1 files changed, 178 insertions, 0 deletions
diff --git a/mobile/android/base/java/org/mozilla/gecko/GlobalHistory.java b/mobile/android/base/java/org/mozilla/gecko/GlobalHistory.java
new file mode 100644
index 000000000..c1d9c4939
--- /dev/null
+++ b/mobile/android/base/java/org/mozilla/gecko/GlobalHistory.java
@@ -0,0 +1,178 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * 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;
+
+import java.lang.ref.SoftReference;
+import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.Queue;
+import java.util.Set;
+
+import org.mozilla.gecko.db.BrowserDB;
+import org.mozilla.gecko.reader.ReaderModeUtils;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import android.content.ContentResolver;
+import android.content.Context;
+import android.database.Cursor;
+import android.os.Bundle;
+import android.os.Handler;
+import android.os.SystemClock;
+import android.util.Log;
+
+class GlobalHistory {
+    private static final String LOGTAG = "GeckoGlobalHistory";
+
+    public static final String EVENT_URI_AVAILABLE_IN_HISTORY = "URI_INSERTED_TO_HISTORY";
+    public static final String EVENT_PARAM_URI = "uri";
+
+    private static final String TELEMETRY_HISTOGRAM_ADD = "FENNEC_GLOBALHISTORY_ADD_MS";
+    private static final String TELEMETRY_HISTOGRAM_UPDATE = "FENNEC_GLOBALHISTORY_UPDATE_MS";
+    private static final String TELEMETRY_HISTOGRAM_BUILD_VISITED_LINK = "FENNEC_GLOBALHISTORY_VISITED_BUILD_MS";
+
+    private static final GlobalHistory sInstance = new GlobalHistory();
+
+    static GlobalHistory getInstance() {
+        return sInstance;
+    }
+
+    // this is the delay between receiving a URI check request and processing it.
+    // this allows batching together multiple requests and processing them together,
+    // which is more efficient.
+    private static final long BATCHING_DELAY_MS = 100;
+
+    private final Handler mHandler;                     // a background thread on which we can process requests
+
+    //  Note: These fields are accessed through the NotificationRunnable inner class.
+    final Queue<String> mPendingUris;           // URIs that need to be checked
+    SoftReference<Set<String>> mVisitedCache;   // cache of the visited URI list
+    boolean mProcessing; // = false             // whether or not the runnable is queued/working
+
+    private class NotifierRunnable implements Runnable {
+        private final ContentResolver mContentResolver;
+        private final BrowserDB mDB;
+
+        public NotifierRunnable(final Context context) {
+            mContentResolver = context.getContentResolver();
+            mDB = BrowserDB.from(context);
+        }
+
+        @Override
+        public void run() {
+            Set<String> visitedSet = mVisitedCache.get();
+            if (visitedSet == null) {
+                // The cache was wiped. Repopulate it.
+                Log.w(LOGTAG, "Rebuilding visited link set...");
+                final long start = SystemClock.uptimeMillis();
+                final Cursor c = mDB.getAllVisitedHistory(mContentResolver);
+                if (c == null) {
+                    return;
+                }
+
+                try {
+                    visitedSet = new HashSet<String>();
+                    if (c.moveToFirst()) {
+                        do {
+                            visitedSet.add(c.getString(0));
+                        } while (c.moveToNext());
+                    }
+                    mVisitedCache = new SoftReference<Set<String>>(visitedSet);
+                    final long end = SystemClock.uptimeMillis();
+                    final long took = end - start;
+                    Telemetry.addToHistogram(TELEMETRY_HISTOGRAM_BUILD_VISITED_LINK, (int) Math.min(took, Integer.MAX_VALUE));
+                } finally {
+                    c.close();
+                }
+            }
+
+            // This runs on the same handler thread as the checkUriVisited code,
+            // so no synchronization is needed.
+            while (true) {
+                final String uri = mPendingUris.poll();
+                if (uri == null) {
+                    break;
+                }
+
+                if (visitedSet.contains(uri)) {
+                    GeckoAppShell.notifyUriVisited(uri);
+                }
+            }
+
+            mProcessing = false;
+        }
+    };
+
+    private GlobalHistory() {
+        mHandler = ThreadUtils.getBackgroundHandler();
+        mPendingUris = new LinkedList<String>();
+        mVisitedCache = new SoftReference<Set<String>>(null);
+    }
+
+    public void addToGeckoOnly(String uri) {
+        Set<String> visitedSet = mVisitedCache.get();
+        if (visitedSet != null) {
+            visitedSet.add(uri);
+        }
+        GeckoAppShell.notifyUriVisited(uri);
+    }
+
+    public void add(final Context context, final BrowserDB db, String uri) {
+        ThreadUtils.assertOnBackgroundThread();
+        final long start = SystemClock.uptimeMillis();
+
+        // stripAboutReaderUrl only removes about:reader if present, in all other cases the original string is returned
+        final String uriToStore = ReaderModeUtils.stripAboutReaderUrl(uri);
+
+        db.updateVisitedHistory(context.getContentResolver(), uriToStore);
+
+        final long end = SystemClock.uptimeMillis();
+        final long took = end - start;
+        Telemetry.addToHistogram(TELEMETRY_HISTOGRAM_ADD, (int) Math.min(took, Integer.MAX_VALUE));
+        addToGeckoOnly(uriToStore);
+        dispatchUriAvailableMessage(uri);
+    }
+
+    @SuppressWarnings("static-method")
+    public void update(final ContentResolver cr, final BrowserDB db, String uri, String title) {
+        ThreadUtils.assertOnBackgroundThread();
+        final long start = SystemClock.uptimeMillis();
+
+        final String uriToStore = ReaderModeUtils.stripAboutReaderUrl(uri);
+
+        db.updateHistoryTitle(cr, uriToStore, title);
+
+        final long end = SystemClock.uptimeMillis();
+        final long took = end - start;
+        Telemetry.addToHistogram(TELEMETRY_HISTOGRAM_UPDATE, (int) Math.min(took, Integer.MAX_VALUE));
+    }
+
+    public void checkUriVisited(final String uri) {
+        final String storedURI = ReaderModeUtils.stripAboutReaderUrl(uri);
+
+        final NotifierRunnable runnable = new NotifierRunnable(GeckoAppShell.getContext());
+        mHandler.post(new Runnable() {
+            @Override
+            public void run() {
+                // this runs on the same handler thread as the processing loop,
+                // so no synchronization needed
+                mPendingUris.add(storedURI);
+                if (mProcessing) {
+                    // there's already a runnable queued up or working away, so
+                    // no need to post another
+                    return;
+                }
+                mProcessing = true;
+                mHandler.postDelayed(runnable, BATCHING_DELAY_MS);
+            }
+        });
+    }
+
+    private void dispatchUriAvailableMessage(String uri) {
+        final Bundle message = new Bundle();
+        message.putString(EVENT_PARAM_URI, uri);
+        EventDispatcher.getInstance().dispatch(EVENT_URI_AVAILABLE_IN_HISTORY, message);
+    }
+}