Add locally discovered devices to the "add device" dialog (fixes #305) (#306)

* ENABLE_TEST_DATA

* http/GetRequest: Add URI_SYSTEM_DISCOVERY

* Add model/DiscoveredDevice

* Add RestApi#getDiscoveredDevices (fixes #305)

* Add DeviceActivity#asyncQueryDiscoveredDevices in onServiceConnected (fixes #305)

* Add strings

* Add layout: item_discovered_device_form

* Add discoveredDevicesTitle, discoveredDevicesContainer to "add device" dialog (fixes #305)

* Revert "ENABLE_TEST_DATA"

This reverts commit b2efe73b9b4f7e9d4db8cc50cb48a5422f78c084.

* Fix lint error

* Updated de translation

app/src/main/java/com/nutomic/syncthingandroid/activities/DeviceActivity.java

@@ -14,11 +14,15 @@ import android.text.Editable;
 import android.text.TextUtils;
 import android.text.TextWatcher;
 import android.util.Log;
+import android.util.TypedValue;
+import android.view.LayoutInflater;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
+import android.view.ViewGroup;
 import android.widget.CompoundButton;
 import android.widget.EditText;
+import android.widget.LinearLayout;
 import android.widget.TextView;
 import android.widget.Toast;
 
@@ -29,6 +33,7 @@ import com.google.zxing.integration.android.IntentResult;
 import com.nutomic.syncthingandroid.R;
 import com.nutomic.syncthingandroid.model.Connections;
 import com.nutomic.syncthingandroid.model.Device;
+import com.nutomic.syncthingandroid.model.DiscoveredDevice;
 import com.nutomic.syncthingandroid.service.Constants;
 import com.nutomic.syncthingandroid.service.RestApi;
 import com.nutomic.syncthingandroid.service.SyncthingService;
@@ -42,12 +47,19 @@ import com.nutomic.syncthingandroid.util.Util;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 
 import javax.inject.Inject;
 
+import static android.support.v4.view.MarginLayoutParamsCompat.setMarginEnd;
+import static android.support.v4.view.MarginLayoutParamsCompat.setMarginStart;
 import static android.text.TextUtils.isEmpty;
+import static android.util.TypedValue.COMPLEX_UNIT_DIP;
 import static android.view.View.VISIBLE;
 import static android.view.WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN;
+import static android.view.Gravity.CENTER_VERTICAL;
+import static android.view.ViewGroup.LayoutParams.WRAP_CONTENT;
+
 import static com.nutomic.syncthingandroid.util.Compression.METADATA;
 
 /**
@@ -75,6 +87,8 @@ public class DeviceActivity extends SyncthingActivity {
 
     private Device mDevice;
     private EditText mEditDeviceId;
+    private TextView mDiscoveredDevicesTitle;
+    private ViewGroup mDiscoveredDevicesContainer;
     private View mShowDeviceIdContainer;
     private EditText mShowDeviceId;
     private View mQrButton;
@@ -182,6 +196,8 @@ public class DeviceActivity extends SyncthingActivity {
         setTitle(mIsCreateMode ? R.string.add_device : R.string.edit_device);
 
         mEditDeviceId = findViewById(R.id.editDeviceId);
+        mDiscoveredDevicesTitle = findViewById(R.id.discoveredDevicesTitle);
+        mDiscoveredDevicesContainer = findViewById(R.id.discoveredDevicesContainer);
         mShowDeviceIdContainer = findViewById(R.id.showDeviceIdContainer);
         mShowDeviceId = findViewById(R.id.showDeviceId);
         mQrButton = findViewById(R.id.qrButton);
@@ -276,6 +292,9 @@ public class DeviceActivity extends SyncthingActivity {
         RestApi restApi = syncthingService.getApi();
         if (restApi != null) {
             restApi.getConnections(this::onReceiveConnections);
+            if (mIsCreateMode) {
+                asyncQueryDiscoveredDevices(restApi);
+            }
         }
     }
 
