<?php

declare(strict_types=1);

/*
 * Chill is a software for social workers
 *
 * For the full copyright and license information, please view
 * the LICENSE file that was distributed with this source code.
 */

namespace Chill\MainBundle\Pagination;

use Symfony\Component\HttpFoundation\RequestStack;
use Symfony\Component\Routing\RouterInterface;

/**
 * Create paginator instances.
 */
class PaginatorFactory
{
    public const DEFAULT_CURRENT_PAGE_KEY = 'page';

    public const DEFAULT_ITEM_PER_NUMBER_KEY = 'item_per_page';

    public const DEFAULT_PAGE_NUMBER = 1;

    /**
     * the default item per page. This may be overriden by
     * the request or inside the paginator.
     *
     * @var int
     */
    private $itemPerPage;

    /**
     * the request stack.
     *
     * @var RequestStack
     */
    private $requestStack;

    /**
     * the router and generator for url.
     *
     * @var RouterInterface
     */
    private $router;

    public function __construct(
        RequestStack $requestStack,
        RouterInterface $router,
        $itemPerPage = 20
    ) {
        $this->itemPerPage = $itemPerPage;
        $this->requestStack = $requestStack;
        $this->router = $router;
    }

    /**
     * create a paginator instance.
     *
     * The default route and route parameters are the current ones. If set,
     * thos route are overriden.
     *
     * @param int $totalItems
     * @param string|null $route the specific route to use in pages
     * @param array|null $routeParameters the specific route parameters to use in pages
     *
     * @return PaginatorInterface
     */
    public function create(
        $totalItems,
        $route = null,
        ?array $routeParameters = null
    ) {
        return new Paginator(
            $totalItems,
            $this->getCurrentItemsPerPage(),
            $this->getCurrentPageNumber(),
            null === $route ? $this->getCurrentRoute() : $route,
            null === $routeParameters ? $this->getCurrentRouteParameters() :
                 $routeParameters,
            $this->router,
            self::DEFAULT_CURRENT_PAGE_KEY,
            self::DEFAULT_ITEM_PER_NUMBER_KEY
        );
    }

    public function getCurrentItemsPerPage()
    {
        return $this->requestStack
            ->getCurrentRequest()
            ->query
            ->getInt(self::DEFAULT_ITEM_PER_NUMBER_KEY, $this->itemPerPage);
    }

    public function getCurrentPageFirstItemNumber()
    {
        return ($this->getCurrentPageNumber() - 1) *
            $this->getCurrentItemsPerPage();
    }

    /**
     * @return int
     */
    public function getCurrentPageNumber()
    {
        return $this->requestStack
            ->getCurrentRequest()
            ->query
            ->getInt(self::DEFAULT_CURRENT_PAGE_KEY, self::DEFAULT_PAGE_NUMBER);
    }

    protected function getCurrentRoute()
    {
        $request = $this->requestStack->getCurrentRequest();

        return $request->get('_route');
    }

    protected function getCurrentRouteParameters()
    {
        return array_merge(
            $this->router->getContext()->getParameters(),
            // get the route parameters
            $this->requestStack
                ->getCurrentRequest()
                ->attributes->get('_route_params'),
            // get the query parameters
            $this->requestStack
                ->getCurrentRequest()->query->all()
        );
    }
}