<?php
namespace OCA\Memento\Controller;

require_once __DIR__ . '/datetimeConversion.php';
require_once __DIR__ . '/getUrlParameter.php';

use OCP\IRequest;
use OCP\IServerContainer;
use OCP\IURLGenerator;
use OCP\AppFramework\Controller;
use OCP\AppFramework\Http\DataDisplayResponse;

class TimeMapController extends Controller {
	use MementoFinder;

	private $loggedInUserId;
	private $serverContainer;

	public function __construct(
		$AppName,
		IRequest $request,
		$UserId,
		IServerContainer $serverContainer
	) {
		parent::__construct($AppName, $request);
		$this->loggedInUserId = $UserId;
		$this->serverContainer = $serverContainer;
	}

	/**
	 * @NoAdminRequired
	 * @NoCSRFRequired
	 * @PublicPage
	 */
	public function singleUserTimeMap($userId, $url) {
		// XXX workaround, as nextcloud corrupts the $url parameter.
		$routePrefix = "u/$userId/";
		$url = getUrlParameter("{$routePrefix}timemap");

		$matchingMementos = $this->findSingleUserMementosForUrl($userId, $url);

		return $this->makeResponse($url, $matchingMementos, $routePrefix);
	}

	/**
	 * @NoAdminRequired
	 * @NoCSRFRequired
	 * @PublicPage
	 */
	public function allUsersTimeMap($url) {
		$routePrefix = "";
		$url = getUrlParameter("{$routePrefix}timemap");

		$matchingMementos = $this->findAllUsersMementosForUrl($url);

		return $this->makeResponse($url, $matchingMementos, $routePrefix);
	}

	private function makeResponse($url, $matchingMementos, $routePrefix) {
		// Build the list of links.
		// $timeMapUrl = $this->URLGenerator->linkToRouteAbsolute('timeMap#timeMap', [ 'url' => $url ]);
		// $timeGateUrl = $this->URLGenerator->linkToRouteAbsolute('timeGate#timeGate', [ 'url' => $url ]);
		// FIXME ...is linkToRouteAbsolute broken? Hardcoding the path then..
		$URLGenerator = $this->serverContainer->getURLGenerator();
		$timeMapUrl = $URLGenerator->getAbsoluteUrl("/apps/memento/{$routePrefix}timemap/$url");
		$timeGateUrl = $URLGenerator->getAbsoluteUrl("/apps/memento/{$routePrefix}timegate/$url");
		if (count($matchingMementos) > 0) {
			$firstDatetime = datetimeTimestampToString($matchingMementos[0]['datetime']);
			$lastMemento = $matchingMementos[count($matchingMementos)-1];
			$lastDatetime = datetimeTimestampToString($lastMemento['datetime']);
		}
		$links = [
			"<$url>;rel=\"original\"",
			"<$timeGateUrl>;rel=\"timegate\"",
			"<$timeMapUrl>;rel=\"self\";type=\"application/link-format\"" .
				($firstDatetime && $lastDatetime ? ";from=\"$firstDatetime\";until=\"$lastDatetime\"" : "")
		];
		foreach ($matchingMementos as $index => $memento) {
			$datetime = datetimeTimestampToString($memento['datetime']);
			$maybeFirst = $index === 0 ? 'first ' : '';
			$maybeLast = $index === count($matchingMementos)-1 ? 'last ' : '';
			// Make absolute, as the spec says URLs are to be interpreted relative to the *original* url!
			$absoluteMementoUrl = $URLGenerator->getAbsoluteURL($memento['mementoUrl']);
			$links[] = "<$absoluteMementoUrl>"
				. ";rel=\"{$maybeFirst}{$maybeLast}memento\""
				. ";datetime=\"$datetime\"";
		}
		$linksString = implode(",\n", $links);

		$headers = [
			"Content-Type" => "application/link-format"
		];

		$response = new DataDisplayResponse($linksString, 200, $headers);
		return $response;
	}
}