Extended the sample app's capabilities in order to be able to send a create_htlc operation

- The brainkey must be specified in code before trying this feature out.

sample/src/main/AndroidManifest.xml

@@ -14,10 +14,11 @@
         android:supportsRtl="true"
         android:theme="@style/AppTheme"
         tools:ignore="GoogleAppIndexingWarning">
+        <activity android:name=".HtlcActivity"></activity>
         <activity
             android:name=".BrainkeyActivity"
             android:label="@string/title_activity_brainkey"
-            android:theme="@style/AppTheme.NoActionBar"></activity>
+            android:theme="@style/AppTheme.NoActionBar" />
         <activity android:name=".SubscriptionActivity" />
         <activity android:name=".CallsActivity">
             <intent-filter>

sample/src/main/java/cy/agorise/labs/sample/CallsActivity.java

@@ -27,6 +27,7 @@ public class CallsActivity extends AppCompatActivity {
 
     private static final String RECONNECT_NODE = "reconnect_node";
     private static final String TEST_BRAINKEY_DERIVATION = "test_brainkey_derivation";
+    private static final String CREATE_HTLC = "create_htlc";
 
     @BindView(R.id.call_list)
     RecyclerView mRecyclerView;
@@ -83,7 +84,8 @@ public class CallsActivity extends AppCompatActivity {
             RPC.CALL_BROADCAST_TRANSACTION,
             RPC.CALL_GET_TRANSACTION,
             RECONNECT_NODE,
-            TEST_BRAINKEY_DERIVATION
+            TEST_BRAINKEY_DERIVATION,
+            CREATE_HTLC
         };
 
         @NonNull
@@ -108,7 +110,9 @@ public class CallsActivity extends AppCompatActivity {
                     intent = new Intent(CallsActivity.this, RemoveNodeActivity.class);
                 } else if (selectedCall.equals(TEST_BRAINKEY_DERIVATION)){
                     intent = new Intent(CallsActivity.this, BrainkeyActivity.class);
-                } else {
+                } else if (selectedCall.equals(CREATE_HTLC)){
+                    intent = new Intent(CallsActivity.this, HtlcActivity.class);
+                }else {
                     intent = new Intent(CallsActivity.this, PerformCallActivity.class);
                     intent.putExtra(Constants.KEY_SELECTED_CALL, selectedCall);
                 }

