[EoC] Use ContextualSuggestionsBridge in Java-layer

Start talking to the new, component-specific bridge rather than the
SnippetsBridge.

Also, make ContextualSuggestionsBridge and ContextualSuggestionsCluster
package protected to enforce ContextualSuggestionsCoordinator being
the only Java class visible outside of the package.

BUG=822945,827654

Change-Id: Ib599a1ec9f6af53046c71c8b762b64398cb306cc
Reviewed-on: https://chromium-review.googlesource.com/996404
Commit-Queue: Theresa <twellington@chromium.org>
Reviewed-by: Filip Gorski <fgorski@chromium.org>
Cr-Commit-Position: refs/heads/master@{#548242}

chrome/android/java/src/org/chromium/chrome/browser/contextual_suggestions/ContextualSuggestionsBridge.java

@@ -21,7 +21,7 @@ import java.util.List;
  * Provides access to contextual suggestions.
  */
 @JNINamespace("contextual_suggestions")
-public class ContextualSuggestionsBridge {
+class ContextualSuggestionsBridge {
     private long mNativeContextualSuggestionsBridge;
 
     /** Result of fetching contextual suggestions. */
@@ -49,12 +49,12 @@ public class ContextualSuggestionsBridge {
      *
      * @param profile Profile of the user that we will retrieve snippets for.
      */
-    public ContextualSuggestionsBridge(Profile profile) {
+    ContextualSuggestionsBridge(Profile profile) {
         mNativeContextualSuggestionsBridge = nativeInit(profile);
     }
 
-    /** Destroys the brige. */
-    public void destroy() {
+    /** Destroys the bridge. */
+    void destroy() {
         assert mNativeContextualSuggestionsBridge != 0;
         nativeDestroy(mNativeContextualSuggestionsBridge);
         mNativeContextualSuggestionsBridge = 0;
@@ -65,27 +65,27 @@ public class ContextualSuggestionsBridge {
      * @param url URL for which to fetch suggestions.
      * @param callback Callback used to return suggestions for a given URL.
      */
-    public void fetchSuggestions(String url, Callback<ContextualSuggestionsResult> callback) {
+    void fetchSuggestions(String url, Callback<ContextualSuggestionsResult> callback) {
         assert mNativeContextualSuggestionsBridge != 0;
         nativeFetchSuggestions(mNativeContextualSuggestionsBridge, url, callback);
     }
 
     /** Fetches a thumbnail for the suggestion. */
-    public void fetchSuggestionImage(SnippetArticle suggestion, Callback<Bitmap> callback) {
+    void fetchSuggestionImage(SnippetArticle suggestion, Callback<Bitmap> callback) {
         assert mNativeContextualSuggestionsBridge != 0;
         nativeFetchSuggestionImage(
                 mNativeContextualSuggestionsBridge, suggestion.mIdWithinCategory, callback);
     }
 
     /** Fetches a favicon for the suggestion. */
-    public void fetchSuggestionFavicon(SnippetArticle suggestion, Callback<Bitmap> callback) {
+    void fetchSuggestionFavicon(SnippetArticle suggestion, Callback<Bitmap> callback) {
         assert mNativeContextualSuggestionsBridge != 0;
         nativeFetchSuggestionFavicon(
                 mNativeContextualSuggestionsBridge, suggestion.mIdWithinCategory, callback);
     }
 
     /** Requests the backend to clear state related to this bridge. */
-    public void clearState() {
+    void clearState() {
         assert mNativeContextualSuggestionsBridge != 0;
         nativeClearState(mNativeContextualSuggestionsBridge);
     }
@@ -96,7 +96,7 @@ public class ContextualSuggestionsBridge {
      * @param webContents Web contents with the document for which event is reported.
      * @param eventId Id of the reported event.
      */
-    public void reportEvent(WebContents webContents, int eventId) {
+    void reportEvent(WebContents webContents, int eventId) {
         assert mNativeContextualSuggestionsBridge != 0;
         assert webContents != null && !webContents.isDestroyed();
 
