Invert custom views in dark mode

Invert custom view colors (in Y'UV space) if its background isn't dark,
we're in dark mode, and app doesn't target Q.

Change-Id: I74f557315c5e7e91ee7ec01d1535dac40f921524
Fixes: 112767229
Test: send custom notification from pre Q app with black background
Test: send custom notification from pre Q app with white background
Test: send custom notification from pre Q app with green background
Test: send custom notification from Q app with white background

4 files changed, 61 insertions, 5 deletions

diff --git a/packages/SystemUI/res/values/ids.xml b/packages/SystemUI/res/values/ids.xml
index bd34beac7fd6..5e32dd5b2c0e 100644
--- a/packages/SystemUI/res/values/ids.xml
+++ b/packages/SystemUI/res/values/ids.xml
@@ -68,6 +68,7 @@
     <item type="id" name="panel_alpha_animator_tag"/>
     <item type="id" name="panel_alpha_animator_start_tag"/>
     <item type="id" name="panel_alpha_animator_end_tag"/>
+    <item type="id" name="cross_fade_layer_type_changed_tag"/>
 
     <!-- Whether the icon is from a notification for which targetSdk < L -->
     <item type="id" name="icon_is_pre_L"/>
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/CrossFadeHelper.java b/packages/SystemUI/src/com/android/systemui/statusbar/CrossFadeHelper.java
index 6c3e504da8bd..04534ba06d7e 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/CrossFadeHelper.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/CrossFadeHelper.java
@@ -19,6 +19,7 @@ package com.android.systemui.statusbar;
 import android.view.View;
 
 import com.android.systemui.Interpolators;
+import com.android.systemui.R;
 import com.android.systemui.statusbar.notification.stack.StackStateAnimator;
 
 /**
@@ -92,9 +93,15 @@ public class CrossFadeHelper {
 
     private static void updateLayerType(View view, float alpha) {
         if (view.hasOverlappingRendering() && alpha > 0.0f && alpha < 1.0f) {
-            view.setLayerType(View.LAYER_TYPE_HARDWARE, null);
-        } else if (view.getLayerType() == View.LAYER_TYPE_HARDWARE) {
-            view.setLayerType(View.LAYER_TYPE_NONE, null);
+            if (view.getLayerType() != View.LAYER_TYPE_HARDWARE) {
+                view.setLayerType(View.LAYER_TYPE_HARDWARE, null);
+                view.setTag(R.id.cross_fade_layer_type_changed_tag, true);
+            }
+        } else if (view.getLayerType() == View.LAYER_TYPE_HARDWARE
+                && view.getTag(R.id.cross_fade_layer_type_changed_tag) != null) {
+            if (view.getTag(R.id.cross_fade_layer_type_changed_tag) != null) {
+                view.setLayerType(View.LAYER_TYPE_NONE, null);
+            }
         }
     }
 
@@ -114,7 +121,7 @@ public class CrossFadeHelper {
                 .setStartDelay(delay)
                 .setInterpolator(Interpolators.ALPHA_IN)
                 .withEndAction(null);
-        if (view.hasOverlappingRendering()) {
+        if (view.hasOverlappingRendering() && view.getLayerType() != View.LAYER_TYPE_HARDWARE) {
             view.animate().withLayer();
         }
     }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/wrapper/NotificationCustomViewWrapper.java b/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/wrapper/NotificationCustomViewWrapper.java
index db7b4fc189aa..4bdc1705c5ff 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/wrapper/NotificationCustomViewWrapper.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/wrapper/NotificationCustomViewWrapper.java
@@ -17,8 +17,15 @@
 package com.android.systemui.statusbar.notification.row.wrapper;
 
 import android.content.Context;
+import android.content.res.Configuration;
+import android.graphics.Color;
+import android.graphics.ColorMatrix;
+import android.graphics.ColorMatrixColorFilter;
+import android.graphics.Paint;
+import android.os.Build;
 import android.view.View;
 
+import com.android.internal.graphics.ColorUtils;
 import com.android.systemui.R;
 import com.android.systemui.statusbar.notification.row.ExpandableNotificationRow;
 
@@ -42,6 +49,47 @@ public class NotificationCustomViewWrapper extends NotificationViewWrapper {
     }
 
     @Override
+    public void onReinflated() {
+        super.onReinflated();
+
+        Configuration configuration = mView.getResources().getConfiguration();
+        boolean nightMode = (configuration.uiMode & Configuration.UI_MODE_NIGHT_MASK)
+                == Configuration.UI_MODE_NIGHT_YES;
+
+        float[] hsl = new float[] {0f, 0f, 0f};
+        ColorUtils.colorToHSL(mBackgroundColor, hsl);
+        boolean backgroundIsDark = Color.alpha(mBackgroundColor) == 0
+                || hsl[1] == 0 && hsl[2] < 0.5;
+        boolean backgroundHasColor = hsl[1] > 0;
+
+        // Let's invert the notification colors when we're in night mode and
+        // the notification background isn't colorized.
+        if (!backgroundIsDark && !backgroundHasColor && nightMode
+                && mRow.getEntry().targetSdk < Build.VERSION_CODES.Q) {
+            Paint paint = new Paint();
+            ColorMatrix matrix = new ColorMatrix();
+            ColorMatrix tmp = new ColorMatrix();
+            // Inversion should happen on Y'UV space to conseve the colors and
+            // only affect the luminosity.
+            matrix.setRGB2YUV();
+            tmp.set(new float[]{
+                    -1f, 0f, 0f, 0f, 255f,
+                    0f, 1f, 0f, 0f, 0f,
+                    0f, 0f, 1f, 0f, 0f,
+                    0f, 0f, 0f, 1f, 0f
+            });
+            matrix.postConcat(tmp);
+            tmp.setYUV2RGB();
+            matrix.postConcat(tmp);
+            paint.setColorFilter(new ColorMatrixColorFilter(matrix));
+            mView.setLayerType(View.LAYER_TYPE_HARDWARE, paint);
+
+            hsl[2] = 1f - hsl[2];
+            mBackgroundColor = ColorUtils.HSLToColor(hsl);
+        }
+    }
+
+    @Override
     protected boolean shouldClearBackgroundOnReapply() {
         return false;
     }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/wrapper/NotificationViewWrapper.java b/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/wrapper/NotificationViewWrapper.java
index 1efdc56874f3..9258c9971451 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/wrapper/NotificationViewWrapper.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/wrapper/NotificationViewWrapper.java
@@ -37,7 +37,7 @@ public abstract class NotificationViewWrapper implements TransformableView {
     protected final View mView;
     protected final ExpandableNotificationRow mRow;
 
-    private int mBackgroundColor = 0;
+    protected int mBackgroundColor = 0;
 
     public static NotificationViewWrapper wrap(Context ctx, View v, ExpandableNotificationRow row) {
         if (v.getId() == com.android.internal.R.id.status_bar_latest_event_content) {