[Contextual Search] Add support for crushed sprites and animate the search provider icon

ui/android/java/src/org/chromium/ui/resources/sprites/CrushedSpriteResource.java

Index: ui/android/java/src/org/chromium/ui/resources/sprites/CrushedSpriteResource.java
diff --git a/ui/android/java/src/org/chromium/ui/resources/sprites/CrushedSpriteResource.java b/ui/android/java/src/org/chromium/ui/resources/sprites/CrushedSpriteResource.java
new file mode 100644
index 0000000000000000000000000000000000000000..43343c0ed0a199305ff4d57f11de67c0d22ad301
--- /dev/null
+++ b/ui/android/java/src/org/chromium/ui/resources/sprites/CrushedSpriteResource.java
@@ -0,0 +1,269 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.ui.resources.sprites;
+
+import android.content.res.Resources;
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.graphics.Rect;
+import android.util.JsonReader;
+
+import org.chromium.base.TraceEvent;
+import org.chromium.ui.resources.Resource;
+
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+
+/**
+ * A {@link Resource} that provides an unscaled {@link Bitmap} and corresponding metadata for a
+ * crushed sprite. A crushed sprite animation is run by drawing rectangles from a bitmap to a
+ * canvas. Each frame in the animation draws its rectangles on top of the previous frame.
+ *
+ * TODO(twellington): Add an Instrumentation test for this class.
+ */
+public class CrushedSpriteResource implements Resource {
+    private static final Rect EMPTY_RECT = new Rect();
+
+    private Bitmap mBitmap;
+    private final Rect mBitmapSize = new Rect();
+    private int mSpriteWidth;
+    private int mSpriteHeight;
+    private int[][] mRectangles;
+
+    /**
+     * @param bitmapResId The id of the bitmap resource.
+     * @param metadataResId The id of the raw resource containing JSON metadata.
+     * @param resources A {@link Resources} instance to load assets from.
+     */
+    public CrushedSpriteResource(int bitmapResId, int metadataResId, Resources resources) {
+        mBitmap = loadBitmap(bitmapResId, resources);
+
+        if (mBitmap != null) {
+            mBitmapSize.set(0, 0, mBitmap.getWidth(), mBitmap.getHeight());
+            try {
+                TraceEvent.begin("CrushedSpriteResource.parseMetadata");
+                parseMetadata(metadataResId, mBitmap.getDensity(), resources);
+                TraceEvent.end("CrushedSpriteResource.parseMetadata");
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+
+    /**
+     * Convenience method for use in reloading an unscaled {@link Bitmap} without recreating the
+     * entire resource.
+     * @param bitmapResId The id of the bitmap resource for this crushed sprite.
+     * @param resources A {@link Resources} instance to load assets from.
+     */
+    public static Bitmap loadBitmap(int bitmapResId, Resources resources) {
+        TraceEvent.begin("CrushedSpriteResource.loadBitmap");
+        BitmapFactory.Options opts = new BitmapFactory.Options();
+        opts.inScaled = false;
+        Bitmap bitmap = BitmapFactory.decodeResource(resources, bitmapResId, opts);
+        TraceEvent.end("CrushedSpriteResource.loadBitmap");
+        return bitmap;
+    }
+
+    @Override
+    public Bitmap getBitmap() {
+        return mBitmap;
+    }
+
+    @Override
+    public Rect getBitmapSize() {
+        return mBitmapSize;
+    }
+
+    @Override
+    public Rect getPadding() {
+        return EMPTY_RECT;
+    }
+
+    @Override
+    public Rect getAperture() {
+        return EMPTY_RECT;
+    }
+
+    /**
+     * @return The unscaled width of an individual sprite in px.
+     */
+    public int getSpriteWidth() {
+        return mSpriteWidth;
+    }
+
+    /**
+     * @return The unscaled height of an individual sprite in px.
+     */
+    public int getSpriteHeight() {
+        return mSpriteHeight;
+    }
+
+    /**
+     * @return The number of frames in the sprite animation.
+     */
+    public int getFrameCount() {
+        return mRectangles.length;
+    }
+
+    /**
+     * Each sprite frame is represented by a set of rectangles. Most frames consist of small
+     * rectangles representing the change from the previous frame. Each rectangle is represented
+     * using six consecutive values that specify the values to be used when creating the destination
+     * and source rectangles that get painted:
+     * 0: destination x   1: destination y   2: source x   3: source y   4: width   5: height
+     *
+     * @return The unscaled rectangles that need to be painted for each sprite frame in px.
+     */
+    public int[][] getFrameRectangles() {
+        return mRectangles.clone();
+    }
+
+    /**
+     * Parses the raw JSON resource specified by {@code metadataResId}. The JSON is expected to be
+     * in this format:
+     * {
+     *   "apiVersion": <version number>,
+     *   "densities":
+     *   [
+     *     {
+     *       "density": <density number>,
+     *       "width": <unscaled sprite width>,
+     *       "height": <unscaled sprite height>,
+     *       "rectangles": [
+     *         [<list of ints for frame 0>],
+     *         [<list of ints for frame 1>],
+     *          ......