@@ -114,10 +114,11 @@ public class ContextualSuggestionsBridge {
     }
 
     @CalledByNative
-    private static void addSuggestionToLastCluster(List<ContextualSuggestionsCluster> clusters,
-            String id, String title, String publisher, String url) {
-        assert clusters.size() > 0;
-        clusters.get(clusters.size() - 1)
+    private static void addSuggestionToLastCluster(ContextualSuggestionsResult result, String id,
+            String title, String publisher, String url) {
+        assert result.getClusters().size() > 0;
+        result.getClusters()
+                .get(result.getClusters().size() - 1)
                 .getSuggestions()
                 .add(new SnippetArticle(KnownCategories.CONTEXTUAL, id, title, publisher, url,
                         /*publishTimestamp=*/0, /*score=*/0f, /*fetchTimestamp=*/0,

chrome/android/java/src/org/chromium/chrome/browser/contextual_suggestions/ContextualSuggestionsCluster.java

@@ -4,6 +4,8 @@
 
 package org.chromium.chrome.browser.contextual_suggestions;
 
+import android.text.TextUtils;
+
 import org.chromium.base.Callback;
 import org.chromium.chrome.browser.ntp.cards.ChildNode;
 import org.chromium.chrome.browser.ntp.cards.InnerNode;
@@ -22,38 +24,34 @@ import java.util.List;
 import java.util.Set;
 
 /** A node in a tree that groups contextual suggestions in a cluster of related items. */
-public class ContextualSuggestionsCluster extends InnerNode {
+class ContextualSuggestionsCluster extends InnerNode {
     private final String mTitle;
+    private final boolean mShouldShowTitle;
     private final List<SnippetArticle> mSuggestions = new ArrayList<>();
 
     private SectionHeader mHeader;
-    private boolean mShouldShowTitle = true;
 
     /** Creates a new contextual suggestions cluster with provided title. */
-    public ContextualSuggestionsCluster(String title) {
+    ContextualSuggestionsCluster(String title) {
         mTitle = title;
+        mShouldShowTitle = !TextUtils.isEmpty(title);
     }
 
     /** @return A title related to this cluster */
-    public String getTitle() {
+    String getTitle() {
         return mTitle;
     }
 
     /** @return A list of suggestions in this cluster */
-    public List<SnippetArticle> getSuggestions() {
+    List<SnippetArticle> getSuggestions() {
         return mSuggestions;
     }
 
-    /** @param showTitle Whether the cluster title should be shown. */
-    public void setShouldShowTitle(boolean showTitle) {
-        mShouldShowTitle = showTitle;
-    }
-
     /**
      * Called to build the tree node's children. Should be called after all suggestions have been
      * added.
      */
-    public void buildChildren() {
+    void buildChildren() {
         if (mShouldShowTitle) {
             mHeader = new SectionHeader(mTitle);
             addChild(mHeader);

chrome/android/java/src/org/chromium/chrome/browser/contextual_suggestions/ContextualSuggestionsMediator.java

@@ -9,11 +9,9 @@ import android.support.annotation.Nullable;
 import android.text.TextUtils;
 
 import org.chromium.base.ContextUtils;
-import org.chromium.chrome.R;
 import org.chromium.chrome.browser.fullscreen.ChromeFullscreenManager;
 import org.chromium.chrome.browser.fullscreen.ChromeFullscreenManager.FullscreenListener;
 import org.chromium.chrome.browser.ntp.snippets.SnippetArticle;
-import org.chromium.chrome.browser.ntp.snippets.SnippetsBridge;
 import org.chromium.chrome.browser.profiles.Profile;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.util.MathUtils;
@@ -40,7 +38,7 @@ class ContextualSuggestionsMediator implements EnabledStateMonitor.Observer, Fet
     private final EnabledStateMonitor mEnabledStateMonitor;
     private final ChromeFullscreenManager mFullscreenManager;
 
