Add filtering for Presence data.

Bug: 195695593
Test: atest NearbyUnitTests
Change-Id: I86a2d4cdb58334056eda1e553bc70236c03905fb
diff --git a/nearby/framework/java/android/nearby/NearbyDeviceParcelable.java b/nearby/framework/java/android/nearby/NearbyDeviceParcelable.java
index 3b0a776..e9a29b7 100644
--- a/nearby/framework/java/android/nearby/NearbyDeviceParcelable.java
+++ b/nearby/framework/java/android/nearby/NearbyDeviceParcelable.java
@@ -76,6 +76,8 @@
                     return new NearbyDeviceParcelable[size];
                 }
             };
+
+    @ScanRequest.ScanType int mScanType;
     @Nullable
     private final String mName;
     @NearbyDevice.Medium
@@ -89,9 +91,10 @@
     @Nullable
     private final byte[] mData;
 
-    private NearbyDeviceParcelable(@Nullable String name, int medium, int rssi,
-            @Nullable String fastPairModelId, @Nullable String bluetoothAddress,
-            @Nullable byte[] data) {
+    private NearbyDeviceParcelable(@ScanRequest.ScanType int scanType, @Nullable String name,
+            int medium, int rssi, @Nullable String fastPairModelId,
+            @Nullable String bluetoothAddress, @Nullable byte[] data) {
+        mScanType = scanType;
         mName = name;
         mMedium = medium;
         mRssi = rssi;
@@ -176,6 +179,16 @@
     }
 
     /**
+     * Returns the type of the scan.
+     *
+     * @hide
+     */
+    @ScanRequest.ScanType
+    public int getScanType() {
+        return mScanType;
+    }
+
+    /**
      * Gets the name of the NearbyDeviceParcelable. Returns {@code null} If there is no name.
      */
     @Nullable
@@ -235,6 +248,7 @@
         @NearbyDevice.Medium
         private int mMedium;
         private int mRssi;
+        @ScanRequest.ScanType int mScanType;
         @Nullable
         private String mFastPairModelId;
         @Nullable
@@ -243,6 +257,16 @@
         private byte[] mData;
 
