add provider for Nextcloud's unified search

css/global.scss

@@ -1 +1,2 @@
 @include icon-black-white('notes', 'notes', 1);
+@include icon-black-white('notes-trans', 'notes', 1);

img/notes-trans.svg

@@ -0,0 +1 @@
+<svg width="32" height="32" version="1.0" viewBox="0 0 32 32" xmlns="http://www.w3.org/2000/svg"><path d="m24.484 3.5156c-1.0237 0-2.0471 0.38887-2.8281 1.1699l5.6582 5.6582c1.5621-1.5621 1.5621-4.0961 0-5.6582-0.78105-0.78105-1.8064-1.1699-2.8301-1.1699zm-4.2422 2.584-12.02 12.021 5.6562 5.6562 12.021-12.02-5.6582-5.6582zm-13.436 13.436-2.1211 7.7793 7.7793-2.1211-5.6582-5.6582z" fill="#fff" style="fill-opacity:0.5" /></svg>

lib/AppInfo/Application.php

@@ -20,6 +20,7 @@ class Application extends App implements IBootstrap {
 
 	public function register(IRegistrationContext $context): void {
 		$context->registerCapability(Capabilities::class);
+		$context->registerSearchProvider(SearchProvider::class);
 		$context->registerDashboardWidget(DashboardWidget::class);
 		$context->registerEventListener(
 			BeforeTemplateRenderedEvent::class,

lib/AppInfo/SearchProvider.php

@@ -0,0 +1,84 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OCA\Notes\AppInfo;
+
+use OCA\Notes\Service\Note;
+use OCA\Notes\Service\NotesService;
+use OCA\Notes\Service\Util;
+
+use OCP\IUser;
+use OCP\IURLGenerator;
+use OCP\Search\IProvider;
+use OCP\Search\ISearchQuery;
+use OCP\Search\SearchResult;
+use OCP\Search\SearchResultEntry;
+
+class SearchProvider implements IProvider {
+
+	/** @var Util */
+	private $util;
+	/** @var NotesService */
+	private $notesService;
+	/** @var IURLGenerator */
+	private $url;
+
+	public function __construct(
+		Util $util,
+		NotesService $notesService,
+		IURLGenerator $url
+	) {
+		$this->util = $util;
+		$this->notesService = $notesService;
+		$this->url = $url;
+	}
+
+
+	public function getId(): string {
+		return Application::APP_ID;
+	}
+
+	public function getName(): string {
+		return $this->util->l10n->t('Notes');
+	}
+
+	public function getOrder(string $route, array $routeParameters): int {
+		if (strpos($route, 'files' . '.') === 0) {
+			return 25;
+		} elseif (strpos($route, Application::APP_ID . '.') === 0) {
+			return -1;
+		}
+		return 4;
+	}
+
+	public function search(IUser $user, ISearchQuery $query): SearchResult {
+		$notes = $this->notesService->search($user->getUID(), $query->getTerm());
+		// sort by modified time
+		usort($notes, function (Note $a, Note $b) {
+			return $b->getModified() - $a->getModified();
+		});
+		// create SearchResultEntry from Note
+		$result = array_map(
+			function (Note $note) : SearchResultEntry {
+				$excerpt = $note->getCategory();
+				try {
+					$excerpt = $note->getExcerpt();
+				} catch (\Throwable $e) {
+				}
+				return new SearchResultEntry(
+					'',
+					$note->getTitle(),
+					$excerpt,
+					$this->url->linkToRouteAbsolute('notes.page.index') . 'note/'.$note->getId(),
+					'icon-notes-trans'
+				);
+			},
+			$notes
+		);
+		return SearchResult::complete(
+			$this->getName(),
+			$result
+		);
+	}
+}

lib/Service/NotesService.php

@@ -58,6 +58,39 @@ class NotesService {
 		return $note;
 	}
 
+	public function search(string $userId, string $search) : array {
+		$terms = preg_split('/\s+/', $search);
+		$notes = $this->getAll($userId)['notes'];
+		return array_values(array_filter(
+			$notes,
+			function (Note $note) use ($terms) : bool {
+				return $this->searchTermsInNote($note, $terms);
+			}
+		));
+	}
+	private function searchTermsInNote(Note $note, array $terms) : bool {
+		try {
+			$d = $note->getData();
+			$strings = [ $d['title'], $d['category'], $d['content'] ];
+			foreach ($terms as $term) {
+				if (!$this->searchTermInData($strings, $term)) {
+					return false;
+				}
+			}
+			return true;
+		} catch (\Throwable $e) {
+			return false;
+		}
+	}
+	private function searchTermInData(array $strings, string $term) : bool {
+		foreach ($strings as $str) {
+			if (stripos($str, $term) !== false) {
+				return true;
+			}
+		}
+		return false;
+	}
+
 
 	/**
 	 * @throws \OCP\Files\NotPermittedException