $lastModified,
				'title' => $title,
				'description' => $description,
			);
		} catch (MatrixException | RoomNotFoundException $e) {
			return array(
				'ticketId' => $ticket->getId(),
				'status' => 'error',
			);
		}
	}

	/**
	 * @param $userId string Nextcloud user id
	 * @throws MatrixException
	 * @throws MatrixHttpLibException
	 * @throws MatrixRequestException
	 * @throws MultipleObjectsReturnedException
	 * @throws \OCP\DB\Exception
	 */
	private function getOrCreateUser(string $userId): MatrixUser
	{
		try {
			return $this->userMapper->find($userId);
		} catch (DoesNotExistException $e) {
			$matrixUser = $this->matrix->registerNewUser();
			$matrixUser->setUserId($userId);
			$this->userMapper->insert($matrixUser);
			return $matrixUser;
		}
	}
}