Avoid the same node being added multiple times (fixes #65).

When trying to add a node that already exists, the existing node is edited
instead.

src/main/java/com/nutomic/syncthingandroid/gui/FolderPickerActivity.java

@@ -11,13 +11,11 @@ import android.os.Bundle;
 import android.os.Environment;
 import android.os.IBinder;
 import android.support.v7.app.ActionBarActivity;
-import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewGroup;
-import android.view.WindowManager;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.AdapterView;
 import android.widget.ArrayAdapter;
@@ -31,9 +29,7 @@ import com.nutomic.syncthingandroid.syncthing.SyncthingServiceBinder;
 
 import java.io.File;
 import java.io.FileFilter;
-import java.io.IOException;
 import java.util.Arrays;
-import java.util.Stack;
 
 /**
  * Activity that allows selecting a directory in the local file system.

src/main/java/com/nutomic/syncthingandroid/gui/LocalNodeInfoFragment.java

@@ -1,10 +1,6 @@
 package com.nutomic.syncthingandroid.gui;
 
-import android.annotation.TargetApi;
 import android.app.Activity;
-import android.content.ClipData;
-import android.content.ClipboardManager;
-import android.content.Context;
 import android.os.Bundle;
 import android.support.v4.app.ActionBarDrawerToggle;
 import android.support.v4.app.Fragment;
@@ -15,7 +11,6 @@ import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.TextView;
-import android.widget.Toast;
 
 import com.nutomic.syncthingandroid.R;
 import com.nutomic.syncthingandroid.syncthing.RestApi;

src/main/java/com/nutomic/syncthingandroid/gui/NodeSettingsActivity.java

@@ -1,7 +1,6 @@
 package com.nutomic.syncthingandroid.gui;
 
 import android.annotation.SuppressLint;
-import android.annotation.TargetApi;
 import android.app.Activity;
 import android.app.AlertDialog;
 import android.content.ActivityNotFoundException;
@@ -34,7 +33,8 @@ import java.util.Map;
  */
 public class NodeSettingsActivity extends PreferenceActivity implements
 		Preference.OnPreferenceChangeListener, Preference.OnPreferenceClickListener,
-		RestApi.OnReceiveConnectionsListener, SyncthingService.OnApiChangeListener {
+		RestApi.OnReceiveConnectionsListener, SyncthingService.OnApiChangeListener,
+		RestApi.OnNodeIdNormalizedListener {
 
 	public static final String ACTION_CREATE = "create";
 
@@ -161,15 +161,16 @@ public class NodeSettingsActivity extends PreferenceActivity implements
 		switch (item.getItemId()) {
 			case R.id.create:
 				if (mNode.NodeID.equals("")) {
-					Toast.makeText(this, R.string.node_id_required, Toast.LENGTH_LONG).show();
+					Toast.makeText(this, R.string.node_id_required, Toast.LENGTH_LONG)
+							.show();
 					return true;
 				}
 				if (mNode.Name.equals("")) {
-					Toast.makeText(this, R.string.node_name_required, Toast.LENGTH_LONG).show();
+					Toast.makeText(this, R.string.node_name_required, Toast.LENGTH_LONG)
+							.show();
 					return true;
 				}
-				mSyncthingService.getApi().editNode(mNode, true, this);
-				finish();
+				mSyncthingService.getApi().editNode(mNode, this);
 				return true;
 			case R.id.share_node_id:
 				RestApi.shareNodeId(this, mNode.NodeID);
@@ -255,7 +256,7 @@ public class NodeSettingsActivity extends PreferenceActivity implements
 	 */
 	private void nodeUpdated() {
 		if (getIntent().getAction().equals(ACTION_EDIT)) {
-			mSyncthingService.getApi().editNode(mNode, false, this);
+			mSyncthingService.getApi().editNode(mNode, this);
 		}
 	}
 
@@ -287,4 +288,22 @@ public class NodeSettingsActivity extends PreferenceActivity implements
 		}
 	}
 
+	/**
+	 * Callback for {@link RestApi#editNode(RestApi.Node, RestApi.OnNodeIdNormalizedListener)}.
+	 * Displays an error message if present, or finishes the Activity on success in edit mode.
+	 *
+	 * @param normalizedId The normalized node ID, or null on error.
+	 * @param error An error message, or null on success.
+	 */
+	@Override
+	public void onNodeIdNormalized(String normalizedId, String error) {
+		if (error != null) {
+			Toast.makeText(NodeSettingsActivity.this, error,
+					Toast.LENGTH_LONG).show();
+		}
+		else if (getIntent().getAction().equals(ACTION_CREATE)) {
+			finish();
+		}
+	}
+
 }

src/main/java/com/nutomic/syncthingandroid/gui/NodesFragment.java

@@ -3,9 +3,7 @@ package com.nutomic.syncthingandroid.gui;
 import android.content.Intent;
 import android.os.Bundle;
 import android.support.v4.app.ListFragment;
-import android.view.LayoutInflater;
 import android.view.View;
-import android.view.ViewGroup;
 import android.widget.AdapterView;
 import android.widget.ListView;
 

