[Offline Page] Offline page sharing implementation

chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageUtils.java

 // 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.chrome.browser.offlinepages;
 
+import android.app.Activity;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.graphics.Bitmap;
+import android.net.Uri;
+import android.os.AsyncTask;
 import android.os.BatteryManager;
 import android.os.Environment;
 
+import org.chromium.base.Callback;
 import org.chromium.base.Log;
 import org.chromium.base.VisibleForTesting;
 import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.base.metrics.RecordUserAction;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ChromeActivity;
 import org.chromium.chrome.browser.profiles.Profile;
+import org.chromium.chrome.browser.share.ShareHelper;
 import org.chromium.chrome.browser.snackbar.Snackbar;
 import org.chromium.chrome.browser.snackbar.SnackbarManager;
 import org.chromium.chrome.browser.snackbar.SnackbarManager.SnackbarController;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.components.bookmarks.BookmarkId;
 import org.chromium.content_public.browser.LoadUrlParams;
 import org.chromium.content_public.browser.WebContents;
 import org.chromium.net.ConnectionType;
 import org.chromium.net.NetworkChangeNotifier;
 import org.chromium.ui.base.PageTransition;
 
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.nio.channels.FileChannel;
 import java.util.concurrent.TimeUnit;
 
 /**
  * A class holding static util functions for offline pages.
  */
 public class OfflinePageUtils {
     private static final String TAG = "OfflinePageUtils";
     /** Background task tag to differentiate from other task types */
     public static final String TASK_TAG = "OfflinePageUtils";
 
+    public static final String EXTERNAL_MHTML_FILE_PATH = "offline-pages";
+
     private static final int SNACKBAR_DURATION = 6 * 1000; // 6 second
 
     private static final long STORAGE_ALMOST_FULL_THRESHOLD_BYTES = 10L * (1 << 20); // 10M
 
     private static OfflinePageUtils sInstance;
 
     private static OfflinePageUtils getInstance() {
         if (sInstance == null) {
             sInstance = new OfflinePageUtils();
         }
@@ skipping 191 matching lines @@
         long delayInMilliseconds = nowMillis - taskScheduledTimeMillis;
         if (delayInMilliseconds <= 0) {
             return;
         }
         RecordHistogram.recordLongTimesHistogram(
                 "OfflinePages.Wakeup.DelayTime",
                 delayInMilliseconds,
                 TimeUnit.MILLISECONDS);
     }
 
+    /**
+     * Share saved offline page.
+     * @param shareDirectly Whether it should share directly with the activity that was most
+     *                      recently used to share.
+     * @param mainActivity Activity that is used to access package manager
+     * @param onlineUrl Online URL associated with the offline page that is used to access the
+     *                  offline page file path.
+     * @param bitmap Screenshot of the page to be shared.
+     * @param mContext The application context.
+     * @param currentTab Tab that is used to access offlineUrl and tile.
+     */
+    public static void shareOfflinePage(final boolean shareDirectly, final Activity mainActivity,
+            final String onlineUrl, final Bitmap bitmap, final Context mContext,
+            final Tab currentTab) {
+        final String offlineUrl = currentTab.getUrl();
+        final String title = currentTab.getTitle();
+        OfflinePageBridge offlinePageBridge =
+                OfflinePageBridge.getForProfile(currentTab.getProfile());
+        if (offlinePageBridge != null) {
+            offlinePageBridge.getPageByOfflineUrl(offlineUrl, new Callback<OfflinePageItem>() {
+                @Override
+                public void onResult(OfflinePageItem item) {
+                    if (item != null) {
+                        String offlineFilePath = item.getFilePath();
+                        prepareForSharing(shareDirectly, mainActivity, title, onlineUrl, bitmap,
+                                offlineFilePath, mContext);
+                    }
+                }
+            });
+        } else {
+            Log.e(TAG, "Unable to perform sharing on current tab.");
+        }
+    }
+
+    private static void prepareForSharing(final boolean shareDirectly, final Activity activity,
+            final String title, final String onlineUrl, final Bitmap bitmap, final String filePath,
+            final Context context) {
+        new AsyncTask<Void, Void, File>() {
+            @Override
+            protected File doInBackground(Void... params) {
+                File offlinePageOriginal = new File(filePath);
+                File shareableDir = getDirectoryForOfflineSharing(context);
+                if (shareableDir != null) {
+                    String fileName = rewriteOfflineFileName(offlinePageOriginal.getName());
+                    File offlinePageShareable = new File(shareableDir, fileName);
+
+                    if (offlinePageShareable.exists()) {
+                        try {
+                            offlinePageShareable.delete();
+                        } catch (SecurityException e) {
+                            Log.e(TAG,
+                                    "failed to delete the file: " + offlinePageOriginal.getName());
+                        }
+                    }
+                    if (copyToShareableLocation(offlinePageOriginal, offlinePageShareable)) {
+                        return offlinePageShareable;
+                    }
+                } else {
+                    Log.e(TAG, "Unable to create subdirectory in shareable directory");
+                }
+                return null;
+            }
+
+            @Override
+            protected void onPostExecute(File offlinePageShareable) {
+                if (offlinePageShareable == null) return;
+                Uri offlineUri = Uri.fromFile(offlinePageShareable);
+                ShareHelper.share(shareDirectly, activity, title, onlineUrl, offlineUri, bitmap);
+            }
+        }.execute();
+    }
+
+    /**
+     * This method copies the file from internal storage to a sharable directory.
+     * @param src file path of the original file to be copied
+     * @param dst file path of the destination
+     */
+    @VisibleForTesting
+    static boolean copyToShareableLocation(File src, File dst) {
+        try {
+            FileChannel inChannel = new FileInputStream(src).getChannel();
+            FileChannel outChannel = new FileOutputStream(dst).getChannel();
+
+            inChannel.transferTo(0, inChannel.size(), outChannel);
+
+            if (inChannel != null) inChannel.close();
+            if (outChannel != null) outChannel.close();
+        } catch (FileNotFoundException e) {
+            Log.e(TAG, "failed to copy the file: " + src.getName() + ", " + e);
+            return false;
+        } catch (IOException e) {
+            Log.e(TAG, "failed to copy the file: " + src.getName() + ", " + e);
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Get a directory for offline page sharing operation.
+     * @param context Context that is used to access external cache directory.
+     * @return path to directory for the shared file to be stored
+     * */

