diff options
Diffstat (limited to 'mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ImageResource.java')
| -rw-r--r-- | mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ImageResource.java | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ImageResource.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ImageResource.java new file mode 100644 index 0000000000..d57147f363 --- /dev/null +++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ImageResource.java @@ -0,0 +1,334 @@ +/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*- + * vim: ts=4 sw=4 expandtab: + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +package org.mozilla.gecko.util; + +import android.graphics.Bitmap; +import android.util.Log; +import androidx.annotation.AnyThread; +import androidx.annotation.NonNull; +import androidx.annotation.Nullable; +import java.util.ArrayList; +import java.util.Collections; +import java.util.List; +import java.util.Locale; +import org.mozilla.geckoview.GeckoResult; + +/** + * Represents an Web API image resource as used in web app manifests and media session metadata. + * + * @see <a href="https://www.w3.org/TR/image-resource">Image Resource</a> + */ +@AnyThread +public class ImageResource { + private static final String LOGTAG = "ImageResource"; + private static final boolean DEBUG = false; + + /** Represents the size of an image resource option. */ + public static class Size { + /** The width in pixels. */ + public final int width; + + /** The height in pixels. */ + public final int height; + + /** + * Size contructor. + * + * @param width The width in pixels. + * @param height The height in pixels. + */ + public Size(final int width, final int height) { + this.width = width; + this.height = height; + } + } + + /** The URI of the image resource. */ + public final @NonNull String src; + + /** The MIME type of the image resource. */ + public final @Nullable String type; + + /** A {@link Size} array of supported images sizes. */ + public final @Nullable Size[] sizes; + + /** + * ImageResource constructor. + * + * @param src The URI string of the image resource. + * @param type The MIME type of the image resource. + * @param sizes The supported images {@link Size} array. + */ + public ImageResource( + final @NonNull String src, final @Nullable String type, final @Nullable Size[] sizes) { + this.src = src.toLowerCase(Locale.ROOT); + this.type = type != null ? type.toLowerCase(Locale.ROOT) : null; + this.sizes = sizes; + } + + /** + * ImageResource constructor. + * + * @param src The URI string of the image resource. + * @param type The MIME type of the image resource. + * @param sizes The supported images sizes string. + * @see <a href="https://html.spec.whatwg.org/multipage/semantics.html#dom-link-sizes">Attribute + * spec for sizes</a> + */ + public ImageResource( + final @NonNull String src, final @Nullable String type, final @Nullable String sizes) { + this(src, type, parseSizes(sizes)); + } + + private static @Nullable Size[] parseSizes(final @Nullable String sizesStr) { + if (sizesStr == null || sizesStr.isEmpty()) { + return null; + } + + final String[] sizesStrs = sizesStr.toLowerCase(Locale.ROOT).split(" "); + final List<Size> sizes = new ArrayList<Size>(); + + for (final String sizeStr : sizesStrs) { + if (sizesStr.equals("any")) { + // 0-width size will always be favored. + sizes.add(new Size(0, 0)); + continue; + } + final String[] widthHeight = sizeStr.split("x"); + if (widthHeight.length != 2) { + // Not spec-compliant size. + continue; + } + try { + sizes.add(new Size(Integer.valueOf(widthHeight[0]), Integer.valueOf(widthHeight[1]))); + } catch (final NumberFormatException e) { + Log.e(LOGTAG, "Invalid image resource size", e); + } + } + if (sizes.isEmpty()) { + return null; + } + return sizes.toArray(new Size[0]); + } + + public static @NonNull ImageResource fromBundle(final GeckoBundle bundle) { + return new ImageResource( + bundle.getString("src"), bundle.getString("type"), bundle.getString("sizes")); + } + + @Override + public String toString() { + final StringBuilder builder = new StringBuilder("ImageResource {"); + builder + .append("src=") + .append(src) + .append("type=") + .append(type) + .append("sizes=") + .append(sizes) + .append("}"); + return builder.toString(); + } + + /** + * Get the best version of this image for size <code>size</code>. Embedders are encouraged to + * cache the result of this method keyed with this instance. + * + * @param size pixel size at which this image will be displayed at. + * @return A {@link GeckoResult} that resolves to the bitmap when ready. + */ + @NonNull + public GeckoResult<Bitmap> getBitmap(final int size) { + return ImageDecoder.instance().decode(src, size); + } + + /** + * Represents a collection of {@link ImageResource} options. Image resources are often used in a + * collection to provide multiple image options for various sizes. This data structure can be used + * to retrieve the best image resource for any given target image size. + */ + public static class Collection { + private static class SizeIndexPair { + public final int width; + public final int idx; + + public SizeIndexPair(final int width, final int idx) { + this.width = width; + this.idx = idx; + } + } + + // The individual image resources, usually each with a unique src. + private final List<ImageResource> mImages; + + // A sorted size-index list. The list is sorted based on the supported + // sizes of the images in ascending order. + private final List<SizeIndexPair> mSizeIndex; + + /* package */ Collection() { + mImages = new ArrayList<>(); + mSizeIndex = new ArrayList<>(); + } + + /** Builder class for the construction of a {@link Collection}. */ + public static class Builder { + final Collection mCollection; + + public Builder() { + mCollection = new Collection(); + } + + /** + * Add an image resource to the collection. + * + * @param image The {@link ImageResource} to be added. + * @return This builder instance. + */ + public @NonNull Builder add(final ImageResource image) { + final int index = mCollection.mImages.size(); + + if (image.sizes == null) { + // Null-sizes are handled the same as `any`. + mCollection.mSizeIndex.add(new SizeIndexPair(0, index)); + } else { + for (final Size size : image.sizes) { + mCollection.mSizeIndex.add(new SizeIndexPair(size.width, index)); + } + } + mCollection.mImages.add(image); + return this; + } + + /** + * Finalize the collection. + * + * @return The final collection. + */ + public @NonNull Collection build() { + Collections.sort(mCollection.mSizeIndex, (a, b) -> Integer.compare(a.width, b.width)); + return mCollection; + } + } + + @Override + public String toString() { + final StringBuilder builder = new StringBuilder("ImageResource.Collection {"); + builder.append("images=["); + + for (final ImageResource image : mImages) { + builder.append(image).append(", "); + } + builder.append("]}"); + return builder.toString(); + } + + /** + * Returns the best suited {@link ImageResource} for the given size. This is usually determined + * based on the minimal difference between the given size and one of the supported widths of an + * image resource. + * + * @param size The target size for the image in pixels. + * @return The best {@link ImageResource} for the given size from this collection. + */ + public @Nullable ImageResource getBest(final int size) { + if (mSizeIndex.isEmpty()) { + return null; + } + int bestMatchIdx = mSizeIndex.get(0).idx; + int lastDiff = size; + for (final SizeIndexPair sizeIndex : mSizeIndex) { + final int diff = Math.abs(sizeIndex.width - size); + if (lastDiff <= diff) { + // With increasing widths, the difference can only grow now. + // 0-width means "any", so we're finished at the first + // entry. + break; + } + lastDiff = diff; + bestMatchIdx = sizeIndex.idx; + } + return mImages.get(bestMatchIdx); + } + + /** + * Get the best version of this image for size <code>size</code>. Embedders are encouraged to + * cache the result of this method keyed with this instance. + * + * @param size pixel size at which this image will be displayed at. + * @return A {@link GeckoResult} that resolves to the bitmap when ready. + */ + @NonNull + public GeckoResult<Bitmap> getBitmap(final int size) { + final ImageResource image = getBest(size); + if (image == null) { + return GeckoResult.fromValue(null); + } + return image.getBitmap(size); + } + + public static Collection fromSizeSrcBundle(final GeckoBundle bundle) { + final Builder builder = new Builder(); + + for (final String key : bundle.keys()) { + final Integer intKey = Integer.valueOf(key); + if (intKey == null) { + Log.e(LOGTAG, "Non-integer image key: " + intKey); + + if (DEBUG) { + throw new RuntimeException("Non-integer image key: " + key); + } + continue; + } + + final String src = getImageValue(bundle.get(key)); + if (src != null) { + // Given the bundle structure, we don't have insight on + // individual image resources so we have to create an + // instance for each size entry. + final ImageResource image = + new ImageResource(src, null, new Size[] {new Size(intKey, intKey)}); + builder.add(image); + } + } + return builder.build(); + } + + private static String getImageValue(final Object value) { + // The image value can either be an object containing images for + // each theme... + if (value instanceof GeckoBundle) { + // We don't support theme_images yet, so let's just return the + // default value. + final GeckoBundle themeImages = (GeckoBundle) value; + final Object defaultImages = themeImages.get("default"); + + if (!(defaultImages instanceof String)) { + if (DEBUG) { + throw new RuntimeException("Unexpected themed_icon value."); + } + Log.e(LOGTAG, "Unexpected themed_icon value."); + return null; + } + + return (String) defaultImages; + } + + // ... or just a URL. + if (value instanceof String) { + return (String) value; + } + + // We never expect it to be something else, so let's error out here. + if (DEBUG) { + throw new RuntimeException("Unexpected image value: " + value); + } + + Log.e(LOGTAG, "Unexpected image value."); + return null; + } + } +} |