Add basic Bluetooth pairing and A2DP connection features. (#54)

* Add support for pairing/unpairing a device.
* Add support for connecting with A2DP profile.
* Reorganize Bluetooth related snippets for future expansion of profile support.
* Use Bundle instead of JSONObject for BluetoothDevice serialization.

4 files changed, 236 insertions, 15 deletions

diff --git a/src/main/java/com/google/android/mobly/snippet/bundled/BluetoothAdapterSnippet.java b/src/main/java/com/google/android/mobly/snippet/bundled/bluetooth/BluetoothAdapterSnippet.java
index 0f4d3e6..5971517 100644
--- a/src/main/java/com/google/android/mobly/snippet/bundled/BluetoothAdapterSnippet.java
+++ b/src/main/java/com/google/android/mobly/snippet/bundled/bluetooth/BluetoothAdapterSnippet.java
@@ -14,7 +14,7 @@
  * the License.
  */
 
-package com.google.android.mobly.snippet.bundled;
+package com.google.android.mobly.snippet.bundled.bluetooth;
 
 import android.bluetooth.BluetoothAdapter;
 import android.bluetooth.BluetoothDevice;
@@ -31,7 +31,9 @@ import com.google.android.mobly.snippet.bundled.utils.Utils;
 import com.google.android.mobly.snippet.rpc.Rpc;
 import com.google.android.mobly.snippet.rpc.RpcMinSdk;
 import java.util.ArrayList;
-import org.json.JSONArray;
+import java.util.List;
+import java.util.NoSuchElementException;
+import java.util.concurrent.ConcurrentHashMap;
 import org.json.JSONException;
 
 /** Snippet class exposing Android APIs in BluetoothAdapter. */
@@ -45,14 +47,44 @@ public class BluetoothAdapterSnippet implements Snippet {
     }
 
     private final Context mContext;
-    private final BluetoothAdapter mBluetoothAdapter;
+    private static final BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
     private final JsonSerializer mJsonSerializer = new JsonSerializer();
-    private final ArrayList<BluetoothDevice> mDiscoveryResults = new ArrayList<>();
+    private static final ConcurrentHashMap<String, BluetoothDevice> mDiscoveryResults =
+            new ConcurrentHashMap<>();
     private volatile boolean mIsScanResultAvailable = false;
 
     public BluetoothAdapterSnippet() {
         mContext = InstrumentationRegistry.getContext();
-        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
+    }
+
+    /**
+     * Gets a {@link BluetoothDevice} that has either been paired or discovered.
+     *
+     * @param deviceAddress
+     * @return
+     */
+    public static BluetoothDevice getKnownDeviceByAddress(String deviceAddress) {
+        BluetoothDevice pairedDevice = getPairedDeviceByAddress(deviceAddress);
+        if (pairedDevice != null) {
+            return pairedDevice;
+        }
+        BluetoothDevice discoveredDevice = mDiscoveryResults.get(deviceAddress);
+        if (discoveredDevice != null) {
+            return discoveredDevice;
+        }
+        throw new NoSuchElementException(
+                "No device with address "
+                        + deviceAddress
+                        + " is paired or has been discovered. Cannot proceed.");
+    }
+
+    private static BluetoothDevice getPairedDeviceByAddress(String deviceAddress) {
+        for (BluetoothDevice device : mBluetoothAdapter.getBondedDevices()) {
+            if (device.getAddress().equalsIgnoreCase(deviceAddress)) {
+                return device;
+            }
+        }
+        return null;
     }
 
     @Rpc(description = "Enable bluetooth with a 30s timeout.")
@@ -84,12 +116,8 @@ public class BluetoothAdapterSnippet implements Snippet {
         description =
                 "Get bluetooth discovery results, which is a list of serialized BluetoothDevice objects."
     )
-    public JSONArray btGetCachedScanResults() throws JSONException {
-        JSONArray results = new JSONArray();
-        for (BluetoothDevice result : mDiscoveryResults) {
-            results.put(mJsonSerializer.toJson(result));
-        }
-        return results;
+    public ArrayList<Bundle> btGetCachedScanResults() {
+        return mJsonSerializer.serializeBluetoothDeviceList(mDiscoveryResults.values());
     }
 
