Add comprehensive KDoc documentation to FilterHelper

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/BackgroundStyleApplicator.kt

@@ -45,12 +45,22 @@ import com.facebook.react.uimanager.style.LogicalEdge
 import com.facebook.react.uimanager.style.OutlineStyle
 
 /**
- * BackgroundStyleApplicator is responsible for applying backgrounds, borders, and related effects,
- * to an Android view
+ * Utility object responsible for applying backgrounds, borders, and related visual effects to
+ * Android views.
+ *
+ * This object provides methods to manage background colors, images, borders, outlines, and box
+ * shadows for React Native views. It handles the complex layering and composition of these visual
+ * properties by managing [CompositeBackgroundDrawable] instances.
  */
 @OptIn(UnstableReactNativeAPI::class)
 public object BackgroundStyleApplicator {
 
+  /**
+   * Sets the background color of the view.
+   *
+   * @param view The view to apply the background color to
+   * @param color The color to set, or null to remove the background color
+   */
   @JvmStatic
   public fun setBackgroundColor(view: View, @ColorInt color: Int?): Unit {
     // No color to set, and no color already set
@@ -64,6 +74,12 @@ public object BackgroundStyleApplicator {
     ensureBackgroundDrawable(view).backgroundColor = color ?: Color.TRANSPARENT
   }
 
+  /**
+   * Sets the background image layers for the view.
+   *
+   * @param view The view to apply the background images to
+   * @param backgroundImageLayers The list of background image layers to apply, or null to remove
+   */
   @JvmStatic
   public fun setBackgroundImage(
       view: View,
@@ -90,12 +106,25 @@ public object BackgroundStyleApplicator {
     ensureBackgroundImageDrawable(view).backgroundRepeat = backgroundRepeats
   }
 
+  /**
+   * Gets the background color of the view.
+   *
+   * @param view The view to get the background color from
+   * @return The background color, or null if no background color is set
+   */
   @JvmStatic
   @ColorInt
   public fun getBackgroundColor(view: View): Int? {
     return getBackground(view)?.backgroundColor
   }
 
+  /**
+   * Sets the border width for a specific edge of the view.
+   *
+   * @param view The view to apply the border width to
+   * @param edge The logical edge (start, end, top, bottom, etc.) to set the width for
+   * @param width The border width in DIPs, or null to remove
+   */
   @JvmStatic
   public fun setBorderWidth(view: View, edge: LogicalEdge, width: Float?): Unit {
     val composite = ensureCompositeBackgroundDrawable(view)
@@ -121,6 +150,13 @@ public object BackgroundStyleApplicator {
     }
   }
 
+  /**
+   * Gets the border width for a specific edge of the view.
+   *
+   * @param view The view to get the border width from
+   * @param edge The logical edge to get the width for
+   * @return The border width in DIPs, or null if not set
+   */
   @JvmStatic
   public fun getBorderWidth(view: View, edge: LogicalEdge): Float? {
     val width = getBorder(view)?.borderWidth?.getRaw(edge.toSpacingType())
@@ -131,17 +167,38 @@ public object BackgroundStyleApplicator {
     }
   }
 
+  /**
+   * Sets the border color for a specific edge of the view.
+   *
+   * @param view The view to apply the border color to
+   * @param edge The logical edge to set the color for
+   * @param color The border color, or null to remove
+   */
   @JvmStatic
   public fun setBorderColor(view: View, edge: LogicalEdge, @ColorInt color: Int?): Unit {
     ensureBorderDrawable(view).setBorderColor(edge, color)
   }
 
+  /**
+   * Gets the border color for a specific edge of the view.
+   *
+   * @param view The view to get the border color from
+   * @param edge The logical edge to get the color for
+   * @return The border color, or null if not set
+   */
   @JvmStatic
   @ColorInt
   public fun getBorderColor(view: View, edge: LogicalEdge): Int? {
     return getBorder(view)?.getBorderColor(edge)
   }
 
+  /**
+   * Sets the border radius for a specific corner of the view.
+   *
+   * @param view The view to apply the border radius to
+   * @param corner The corner property to set the radius for
+   * @param radius The border radius value (length or percentage), or null to remove
+   */
   @JvmStatic
   public fun setBorderRadius(
       view: View,
@@ -183,22 +240,47 @@ public object BackgroundStyleApplicator {
     compositeBackgroundDrawable.invalidateSelf()
   }
 
+  /**
+   * Gets the border radius for a specific corner of the view.
+   *
+   * @param view The view to get the border radius from
+   * @param corner The corner property to get the radius for
+   * @return The border radius value, or null if not set
+   */
   @JvmStatic
   public fun getBorderRadius(view: View, corner: BorderRadiusProp): LengthPercentage? {
 
     return getCompositeBackgroundDrawable(view)?.borderRadius?.get(corner)
   }
 
+  /**
+   * Sets the border style for the view.
+   *
+   * @param view The view to apply the border style to
+   * @param borderStyle The border style (solid, dashed, dotted), or null to remove
+   */
   @JvmStatic
   public fun setBorderStyle(view: View, borderStyle: BorderStyle?) {
     ensureBorderDrawable(view).borderStyle = borderStyle
   }
 