src/main/java/com/nutomic/syncthingandroid/gui/ReposFragment.java

@@ -3,9 +3,7 @@ package com.nutomic.syncthingandroid.gui;
 import android.content.Intent;
 import android.os.Bundle;
 import android.support.v4.app.ListFragment;
-import android.view.LayoutInflater;
 import android.view.View;
-import android.view.ViewGroup;
 import android.widget.AdapterView;
 
 import com.nutomic.syncthingandroid.R;

src/main/java/com/nutomic/syncthingandroid/gui/WebGuiActivity.java

@@ -12,7 +12,6 @@ import android.view.View;
 import android.webkit.WebView;
 import android.webkit.WebViewClient;
 import android.widget.ProgressBar;
-import android.widget.TextView;
 
 import com.nutomic.syncthingandroid.R;
 import com.nutomic.syncthingandroid.syncthing.SyncthingService;

src/main/java/com/nutomic/syncthingandroid/syncthing/GetTask.java

@@ -37,6 +37,8 @@ public class GetTask extends AsyncTask<String, Void, String> {
 
 	public static final String URI_MODEL = "/rest/model";
 
+	public static final String URI_NODEID = "/rest/nodeid";
+
 	/**
 	 * params[0] Syncthing hostname
 	 * params[1] URI to call

src/main/java/com/nutomic/syncthingandroid/syncthing/RestApi.java

@@ -647,9 +647,30 @@ public class RestApi implements SyncthingService.OnWebGuiAvailableListener {
 	}
 
 	/**
-	 * Updates or creates the given node.
+	 * Updates or creates the given node, depending on whether it already exists.
+	 *
+	 * @param node Settings of the node to edit. To create a node, pass a non-existant node ID.
+	 * @param listener {@link OnNodeIdNormalizedListener} for the normalized node ID.
 	 */
-	public void editNode(Node node, boolean create, Activity activity) {
+	public void editNode(final Node node,
+			final OnNodeIdNormalizedListener listener) {
+		mSyncthingService.getApi().normalizeNodeId(node.NodeID,
+				new RestApi.OnNodeIdNormalizedListener() {
+					@Override
+					public void onNodeIdNormalized(String normalizedId, String error) {
+						listener.onNodeIdNormalized(normalizedId, error);
+						if (normalizedId == null)
+							return;
+
+						node.NodeID = normalizedId;
+						// If the node already exists, just update it.
+						boolean create = true;
+						for (RestApi.Node n : getNodes()) {
+							if (n.NodeID.equals(node.NodeID)) {
+								create = false;
+							}
+						}
+
 						try {
 							JSONArray nodes = mConfig.getJSONArray("Nodes");
 							JSONObject n = null;
@@ -669,12 +690,14 @@ public class RestApi implements SyncthingService.OnWebGuiAvailableListener {
 							n.put("NodeID", node.NodeID);
 							n.put("Name", node.Name);
 							n.put("Addresses", listToJson(node.Addresses.split(" ")));
-			configUpdated(activity);
+							configUpdated(mSyncthingService);
 						}
 						catch (JSONException e) {
 							Log.w(TAG, "Failed to read nodes", e);
 						}
 					}
+				});
+	}
 
 	/**
 	 * Deletes the given node from syncthing.
@@ -781,6 +804,42 @@ public class RestApi implements SyncthingService.OnWebGuiAvailableListener {
 		return newArray;
 	}
 
+	/**
+	 * Result listener for {@link #normalizeNodeId(String, OnNodeIdNormalizedListener)}.
+	 */
+	public interface OnNodeIdNormalizedListener {
+		/**
+		 * On any call, exactly one parameter will be null.
+		 *
+		 * @param normalizedId The normalized node ID, or null on error.
+		 * @param error An error message, or null on success.
+		 */
+		public void onNodeIdNormalized(String normalizedId, String error);
+	}
+
+	/**
+	 * Normalizes a given node ID.
+	 */
+	public void normalizeNodeId(String id, final OnNodeIdNormalizedListener listener) {
+		new GetTask() {
+			@Override
+			protected void onPostExecute(String s) {
+				super.onPostExecute(s);
+				String normalized = null;
+				String error = null;
+				try {
+					JSONObject json = new JSONObject(s);
+					normalized = json.optString("id", null);
+					error = json.optString("error", null);
+				}
+				catch (JSONException e) {
+					Log.d(TAG, "Failed to parse normalized node ID JSON", e);
+				}
+				listener.onNodeIdNormalized(normalized, error);
+			}
+		}.execute(mUrl, GetTask.URI_NODEID, mApiKey, "id", id);
+	}
+
 	public boolean isApiAvailable() {
 		return mAvailableCount.get() == TOTAL_STARTUP_CALLS;
 	}

src/main/java/com/nutomic/syncthingandroid/syncthing/SyncthingService.java

@@ -36,7 +36,6 @@ import java.io.InputStreamReader;
 import java.lang.ref.WeakReference;
 import java.util.HashSet;
 import java.util.Iterator;
-import java.util.concurrent.locks.ReentrantLock;
 
 /**
  * Holds the native syncthing instance and provides an API to access it.