         /**
+         * Sets the scan type of the NearbyDeviceParcelable.
+         *
+         * @hide
+         */
+        public Builder setScanType(@ScanRequest.ScanType int scanType) {
+            mScanType = scanType;
+            return this;
+        }
+
+        /**
          * Sets the name of the scanned device.
          *
          * @param name The local name of the scanned device.
@@ -314,7 +338,7 @@
          */
         @NonNull
         public NearbyDeviceParcelable build() {
-            return new NearbyDeviceParcelable(mName, mMedium, mRssi, mFastPairModelId,
+            return new NearbyDeviceParcelable(mScanType, mName, mMedium, mRssi, mFastPairModelId,
                     mBluetoothAddress, mData);
         }
     }
diff --git a/nearby/service/java/com/android/server/nearby/presence/PresenceConstants.java b/nearby/service/java/com/android/server/nearby/presence/PresenceConstants.java
new file mode 100644
index 0000000..c355df2
--- /dev/null
+++ b/nearby/service/java/com/android/server/nearby/presence/PresenceConstants.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2022 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.nearby.presence;
+
+import static com.android.server.nearby.common.bluetooth.fastpair.BluetoothUuids.to128BitUuid;
+
+import java.util.UUID;
+
+/**
+ * Constants for Nearby Presence operations.
+ */
+public class PresenceConstants {
+
+    /** Presence advertisement service data uuid. */
+    public static final UUID PRESENCE_UUID = to128BitUuid((short) 0xFCF1);
+}
diff --git a/nearby/service/java/com/android/server/nearby/presence/PresenceDiscoveryResult.java b/nearby/service/java/com/android/server/nearby/presence/PresenceDiscoveryResult.java
new file mode 100644
index 0000000..7a77aa9
--- /dev/null
+++ b/nearby/service/java/com/android/server/nearby/presence/PresenceDiscoveryResult.java
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2022 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.nearby.presence;
+
+import android.nearby.NearbyDevice;
+import android.nearby.PresenceDevice;
+import android.nearby.PresenceScanFilter;
+import android.nearby.PublicCredential;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Represents a Presence discovery result.
+ */
+public class PresenceDiscoveryResult {
+
+    /**
+     * Creates a {@link PresenceDiscoveryResult} from the scan data.
+     */
+    public static PresenceDiscoveryResult fromScanData(byte[] scanData, int rssi) {
+        return new PresenceDiscoveryResult.Builder().setRssi(rssi).build();
+    }
+
+    private final int mTxPower;
+    private final int mRssi;
+    private final byte[] mSalt;
+    private final List<Integer> mPresenceActions;
+    private final PublicCredential mPublicCredential;
+
+    private PresenceDiscoveryResult(int txPower, int rssi, byte[] salt,
+            List<Integer> presenceActions, PublicCredential publicCredential) {
+        mTxPower = txPower;
+        mRssi = rssi;
+        mSalt = salt;
+        mPresenceActions = presenceActions;
+        mPublicCredential = publicCredential;
+    }
+
+    /**
+     * Returns whether the discovery result matches the scan filter.
+     */
+    public boolean matches(PresenceScanFilter scanFilter) {
+        return pathLossMatches(scanFilter.getMaxPathLoss())
+                && actionMatches(scanFilter.getPresenceActions())
+                && credentialMatches(scanFilter.getCredentials());
+    }
+
+    private boolean pathLossMatches(int maxPathLoss) {
+        return (mTxPower - mRssi) <= maxPathLoss;
+    }
+
+    private boolean actionMatches(List<Integer> filterActions) {
+        if (filterActions.isEmpty()) {
+            return true;
+        }
+        return filterActions.stream().anyMatch(mPresenceActions::contains);
+    }
+
+    private boolean credentialMatches(List<PublicCredential> credentials) {
+        return credentials.contains(mPublicCredential);
+    }
+
+    /**
+     * Converts a presence device from the discovery result.
+     */
+    public PresenceDevice toPresenceDevice() {
+        return new PresenceDevice.Builder()
+                .setRssi(mRssi)
+                .setSalt(mSalt)
+                .setSecretId(mPublicCredential.getSecretId())
+                .addMedium(NearbyDevice.Medium.BLE).build();
+    }
+
+    /**
+     * Builder for {@link PresenceDiscoveryResult}.
+     */
+    public static class Builder {
+        private int mTxPower;
+        private int mRssi;
+        private byte[] mSalt;
+
+        private PublicCredential mPublicCredential;
+        private final List<Integer> mPresenceActions;
+
+        public Builder() {
+            mPresenceActions = new ArrayList<>();
+        }
+
+        /**
+         * Sets the calibrated tx power for the discovery result.
+         */
+        public Builder setTxPower(int txPower) {
+            mTxPower = txPower;
+            return this;
+        }
+
+        /**
+         * Sets the rssi for the discovery result.
+         */
+        public Builder setRssi(int rssi) {
+            mRssi = rssi;
+            return this;
+        }
+
+        /**
+         * Sets the salt for the discovery result.
+         */
+        public Builder setSalt(byte[] salt) {
+            mSalt = salt;
+            return this;
+        }
+
+        /**
+         * Sets the public credential for the discovery result.
+         */
+        public Builder setPublicCredential(PublicCredential publicCredential) {
+            mPublicCredential = publicCredential;
+            return this;
+        }
+
+        /**
+         * Adds presence action of the discovery result.
+         */
+        public Builder addPresenceAction(int presenceAction) {
+            mPresenceActions.add(presenceAction);
+            return this;
+        }
+
+        /**
+         * Builds a {@link PresenceDiscoveryResult}.
+         */
+        public PresenceDiscoveryResult build() {
+            return new PresenceDiscoveryResult(mTxPower, mRssi, mSalt, mPresenceActions,
+                    mPublicCredential);
+        }
+    }
+}
diff --git a/nearby/service/java/com/android/server/nearby/provider/BleDiscoveryProvider.java b/nearby/service/java/com/android/server/nearby/provider/BleDiscoveryProvider.java
index ae7f133..fc2e4e8 100644
--- a/nearby/service/java/com/android/server/nearby/provider/BleDiscoveryProvider.java
+++ b/nearby/service/java/com/android/server/nearby/provider/BleDiscoveryProvider.java
@@ -34,6 +34,7 @@
 