[fgorski, 2016/08/11 16:57:53]

nit: * still needs removing 

[Vivian, 2016/08/11 23:18:29]

Done.

+    private static File getDirectoryForOfflineSharing(Context context) {
+        File path = new File(context.getExternalCacheDir(), EXTERNAL_MHTML_FILE_PATH);
+        boolean success = true;
+        if (!path.exists() && !path.mkdir()) {
+            path = null;
+        }
+        return path;
+    }
+
+    /**
+     * Rewrite file name so that it does not contain periods except the one to separate the file
+     * extension.
+     * This step is used to ensure that file name can be recognized by intent filter (.*\\.mhtml").
+     * As Android's path pattern only matches the first dot that appears in a file path.
+     * @pram fileName Name of the offline page file.
+     */
+    @VisibleForTesting
+    static String rewriteOfflineFileName(String fileName) {
+        fileName = fileName.replaceAll("\\s+", "");
+        return fileName.replaceAll("\\.(?=.*\\.)", "_");
+    }
+
+    /**
+     * Delete a shared mhtml file. If the file path is a directory, delete all files in directory.
+     * @param file File object of the offline page.
+     */
+    @VisibleForTesting
+    static void deleteSharedOfflineFiles(File file) {
+        if (!file.exists()) return;
+        if (file.isDirectory()) {
+            for (File f : file.listFiles()) deleteSharedOfflineFiles(f);
+        }
+        if (!file.delete()) {
+            Log.w(TAG, "Failed to delete shared offline file: %s", file.getAbsolutePath());
+        }
+    }
+
+    /**
+     * Clears all shared mhtml files.
+     * @param context Context that is used to access external cache directory.
+     */
+    public static void clearSharedOfflineFiles(final Context context) {
+        new AsyncTask<Void, Void, Void>() {
+            @Override
+            protected Void doInBackground(Void... params) {
+                File offlinePath = getDirectoryForOfflineSharing(context);
+                deleteSharedOfflineFiles(offlinePath);
+                return null;
+            }
+        }.execute();
+    }
+
     private static boolean isPowerConnected(Intent batteryStatus) {
         int status = batteryStatus.getIntExtra(BatteryManager.EXTRA_STATUS, -1);
         boolean isConnected = (status == BatteryManager.BATTERY_STATUS_CHARGING
                 || status == BatteryManager.BATTERY_STATUS_FULL);
         Log.d(TAG, "Power connected is " + isConnected);
         return isConnected;
     }
 
     private static int batteryPercentage(Intent batteryStatus) {
         int level = batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
@@ skipping 20 matching lines @@
         return new DeviceConditions(isPowerConnected(batteryStatus),
                 batteryPercentage(batteryStatus),
                 NetworkChangeNotifier.getInstance().getCurrentConnectionType());
     }
 
     @VisibleForTesting
     static void setInstanceForTesting(OfflinePageUtils instance) {
         sInstance = instance;
     }
 }