Add an @hide way to adjust CursorAnchorInfo for another Matrix

This is a preparation to support CursorAnchorInfo API in ActivityView.

In order to enable the system to automatically adjust CursorAnchorInfo
object between the IME client and IME, there needs to be an @hide
method to create a new CursorAnchorInfo instance with applying an
additional coordinate transformation Matrix, which is what this CL
does.

This CL also cleans up CursorAnchorInfoTest.java as most of test there
were already moved to CTS [1].

Anyway, this is a mechanical change.  There should be no behavior
change in existing methods in CursorAnchorInfo.

 [1]: Ib758bddff34b4722b39c94e7ad4e8f8da2bb8b92
      c4ef1d6ec22dc2af2ed339fd4e78075903783be0

Bug: 115693908
Test: atest CtsInputMethodTestCases:CursorAnchorInfoTest
Test: atest FrameworksCoreTests:CursorAnchorInfoTest
Change-Id: Ic7f9057623ffc61ec7a6121735dc39adecf4649d

1 files changed, 81 insertions, 20 deletions

diff --git a/core/java/android/view/inputmethod/CursorAnchorInfo.java b/core/java/android/view/inputmethod/CursorAnchorInfo.java
index ee5b3ecc7682..21ead4c62366 100644
--- a/core/java/android/view/inputmethod/CursorAnchorInfo.java
+++ b/core/java/android/view/inputmethod/CursorAnchorInfo.java
@@ -17,6 +17,7 @@
 package android.view.inputmethod;
 
 import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.graphics.Matrix;
 import android.graphics.RectF;
 import android.os.Parcel;
@@ -388,7 +389,7 @@ public final class CursorAnchorInfo implements Parcelable {
                             "required when positional parameters are specified.");
                 }
             }
-            return new CursorAnchorInfo(this);
+            return CursorAnchorInfo.create(this);
         }
 
         /**
@@ -412,30 +413,90 @@ public final class CursorAnchorInfo implements Parcelable {
         }
     }
 
-    private CursorAnchorInfo(final Builder builder) {
-        mSelectionStart = builder.mSelectionStart;
-        mSelectionEnd = builder.mSelectionEnd;
-        mComposingTextStart = builder.mComposingTextStart;
-        mComposingText = builder.mComposingText;
-        mInsertionMarkerFlags = builder.mInsertionMarkerFlags;
-        mInsertionMarkerHorizontal = builder.mInsertionMarkerHorizontal;
-        mInsertionMarkerTop = builder.mInsertionMarkerTop;
-        mInsertionMarkerBaseline = builder.mInsertionMarkerBaseline;
-        mInsertionMarkerBottom = builder.mInsertionMarkerBottom;
-        mCharacterBoundsArray = builder.mCharacterBoundsArrayBuilder != null ?
-                builder.mCharacterBoundsArrayBuilder.build() : null;
-        mMatrixValues = new float[9];
+    private static CursorAnchorInfo create(Builder builder) {
+        final SparseRectFArray characterBoundsArray =
+                builder.mCharacterBoundsArrayBuilder != null
+                        ? builder.mCharacterBoundsArrayBuilder.build()
+                        : null;
+        final float[] matrixValues = new float[9];
         if (builder.mMatrixInitialized) {
-            System.arraycopy(builder.mMatrixValues, 0, mMatrixValues, 0, 9);
+            System.arraycopy(builder.mMatrixValues, 0, matrixValues, 0, 9);
         } else {
-            Matrix.IDENTITY_MATRIX.getValues(mMatrixValues);
+            Matrix.IDENTITY_MATRIX.getValues(matrixValues);
         }
 
+        return new CursorAnchorInfo(builder.mSelectionStart, builder.mSelectionEnd,
+                builder.mComposingTextStart, builder.mComposingText, builder.mInsertionMarkerFlags,
+                builder.mInsertionMarkerHorizontal, builder.mInsertionMarkerTop,
+                builder.mInsertionMarkerBaseline, builder.mInsertionMarkerBottom,
+                characterBoundsArray, matrixValues);
+    }
+
+    private CursorAnchorInfo(int selectionStart, int selectionEnd, int composingTextStart,
+            @Nullable CharSequence composingText, int insertionMarkerFlags,
+            float insertionMarkerHorizontal, float insertionMarkerTop,
+            float insertionMarkerBaseline, float insertionMarkerBottom,
+            @Nullable  SparseRectFArray characterBoundsArray, @NonNull float[] matrixValues) {
+        mSelectionStart = selectionStart;
+        mSelectionEnd = selectionEnd;
+        mComposingTextStart = composingTextStart;
+        mComposingText = composingText;
+        mInsertionMarkerFlags = insertionMarkerFlags;
+        mInsertionMarkerHorizontal = insertionMarkerHorizontal;
+        mInsertionMarkerTop = insertionMarkerTop;
+        mInsertionMarkerBaseline = insertionMarkerBaseline;
+        mInsertionMarkerBottom = insertionMarkerBottom;
+        mCharacterBoundsArray = characterBoundsArray;
+        mMatrixValues = matrixValues;
+
         // To keep hash function simple, we only use some complex objects for hash.
-        int hash = Objects.hashCode(mComposingText);
-        hash *= 31;
-        hash += Arrays.hashCode(mMatrixValues);
-        mHashCode = hash;
+        int hashCode = Objects.hashCode(mComposingText);
+        hashCode *= 31;
+        hashCode += Arrays.hashCode(matrixValues);
+        mHashCode = hashCode;
+    }
+
+    /**
+     * Creates a new instance of {@link CursorAnchorInfo} by applying {@code parentMatrix} to
+     * the coordinate transformation matrix.
+     *
+     * @param original {@link CursorAnchorInfo} to be cloned from.
+     * @param parentMatrix {@link Matrix} to be applied to {@code original.getMatrix()}
+     * @return A new instance of {@link CursorAnchorInfo} whose {@link CursorAnchorInfo#getMatrix()}
+     *         returns {@code parentMatrix * original.getMatrix()}.
+     * @hide
+     */
+    public static CursorAnchorInfo createForAdditionalParentMatrix(CursorAnchorInfo original,
+            @NonNull Matrix parentMatrix) {
+        return new CursorAnchorInfo(original.mSelectionStart, original.mSelectionEnd,
+                original.mComposingTextStart, original.mComposingText,
+                original.mInsertionMarkerFlags, original.mInsertionMarkerHorizontal,
+                original.mInsertionMarkerTop, original.mInsertionMarkerBaseline,
+                original.mInsertionMarkerBottom, original.mCharacterBoundsArray,
+                computeMatrixValues(parentMatrix, original));
+    }
+
+    /**
+     * Returns a float array that represents {@link Matrix} elements for
+     * {@code parentMatrix * info.getMatrix()}.
+     *
+     * @param parentMatrix {@link Matrix} to be multiplied.
+     * @param info {@link CursorAnchorInfo} to provide {@link Matrix} to be multiplied.
+     * @return {@code parentMatrix * info.getMatrix()}.
+     */
+    private static float[] computeMatrixValues(@NonNull Matrix parentMatrix,
+            @NonNull CursorAnchorInfo info) {
+        if (parentMatrix.isIdentity()) {
+            return info.mMatrixValues;
+        }
+
+        final Matrix newMatrix = new Matrix();
+        newMatrix.setValues(info.mMatrixValues);
+        newMatrix.postConcat(parentMatrix);
+
+        final float[] matrixValues = new float[9];
+        newMatrix.getValues(matrixValues);
+        return matrixValues;
     }
 
     /**