Theming: Invert app icon in favicon for bright backgrounds

fixes #5650

Signed-off-by: Julius Härtl <jus@bitgrid.net>

1 files changed, 11 insertions, 0 deletions

diff --git a/apps/theming/lib/IconBuilder.php b/apps/theming/lib/IconBuilder.php
index 5d1c58e93f2..d0e26e110fc 100644
--- a/apps/theming/lib/IconBuilder.php
+++ b/apps/theming/lib/IconBuilder.php
@@ -145,6 +145,17 @@ class IconBuilder {
 			$appIconFile->setResolution($resX, $resY);
 			$appIconFile->setBackgroundColor(new ImagickPixel('transparent'));
 			$appIconFile->readImageBlob($svg);
+
+			/**
+			 * invert app icons for bright primary colors
+			 * the default nextcloud logo will not be inverted to black
+			 */
+			if ($this->util->invertTextColor($color)
+				&& !$appIcon instanceof ISimpleFile
+				&& $app !== "core"
+			) {
+				$appIconFile->negateImage(false);
+			}
 			$appIconFile->scaleImage(512, 512, true);
 		} else {
 			$appIconFile = new Imagick();