+  /**
+   * Gets the border style of the view.
+   *
+   * @param view The view to get the border style from
+   * @return The border style, or null if not set
+   */
   @JvmStatic
   public fun getBorderStyle(view: View): BorderStyle? {
     return getBorder(view)?.borderStyle
   }
 
+  /**
+   * Sets the outline color for the view (Fabric only).
+   *
+   * @param view The view to apply the outline color to
+   * @param outlineColor The outline color, or null to remove
+   */
   @JvmStatic
   public fun setOutlineColor(view: View, @ColorInt outlineColor: Int?) {
     if (ViewUtil.getUIManagerType(view) != UIManagerType.FABRIC) {
@@ -211,8 +293,20 @@ public object BackgroundStyleApplicator {
     }
   }
 
+  /**
+   * Gets the outline color of the view.
+   *
+   * @param view The view to get the outline color from
+   * @return The outline color, or null if not set
+   */
   @JvmStatic public fun getOutlineColor(view: View): Int? = getOutlineDrawable(view)?.outlineColor
 
+  /**
+   * Sets the outline offset for the view (Fabric only).
+   *
+   * @param view The view to apply the outline offset to
+   * @param outlineOffset The outline offset in DIPs
+   */
   @JvmStatic
   public fun setOutlineOffset(view: View, outlineOffset: Float): Unit {
     if (ViewUtil.getUIManagerType(view) != UIManagerType.FABRIC) {
@@ -223,8 +317,20 @@ public object BackgroundStyleApplicator {
     outline.outlineOffset = outlineOffset.dpToPx()
   }
 
+  /**
+   * Gets the outline offset of the view.
+   *
+   * @param view The view to get the outline offset from
+   * @return The outline offset in pixels, or null if not set
+   */
   public fun getOutlineOffset(view: View): Float? = getOutlineDrawable(view)?.outlineOffset
 
+  /**
+   * Sets the outline style for the view (Fabric only).
+   *
+   * @param view The view to apply the outline style to
+   * @param outlineStyle The outline style (solid, dashed, dotted), or null to remove
+   */
   @JvmStatic
   public fun setOutlineStyle(view: View, outlineStyle: OutlineStyle?): Unit {
     if (ViewUtil.getUIManagerType(view) != UIManagerType.FABRIC) {
@@ -237,8 +343,20 @@ public object BackgroundStyleApplicator {
     }
   }
 
+  /**
+   * Gets the outline style of the view.
+   *
+   * @param view The view to get the outline style from
+   * @return The outline style, or null if not set
+   */
   public fun getOutlineStyle(view: View): OutlineStyle? = getOutlineDrawable(view)?.outlineStyle
 
+  /**
+   * Sets the outline width for the view (Fabric only).
+   *
+   * @param view The view to apply the outline width to
+   * @param width The outline width in DIPs
+   */
   @JvmStatic
   public fun setOutlineWidth(view: View, width: Float) {
     if (ViewUtil.getUIManagerType(view) != UIManagerType.FABRIC) {
@@ -249,8 +367,20 @@ public object BackgroundStyleApplicator {
     outline.outlineWidth = width.dpToPx()
   }
 
+  /**
+   * Gets the outline width of the view.
+   *
+   * @param view The view to get the outline width from
+   * @return The outline width in pixels, or null if not set
+   */
   public fun getOutlineWidth(view: View): Float? = getOutlineDrawable(view)?.outlineOffset
 
+  /**
+   * Sets box shadows for the view (Fabric only).
+   *
+   * @param view The view to apply box shadows to
+   * @param shadows The list of box shadow styles to apply
+   */
   @JvmStatic
   public fun setBoxShadow(view: View, shadows: List<BoxShadow>) {
     if (ViewUtil.getUIManagerType(view) != UIManagerType.FABRIC) {
@@ -309,6 +439,12 @@ public object BackgroundStyleApplicator {
             .withNewShadows(outerShadows = outerShadows, innerShadows = innerShadows)
   }
 
+  /**
+   * Sets box shadows for the view from a ReadableArray (Fabric only).
+   *
+   * @param view The view to apply box shadows to
+   * @param shadows The array of box shadow definitions, or null to remove all shadows
+   */
   @JvmStatic
   public fun setBoxShadow(view: View, shadows: ReadableArray?) {
     if (shadows == null) {
@@ -323,11 +459,26 @@ public object BackgroundStyleApplicator {
     BackgroundStyleApplicator.setBoxShadow(view, shadowStyles)
   }
 
+  /**
+   * Sets a feedback underlay drawable for the view.
+   *
+   * @param view The view to apply the feedback underlay to
+   * @param drawable The drawable to use as feedback underlay, or null to remove
+   */
   @JvmStatic
   public fun setFeedbackUnderlay(view: View, drawable: Drawable?) {
     ensureCompositeBackgroundDrawable(view).withNewFeedbackUnderlay(drawable)
   }
 