sample/src/main/java/cy/agorise/labs/sample/HtlcActivity.java

@@ -0,0 +1,137 @@
+package cy.agorise.labs.sample;
+
+import android.content.ComponentName;
+import android.os.Bundle;
+import android.os.IBinder;
+import android.util.Log;
+
+import com.google.common.primitives.UnsignedLong;
+
+import org.bitcoinj.core.ECKey;
+
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+import java.util.ArrayList;
+
+import cy.agorise.graphenej.Address;
+import cy.agorise.graphenej.Asset;
+import cy.agorise.graphenej.AssetAmount;
+import cy.agorise.graphenej.BaseOperation;
+import cy.agorise.graphenej.BlockData;
+import cy.agorise.graphenej.BrainKey;
+import cy.agorise.graphenej.HtlcHash;
+import cy.agorise.graphenej.HtlcHashType;
+import cy.agorise.graphenej.Transaction;
+import cy.agorise.graphenej.UserAccount;
+import cy.agorise.graphenej.Util;
+import cy.agorise.graphenej.api.ConnectionStatusUpdate;
+import cy.agorise.graphenej.api.android.RxBus;
+import cy.agorise.graphenej.api.calls.BroadcastTransaction;
+import cy.agorise.graphenej.api.calls.GetDynamicGlobalProperties;
+import cy.agorise.graphenej.models.DynamicGlobalProperties;
+import cy.agorise.graphenej.models.JsonRpcResponse;
+import cy.agorise.graphenej.operations.CreateHtlcOperation;
+import cy.agorise.labs.sample.fragments.CreateHtlcFragment;
+import io.reactivex.android.schedulers.AndroidSchedulers;
+import io.reactivex.disposables.Disposable;
+import io.reactivex.functions.Consumer;
+
+public class HtlcActivity extends ConnectedActivity implements CreateHtlcFragment.HtlcListener {
+    private String TAG = this.getClass().getName();
+    private final short PREIMAGE_LENGTH = 32;
+
+    private CreateHtlcOperation createHtlcOperation;
+    private Disposable mDisposable;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_htlc);
+    }
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+        mDisposable = RxBus.getBusInstance()
+            .asFlowable()
+            .observeOn(AndroidSchedulers.mainThread())
+            .subscribe(new Consumer<Object>() {
+
+                @Override
+                public void accept(Object message) throws Exception {
+                    if(message instanceof ConnectionStatusUpdate){
+                        // TODO: Update UI ?
+                    }else if(message instanceof JsonRpcResponse){
+                        handleJsonRpcResponse((JsonRpcResponse) message);
+                    }
+                }
+            });
+    }
+
+    @Override
+    protected void onPause() {
+        super.onPause();
+        if(!mDisposable.isDisposed())
+            mDisposable.dispose();
+
+    }
+
+    @Override
+    public void onHtlcProposal(String from, String to, Double amount, Long timelock) {
+        Log.d(TAG,"onHtlcProposal");
+        UserAccount sourceAccount = new UserAccount(from);
+        UserAccount destinationAccount = new UserAccount(to);
+        AssetAmount fee = new AssetAmount(UnsignedLong.valueOf("86726"), new Asset("1.3.0"));
+        AssetAmount operationAmount = new AssetAmount(UnsignedLong.valueOf(Double.valueOf(amount * 100000).longValue()), new Asset("1.3.0"));
+        SecureRandom secureRandom = new SecureRandom();
+        byte[] preimage = new byte[PREIMAGE_LENGTH];
+        secureRandom.nextBytes(preimage);
+        try {
+            byte[] hash = Util.htlcHash(preimage, HtlcHashType.RIPEMD160);
+            HtlcHash htlcHash = new HtlcHash(HtlcHashType.RIPEMD160, hash);
+            // Creating a HTLC operation, used later.
+            createHtlcOperation = new CreateHtlcOperation(fee, sourceAccount, destinationAccount, operationAmount, htlcHash, PREIMAGE_LENGTH, timelock.intValue());
+            // Requesting dynamic network parameters
+            long id = mNetworkService.sendMessage(new GetDynamicGlobalProperties(), GetDynamicGlobalProperties.REQUIRED_API);
+            Log.d(TAG,"sendMessage returned: " + id);
+        } catch (NoSuchAlgorithmException e) {
+            Log.e(TAG,"NoSuchAlgorithmException while trying to create HTLC operation. Msg: " + e.getMessage());
+        }
+    }
+
+    private void handleJsonRpcResponse(JsonRpcResponse jsonRpcResponse){
+        Log.d(TAG,"handleJsonRpcResponse");
+        if(jsonRpcResponse.error == null && jsonRpcResponse.result instanceof DynamicGlobalProperties){
+            DynamicGlobalProperties dynamicGlobalProperties = (DynamicGlobalProperties) jsonRpcResponse.result;
+            Transaction tx = buildHltcTransaction(dynamicGlobalProperties);
+            long id = mNetworkService.sendMessage(new BroadcastTransaction(tx), BroadcastTransaction.REQUIRED_API);
+            Log.d(TAG,"sendMessage returned: " + id);
+        }
+    }
+
+    private Transaction buildHltcTransaction(DynamicGlobalProperties dynamicProperties){
+        // Deriving private key
+        BrainKey brainKey = new BrainKey(">> Enter your own test Brainkey here <<", 0);
+        ECKey privKey = brainKey.getPrivateKey();
+        Address address = new Address(ECKey.fromPublicOnly(privKey.getPubKey()));
+
+        // Use the valid BlockData just obtained from the blockchain
+        long expirationTime = (dynamicProperties.time.getTime() / 1000) + Transaction.DEFAULT_EXPIRATION_TIME;
+        String headBlockId = dynamicProperties.head_block_id;
+        long headBlockNumber = dynamicProperties.head_block_number;
+        BlockData blockData = new BlockData(headBlockNumber, headBlockId, expirationTime);
+
+        // Using the HTLC create operaton just obtained before
+        ArrayList<BaseOperation> operations = new ArrayList<>();
+        operations.add(this.createHtlcOperation);
+
+        // Return a newly built transaction
+        return new Transaction(privKey, blockData, operations);
+    }
+
+    @Override
+    public void onServiceConnected(ComponentName componentName, IBinder iBinder) { }
+
+    @Override
+    public void onServiceDisconnected(ComponentName componentName) { }
+}

