root/chrome/android/java/src/org/chromium/chrome/browser/dom_distiller/DomDistillerFeedbackReporter.java

DEFINITIONS

1. JNINamespace
2. setExternalFeedbackReporter
3. reportFeedback
4. isEnabled
5. onYesPressed
6. onNoPressed
7. recordQuality
8. showOverlay
9. dismissOverlay
10. updatePointers
11. createTabObserver
12. nativeIsEnabled
13. nativeReportQuality
14. nativeInit
15. nativeDestroy
16. nativeReplaceWebContents

// Copyright 2014 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.dom_distiller;

import android.app.Activity;

import org.chromium.base.CalledByNative;
import org.chromium.base.JNINamespace;
import org.chromium.chrome.browser.EmptyTabObserver;
import org.chromium.chrome.browser.Tab;
import org.chromium.chrome.browser.TabObserver;
import org.chromium.components.dom_distiller.core.DomDistillerUrlUtils;
import org.chromium.content.browser.ContentView;
import org.chromium.content_public.browser.WebContents;

/**
 * Java implementation of dom_distiller::android::FeedbackReporterAndroid.
 */
@JNINamespace("dom_distiller::android")
public final class DomDistillerFeedbackReporter implements
        DomDistillerFeedbackReportingView.FeedbackObserver {

    private static ExternalFeedbackReporter sExternalFeedbackReporter =
            new NoOpExternalFeedbackReporter();

    public static void setExternalFeedbackReporter(ExternalFeedbackReporter reporter) {
        sExternalFeedbackReporter = reporter;
    }

    private static class NoOpExternalFeedbackReporter implements ExternalFeedbackReporter {
        @Override
        public void reportFeedback(Activity activity, String url, boolean good) {
        }
    }

    private final long mNativePointer;
    private final Tab mTab;

    private ContentView mContentView;
    private DomDistillerFeedbackReportingView mReportingView;

    /**
     * @return whether the DOM Distiller feature is enabled.
     */
    public static boolean isEnabled() {
        return nativeIsEnabled();
    }

    /**
     * Creates the FeedbackReporter, adds itself as a TabObserver, and ensures
     * references to ContentView and WebContents are up to date.
     *
     * @param tab the tab where the overlay should be displayed.
     */
    public DomDistillerFeedbackReporter(Tab tab) {
        mNativePointer = nativeInit();
        mTab = tab;
        mTab.addObserver(createTabObserver());
        updatePointers();
    }

    @Override
    public void onYesPressed(DomDistillerFeedbackReportingView view) {
        if (view != mReportingView) return;
        recordQuality(true);
        dismissOverlay();
    }

    @Override
    public void onNoPressed(DomDistillerFeedbackReportingView view) {
        if (view != mReportingView) return;
        recordQuality(false);
        dismissOverlay();
    }

    /**
     * Records feedback for the distilled content.
     *
     * @param good whether the perceived quality of the distillation of a web page was good.
     */
    private void recordQuality(boolean good) {
        nativeReportQuality(good);
        if (!good) {
            Activity activity = mTab.getWindowAndroid().getActivity().get();
            String url = DomDistillerUrlUtils.getOriginalUrlFromDistillerUrl(mContentView.getUrl());
            sExternalFeedbackReporter.reportFeedback(activity, url, good);
        }
    }

    /**
     * Start showing the overlay.
     */
    @CalledByNative
    private void showOverlay() {
        mReportingView = DomDistillerFeedbackReportingView.create(mContentView, this);
    }

    /**
     * Dismiss the overlay which is currently being displayed.
     */
    @CalledByNative
    private void dismissOverlay() {
        if (mReportingView != null) {
            mReportingView.dismiss(true);
            mReportingView = null;
        }
    }

    /**
     * Updates which ContentView and WebContents the FeedbackReporter is monitoring.
     */
    private void updatePointers() {
        mContentView = mTab.getContentView();
        nativeReplaceWebContents(mNativePointer, mTab.getWebContents());
    }

    /**
     * Creates a TabObserver for monitoring a Tab, used to react to changes in the ContentView
     * or to trigger its own destruction.
     *
     * @return TabObserver that can be used to monitor a Tab.
     */
    private TabObserver createTabObserver() {
        return new EmptyTabObserver() {
            @Override
            public void onWebContentsSwapped(Tab tab, boolean didStartLoad,
                                             boolean didFinishLoad) {
                updatePointers();
            }

            @Override
            public void onContentChanged(Tab tab) {
                updatePointers();
            }

            @Override
            public void onDestroyed(Tab tab) {
                nativeDestroy(mNativePointer);
                mContentView = null;
            }
        };
    }

    private static native boolean nativeIsEnabled();

    private static native void nativeReportQuality(boolean good);

    private native long nativeInit();

    private native void nativeDestroy(long nativeFeedbackReporterAndroid);

    private native void nativeReplaceWebContents(
            long nativeFeedbackReporterAndroid, WebContents webContents);
}