@@ -615,4 +634,83 @@ public class DeviceActivity extends SyncthingActivity {
                 .create();
         mDiscardDialog.show();
     }
+
+    /**
+     * Perform asynchronous query via REST to retrieve locally discovered devices.
+     * Precondition:
+     *      restApi != null
+     *      mIsCreateMode == true
+     */
+    private void asyncQueryDiscoveredDevices(RestApi restApi) {
+        if (!restApi.isConfigLoaded()) {
+            return;
+        }
+        restApi.getDiscoveredDevices(this::onReceiveDiscoveredDevices);
+    }
+
+    /**
+     * Callback after {@link asyncQueryDiscoveredDevices}.
+     * Precondition:
+     *      mIsCreateMode == true
+     */
+    private void onReceiveDiscoveredDevices(Map<String, DiscoveredDevice> discoveredDevices) {
+        if (discoveredDevices == null) {
+            Log.e(TAG, "onReceiveDiscoveredDevices: discoveredDevices == null");
+            return;
+        }
+
+        mDiscoveredDevicesContainer.removeAllViews();
+        if (discoveredDevices.size() == 0) {
+            // No discovered devices.
+            int height = (int) TypedValue.applyDimension(COMPLEX_UNIT_DIP, 48, getResources().getDisplayMetrics());
+            LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(WRAP_CONTENT, height);
+            int dividerInset = getResources().getDimensionPixelOffset(R.dimen.material_divider_inset);
+            int contentInset = getResources().getDimensionPixelOffset(R.dimen.abc_action_bar_content_inset_material);
+            setMarginStart(params, dividerInset);
+            setMarginEnd(params, contentInset);
+            TextView emptyView = new TextView(mDiscoveredDevicesContainer.getContext());
+            emptyView.setGravity(CENTER_VERTICAL);
+            emptyView.setText(R.string.discovered_device_list_empty);
+            mDiscoveredDevicesContainer.addView(emptyView, params);
+            return;
+        }
+
+        for (String deviceId : discoveredDevices.keySet()) {
+            if (deviceId != null) {
+                // Get device address.
+                String readableAddresses = "";
+                DiscoveredDevice discoveredDevice = discoveredDevices.get(deviceId);
+                if (discoveredDevice != null && discoveredDevice.addresses != null) {
+                    readableAddresses = TextUtils.join(", ", discoveredDevice.addresses);
+                    // Log.v(TAG, "onReceiveDiscoveredDevices: deviceID = '" + deviceId + "' has addresses '" + readableAddresses + "'");
+                }
+                String caption = deviceId + (TextUtils.isEmpty(readableAddresses) ? "" : " (" + readableAddresses + ")");
+                LayoutInflater inflater = getLayoutInflater();
+                inflater.inflate(R.layout.item_discovered_device_form, mDiscoveredDevicesContainer);
+                TextView deviceIdView = (TextView) mDiscoveredDevicesContainer.getChildAt(mDiscoveredDevicesContainer.getChildCount()-1);
+                deviceIdView.setOnClickListener(null);
+                deviceIdView.setText(caption);
+                deviceIdView.setTag(deviceId);
+                deviceIdView.setOnClickListener(v -> onDeviceIdViewClick(v));
+            }
+        }
+
+        /**
+         * If "mEditDeviceId" already contains content, don't show local discovery results.
+         * This also suppresses the results being shown a second time after the user chose a
+         * deviceId from the list and rotated the screen.
+         */
+        mDiscoveredDevicesTitle.setVisibility(TextUtils.isEmpty(mEditDeviceId.getText()) ? View.VISIBLE : View.GONE);
+        mDiscoveredDevicesContainer.setVisibility(TextUtils.isEmpty(mEditDeviceId.getText()) ? View.VISIBLE : View.GONE);
+    }
+
+    /**
+     * Copies the deviceId from TextView to "device_id" EditText.
+     * Hides the "mDiscoveredDevicesContainer" view afterwards.
+     */
+    private void onDeviceIdViewClick(View view) {
+        mEditDeviceId.setText((String) view.getTag());
+        mDiscoveredDevicesTitle.setVisibility(View.GONE);
+        mDiscoveredDevicesContainer.setVisibility(View.GONE);
+    }
 }

app/src/main/java/com/nutomic/syncthingandroid/http/GetRequest.java

@@ -18,6 +18,7 @@ public class GetRequest extends ApiRequest {
 
     public static final String URI_CONFIG           = "/rest/system/config";
     public static final String URI_DEBUG            = "/rest/system/debug";
+    public static final String URI_SYSTEM_DISCOVERY = "/rest/system/discovery";
     public static final String URI_VERSION          = "/rest/system/version";
     public static final String URI_SYSTEM_STATUS    = "/rest/system/status";
     public static final String URI_CONNECTIONS      = "/rest/system/connections";

app/src/main/java/com/nutomic/syncthingandroid/model/DiscoveredDevice.java

@@ -0,0 +1,22 @@
+package com.nutomic.syncthingandroid.model;
+
+import java.util.Map;
+
+/**
+ * This receives the deserialization result of the URI_SYSTEM_DISCOVERY query.
+ *
+ * JSON result example
+ *    {
+ *          "2MY7NNQ-IRBZIFP-B2V574Y-AX6FNIP-55VGH5H-GUD3RFV-K2RXX6P-XXXXXX":
+ *          {
+ *              "addresses":
+ *                  [
+ *                      "tcp4://192.168.178.10:40001"
+ *                  ]
+ *          }
+ *    }
+ *
+ */
+public class DiscoveredDevice {
+    public String[] addresses;
+}

app/src/main/java/com/nutomic/syncthingandroid/service/RestApi.java

@@ -26,6 +26,7 @@ import com.nutomic.syncthingandroid.model.Completion;
 import com.nutomic.syncthingandroid.model.CompletionInfo;
 import com.nutomic.syncthingandroid.model.Connections;
 import com.nutomic.syncthingandroid.model.Device;
+import com.nutomic.syncthingandroid.model.DiscoveredDevice;
 import com.nutomic.syncthingandroid.model.DiskEvent;
 import com.nutomic.syncthingandroid.model.Event;
 import com.nutomic.syncthingandroid.model.Folder;
@@ -618,6 +619,23 @@ public class RestApi {
         }
     }
 