 import com.android.server.nearby.common.bluetooth.fastpair.Constants;
 import com.android.server.nearby.injector.Injector;
+import com.android.server.nearby.presence.PresenceConstants;
 import com.android.server.nearby.util.ForegroundThread;
 
 import java.util.ArrayList;
@@ -47,6 +48,8 @@
 public class BleDiscoveryProvider extends AbstractDiscoveryProvider {
 
     private static final ParcelUuid FAST_PAIR_UUID = new ParcelUuid(Constants.FastPairService.ID);
+    private static final ParcelUuid PRESENCE_UUID = new ParcelUuid(PresenceConstants.PRESENCE_UUID);
+
     // Don't block the thread as it may be used by other services.
     private static final Executor NEARBY_EXECUTOR = ForegroundThread.getExecutor();
     private final Injector mInjector;
@@ -69,6 +72,11 @@
                         byte[] fastPairData = serviceDataMap.get(FAST_PAIR_UUID);
                         if (fastPairData != null) {
                             builder.setData(serviceDataMap.get(FAST_PAIR_UUID));
+                        } else {
+                            byte [] presenceData = serviceDataMap.get(PRESENCE_UUID);
+                            if (presenceData != null) {
+                                builder.setData(serviceDataMap.get(PRESENCE_UUID));
+                            }
                         }
                     }
                     mExecutor.execute(() -> mListener.onNearbyDeviceDiscovered(builder.build()));
diff --git a/nearby/service/java/com/android/server/nearby/provider/DiscoveryProviderManager.java b/nearby/service/java/com/android/server/nearby/provider/DiscoveryProviderManager.java
index 27f3acb..825a4ab 100644
--- a/nearby/service/java/com/android/server/nearby/provider/DiscoveryProviderManager.java
+++ b/nearby/service/java/com/android/server/nearby/provider/DiscoveryProviderManager.java
@@ -16,11 +16,15 @@
 
 package com.android.server.nearby.provider;
 
+import static android.nearby.ScanRequest.SCAN_TYPE_NEARBY_PRESENCE;
+
 import static com.android.server.nearby.NearbyService.TAG;
 
 import android.content.Context;
 import android.nearby.IScanListener;
 import android.nearby.NearbyDeviceParcelable;
+import android.nearby.PresenceScanFilter;
+import android.nearby.ScanFilter;
 import android.nearby.ScanRequest;
 import android.os.IBinder;
 import android.os.RemoteException;
@@ -29,10 +33,13 @@
 import com.android.internal.annotations.GuardedBy;
 import com.android.server.nearby.injector.Injector;
 import com.android.server.nearby.metrics.NearbyMetrics;
+import com.android.server.nearby.presence.PresenceDiscoveryResult;
 
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.Objects;
+import java.util.stream.Collectors;
 
 /**
  * Manages all aspects of discovery providers.
@@ -56,6 +63,16 @@
                     Log.w(TAG, "DiscoveryProviderManager cannot find the scan record.");
                     continue;
                 }
+                if (nearbyDevice.getScanType() == SCAN_TYPE_NEARBY_PRESENCE) {
+                    List<ScanFilter> presenceFilters =
+                            record.getScanRequest().getScanFilters().stream().filter(
+                                    scanFilter -> scanFilter.getType()
+                                            == SCAN_TYPE_NEARBY_PRESENCE).collect(
+                                    Collectors.toList());
+                    if (!presenceFilterMatches(nearbyDevice, presenceFilters)) {
+                        continue;
+                    }
+                }
                 try {
                     record.getScanListener().onDiscovered(
                             PrivacyFilter.filter(record.getScanRequest().getScanType(),
@@ -175,6 +192,22 @@
         mBleDiscoveryProvider.getController().setProviderScanMode(mScanMode);
     }
 