+     *       ]
+     *     },
+     *     {
+     *       "density": <density number>,
+     *       "width": <unscaled sprite width>,
+     *       "height": <unscaled sprite height>,
+     *       "rectangles": [
+     *         [<list of ints for frame 0>],
+     *         [<list of ints for frame 1>],
+     *         ......
+     *       ]
+     *     },
+     *     ......
+     *   ]
+     * }
+     *
+     * @param metadataResId The id of the raw resource containing JSON to parse.
+     * @param bitmapDensity The density of the unscaled {@link Bitmap} that was loaded.
+     * @param resources A {@link Resources} instance to load assets from.
+     * @throws IOException
+     */
+    private void parseMetadata(int metadataResId, int bitmapDensity, Resources resources)
+            throws IOException {
+        InputStream inputStream = resources.openRawResource(metadataResId);
+        JsonReader reader = new JsonReader(new InputStreamReader(inputStream));
+        try {
+            reader.beginObject(); // Start reading top-level object.
+
+            // Consume apiVersion.
+            String name = reader.nextName();
+            assert name.equals("apiVersion");
+            reader.nextString();
+
+            // Parse array of densities.
+            name = reader.nextName();
+            assert name.equals("densities");
+            reader.beginArray(); // Start reading array of densities.
+            while (reader.hasNext()) {
+                reader.beginObject(); // Start reading object for this density.
+                boolean foundDensity = parseMetadataForDensity(reader, bitmapDensity);
+                reader.endObject(); // Stop reading object for this density.
+
+                if (foundDensity) break;
+            }
+        } finally {
+            reader.close();
+            inputStream.close();
+        }
+    }
+
+    /**
+     * Reads a JSON object for a specific density and populates variables if the density matches
+     * {@code bitmapDensity}.
+     *
+     * @param reader The JsonReader reading the JSON metadata.
+     * @param bitmapDensity The density of the unscaled {@link Bitmap} that was loaded.
+     * @return True if the JSON object being parsed corresponds to bitmapDensity.
+     * @throws IOException
+     */
+    private boolean parseMetadataForDensity(JsonReader reader, int bitmapDensity)
+            throws IOException {
+        String name = reader.nextName();
+        assert name.equals("density");
+        int density = reader.nextInt();
+
+        // If this is metadata for a density other than bitmapDensity, skip parsing the rest of the
+        // object.
+        if (density != bitmapDensity) {
+            reader.skipValue(); // Skip width name.
+            reader.skipValue(); // Skip width value.
+            reader.skipValue(); // Skip height name.
+            reader.skipValue(); // Skip height value.
+            reader.skipValue(); // Skip rectangles name.
+            reader.skipValue(); // Skip rectangles array.
+            return false;
+        }
+
+        name = reader.nextName();
+        assert name.equals("width");
+        mSpriteWidth = reader.nextInt();
+
+        name = reader.nextName();
+        assert name.equals("height");
+        mSpriteHeight = reader.nextInt();
+
+        name = reader.nextName();
+        assert name.equals("rectangles");
+
+        parseFrameRectangles(reader);
+
+        return true;
+    }
+
+
+    /**
+     * Parses the 2D JSONArray of frame rectangles and populates {@code mRectangles}.
+     * @param reader The JsonReader reading the JSON metadata.
+     * @throws IOException
+     */
+    private void parseFrameRectangles(JsonReader reader) throws IOException {
+        ArrayList<ArrayList<Integer>> allFrameRectangles = new ArrayList<ArrayList<Integer>>();
+        int frameCount = 0;
+
+        reader.beginArray(); // Start reading 2D rectangles array.
+        while (reader.hasNext()) {
+            ArrayList<Integer> frameRectangles = new ArrayList<Integer>();
+            reader.beginArray(); // Start reading frame array.
+            while (reader.hasNext()) {
+                frameRectangles.add(reader.nextInt());
+            }
+            reader.endArray(); // Stop reading frame array.
+            allFrameRectangles.add(frameRectangles);
+            frameCount++;
+        }
+        reader.endArray(); // Stop reading 2D rectangles array.
+
+        // Convert 2D ArrayList to int[][].
+        mRectangles = new int[frameCount][];
+        for (int i = 0; i < frameCount; i++) {
+            ArrayList<Integer> frameRectangles = allFrameRectangles.get(i);
+            int[] frameRectanglesArray = new int[frameRectangles.size()];
+            for (int j = 0; j < frameRectangles.size(); j++) {
+                frameRectanglesArray[j] = frameRectangles.get(j);
+            }
+            mRectangles[i] = frameRectanglesArray;
+        }
+    }
+}