fix(theming): Adjust dark high contrast to fulfill WCAG 2.1 AAA contrast

Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

2 files changed, 169 insertions, 8 deletions

diff --git a/apps/theming/tests/Themes/AccessibleThemeTestCase.php b/apps/theming/tests/Themes/AccessibleThemeTestCase.php
index fbd0722552d..84121dd41b0 100644
--- a/apps/theming/tests/Themes/AccessibleThemeTestCase.php
+++ b/apps/theming/tests/Themes/AccessibleThemeTestCase.php
@@ -30,7 +30,15 @@ class AccessibleThemeTestCase extends TestCase {
 	protected ITheme $theme;
 	protected Util $util;
 
+	/**
+	 * Set to true to check for WCAG AAA level accessibility
+	 */
+	protected bool $WCAGaaa = false;
+
 	public function dataAccessibilityPairs() {
+		$textContrast = $this->WCAGaaa ? 7.0 : 4.5;
+		$elementContrast = 3.0;
+
 		return [
 			'primary-element on background' => [
 				[
@@ -44,7 +52,7 @@ class AccessibleThemeTestCase extends TestCase {
 					'--color-background-darker',
 					'--color-main-background-blur',
 				],
-				3.0,
+				$elementContrast,
 			],
 			'status color elements on background' => [
 				[
@@ -64,7 +72,18 @@ class AccessibleThemeTestCase extends TestCase {
 					'--color-background-darker',
 					'--color-main-background-blur',
 				],
-				3.0,
+				$elementContrast,
+			],
+			// Those two colors are used for borders which will be `color-main-text` on focussed state, thus need 3:1 contrast to it
+			'success-error-border-colors' => [
+				[
+					'--color-error',
+					'--color-success',
+				],
+				[
+					'--color-main-text',
+				],
+				$elementContrast,
 			],
 			'primary-element-text' => [
 				[
@@ -75,7 +94,7 @@ class AccessibleThemeTestCase extends TestCase {
 					'--color-primary-element',
 					'--color-primary-element-hover',
 				],
-				4.5,
+				$textContrast,
 			],
 			'primary-element-light-text' => [
 				['--color-primary-element-light-text'],
@@ -83,7 +102,7 @@ class AccessibleThemeTestCase extends TestCase {
 					'--color-primary-element-light',
 					'--color-primary-element-light-hover',
 				],
-				4.5,
+				$textContrast,
 			],
 			'main-text' => [
 				['--color-main-text'],
@@ -94,7 +113,7 @@ class AccessibleThemeTestCase extends TestCase {
 					'--color-background-darker',
 					'--color-main-background-blur',
 				],
-				4.5,
+				$textContrast,
 			],
 			'max-contrast-text' => [
 				['--color-text-maxcontrast'],
@@ -103,14 +122,14 @@ class AccessibleThemeTestCase extends TestCase {
 					'--color-background-hover',
 					'--color-background-dark',
 				],
-				4.5,
+				$textContrast,
 			],
 			'max-contrast text-on blur' => [
 				['--color-text-maxcontrast-background-blur'],
 				[
 					'--color-main-background-blur',
 				],
-				4.5,
+				$textContrast,
 			],
 			'status-text' => [
 				[
@@ -125,7 +144,7 @@ class AccessibleThemeTestCase extends TestCase {
 					'--color-background-dark',
 					'--color-main-background-blur',
 				],
-				4.5,
+				$textContrast,
 			],
 		];
 	}
diff --git a/apps/theming/tests/Themes/DarkHighContrastThemeTest.php b/apps/theming/tests/Themes/DarkHighContrastThemeTest.php
new file mode 100644
index 00000000000..d3a357bcfe7
--- /dev/null
+++ b/apps/theming/tests/Themes/DarkHighContrastThemeTest.php
@@ -0,0 +1,142 @@
+<?php
+/**
+ * @copyright Copyright (c) 2022 John Molakvoæ <skjnldsv@protonmail.com>
+ *
+ * @author John Molakvoæ <skjnldsv@protonmail.com>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+namespace OCA\Theming\Tests\Themes;
