1 files changed, 188 insertions, 0 deletions
diff --git a/apps/theming/lib/Service/ThemesService.php b/apps/theming/lib/Service/ThemesService.php
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+++ b/apps/theming/lib/Service/ThemesService.php
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+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2022 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OCA\Theming\Service;
+
+use OCA\Theming\AppInfo\Application;
+use OCA\Theming\ITheme;
+use OCA\Theming\Themes\DarkHighContrastTheme;
+use OCA\Theming\Themes\DarkTheme;
+use OCA\Theming\Themes\DefaultTheme;
+use OCA\Theming\Themes\DyslexiaFont;
+use OCA\Theming\Themes\HighContrastTheme;
+use OCA\Theming\Themes\LightTheme;
+use OCP\IConfig;
+use OCP\IUser;
+use OCP\IUserSession;
+use Psr\Log\LoggerInterface;
+
+class ThemesService {
+	/** @var ITheme[] */
+	private array $themesProviders;
+
+	public function __construct(
+		private IUserSession $userSession,
+		private IConfig $config,
+		private LoggerInterface $logger,
+		private DefaultTheme $defaultTheme,
+		LightTheme $lightTheme,
+		private DarkTheme $darkTheme,
+		HighContrastTheme $highContrastTheme,
+		DarkHighContrastTheme $darkHighContrastTheme,
+		DyslexiaFont $dyslexiaFont,
+	) {
+
+		// Register themes
+		$this->themesProviders = [
+			$defaultTheme->getId() => $defaultTheme,
+			$lightTheme->getId() => $lightTheme,
+			$darkTheme->getId() => $darkTheme,
+			$highContrastTheme->getId() => $highContrastTheme,
+			$darkHighContrastTheme->getId() => $darkHighContrastTheme,
+			$dyslexiaFont->getId() => $dyslexiaFont,
+		];
+	}
+
+	/**
+	 * Get the list of all registered themes
+	 *
+	 * @return ITheme[]
+	 */
+	public function getThemes(): array {
+		// Enforced theme if configured
+		$enforcedTheme = $this->config->getSystemValueString('enforce_theme', '');
+		if ($enforcedTheme !== '') {
+			if (!isset($this->themesProviders[$enforcedTheme])) {
+				$this->logger->error('Enforced theme not found', ['theme' => $enforcedTheme]);
+				return $this->themesProviders;
+			}
+
+			$defaultTheme = $this->themesProviders[$this->defaultTheme->getId()];
+			$darkTheme = $this->themesProviders[$this->darkTheme->getId()];
+			$theme = $this->themesProviders[$enforcedTheme];
+			return [
+				// Leave the default theme as a fallback
+				$defaultTheme->getId() => $defaultTheme,
+				// Make sure we also have the dark theme to allow apps
+				// to scope sections of their UI to the dark theme
+				$darkTheme->getId() => $darkTheme,
+				// Finally, the enforced theme
+				$theme->getId() => $theme,
+			];
+		}
+
+		return $this->themesProviders;
+	}
+
+	/**
+	 * Enable a theme for the logged-in user
+	 *
+	 * @param ITheme $theme the theme to enable
+	 * @return string[] the enabled themes
+	 */
+	public function enableTheme(ITheme $theme): array {
+		$themesIds = $this->getEnabledThemes();
+
+		// If already enabled, ignore
+		if (in_array($theme->getId(), $themesIds)) {
+			return $themesIds;
+		}
+
+		/** @var ITheme[] */
+		$themes = array_filter(array_map(function ($themeId) {
+			return $this->getThemes()[$themeId];
+		}, $themesIds));
+
+		// Filtering all themes with the same type
+		$filteredThemes = array_filter($themes, function (ITheme $t) use ($theme) {
+			return $theme->getType() === $t->getType();
+		});
+
+		// Retrieve IDs only
+		/** @var string[] */
+		$filteredThemesIds = array_map(function (ITheme $t) {
+			return $t->getId();
+		}, array_values($filteredThemes));
+
+		$enabledThemes = array_merge(array_diff($themesIds, $filteredThemesIds), [$theme->getId()]);
+		$this->setEnabledThemes($enabledThemes);
+
+		return $enabledThemes;
+	}
+
+	/**
+	 * Disable a theme for the logged-in user
+	 *
+	 * @param ITheme $theme the theme to disable
+	 * @return string[] the enabled themes
+	 */
+	public function disableTheme(ITheme $theme): array {
+		$themesIds = $this->getEnabledThemes();
+
+		// If enabled, removing it
+		if (in_array($theme->getId(), $themesIds)) {
+			$enabledThemes = array_diff($themesIds, [$theme->getId()]);
+			$this->setEnabledThemes($enabledThemes);
+			return $enabledThemes;
+		}
+
+		return $themesIds;
+	}
+
+	/**
+	 * Check whether a theme is enabled or not
+	 * for the logged-in user
+	 *
+	 * @return bool
+	 */
+	public function isEnabled(ITheme $theme): bool {
+		$user = $this->userSession->getUser();
+		if ($user instanceof IUser) {
+			// Using keys as it's faster
+			$themes = $this->getEnabledThemes();
+			return in_array($theme->getId(), $themes);
+		}
+		return false;
+	}
+
+	/**
+	 * Get the list of all enabled themes IDs for the current user.
+	 *
+	 * @return string[]
+	 */
+	public function getEnabledThemes(): array {
+		$enforcedTheme = $this->config->getSystemValueString('enforce_theme', '');
+		$user = $this->userSession->getUser();
+		if ($user === null) {
+			if ($enforcedTheme !== '') {
+				return [$enforcedTheme];
+			}
+			return [];
+		}
+
+		$enabledThemes = json_decode($this->config->getUserValue($user->getUID(), Application::APP_ID, 'enabled-themes', '["default"]'));
+		if ($enforcedTheme !== '') {
+			return array_merge([$enforcedTheme], $enabledThemes);
+		}
+
+		try {
+			return $enabledThemes;
+		} catch (\Exception $e) {
+			return [];
+		}
+	}
+
+	/**
+	 * Set the list of enabled themes
+	 * for the logged-in user
+	 *
+	 * @param string[] $themes the list of enabled themes IDs
+	 */
+	private function setEnabledThemes(array $themes): void {
+		$user = $this->userSession->getUser();
+		$this->config->setUserValue($user->getUID(), Application::APP_ID, 'enabled-themes', json_encode(array_values(array_unique($themes))));
+	}
+}