+    /**
+     * Requests locally discovered devices.
+     */
+    public void getDiscoveredDevices(OnResultListener1<Map<String, DiscoveredDevice>> listener) {
+        new GetRequest(mContext, mUrl, GetRequest.URI_SYSTEM_DISCOVERY, mApiKey,
+                null, result -> {
+            Map<String, DiscoveredDevice> discoveredDevices = mGson.fromJson(result, new TypeToken<Map<String, DiscoveredDevice>>(){}.getType());
+            if (ENABLE_TEST_DATA) {
+                DiscoveredDevice fakeDiscoveredDevice = new DiscoveredDevice();
+                fakeDiscoveredDevice.addresses = new String[]{"tcp4://192.168.178.10:40004"};
+                discoveredDevices.put("ZOK75WR-W3XWWUZ-NNLXV7V-DUYKVWA-SSPD7OH-3QYOZBY-SBH3N2Y-IAVJ4QH", fakeDiscoveredDevice);
+                discoveredDevices.put("ZPUZOWC-SUCJILE-ITNLBLL-MHBWJG5-46QM47Y-CDTQT3M-IA4RSJV-7BYA7QA", fakeDiscoveredDevice);
+            }
+            listener.onResult(discoveredDevices);
+        });
+    }
+
     /**
      * Requests ignore list for given folder.
      */

app/src/main/res/layout/fragment_device.xml

@@ -56,6 +56,26 @@
 
             </LinearLayout>
 
+            <TextView
+                style="@style/Widget.Syncthing.TextView.Label.Details"
+                android:id="@+id/discoveredDevicesTitle"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:drawableLeft="@drawable/ic_device_hub_black_24dp_active"
+                android:drawableStart="@drawable/ic_device_hub_black_24dp_active"
+                android:focusable="false"
+                android:text="@string/discovered_devices_title"
+                android:visibility="gone" />
+
+            <LinearLayout
+                android:id="@+id/discoveredDevicesContainer"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:orientation="vertical"
+                android:focusable="false"
+                android:visibility="gone">
+            </LinearLayout>
+
             <!-- Option 2: Show or copy device ID -->
             <LinearLayout
                 android:id="@+id/showDeviceIdContainer"

app/src/main/res/layout/item_discovered_device_form.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<TextView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/device_button"
+    style="@style/Widget.Syncthing.TextView.Label.Details.DeviceList"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_marginLeft="@dimen/material_divider_inset"
+    android:layout_marginStart="@dimen/material_divider_inset"
+    android:layout_marginEnd="@dimen/abc_action_bar_content_inset_material"
+    android:layout_marginRight="@dimen/abc_action_bar_content_inset_material"
+    android:clickable="true"
+    android:drawableEnd="@drawable/ic_content_copy_black_24dp"
+    android:drawableRight="@drawable/ic_content_copy_black_24dp"
+    android:focusable="true"
+    android:textAppearance="@style/TextAppearance.AppCompat.Caption"
+    tools:ignore="RtlHardcoded,RtlSymmetry"
+    tools:text="ASD1ASD-ASD1ASD-ASD1ASD-ASD1ASD-ASD1ASD-ASD1ASD-ASD1ASD-ASD1ASD" />

app/src/main/res/values-de/strings.xml

@@ -257,6 +257,12 @@ Bitte melden Sie auftretende Probleme via GitHub.</string>
     <!-- Setting title -->
     <string name="device_id">Geräte-ID</string>
 
+    <!-- Status title -->
+    <string name="discovered_devices_title">Gefundene Geräte - Tippe zur Auswahl</string>
+
+    <!-- Status text -->
+    <string name="discovered_device_list_empty">Die lokale Geräteerkennung hat im lokalen Netzwerk keine Geräte gefunden.</string>
+
     <!-- Setting title -->
     <string name="name">Name</string>
 

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

@@ -260,6 +260,12 @@ Please report any problems you encounter via Github.</string>
     <!-- Setting title -->
     <string name="device_id">Device ID</string>
 
+    <!-- Status title -->
+    <string name="discovered_devices_title">Discovered devices - Tap to select</string>
+
+    <!-- Status text -->
+    <string name="discovered_device_list_empty">Local discovery didn\'t find any devices on the local network.</string>
+
     <!-- Setting title -->
     <string name="name">Name</string>