sample/src/main/java/cy/agorise/labs/sample/fragments/CreateHtlcFragment.java

@@ -0,0 +1,101 @@
+package cy.agorise.labs.sample.fragments;
+
+
+import android.content.Context;
+import android.os.Bundle;
+import android.support.design.widget.TextInputEditText;
+import android.support.v4.app.Fragment;
+import android.util.Log;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.Toast;
+
+import butterknife.BindView;
+import butterknife.ButterKnife;
+import butterknife.OnClick;
+import cy.agorise.labs.sample.R;
+
+/**
+ * A simple {@link Fragment} subclass.
+ */
+public class CreateHtlcFragment extends Fragment {
+    private final String TAG = this.getClass().getName();
+
+    @BindView(R.id.from)
+    TextInputEditText fromField;
+
+    @BindView(R.id.to)
+    TextInputEditText toField;
+
+    @BindView(R.id.amount)
+    TextInputEditText amountField;
+
+    @BindView(R.id.timelock)
+    TextInputEditText timelockField;
+
+    // Parent activity, which must implement the HtlcListener interface.
+    private HtlcListener mListener;
+
+    public CreateHtlcFragment() {
+        // Required empty public constructor
+    }
+
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+                             Bundle savedInstanceState) {
+        View view = inflater.inflate(R.layout.fragment_create_htlc, container, false);
+        ButterKnife.bind(this, view);
+        return view;
+    }
+
+    @OnClick(R.id.button_create)
+    public void onSendClicked(View v){
+        Log.d(TAG,"onSendClicked");
+        String from = fromField.getText().toString();
+        String to = toField.getText().toString();
+        Double amount = null;
+        Long timeLock = null;
+        try{
+            amount = Double.parseDouble(amountField.getText().toString());
+        }catch(NumberFormatException e){
+            amountField.setError("Invalid amount");
+        }
+        try{
+            timeLock = Long.parseLong(timelockField.getText().toString());
+        }catch(NumberFormatException e){
+            timelockField.setError("Invalid value");
+        }
+        Log.d(TAG,"amount: " + amount + ", timelock: " + timeLock);
+        if(amount != null && timeLock != null){
+            Toast.makeText(getContext(), "Should be sending message up", Toast.LENGTH_SHORT).show();
+            mListener.onHtlcProposal(from, to, amount, timeLock);
+        }
+    }
+
+    @Override
+    public void onAttach(Context context) {
+        super.onAttach(context);
+        if(context instanceof HtlcListener){
+            mListener = (HtlcListener) context;
+        }else{
+            throw new ClassCastException(context.toString() + " must implement the HtlcListener interface!");
+        }
+    }
+
+    /**
+     * Interface to be implemented by the parent activity.
+     */
+    public interface HtlcListener {
+        /**
+         * Method used to notify the parent activity of the request to create an HTLC with the following parameters.
+         *
+         * @param from Source account id.
+         * @param to Destination account id.
+         * @param amount The amount of BTS to propose the HTLC.
+         * @param timelock The timelock in seconds.
+         */
+        void onHtlcProposal(String from, String to, Double amount, Long timelock);
+    }
+}

