Add feature flag for early-screen-timeout-detector

Bug: 261744687

Test: adbt build
Change-Id: I305bfe0363a93f0685d5976b3c156227f644ae33
diff --git a/AconfigFlags.bp b/AconfigFlags.bp
index edd9d3a..ce311d0 100644
--- a/AconfigFlags.bp
+++ b/AconfigFlags.bp
@@ -73,6 +73,7 @@
     ":android.provider.flags-aconfig-java{.generated_srcjars}",
     ":android.chre.flags-aconfig-java{.generated_srcjars}",
     ":android.speech.flags-aconfig-java{.generated_srcjars}",
+    ":power_flags_lib{.generated_srcjars}",
 ]
 
 filegroup {
@@ -932,3 +933,10 @@
     aconfig_declarations: "android.speech.flags-aconfig",
     defaults: ["framework-minus-apex-aconfig-java-defaults"],
 }
+
+// Power
+java_aconfig_library {
+    name: "power_flags_lib",
+    aconfig_declarations: "power_flags",
+    defaults: ["framework-minus-apex-aconfig-java-defaults"],
+}
diff --git a/services/core/java/com/android/server/power/PowerManagerService.java b/services/core/java/com/android/server/power/PowerManagerService.java
index 2128c991..e226953 100644
--- a/services/core/java/com/android/server/power/PowerManagerService.java
+++ b/services/core/java/com/android/server/power/PowerManagerService.java
@@ -139,6 +139,7 @@
 import com.android.server.power.batterysaver.BatterySaverPolicy;
 import com.android.server.power.batterysaver.BatterySaverStateMachine;
 import com.android.server.power.batterysaver.BatterySavingStats;
+import com.android.server.power.feature.PowerManagerFlags;
 
 import dalvik.annotation.optimization.NeverCompile;
 
@@ -329,6 +330,8 @@
     // True if battery saver is supported on this device.
     private final boolean mBatterySaverSupported;
 
+    private final PowerManagerFlags mFeatureFlags;
+
     private boolean mDisableScreenWakeLocksWhileCached;
 
     private LightsManager mLightsManager;
@@ -1079,6 +1082,10 @@
         DeviceConfigParameterProvider createDeviceConfigParameterProvider() {
             return new DeviceConfigParameterProvider(DeviceConfigInterface.REAL);
         }
+
+        PowerManagerFlags getFlags() {
+            return new PowerManagerFlags();
+        }
     }
 
     /** Interface for checking an app op permission */
@@ -1145,6 +1152,7 @@
         mNativeWrapper = injector.createNativeWrapper();
         mSystemProperties = injector.createSystemPropertiesWrapper();
         mClock = injector.createClock();
+        mFeatureFlags = injector.getFlags();
         mInjector = injector;
 
         mHandlerThread = new ServiceThread(TAG,
@@ -4802,6 +4810,7 @@
         mAmbientDisplaySuppressionController.dump(pw);
 
         mLowPowerStandbyController.dump(pw);
+        mFeatureFlags.dump(pw);
     }
 
     private void dumpProto(FileDescriptor fd) {
diff --git a/services/core/java/com/android/server/power/feature/Android.bp b/services/core/java/com/android/server/power/feature/Android.bp
new file mode 100644
index 0000000..2295b41
--- /dev/null
+++ b/services/core/java/com/android/server/power/feature/Android.bp
@@ -0,0 +1,7 @@
+aconfig_declarations {
+    name: "power_flags",
+    package: "com.android.server.power.feature.flags",
+    srcs: [
+        "*.aconfig",
+    ],
+}
diff --git a/services/core/java/com/android/server/power/feature/PowerManagerFlags.java b/services/core/java/com/android/server/power/feature/PowerManagerFlags.java
new file mode 100644
index 0000000..a5a7069
--- /dev/null
+++ b/services/core/java/com/android/server/power/feature/PowerManagerFlags.java
@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2023 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.server.power.feature;
+
+import android.text.TextUtils;
+import android.util.Slog;
+
+import com.android.server.power.feature.flags.Flags;
+
+import java.io.PrintWriter;
+import java.util.function.Supplier;
+
+/**
+ * Utility class to read the flags used in the power manager server.
+ */
+public class PowerManagerFlags {
+    private static final boolean DEBUG = false;
+    private static final String TAG = "PowerManagerFlags";
+
+    private final FlagState mEarlyScreenTimeoutDetectorFlagState = new FlagState(
+            Flags.FLAG_ENABLE_EARLY_SCREEN_TIMEOUT_DETECTOR,
+            Flags::enableEarlyScreenTimeoutDetector);
+
+    /** Returns whether early-screen-timeout-detector is enabled on not. */
+    public boolean isEarlyScreenTimeoutDetectorEnabled() {
+        return mEarlyScreenTimeoutDetectorFlagState.isEnabled();
+    }
+
+    /**
+     * dumps all flagstates
+     * @param pw printWriter
+     */
+    public void dump(PrintWriter pw) {
+        pw.println("PowerManagerFlags:");
+        pw.println(" " + mEarlyScreenTimeoutDetectorFlagState);
+    }
+
+    private static class FlagState {
+
+        private final String mName;
+
+        private final Supplier<Boolean> mFlagFunction;
+        private boolean mEnabledSet;
+        private boolean mEnabled;
+
+        private FlagState(String name, Supplier<Boolean> flagFunction) {
+            mName = name;
+            mFlagFunction = flagFunction;
+        }
+
+        private boolean isEnabled() {
+            if (mEnabledSet) {
+                if (DEBUG) {
+                    Slog.d(TAG, mName + ": mEnabled. Recall = " + mEnabled);
+                }
+                return mEnabled;
+            }
+            mEnabled = mFlagFunction.get();
+            if (DEBUG) {
+                Slog.d(TAG, mName + ": mEnabled. Flag value = " + mEnabled);
+            }
+            mEnabledSet = true;
+            return mEnabled;
+        }
+
+        @Override
+        public String toString() {
+            // remove com.android.server.power.feature.flags. from the beginning of the name.
+            // align all isEnabled() values.
+            // Adjust lengths if we end up with longer names
+            final int nameLength = mName.length();
+            return TextUtils.substring(mName,  39, nameLength) + ": "
+                    + TextUtils.formatSimple("%" + (91 - nameLength) + "s%s", " " , isEnabled())
+                    + " (def:" + mFlagFunction.get() + ")";
+        }
+    }
+}
diff --git a/services/core/java/com/android/server/power/feature/power_flags.aconfig b/services/core/java/com/android/server/power/feature/power_flags.aconfig
new file mode 100644
index 0000000..c8c16db
--- /dev/null
+++ b/services/core/java/com/android/server/power/feature/power_flags.aconfig
@@ -0,0 +1,11 @@
+package: "com.android.server.power.feature.flags"
+
+# Important: Flags must be accessed through PowerManagerFlags.
+
+flag {
+    name: "enable_early_screen_timeout_detector"
+    namespace: "power_manager"
+    description: "Feature flag for Early Screen Timeout detector"
+    bug: "309861917"
+    is_fixed_read_only: true
+}