     @Rpc(description = "Set the friendly Bluetooth name of the local Bluetooth adapter.")
@@ -119,8 +147,8 @@ public class BluetoothAdapterSnippet implements Snippet {
                 "Start discovery, wait for discovery to complete, and return results, which is a list of "
                         + "serialized BluetoothDevice objects."
     )
-    public JSONArray btDiscoverAndGetResults()
-            throws InterruptedException, JSONException, BluetoothAdapterSnippetException {
+    public List<Bundle> btDiscoverAndGetResults()
+            throws InterruptedException, BluetoothAdapterSnippetException {
         IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
         filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
         if (mBluetoothAdapter.isDiscovering()) {
@@ -174,7 +202,7 @@ public class BluetoothAdapterSnippet implements Snippet {
     }
 
     @Rpc(description = "Get the list of paired bluetooth devices.")
-    public ArrayList<Bundle> btGetPairedDevices()
+    public List<Bundle> btGetPairedDevices()
             throws BluetoothAdapterSnippetException, InterruptedException, JSONException {
         ArrayList<Bundle> pairedDevices = new ArrayList<>();
         for (BluetoothDevice device : mBluetoothAdapter.getBondedDevices()) {
@@ -183,6 +211,46 @@ public class BluetoothAdapterSnippet implements Snippet {
         return pairedDevices;
     }
 