+  /**
+   * Clips the canvas to the padding box of the view.
+   *
+   * The padding box is the area within the borders of the view, accounting for border radius if
+   * present.
+   *
+   * @param view The view whose padding box defines the clipping region
+   * @param canvas The canvas to clip
+   */
   @JvmStatic
   public fun clipToPaddingBox(view: View, canvas: Canvas) {
     val drawingRect = Rect()
@@ -366,6 +517,13 @@ public object BackgroundStyleApplicator {
     }
   }
 
+  /**
+   * Resets the background styling of the view to its original state.
+   *
+   * This removes any CompositeBackgroundDrawable and restores the original background.
+   *
+   * @param view The view to reset
+   */
   @JvmStatic
   public fun reset(view: View) {
     if (view.background is CompositeBackgroundDrawable) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/BlendModeHelper.kt

@@ -14,10 +14,23 @@ import android.view.ViewGroup
 import androidx.core.view.children
 import com.facebook.react.R
 
+/**
+ * Helper object for parsing and handling CSS mix-blend-mode properties on Android Q+ (API 29+).
+ *
+ * This object provides utilities to convert CSS mix-blend-mode string values into Android's
+ * [BlendMode] enumeration and to determine when views need isolated layers for proper blending.
+ */
 @TargetApi(29)
 internal object BlendModeHelper {
 
-  /** @see <a href="https://www.w3.org/TR/compositing-1/#mix-blend-mode">mix-blend-mode</a> */
+  /**
+   * Parses a CSS mix-blend-mode string value into an Android BlendMode.
+   *
+   * @param mixBlendMode The CSS mix-blend-mode value (e.g., "multiply", "screen", "overlay")
+   * @return The corresponding [BlendMode], or null if "normal" or on unsupported Android versions
+   * @throws IllegalArgumentException if the mix-blend-mode name is invalid
+   * @see <a href="https://www.w3.org/TR/compositing-1/#mix-blend-mode">mix-blend-mode</a>
+   */
   @JvmStatic
   fun parseMixBlendMode(mixBlendMode: String?): BlendMode? {
     if (mixBlendMode == null || Build.VERSION.SDK_INT < Build.VERSION_CODES.Q) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/ComponentNameResolver.kt

@@ -9,8 +9,18 @@ package com.facebook.react.uimanager
 
 import com.facebook.proguard.annotations.DoNotStripAny
 
+/**
+ * Interface for resolving component names registered in React Native.
+ *
+ * This interface provides access to all registered component names in the React Native runtime,
+ * which is useful for debugging and inspection purposes.
+ */
 @DoNotStripAny
 internal interface ComponentNameResolver {
-  /* returns a list of all the component names that are registered in React Native. */
+  /**
+   * Gets the list of all component names registered in React Native.
+   *
+   * @return An array of all registered component names
+   */
   val componentNames: Array<String>
 }

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/ComponentNameResolverBinding.kt

@@ -12,11 +12,23 @@ import com.facebook.react.bridge.RuntimeExecutor
 import com.facebook.soloader.SoLoader
 import kotlin.jvm.JvmStatic
 
+/**
+ * JNI binding for installing a ComponentNameResolver into the JavaScript runtime.
+ *
+ * This object provides a native binding to install a [ComponentNameResolver] into the React Native
+ * JavaScript runtime, making component name information available to the native side.
+ */
 @DoNotStripAny
 internal object ComponentNameResolverBinding {
   init {
     SoLoader.loadLibrary("uimanagerjni")
   }
 
+  /**
+   * Installs a ComponentNameResolver into the JavaScript runtime.
+   *
+   * @param runtimeExecutor The runtime executor for the JavaScript runtime
+   * @param componentNameResolver The component name resolver to install
+   */
   @JvmStatic external fun install(runtimeExecutor: RuntimeExecutor, componentNameResolver: Any)
 }

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/FilterHelper.kt

@@ -21,9 +21,25 @@ import com.facebook.react.uimanager.PixelUtil.dpToPx
 import kotlin.math.cos
 import kotlin.math.sin
 
+/**
+ * Helper object for parsing and applying CSS filter effects on Android S+ (API 31+).
+ *
+ * This object provides utilities to convert CSS filter arrays into Android [RenderEffect] chains
+ * and [ColorMatrixColorFilter] objects. Supports filters like blur, brightness, contrast,
+ * grayscale, sepia, saturate, hue-rotate, invert, opacity, and drop-shadow.
+ *
+ * @see <a href="https://www.w3.org/TR/filter-effects-1/">CSS Filter Effects Module Level 1</a>
+ */
 @TargetApi(31)
 internal object FilterHelper {
 
+  /**
+   * Parses a ReadableArray of CSS filter definitions into a chained [RenderEffect].
+   *
+   * @param filters The array of filter definitions, or null
+   * @return A chained RenderEffect representing all filters, or null if no filters provided
+   * @throws IllegalArgumentException if an invalid filter name is encountered
+   */
   @JvmStatic
   fun parseFilters(filters: ReadableArray?): RenderEffect? {
     filters ?: return null