-    private @Nullable SnippetsBridge mBridge;
+    private @Nullable ContextualSuggestionsSource mSuggestionsSource;
     private @Nullable FetchHelper mFetchHelper;
     private @Nullable String mCurrentRequestUrl;
     private @Nullable BottomSheetObserver mSheetObserver;
@@ -82,7 +80,7 @@ class ContextualSuggestionsMediator implements EnabledStateMonitor.Observer, Fet
                 // remain hidden since their offset from the bottom of the screen is determined by
                 // the top controls.
                 if (!mDidSuggestionsShowForTab && mModel.hasSuggestions()
-                        && areBrowserControlsHidden() && mBridge != null) {
+                        && areBrowserControlsHidden() && mSuggestionsSource != null) {
                     showContentInSheet();
                 }
             }
@@ -104,9 +102,9 @@ class ContextualSuggestionsMediator implements EnabledStateMonitor.Observer, Fet
             mFetchHelper = null;
         }
 
-        if (mBridge != null) {
-            mBridge.destroy();
-            mBridge = null;
+        if (mSuggestionsSource != null) {
+            mSuggestionsSource.destroy();
+            mSuggestionsSource = null;
         }
     }
 
@@ -121,7 +119,7 @@ class ContextualSuggestionsMediator implements EnabledStateMonitor.Observer, Fet
     @Override
     public void onEnabledStateChanged(boolean enabled) {
         if (enabled) {
-            mBridge = new SnippetsBridge(mProfile);
+            mSuggestionsSource = new ContextualSuggestionsSource(mProfile);
             mFetchHelper = new FetchHelper(this, mTabModelSelector);
         } else {
             clearSuggestions();
@@ -131,9 +129,9 @@ class ContextualSuggestionsMediator implements EnabledStateMonitor.Observer, Fet
                 mFetchHelper = null;
             }
 
-            if (mBridge != null) {
-                mBridge.destroy();
-                mBridge = null;
+            if (mSuggestionsSource != null) {
+                mSuggestionsSource.destroy();
+                mSuggestionsSource = null;
             }
         }
     }
@@ -141,21 +139,28 @@ class ContextualSuggestionsMediator implements EnabledStateMonitor.Observer, Fet
     @Override
     public void requestSuggestions(String url) {
         mCurrentRequestUrl = url;
-        mBridge.fetchContextualSuggestions(url, (suggestions) -> {
-            if (mBridge == null) return;
+        mSuggestionsSource.getBridge().fetchSuggestions(url, (suggestionsResult) -> {
+            if (mSuggestionsSource == null) return;
 
             // Avoiding double fetches causing suggestions for incorrect context.
             if (!TextUtils.equals(url, mCurrentRequestUrl)) return;
 
-            Toast.makeText(ContextUtils.getApplicationContext(),
-                         suggestions.size() + " suggestions fetched", Toast.LENGTH_SHORT)
-                    .show();
+            List<ContextualSuggestionsCluster> clusters = suggestionsResult.getClusters();
 
-            if (suggestions.size() > 0) {
-                preloadContentInSheet(generateClusterList(suggestions), suggestions.get(0).mTitle);
+            if (clusters.size() > 0 && clusters.get(0).getSuggestions().size() > 0) {
+                Toast.makeText(ContextUtils.getApplicationContext(),
+                             clusters.size() + " clusters fetched", Toast.LENGTH_SHORT)
+                        .show();
+
+                preloadContentInSheet(
+                        generateClusterList(clusters), suggestionsResult.getPeekText());
                 // If the controls are already off-screen, show the suggestions immediately so they
                 // are available on reverse scroll.
                 if (areBrowserControlsHidden()) showContentInSheet();
+            } else {
+                Toast.makeText(ContextUtils.getApplicationContext(), "No suggestions",
+                             Toast.LENGTH_SHORT)
+                        .show();
             }
         });
     }
@@ -185,11 +190,11 @@ class ContextualSuggestionsMediator implements EnabledStateMonitor.Observer, Fet
     }
 
     private void preloadContentInSheet(ClusterList clusters, String title) {
-        if (mBridge == null) return;
+        if (mSuggestionsSource == null) return;
 
         mModel.setClusterList(clusters);
         mModel.setCloseButtonOnClickListener(view -> { clearSuggestions(); });
-        mModel.setTitle(mContext.getString(R.string.contextual_suggestions_toolbar_title, title));
+        mModel.setTitle(title);
         mCoordinator.preloadContentInSheet();
     }
 