+    @Rpc(description = "Pair with a bluetooth device.")
+    public void btPairDevice(String deviceAddress) throws Throwable {
+        BluetoothDevice device = mDiscoveryResults.get(deviceAddress);
+        if (device == null) {
+            throw new NoSuchElementException(
+                    "No device with address "
+                            + deviceAddress
+                            + " has been discovered. Cannot proceed.");
+        }
+        mContext.registerReceiver(
+                new PairingBroadcastReceiver(mContext), PairingBroadcastReceiver.filter);
+        if (!(boolean) Utils.invokeByReflection(device, "createBond")) {
+            throw new BluetoothAdapterSnippetException(
+                    "Failed to initiate the pairing process to device: " + deviceAddress);
+        }
+        if (!Utils.waitUntil(() -> device.getBondState() == BluetoothDevice.BOND_BONDED, 120)) {
+            throw new BluetoothAdapterSnippetException(
+                    "Failed to pair with device " + deviceAddress + " after 2min.");
+        }
+    }
+
+    @Rpc(description = "Un-pair a bluetooth device.")
+    public void btUnpairDevice(String deviceAddress) throws Throwable {
+        for (BluetoothDevice device : mBluetoothAdapter.getBondedDevices()) {
+            if (device.getAddress().equalsIgnoreCase(deviceAddress)) {
+                if (!(boolean) Utils.invokeByReflection(device, "removeBond")) {
+                    throw new BluetoothAdapterSnippetException(
+                            "Failed to initiate the un-pairing process for device: "
+                                    + deviceAddress);
+                }
+                if (!Utils.waitUntil(
+                        () -> device.getBondState() == BluetoothDevice.BOND_NONE, 30)) {
+                    throw new BluetoothAdapterSnippetException(
+                            "Failed to un-pair device " + deviceAddress + " after 30s.");
+                }
+            }
+        }
+        throw new NoSuchElementException("No device wih address " + deviceAddress + " is paired.");
+    }
+
     /**
      * Enable Bluetooth HCI snoop log collection.
      *
@@ -223,7 +291,7 @@ public class BluetoothAdapterSnippet implements Snippet {
             } else if (BluetoothDevice.ACTION_FOUND.equals(action)) {
                 BluetoothDevice device =
                         (BluetoothDevice) intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
-                mDiscoveryResults.add(device);
+                mDiscoveryResults.put(device.getAddress(), device);
             }
         }
     }
diff --git a/src/main/java/com/google/android/mobly/snippet/bundled/bluetooth/PairingBroadcastReceiver.java b/src/main/java/com/google/android/mobly/snippet/bundled/bluetooth/PairingBroadcastReceiver.java
new file mode 100644
index 0000000..0cfd362
--- /dev/null
+++ b/src/main/java/com/google/android/mobly/snippet/bundled/bluetooth/PairingBroadcastReceiver.java
@@ -0,0 +1,30 @@
+package com.google.android.mobly.snippet.bundled.bluetooth;
+
+import android.annotation.TargetApi;
+import android.bluetooth.BluetoothDevice;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.Build;
+import com.google.android.mobly.snippet.util.Log;
+
+@TargetApi(Build.VERSION_CODES.KITKAT)
+public class PairingBroadcastReceiver extends BroadcastReceiver {
+    private final Context mContext;
+    public static IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_PAIRING_REQUEST);
+
+    public PairingBroadcastReceiver(Context context) {
+        mContext = context;
+    }
+
+    public void onReceive(Context context, Intent intent) {
+        String action = intent.getAction();
+        if (action.equals(BluetoothDevice.ACTION_PAIRING_REQUEST)) {
+            BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
+            Log.d("Confirming pairing with device: " + device.getAddress());
+            device.setPairingConfirmation(true);
+            mContext.unregisterReceiver(this);
+        }
+    }
+}
diff --git a/src/main/java/com/google/android/mobly/snippet/bundled/bluetooth/profiles/BluetoothA2dpSnippet.java b/src/main/java/com/google/android/mobly/snippet/bundled/bluetooth/profiles/BluetoothA2dpSnippet.java
new file mode 100644
index 0000000..b218723
--- /dev/null
+++ b/src/main/java/com/google/android/mobly/snippet/bundled/bluetooth/profiles/BluetoothA2dpSnippet.java
@@ -0,0 +1,113 @@
+package com.google.android.mobly.snippet.bundled.bluetooth.profiles;
+
+import android.annotation.TargetApi;
+import android.bluetooth.BluetoothA2dp;
+import android.bluetooth.BluetoothAdapter;
+import android.bluetooth.BluetoothDevice;
+import android.bluetooth.BluetoothProfile;
+import android.content.Context;
+import android.content.IntentFilter;
+import android.os.Build;
+import android.os.Bundle;
+import android.support.test.InstrumentationRegistry;
+import com.google.android.mobly.snippet.Snippet;
+import com.google.android.mobly.snippet.bundled.bluetooth.BluetoothAdapterSnippet;
+import com.google.android.mobly.snippet.bundled.bluetooth.PairingBroadcastReceiver;
+import com.google.android.mobly.snippet.bundled.utils.JsonSerializer;
+import com.google.android.mobly.snippet.bundled.utils.Utils;
+import com.google.android.mobly.snippet.rpc.Rpc;
