Introduced a group manager to manage group notifications

Bug: 15869874
Change-Id: I1bbcd9e5a2b8dae62bd8d93908dacc5d8fc08887
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationGroupManager.java b/packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationGroupManager.java
new file mode 100644
index 0000000..5214ab4
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationGroupManager.java
@@ -0,0 +1,232 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License
+ */
+
+package com.android.systemui.statusbar.phone;
+
+import android.app.Notification;
+import android.service.notification.StatusBarNotification;
+
+import com.android.systemui.statusbar.ExpandableNotificationRow;
+import com.android.systemui.statusbar.NotificationData;
+import com.android.systemui.statusbar.StatusBarState;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * A class to handle notifications and their corresponding groups.
+ */
+public class NotificationGroupManager {
+
+    private final HashMap<String, NotificationGroup> mGroupMap = new HashMap<>();
+    private OnGroupChangeListener mListener;
+    private int mBarState = -1;
+
+    public void setOnGroupChangeListener(OnGroupChangeListener listener) {
+        mListener = listener;
+    }
+
+    public boolean isGroupExpanded(StatusBarNotification sbn) {
+        NotificationGroup group = mGroupMap.get(sbn.getGroupKey());
+        if (group == null) {
+            return false;
+        }
+        return group.expanded;
+    }
+
+    public void setGroupExpanded(StatusBarNotification sbn, boolean expanded) {
+        NotificationGroup group = mGroupMap.get(sbn.getGroupKey());
+        if (group == null) {
+            return;
+        }
+        setGroupExpanded(group, expanded);
+    }
+
+    private void setGroupExpanded(NotificationGroup group, boolean expanded) {
+        group.expanded = expanded;
+        if (group.summary != null) {
+            mListener.onGroupExpansionChanged(group.summary.row, expanded);
+        }
+    }
+
+    public void onEntryRemoved(NotificationData.Entry removed) {
+        onEntryRemovedInternal(removed, removed.notification);
+    }
+
+    /**
+     * An entry was removed.
+     *
+     * @param removed the removed entry
+     * @param sbn the notification the entry has, which doesn't need to be the same as it's internal
+     *            notification
+     */
+    private void onEntryRemovedInternal(NotificationData.Entry removed,
+            final StatusBarNotification sbn) {
+        Notification notif = sbn.getNotification();
+        String groupKey = sbn.getGroupKey();
+        final NotificationGroup group = mGroupMap.get(groupKey);
+        if (notif.isGroupSummary()) {
+            group.summary = null;
+        } else {
+            group.children.remove(removed);
+        }
+        if (group.children.isEmpty()) {
+            if (group.summary == null) {
+                mGroupMap.remove(groupKey);
+            } else {
+                if (group.expanded) {
+                    // only the summary is left. Change it to unexpanded in a few ms. We do this to
+                    // avoid raceconditions
+                    removed.row.post(new Runnable() {
+                        @Override
+                        public void run() {
+                            if (group.children.isEmpty()) {
+                                setGroupExpanded(sbn, false);
+                            }
+                        }
+                    });
+                }
+            }
+        }
+    }
+
+    public void onEntryAdded(NotificationData.Entry added) {
+        StatusBarNotification sbn = added.notification;
+        Notification notif = sbn.getNotification();
+        String groupKey = sbn.getGroupKey();
+        NotificationGroup group = mGroupMap.get(groupKey);
+        if (group == null) {
+            group = new NotificationGroup();
+            mGroupMap.put(groupKey, group);
+        }
+        if (notif.isGroupSummary()) {
+            group.summary = added;
+            if (!group.children.isEmpty()) {
+                mListener.onGroupCreatedFromChildren(group);
+            }
+        } else {
+            group.children.add(added);
+        }
+    }
+
+    public void onEntryUpdated(NotificationData.Entry entry,
+            StatusBarNotification oldNotification) {
+        if (mGroupMap.get(oldNotification.getGroupKey()) != null) {
+            onEntryRemovedInternal(entry, oldNotification);
+        }
+        onEntryAdded(entry);
+    }
+
+    public boolean isVisible(StatusBarNotification sbn) {
+        if (!sbn.getNotification().isGroupChild()) {
+            return true;
+        }
+        NotificationGroup group = mGroupMap.get(sbn.getGroupKey());
+        if (group != null && group.expanded) {
+            return true;
+        }
+        return false;
+    }
+
+    public boolean hasGroupChildren(StatusBarNotification sbn) {
+        if (areGroupsProhibited()) {
+            return false;
+        }
+        if (!sbn.getNotification().isGroupSummary()) {
+            return false;
+        }
+        NotificationGroup group = mGroupMap.get(sbn.getGroupKey());
+        if (group == null) {
+            return false;
+        }
+        return !group.children.isEmpty();
+    }
+
+    public void setStatusBarState(int newState) {
+        if (mBarState == newState) {
+            return;
+        }
+        boolean prohibitedBefore = areGroupsProhibited();
+        mBarState = newState;
+        boolean nowProhibited = areGroupsProhibited();
+        if (nowProhibited != prohibitedBefore) {
+            if (nowProhibited) {
+                for (NotificationGroup group : mGroupMap.values()) {
+                    if (group.expanded) {
+                        setGroupExpanded(group, false);
+                    }
+                }
+            }
+            mListener.onGroupsProhibitedChanged();
+        }
+    }
+
+    private boolean areGroupsProhibited() {
+        return mBarState == StatusBarState.KEYGUARD;
+    }
+
+    /**
+     * @return whether a given notification is a child in a group which has a summary
+     */
+    public boolean isChildInGroupWithSummary(StatusBarNotification sbn) {
+        if (!sbn.getNotification().isGroupChild()) {
+            return false;
+        }
+        NotificationGroup group = mGroupMap.get(sbn.getGroupKey());
+        if (group == null || group.summary == null) {
+            return false;
+        }
+        return true;
+    }
+
+    public ExpandableNotificationRow getGroupSummary(StatusBarNotification sbn) {
+        NotificationGroup group = mGroupMap.get(sbn.getGroupKey());
+        return group == null ? null
+                : group.summary == null ? null
+                : group.summary.row;
+    }
+
+    public static class NotificationGroup {
+        public final HashSet<NotificationData.Entry> children = new HashSet<>();
+        public NotificationData.Entry summary;
+        public boolean expanded;
+    }
+
+    public interface OnGroupChangeListener {
+        /**
+         * The expansion of a group has changed.
+         *
+         * @param changedRow the row for which the expansion has changed, which is also the summary
+         * @param expanded a boolean indicating the new expanded state
+         */
+        void onGroupExpansionChanged(ExpandableNotificationRow changedRow, boolean expanded);
+
+        /**
+         * Children group policy has changed and children may no be prohibited or allowed.
+         */
+        void onGroupsProhibitedChanged();
+
+        /**
+         * A group of children just received a summary notification and should therefore become
+         * children of it.
+         *
+         * @param group the group created
+         */
+        void onGroupCreatedFromChildren(NotificationGroup group);
+    }
+}