@@ -199,7 +204,7 @@ class ContextualSuggestionsMediator implements EnabledStateMonitor.Observer, Fet
         mSheetObserver = new EmptyBottomSheetObserver() {
             @Override
             public void onSheetOpened(@StateChangeReason int reason) {
-                mCoordinator.showSuggestions(mBridge);
+                mCoordinator.showSuggestions(mSuggestionsSource);
                 mCoordinator.removeBottomSheetObserver(this);
                 mSheetObserver = null;
             }
@@ -210,38 +215,46 @@ class ContextualSuggestionsMediator implements EnabledStateMonitor.Observer, Fet
     }
 
     // TODO(twellington): Remove after clusters are returned from the backend.
-    private ClusterList generateClusterList(List<SnippetArticle> suggestions) {
-        List<ContextualSuggestionsCluster> clusters = new ArrayList<>();
+    private ClusterList generateClusterList(List<ContextualSuggestionsCluster> clusters) {
+        if (clusters.size() != 1) {
+            for (ContextualSuggestionsCluster cluster : clusters) {
+                cluster.buildChildren();
+            }
+
+            return new ClusterList(clusters);
+        }
+
+        List<SnippetArticle> suggestions = clusters.get(0).getSuggestions();
+        List<ContextualSuggestionsCluster> newClusters = new ArrayList<>();
         int clusterSize = suggestions.size() >= 6 ? 3 : 2;
         int numClusters = suggestions.size() < 4 ? 1 : suggestions.size() / clusterSize;
         int currentSuggestion = 0;
 
         // Construct a list of clusters.
         for (int i = 0; i < numClusters; i++) {
-            ContextualSuggestionsCluster cluster =
-                    new ContextualSuggestionsCluster(suggestions.get(currentSuggestion).mTitle);
-            if (i == 0) cluster.setShouldShowTitle(false);
+            ContextualSuggestionsCluster cluster = new ContextualSuggestionsCluster(
+                    i != 0 ? suggestions.get(currentSuggestion).mTitle : "");
 
             for (int j = 0; j < clusterSize; j++) {
                 cluster.getSuggestions().add(suggestions.get(currentSuggestion));
                 currentSuggestion++;
             }
 
-            clusters.add(cluster);
+            newClusters.add(cluster);
         }
 
         // Add the remaining suggestions to the last cluster.
         while (currentSuggestion < suggestions.size()) {
-            clusters.get(clusters.size() - 1)
+            newClusters.get(newClusters.size() - 1)
                     .getSuggestions()
                     .add(suggestions.get(currentSuggestion));
             currentSuggestion++;
         }
 
-        for (ContextualSuggestionsCluster cluster : clusters) {
+        for (ContextualSuggestionsCluster cluster : newClusters) {
             cluster.buildChildren();
         }
 
-        return new ClusterList(clusters);
+        return new ClusterList(newClusters);
     }
 }

chrome/android/java/src/org/chromium/chrome/browser/contextual_suggestions/ContextualSuggestionsSource.java

