Add summary text to App permissions settings.

Check the granted permissions for the installed app and compose the
summary text to use the first 3 permissions granted from the list:
Location, Microphone, Camera, Sms, Contacts, and Phone.

Change-Id: I61d21f279af2fe86132de22b94e1a49da0225fcd
Fix: 36376411
Test: make RunSettingsRoboTests

src/com/android/settings/applications/AppPermissionsPreferenceController.java

@@ -0,0 +1,143 @@
+/*
+ * Copyright (C) 2017 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.settings.applications;
+
+import android.content.Context;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.PackageManager.NameNotFoundException;
+import android.content.pm.PermissionGroupInfo;
+import android.content.pm.PermissionInfo;
+import android.support.v7.preference.Preference;
+import android.text.TextUtils;
+import android.util.ArraySet;
+import android.util.Log;
+import com.android.settings.R;
+import com.android.settings.core.PreferenceController;
+import java.util.List;
+import java.util.Set;
+
+public class AppPermissionsPreferenceController extends PreferenceController {
+
+    private static final String TAG = "AppPermissionPrefCtrl";
+    private static final String KEY_APP_PERMISSION_GROUPS = "manage_perms";
+    private static final String[] PERMISSION_GROUPS = new String[] {
+        "android.permission-group.LOCATION",
+        "android.permission-group.MICROPHONE",
+        "android.permission-group.CAMERA",
+        "android.permission-group.SMS",
+        "android.permission-group.CONTACTS",
+        "android.permission-group.PHONE"};
+
+    private static final int NUM_PERMISSION_TO_USE = 3;
+
+    private final PackageManager mPackageManager;
+
+    public AppPermissionsPreferenceController(Context context) {
+        super(context);
+        mPackageManager = context.getPackageManager();
+    }
+
+    @Override
+    public boolean isAvailable() {
+        return true;
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return KEY_APP_PERMISSION_GROUPS;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        final String summary = getSummary();
+        if (summary != null) {
+            preference.setSummary(summary);
+        }
+    }
+
+    /*
+       Summary text looks like: Apps using Permission1, Permission2, Permission3
+       The 3 permissions are the first three from the list which any app has granted:
+       Location, Microphone, Camera, Sms, Contacts, and Phone
+     */
+    private String getSummary() {
+        final Set<String> permissions = getAllPermissionsInGroups();
+        Set<String> grantedPermissionGroups = getGrantedPermissionGroups(permissions);
+        CharSequence summary = null;
+        int count = 0;
+        for (String group : PERMISSION_GROUPS) {
+            if (!grantedPermissionGroups.contains(group)) {
+                continue;
+            }
+            summary = concatSummaryText(summary, group);
+            if (++count >= NUM_PERMISSION_TO_USE) {
+                break;
+            }
+        }
+        return count > 0 ? mContext.getString(R.string.app_permissions_summary, summary) : null;
+    }
+
+    private Set<String> getGrantedPermissionGroups(Set<String> permissions) {
+        ArraySet<String> grantedPermissionGroups = new ArraySet<>();
+        List<PackageInfo> installedPackages =
+            mPackageManager.getInstalledPackages(PackageManager.GET_PERMISSIONS);
+        for (PackageInfo installedPackage : installedPackages) {
+            if (installedPackage.permissions == null) {
+                continue;
+            }
+            for (PermissionInfo permissionInfo : installedPackage.permissions) {
+                if (permissions.contains(permissionInfo.name)
+                        && !grantedPermissionGroups.contains(permissionInfo.group)) {
+                    grantedPermissionGroups.add(permissionInfo.group);
+                }
+            }
+        }
+        return grantedPermissionGroups;
+    }
+
+    private CharSequence concatSummaryText(CharSequence currentSummary, String permission) {
+        final CharSequence label = getPermissionGroupLabel(permission);
+        if (TextUtils.isEmpty(currentSummary)) {
+            return label;
+        }
+        return mContext.getString(R.string.join_many_items_middle, currentSummary, label);
+    }
+
+    private CharSequence getPermissionGroupLabel(String group) {
+        try {
+            final PermissionGroupInfo groupInfo = mPackageManager.getPermissionGroupInfo(group, 0);
+            return groupInfo.loadLabel(mPackageManager);
+        } catch (NameNotFoundException e) {
+            Log.e(TAG, "Error getting permissions label.", e);
+        }
+        return group;
+    }
+
+    private Set<String> getAllPermissionsInGroups() {
+        ArraySet<String> result = new ArraySet<>();
+        for (String group : PERMISSION_GROUPS) {
+            try {
+                final List<PermissionInfo> permissions =
+                    mPackageManager.queryPermissionsByGroup(group, 0);
+                for (PermissionInfo permissionInfo : permissions) {
+                    result.add(permissionInfo.name);
+                }
+            } catch (NameNotFoundException e) {
+                Log.e(TAG, "Error getting permissions in group "+group, e);
+            }
+        }
+        return result;
+    }
+}