feat: add diff online tool

web/app/controllers/apps/diff_online.php

@@ -0,0 +1,49 @@
+<?php
+requireLib('bootstrap5');
+?>
+
+<?php echoUOJPageHeader(UOJLocale::get('diff online')) ?>
+
+<h1>
+	<?= UOJLocale::get('diff online') ?>
+</h1>
+
+<div class="card">
+	<div class="card-body">
+		<div style="height: 700px" id="diff-editor-container">
+			<div class="border d-flex justify-content-center align-items-center w-100 h-100">
+				<div class="spinner-border text-muted" style="width: 3rem; height: 3rem;"></div>
+			</div>
+		</div>
+	</div>
+	<div class="card-footer bg-transparent text-end">
+		<a href="https://s2oj.github.io/#/user/apps/diff_online" target="_blank">使用教程</a>
+	</div>
+</div>
+
+<script>
+	var div_editor = $('#diff-editor-container');
+
+	require_monaco({}, function() {
+		$(div_editor).html('');
+
+		var originalModel = monaco.editor.createModel("", "text/plain");
+		var modifiedModel = monaco.editor.createModel("", "text/plain");
+
+		var diffEditor = monaco.editor.createDiffEditor(div_editor[0], {
+			originalEditable: true, // for left pane
+			readOnly: false, // for right pane
+			fontSize: "16px",
+			automaticLayout: true,
+		});
+
+		diffEditor.setModel({
+			original: originalModel,
+			modified: modifiedModel,
+		});
+
+		$(div_editor).addClass('border overflow-hidden');
+	});
+</script>
+
+<?php echoUOJPageFooter() ?>

web/app/locale/basic/en.php

@@ -102,4 +102,5 @@ return [
 	'apps' => 'Apps',
 	'image hosting' => 'Image Hosting',
 	'html to markdown' => 'HTML to Markdown',
+	'diff online' => 'Diff Online',
 ];

web/app/locale/basic/zh-cn.php

@@ -102,4 +102,5 @@ return [
 	'apps' => '应用',
 	'image hosting' => '图床',
 	'html to markdown' => 'HTML 转 Markdown',
+	'diff online' => '在线比较',
 ];

web/app/route.php

@@ -96,6 +96,7 @@ Route::group(
 		// Apps
 		Route::any('/apps/image_hosting', '/apps/image_hosting.php');
 		Route::any('/apps/html2markdown', '/apps/html2markdown.php');
+		Route::any('/apps/diff_online', '/apps/diff_online.php');
 	}
 );
 

web/app/views/main-nav.php

@@ -125,6 +125,12 @@ mb-4
 											<?= UOJLocale::get('html to markdown') ?>
 										</a>
 									</li>
+									<li>
+										<a class="dropdown-item" href="<?= HTML::url('/apps/diff_online') ?>">
+											<i class="bi bi-file-earmark-diff"></i>
+											<?= UOJLocale::get('diff online') ?>
+										</a>
+									</li>
 								</ul>
 							</li>
 						<?php endif ?>