support dark mode for images with alpha channel

1 files changed, 38 insertions, 0 deletions

diff --git a/engine/themes.php b/engine/themes.php
new file mode 100644
index 0000000..839377f
--- /dev/null
+++ b/engine/themes.php
@@ -0,0 +1,38 @@
+<?php
+
+class themes {
+
+    public static array $Themes = [
+        'dark' => [
+            'bg' => 0x222222,
+            // 'alpha' => 0x303132,
+            'alpha' => 0x222222,
+        ],
+        'light' => [
+            'bg' => 0xffffff,
+            // 'alpha' => 0xf2f2f2,
+            'alpha' => 0xffffff,
+        ]
+    ];
+
+    public static function getThemes(): array {
+        return array_keys(self::$Themes);
+    }
+
+    public static function themeExists(string $name): bool {
+        return array_key_exists($name, self::$Themes);
+    }
+
+    public static function getThemeAlphaColorAsRGB(string $name): array {
+        $color = self::$Themes[$name]['alpha'];
+        $r = ($color >> 16) & 0xff;
+        $g = ($color >> 8) & 0xff;
+        $b = $color & 0xff;
+        return [$r, $g, $b];
+    }
+
+    public static function getUserTheme(): string {
+        return ($_COOKIE['theme'] ?? 'auto');
+    }
+
+}
\ No newline at end of file