sample/src/main/java/cy/agorise/labs/sample/fragments/PrintResponseFragment.java

@@ -0,0 +1,30 @@
+package cy.agorise.labs.sample.fragments;
+
+
+import android.os.Bundle;
+import android.support.v4.app.Fragment;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import cy.agorise.labs.sample.R;
+
+/**
+ * A simple {@link Fragment} subclass.
+ */
+public class PrintResponseFragment extends Fragment {
+
+
+    public PrintResponseFragment() {
+        // Required empty public constructor
+    }
+
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+                             Bundle savedInstanceState) {
+        // Inflate the layout for this fragment
+        return inflater.inflate(R.layout.fragment_print_response, container, false);
+    }
+
+}

sample/src/main/res/layout/activity_htlc.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical"
+    tools:context=".HtlcActivity">
+    <fragment android:name="cy.agorise.labs.sample.fragments.PrintResponseFragment"
+        android:id="@+id/fragment_print_response"
+        android:layout_weight="0.4"
+        android:layout_height="0dp"
+        android:layout_width="match_parent"/>
+    <fragment android:name="cy.agorise.labs.sample.fragments.CreateHtlcFragment"
+        android:id="@+id/fragment_htlc_parameters"
+        android:layout_weight="0.6"
+        android:layout_height="0dp"
+        android:layout_width="match_parent"/>
+</LinearLayout>

sample/src/main/res/layout/fragment_create_htlc.xml

@@ -0,0 +1,71 @@
+<?xml version="1.0" encoding="utf-8"?>
+<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:layout_margin="16dp"
+    tools:context=".fragments.CreateHtlcFragment">
+    <android.support.design.widget.TextInputLayout
+        android:id="@+id/container_from"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:hint="@string/hint_from"
+        app:layout_constraintBottom_toTopOf="@+id/container_to"
+        app:layout_constraintTop_toTopOf="parent">
+
+        <android.support.design.widget.TextInputEditText
+            android:id="@+id/from"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:text="1.2.1029856" />
+    </android.support.design.widget.TextInputLayout>
+    <android.support.design.widget.TextInputLayout
+        android:id="@+id/container_to"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:hint="@string/hint_to"
+        app:layout_constraintBottom_toTopOf="@+id/container_amount"
+        app:layout_constraintTop_toBottomOf="@id/container_from">
+
+        <android.support.design.widget.TextInputEditText
+            android:id="@+id/to"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:text="1.2.153769" />
+    </android.support.design.widget.TextInputLayout>
+    <android.support.design.widget.TextInputLayout
+        android:id="@+id/container_amount"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:hint="@string/hint_amount"
+        app:layout_constraintBottom_toTopOf="@+id/container_timelock"
+        app:layout_constraintTop_toBottomOf="@+id/container_to">
+        <android.support.design.widget.TextInputEditText
+            android:id="@+id/amount"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:inputType="numberDecimal"
+            android:singleLine="true"
+            android:nextFocusDown="@+id/timelock"/>
+    </android.support.design.widget.TextInputLayout>
+    <android.support.design.widget.TextInputLayout
+        android:id="@+id/container_timelock"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:hint="@string/hint_timelock"
+        app:layout_constraintBottom_toTopOf="@+id/button_create"
+        app:layout_constraintTop_toBottomOf="@id/container_amount">
+        <android.support.design.widget.TextInputEditText
+            android:id="@+id/timelock"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:inputType="number"/>
+    </android.support.design.widget.TextInputLayout>
+    <Button
+        android:id="@+id/button_create"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="@string/action_send"
+        app:layout_constraintBottom_toBottomOf="parent"/>
+</android.support.constraint.ConstraintLayout>

sample/src/main/res/layout/fragment_print_response.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".fragments.PrintResponseFragment">
+    <TextView
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"/>
+</FrameLayout>

sample/src/main/res/values/strings.xml

@@ -70,4 +70,10 @@
     <string name="hint_brainkey">Brainkey</string>
     <string name="hint_pubkey">Desired public key / address</string>
     <string name="button_generate">Generate public key</string>
+
+    <!-- CreateHtlcFragment strings -->
+    <string name="hint_from">From account</string>
+    <string name="hint_to">To account</string>
+    <string name="hint_amount">Amount</string>
+    <string name="hint_timelock">Time to lock (in seconds)</string>
 </resources>