+
+use OCA\Theming\AppInfo\Application;
+use OCA\Theming\ImageManager;
+use OCA\Theming\ITheme;
+use OCA\Theming\Service\BackgroundService;
+use OCA\Theming\Themes\DarkHighContrastTheme;
+use OCA\Theming\ThemingDefaults;
+use OCA\Theming\Util;
+use OCP\App\IAppManager;
+use OCP\Files\IAppData;
+use OCP\IConfig;
+use OCP\IL10N;
+use OCP\IURLGenerator;
+use OCP\IUserSession;
+use PHPUnit\Framework\MockObject\MockObject;
+
+class DarkHighContrastThemeTest extends AccessibleThemeTestCase {
+	/** @var ThemingDefaults|MockObject */
+	private $themingDefaults;
+	/** @var IUserSession|MockObject */
+	private $userSession;
+	/** @var IURLGenerator|MockObject */
+	private $urlGenerator;
+	/** @var ImageManager|MockObject */
+	private $imageManager;
+	/** @var IConfig|MockObject */
+	private $config;
+	/** @var IL10N|MockObject */
+	private $l10n;
+	/** @var IAppManager|MockObject */
+	private $appManager;
+
+	// !! important: Enable WCAG AAA tests
+	protected bool $WCAGaaa = true;
+
+	protected function setUp(): void {
+		$this->themingDefaults = $this->createMock(ThemingDefaults::class);
+		$this->userSession = $this->createMock(IUserSession::class);
+		$this->urlGenerator = $this->createMock(IURLGenerator::class);
+		$this->imageManager = $this->createMock(ImageManager::class);
+		$this->config = $this->createMock(IConfig::class);
+		$this->l10n = $this->createMock(IL10N::class);
+		$this->appManager = $this->createMock(IAppManager::class);
+
+		$this->util = new Util(
+			$this->config,
+			$this->appManager,
+			$this->createMock(IAppData::class),
+			$this->imageManager
+		);
+
+		$this->themingDefaults
+			->expects($this->any())
+			->method('getColorPrimary')
+			->willReturn('#0082c9');
+
+		$this->themingDefaults
+			->expects($this->any())
+			->method('getDefaultColorPrimary')
+			->willReturn('#0082c9');
+
+		$this->themingDefaults
+			->expects($this->any())
+			->method('getBackground')
+			->willReturn('/apps/' . Application::APP_ID . '/img/background/' . BackgroundService::DEFAULT_BACKGROUND_IMAGE);
+
+		$this->l10n
+			->expects($this->any())
+			->method('t')
+			->willReturnCallback(function ($text, $parameters = []) {
+				return vsprintf($text, $parameters);
+			});
+
+		$this->urlGenerator
+			->expects($this->any())
+			->method('imagePath')
+			->willReturnCallback(function ($app = 'core', $filename = '') {
+				return "/$app/img/$filename";
+			});
+
+		$this->theme = new DarkHighContrastTheme(
+			$this->util,
+			$this->themingDefaults,
+			$this->userSession,
+			$this->urlGenerator,
+			$this->imageManager,
+			$this->config,
+			$this->l10n,
+			$this->appManager,
+		);
+
+		parent::setUp();
+	}
+
+
+	public function testGetId() {
+		$this->assertEquals('dark-highcontrast', $this->theme->getId());
+	}
+
+	public function testGetType() {
+		$this->assertEquals(ITheme::TYPE_THEME, $this->theme->getType());
+	}
+
+	public function testGetTitle() {
+		$this->assertEquals('Dark theme with high contrast mode', $this->theme->getTitle());
+	}
+
+	public function testGetEnableLabel() {
+		$this->assertEquals('Enable dark high contrast mode', $this->theme->getEnableLabel());
+	}
+
+	public function testGetDescription() {
+		$this->assertEquals('Similar to the high contrast mode, but with dark colours.', $this->theme->getDescription());
+	}
+
+	public function testGetMediaQuery() {
+		$this->assertEquals('(prefers-color-scheme: dark) and (prefers-contrast: more)', $this->theme->getMediaQuery());
+	}
+}