htmlviewer-directediting: HTML rendering in Nextcloud iOS app

- htmlviewer: IEditor + Bridge + srcdoc iframe template + content controller
- text app: open() bridges text/html to htmlviewer template
- idempotent install.sh for re-deployment after app updates
- iPhone-tested 2026-09-11

patches/htmlviewer/HtmlDirectEditor.php

@@ -0,0 +1,88 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2026 HtmlViewer / patch by Hermes Agent
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ *
+ * DirectEditing editor for text/html so the Nextcloud iOS/Android apps
+ * open HTML files in an embedded WebView instead of falling back to
+ * QuickLook source display.
+ */
+
+namespace OCA\HtmlViewer\DirectEditing;
+
+use OCA\HtmlViewer\AppInfo\Application;
+use OCP\AppFramework\Http\NotFoundResponse;
+use OCP\AppFramework\Http\Response;
+use OCP\AppFramework\Http\TemplateResponse;
+use OCP\DirectEditing\IEditor;
+use OCP\DirectEditing\IToken;
+use OCP\Files\InvalidPathException;
+use OCP\Files\NotFoundException;
+use OCP\IL10N;
+use OCP\IURLGenerator;
+
+class HtmlDirectEditor implements IEditor {
+
+	public function __construct(
+		private IL10N $l10n,
+		private IURLGenerator $urlGenerator,
+	) {
+	}
+
+	#[\Override]
+	public function getId(): string {
+		return Application::APP_ID;
+	}
+
+	#[\Override]
+	public function getName(): string {
+		return $this->l10n->t('HTML Viewer');
+	}
+
+	#[\Override]
+	public function getMimetypes(): array {
+		return [
+			'text/html',
+		];
+	}
+
+	#[\Override]
+	public function getMimetypesOptional(): array {
+		return [];
+	}
+
+	#[\Override]
+	public function getCreators(): array {
+		return [];
+	}
+
+	#[\Override]
+	public function isSecure(): bool {
+		return false;
+	}
+
+	#[\Override]
+	public function open(IToken $token): Response {
+		$token->useTokenScope();
+
+		try {
+			$file = $token->getFile();
+
+			return new TemplateResponse(
+				Application::APP_ID,
+				'directEditing',
+				[
+					'fileId' => $file->getId(),
+					'fileName' => $file->getName(),
+					'fileContent' => $file->getContent(),
+				],
+				'base'
+			);
+		} catch (InvalidPathException|NotFoundException) {
+			return new NotFoundResponse();
+		}
+	}
+}