From 53aaab09b8592220cfe850797000c757d32236da Mon Sep 17 00:00:00 2001
From: Kevin Han <kevhan@google.com>
Date: Fri, 7 May 2021 12:07:43 -0700
Subject: [PATCH] Fix "X unused apps" string to match w/ unused apps

This fixes an issue where there is some discrepancy between the "X
unused apps" string in Settings and the actual number of unused apps in
PermissionController due to the Settings logic not taking into account
the usage time.

Bug: 187464720
Test: atest HibernatedAppsPreferenceControllerTest
Test: hibernate app and revoke permission, open app, number of unused
apps matches up

Change-Id: Ifc30280e582e4183c61d421dd5378d627a80baf9
---
 .../HibernatedAppsPreferenceController.java   | 30 ++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/src/com/android/settings/applications/HibernatedAppsPreferenceController.java b/src/com/android/settings/applications/HibernatedAppsPreferenceController.java
index 4088d3a0c00..8d128112ad7 100644
--- a/src/com/android/settings/applications/HibernatedAppsPreferenceController.java
+++ b/src/com/android/settings/applications/HibernatedAppsPreferenceController.java
@@ -16,26 +16,35 @@
 
 package com.android.settings.applications;
 
+import static android.app.usage.UsageStatsManager.INTERVAL_MONTHLY;
 import static android.provider.DeviceConfig.NAMESPACE_APP_HIBERNATION;
 
 import static com.android.settings.Utils.PROPERTY_APP_HIBERNATION_ENABLED;
 
+import android.app.usage.UsageStats;
+import android.app.usage.UsageStatsManager;
 import android.apphibernation.AppHibernationManager;
 import android.content.Context;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
 import android.provider.DeviceConfig;
+import android.util.ArrayMap;
 
 import com.android.settings.R;
 import com.android.settings.core.BasePreferenceController;
 
 import java.util.List;
+import java.util.Map;
+import java.util.concurrent.TimeUnit;
 
 /**
  * A preference controller handling the logic for updating summary of hibernated apps.
  */
 public final class HibernatedAppsPreferenceController extends BasePreferenceController {
     private static final String TAG = "HibernatedAppsPrefController";
+    private static final String PROPERTY_HIBERNATION_UNUSED_THRESHOLD_MILLIS =
+            "auto_revoke_unused_threshold_millis2";
+    private static final long DEFAULT_UNUSED_THRESHOLD_MS = TimeUnit.DAYS.toMillis(90);
 
     public HibernatedAppsPreferenceController(Context context, String preferenceKey) {
         super(context, preferenceKey);
@@ -55,17 +64,36 @@ public final class HibernatedAppsPreferenceController extends BasePreferenceCont
     }
 
     private int getNumHibernated() {
+        // TODO(b/187465752): Find a way to export this logic from PermissionController module
         final PackageManager pm = mContext.getPackageManager();
         final AppHibernationManager ahm = mContext.getSystemService(AppHibernationManager.class);
         final List<String> hibernatedPackages = ahm.getHibernatingPackagesForUser();
         int numHibernated = hibernatedPackages.size();
 
         // Also need to count packages that are auto revoked but not hibernated.
+        final UsageStatsManager usm = mContext.getSystemService(UsageStatsManager.class);
+        final long now = System.currentTimeMillis();
+        final long unusedThreshold = DeviceConfig.getLong(DeviceConfig.NAMESPACE_PERMISSIONS,
+                PROPERTY_HIBERNATION_UNUSED_THRESHOLD_MILLIS, DEFAULT_UNUSED_THRESHOLD_MS);
+        final List<UsageStats> usageStatsList = usm.queryUsageStats(INTERVAL_MONTHLY,
+                now - unusedThreshold, now);
+        final Map<String, UsageStats> recentlyUsedPackages = new ArrayMap<>();
+        for (UsageStats us : usageStatsList) {
+            recentlyUsedPackages.put(us.mPackageName, us);
+        }
         final List<PackageInfo> packages = pm.getInstalledPackages(
                 PackageManager.MATCH_DISABLED_COMPONENTS | PackageManager.GET_PERMISSIONS);
         for (PackageInfo pi : packages) {
             final String packageName = pi.packageName;
-            if (!hibernatedPackages.contains(packageName) && pi.requestedPermissions != null) {
+            final UsageStats usageStats = recentlyUsedPackages.get(packageName);
+            // Only count packages that have not been used recently as auto-revoked permissions may
+            // stay revoked even after use if the user has not regranted them.
+            final boolean usedRecently = (usageStats != null
+                    && (now - usageStats.getLastTimeAnyComponentUsed() < unusedThreshold
+                        || now - usageStats.getLastTimeVisible() < unusedThreshold));
+            if (!hibernatedPackages.contains(packageName)
+                    && pi.requestedPermissions != null
+                    && !usedRecently) {
                 for (String perm : pi.requestedPermissions) {
                     if ((pm.getPermissionFlags(perm, packageName, mContext.getUser())
                             & PackageManager.FLAG_PERMISSION_AUTO_REVOKED) != 0) {