Implement TimeMap

appinfo/routes.php

@@ -6,5 +6,7 @@ return [
       'requirements' => array('url' => '.+')],
     ['name' => 'timeGate#timeGate', 'url' => '/timegate/{url}', 'verb' => 'GET',
       'requirements' => array('url' => '.+')],
+    ['name' => 'timeMap#timeMap', 'url' => '/timemap/{url}', 'verb' => 'GET',
+      'requirements' => array('url' => '.+')],
   ]
 ];

lib/Controller/TimeMapController.php

@@ -0,0 +1,82 @@
+<?php
+namespace OCA\Memento\Controller;
+
+require_once __DIR__ . '/findMementos.php';
+
+use DateTime;
+
+use OCP\IRequest;
+use OCP\IServerContainer;
+use OCP\IURLGenerator;
+use OCP\AppFramework\Controller;
+use OCP\AppFramework\Http\DataDisplayResponse;
+
+use findMementos;
+
+class TimeMapController extends Controller {
+	private $userFolder;
+	private $URLGenerator;
+
+	public function __construct(
+		$AppName,
+		IRequest $request,
+		$UserId,
+		IServerContainer $serverContainer,
+		IURLGenerator $URLGenerator
+	) {
+		parent::__construct($AppName, $request);
+		$this->userFolder = $serverContainer->getUserFolder($UserId);
+		$this->URLGenerator = $URLGenerator;
+	}
+
+	/**
+	 * @PublicPage
+	 * @NoAdminRequired
+	 * @NoCSRFRequired
+	 */
+	public function timeMap($url) {
+		$matchingMementos = findMementos($this->userFolder, $url);
+
+		// 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..
+		$timeMapUrl = $this->URLGenerator->getAbsoluteUrl("/apps/memento/timemap/$url");
+		$timeGateUrl = $this->URLGenerator->getAbsoluteUrl("/apps/memento/timegate/$url");
+		if (count($matchingMementos) > 0) {
+			$firstDatetime = formatDatetime($matchingMementos[0]['datetime']);
+			$lastDatetime = formatDatetime($matchingMementos[count($matchingMementos)-1]['datetime']);
+		}
+		$links = [
+			// FIXME Our $url param has its duplicate slashes removed, so it looks like 'http:/abc'.
+			"<$url>;rel=\"original\"",
+			"<$timeGateUrl>;rel=\"timegate\"",
+			"<$timeMapUrl>;rel=\"self\";type=\"application/link-format\"" .
+				($firstDatetime && $lastDatetime ? ";from=\"$firstDatetime\";until=\"$lastDatetime\"" : "")
+		];
+		foreach ($matchingMementos as $index => $memento) {
+			$datetime = formatDatetime($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 = $this->URLGenerator->getAbsoluteURL($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 $response;
+	}
+}
+
+function formatDatetime($datetime) {
+	$datetime = new DateTime("@$datetime");
+	$s = $datetime->format("D, d M Y H:i:s") . " GMT";
+	return $s;
+}

lib/Controller/findMementos.php

@@ -5,7 +5,7 @@ use DOMDocument;
 use DateTime;
 
 // Finds HTML files that claim to be a snapshot of the given URL;
-// Returns an array, each item being a file's url + original url + snapshot datetime.
+// Returns an array of each file's url + original url + snapshot datetime, sorted by datetime.
 function findMementos($folder, $url) {
 	// Get all HTML files the user owns.
 	$files = $folder->searchByMime('text/html');
@@ -40,6 +40,10 @@ function findMementos($folder, $url) {
 			continue;
 		}
 	}
+
+	// Sort mementos by their datetime. Oldest first.
+	usort($matchingMementos, function ($m1, $m2) { return $m1['datetime'] <=> $m2['datetime']; });
+
 	return $matchingMementos;
 }