+// Copyright 2018 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.chrome.browser.contextual_suggestions;
+
+import android.graphics.Bitmap;
+
+import org.chromium.base.Callback;
+import org.chromium.chrome.browser.ntp.cards.SuggestionsCategoryInfo;
+import org.chromium.chrome.browser.ntp.snippets.SnippetArticle;
+import org.chromium.chrome.browser.ntp.snippets.SuggestionsSource;
+import org.chromium.chrome.browser.profiles.Profile;
+
+import java.util.List;
+
+/**
+ * Provides content for contextual suggestions.
+ */
+class ContextualSuggestionsSource implements SuggestionsSource {
+    private final ContextualSuggestionsBridge mBridge;
+
+    /**
+     * Creates a ContextualSuggestionsSource for getting contextual suggestions for the current
+     * user.
+     *
+     * @param profile Profile of the user.
+     */
+    ContextualSuggestionsSource(Profile profile) {
+        mBridge = new ContextualSuggestionsBridge(profile);
+    }
+
+    @Override
+    public void destroy() {
+        mBridge.destroy();
+    }
+
+    @Override
+    public void fetchSuggestionImage(SnippetArticle suggestion, Callback<Bitmap> callback) {
+        mBridge.fetchSuggestionImage(suggestion, callback);
+    }
+
+    @Override
+    public void fetchContextualSuggestionImage(
+            SnippetArticle suggestion, Callback<Bitmap> callback) {
+        mBridge.fetchSuggestionImage(suggestion, callback);
+    }
+
+    @Override
+    public void fetchSuggestionFavicon(SnippetArticle suggestion, int minimumSizePx,
+            int desiredSizePx, Callback<Bitmap> callback) {
+        mBridge.fetchSuggestionFavicon(suggestion, callback);
+    }
+
+    /**
+     * @return The {@link ContextualSuggestionsBridge} used communicate with the contextual
+     *         suggestions C++ component.
+     */
+    ContextualSuggestionsBridge getBridge() {
+        return mBridge;
+    }
+
+    // The following methods are not applicable to contextual suggestions.
+    // TODO(twellington): The NTP classes used to display suggestion cards rely
+    // on the SuggestionsSource implementation. Refactor to limit reliance to the
+    // subset of methods actually used to render cards.
+
+    @Override
+    public void fetchRemoteSuggestions() {}
+
+    @Override
+    public boolean areRemoteSuggestionsEnabled() {
+        return false;
+    }
+
+    @Override
+    public int[] getCategories() {
+        return null;
+    }
+
+    @Override
+    public int getCategoryStatus(int category) {
+        return 0;
+    }
+
+    @Override
+    public SuggestionsCategoryInfo getCategoryInfo(int category) {
+        return null;
+    }
+
+    @Override
+    public List<SnippetArticle> getSuggestionsForCategory(int category) {
+        return null;
+    }
+
+    @Override
+    public void fetchSuggestions(int category, String[] displayedSuggestionIds,
+            Callback<List<SnippetArticle>> successCallback, Runnable failureRunnable) {}
+
+    @Override
+    public void fetchContextualSuggestions(String url, Callback<List<SnippetArticle>> callback) {}
+
+    @Override
+    public void dismissSuggestion(SnippetArticle suggestion) {}
+
+    @Override
+    public void dismissCategory(int category) {}
+
+    @Override
+    public void restoreDismissedCategories() {}
+
+    @Override
+    public void addObserver(Observer observer) {}
+
+    @Override
+    public void removeObserver(Observer observer) {}
+}

chrome/android/java/strings/android_chrome_strings.grd

@@ -2447,9 +2447,6 @@ Google may use your browsing activity, content on some sites you visit, and othe
       <message name="IDS_NTP_ALL_DISMISSED_REFRESH" desc="Text label for button to refresh the New Tab Page when all suggested content has been dismissed. [CHAR-LIMIT=20]">
         Refresh
       </message>
-      <message name="IDS_CONTEXTUAL_SUGGESTIONS_TOOLBAR_TITLE" desc="The title displayed above a list of content suggestions based on the user's current webpage. The title tells the user that the list contains more suggestions related to the topic they are currently viewing.">
-        More about <ph name="TOPIC">%1$s<ex>Game of Thrones</ex></ph>
-      </message>
 
       <!-- Toolbar button strings -->
       <message name="IDS_OPEN_TABS" desc="Text for button to enter the tab switcher and show tabs that are open on this device">

chrome/android/java_sources.gni

@@ -301,6 +301,7 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/contextual_suggestions/ContextualSuggestionsCoordinator.java",
   "java/src/org/chromium/chrome/browser/contextual_suggestions/ContextualSuggestionsMediator.java",
   "java/src/org/chromium/chrome/browser/contextual_suggestions/ContextualSuggestionsModel.java",
+  "java/src/org/chromium/chrome/browser/contextual_suggestions/ContextualSuggestionsSource.java",
   "java/src/org/chromium/chrome/browser/contextual_suggestions/DummyEventReporter.java",
   "java/src/org/chromium/chrome/browser/contextual_suggestions/EnabledStateMonitor.java",
   "java/src/org/chromium/chrome/browser/contextual_suggestions/FetchHelper.java",