+import com.google.android.mobly.snippet.rpc.RpcMinSdk;
+import java.util.ArrayList;
+
+public class BluetoothA2dpSnippet implements Snippet {
+    private static class BluetoothA2dpSnippetException extends Exception {
+        private static final long serialVersionUID = 1;
+
+        BluetoothA2dpSnippetException(String msg) {
+            super(msg);
+        }
+    }
+
+    private Context mContext;
+    private static boolean sIsA2dpProfileReady = false;
+    private static BluetoothA2dp sA2dpProfile;
+    private final JsonSerializer mJsonSerializer = new JsonSerializer();
+
+    public BluetoothA2dpSnippet() {
+        mContext = InstrumentationRegistry.getContext();
+        BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
+        bluetoothAdapter.getProfileProxy(
+                mContext, new A2dpServiceListener(), BluetoothProfile.A2DP);
+        Utils.waitUntil(() -> sIsA2dpProfileReady, 60);
+    }
+
+    private static class A2dpServiceListener implements BluetoothProfile.ServiceListener {
+        public void onServiceConnected(int var1, BluetoothProfile profile) {
+            sA2dpProfile = (BluetoothA2dp) profile;
+            sIsA2dpProfileReady = true;
+        }
+
+        public void onServiceDisconnected(int var1) {
+            sIsA2dpProfileReady = false;
+        }
+    }
+
+    @TargetApi(Build.VERSION_CODES.KITKAT)
+    @RpcMinSdk(Build.VERSION_CODES.KITKAT)
+    @Rpc(
+        description =
+                "Connects to a paired or discovered device with A2DP profile."
+                        + "If a device has been discovered but not paired, this will pair it."
+    )
+    public void btA2dpConnect(String deviceAddress) throws Throwable {
+        BluetoothDevice device = BluetoothAdapterSnippet.getKnownDeviceByAddress(deviceAddress);
+        IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_PAIRING_REQUEST);
+        mContext.registerReceiver(new PairingBroadcastReceiver(mContext), filter);
+        Utils.invokeByReflection(sA2dpProfile, "connect", device);
+        if (!Utils.waitUntil(
+                () -> sA2dpProfile.getConnectionState(device) == BluetoothA2dp.STATE_CONNECTED,
+                120)) {
+            throw new BluetoothA2dpSnippetException(
+                    "Failed to connect to device "
+                            + device.getName()
+                            + "|"
+                            + device.getAddress()
+                            + " with A2DP profile within 2min.");
+        }
+    }
+
+    @Rpc(description = "Disconnects a device from A2DP profile.")
+    public void btA2dpDisconnect(String deviceAddress) throws Throwable {
+        BluetoothDevice device = getConnectedBluetoothDevice(deviceAddress);
+        Utils.invokeByReflection(sA2dpProfile, "disconnect", device);
+        if (!Utils.waitUntil(
+                () -> sA2dpProfile.getConnectionState(device) == BluetoothA2dp.STATE_DISCONNECTED,
+                120)) {
+            throw new BluetoothA2dpSnippetException(
+                    "Failed to disconnect device "
+                            + device.getName()
+                            + "|"
+                            + device.getAddress()
+                            + " from A2DP profile within 2min.");
+        }
+    }
+
+    @Rpc(description = "Gets all the devices currently connected via A2DP profile.")
+    public ArrayList<Bundle> btA2dpGetConnectedDevices() {
+        return mJsonSerializer.serializeBluetoothDeviceList(sA2dpProfile.getConnectedDevices());
+    }
+
+    private BluetoothDevice getConnectedBluetoothDevice(String deviceAddress)
+            throws BluetoothA2dpSnippetException {
+        for (BluetoothDevice device : sA2dpProfile.getConnectedDevices()) {
+            if (device.getAddress().equalsIgnoreCase(deviceAddress)) {
+                return device;
+            }
+        }
+        throw new BluetoothA2dpSnippetException(
+                "No device with address " + deviceAddress + " is connected via A2DP.");
+    }
+
+    @Override
+    public void shutdown() {}
+}
diff --git a/src/main/java/com/google/android/mobly/snippet/bundled/utils/JsonSerializer.java b/src/main/java/com/google/android/mobly/snippet/bundled/utils/JsonSerializer.java
index c555b92..7e5ca5b 100644
--- a/src/main/java/com/google/android/mobly/snippet/bundled/utils/JsonSerializer.java
+++ b/src/main/java/com/google/android/mobly/snippet/bundled/utils/JsonSerializer.java
@@ -33,6 +33,7 @@ import java.lang.reflect.Modifier;
 import java.net.InetAddress;
 import java.net.UnknownHostException;
 import java.util.ArrayList;
+import java.util.Collection;
 import org.json.JSONException;
 import org.json.JSONObject;
 
@@ -148,6 +149,15 @@ public class JsonSerializer {
         return result;
     }
 
+    public ArrayList<Bundle> serializeBluetoothDeviceList(
+            Collection<BluetoothDevice> bluetoothDevices) {
+        ArrayList<Bundle> results = new ArrayList<>();
+        for (BluetoothDevice device : bluetoothDevices) {
+            results.add(serializeBluetoothDevice(device));
+        }
+        return results;
+    }
+
     @TargetApi(Build.VERSION_CODES.LOLLIPOP)
     public Bundle serializeBleScanResult(android.bluetooth.le.ScanResult scanResult) {
         Bundle result = new Bundle();