+    private static boolean presenceFilterMatches(NearbyDeviceParcelable device,
+            List<ScanFilter> scanFilters) {
+        if (scanFilters.isEmpty()) {
+            return true;
+        }
+        PresenceDiscoveryResult discoveryResult = PresenceDiscoveryResult.fromScanData(
+                device.getData(), device.getRssi());
+        for (ScanFilter scanFilter : scanFilters) {
+            PresenceScanFilter presenceScanFilter = (PresenceScanFilter) scanFilter;
+            if (discoveryResult.matches(presenceScanFilter)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
     private static class ScanListenerRecord {
 
         private final ScanRequest mScanRequest;
diff --git a/nearby/tests/unit/src/com/android/server/nearby/presence/PresenceDiscoveryResultTest.java b/nearby/tests/unit/src/com/android/server/nearby/presence/PresenceDiscoveryResultTest.java
new file mode 100644
index 0000000..dd94778
--- /dev/null
+++ b/nearby/tests/unit/src/com/android/server/nearby/presence/PresenceDiscoveryResultTest.java
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2022 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.nearby.presence;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.nearby.PresenceCredential;
+import android.nearby.PresenceDevice;
+import android.nearby.PresenceScanFilter;
+import android.nearby.PublicCredential;
+
+import androidx.test.filters.SdkSuppress;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import java.util.Arrays;
+
+/**
+ * Unit tests for {@link PresenceDiscoveryResult}.
+ */
+public class PresenceDiscoveryResultTest {
+    private static final int PRESENCE_ACTION = 123;
+    private static final int TX_POWER = -1;
+    private static final int RSSI = -41;
+    private static final byte[] SALT = new byte[]{12, 34};
+    private static final byte[] SECRET_ID = new byte[]{1, 2, 3, 4};
+    private static final byte[] AUTHENTICITY_KEY = new byte[]{12, 13, 14};
+
+    private PresenceDiscoveryResult.Builder mBuilder;
+    private PublicCredential mCredential;
+
+    @Before
+    public void setUp() {
+        mCredential =
+                new PublicCredential.Builder(SECRET_ID, AUTHENTICITY_KEY)
+                        .setIdentityType(PresenceCredential.IDENTITY_TYPE_PRIVATE)
+                        .build();
+        mBuilder = new PresenceDiscoveryResult.Builder()
+                .setPublicCredential(mCredential)
+                .setSalt(SALT)
+                .setTxPower(TX_POWER)
+                .setRssi(RSSI)
+                .addPresenceAction(PRESENCE_ACTION);
+    }
+
+    @Test
+    @SdkSuppress(minSdkVersion = 32, codeName = "T")
+    public void testToDevice() {
+        PresenceDiscoveryResult discoveryResult = mBuilder.build();
+        PresenceDevice presenceDevice = discoveryResult.toPresenceDevice();
+
+        assertThat(presenceDevice.getRssi()).isEqualTo(RSSI);
+        assertThat(Arrays.equals(presenceDevice.getSalt(), SALT)).isTrue();
+        assertThat(Arrays.equals(presenceDevice.getSecretId(), SECRET_ID)).isTrue();
+    }
+
+    @Test
+    @SdkSuppress(minSdkVersion = 32, codeName = "T")
+    public void testMatches() {
+        PresenceScanFilter scanFilter = new PresenceScanFilter.Builder()
+                .setMaxPathLoss(80)
+                .addPresenceAction(PRESENCE_ACTION)
+                .addCredential(mCredential)
+                .build();
+
+        PresenceDiscoveryResult discoveryResult = mBuilder.build();
+        assertThat(discoveryResult.matches(scanFilter)).isTrue();
+    }
+
+}