runelite-api: fix widget children lookup logic

Also update dev tools panel widget tree to use show all widgets children,
and start from the root widgets.

Thanks to @rsbmatt for his assistance in explaining the logic

runelite-api/src/main/java/net/runelite/api/Client.java

@@ -26,6 +26,7 @@ package net.runelite.api;
 
 import java.awt.Canvas;
 import java.util.Arrays;
+import java.util.Objects;
 import net.runelite.api.widgets.Widget;
 import net.runelite.api.widgets.WidgetInfo;
 import net.runelite.rs.api.ItemComposition;
@@ -213,13 +214,14 @@ public class Client
 		return client.getBaseY();
 	}
 
-	public Widget[][] getWidgets()
+	public Widget[] getWidgetRoots()
 	{
-		return Arrays.stream(client.getWidgets())
-			.map(parent -> parent != null ? Arrays.stream(parent)
-			.map(child -> child != null ? new Widget(this, child) : null)
-			.toArray(Widget[]::new) : null
-			).toArray(Widget[][]::new);
+		int topGroup = client.getWidgetRoot();
+		return Arrays.stream(client.getWidgets()[topGroup])
+			.filter(Objects::nonNull)
+			.filter(w -> w.getParentId() == -1) // is a root
+			.map(w -> new Widget(this, w))
+			.toArray(Widget[]::new);
 	}
 
 	public Widget getWidget(WidgetInfo widget)
@@ -230,6 +232,21 @@ public class Client
 		return getWidget(groupId, childId);
 	}
 
+	public Widget[] getGroup(int groupId)
+	{
+		net.runelite.rs.api.Widget[][] widgets = client.getWidgets();
+
+		if (widgets == null || groupId < 0 || groupId >= widgets.length)
+		{
+			return null;
+		}
+
+		return Arrays.stream(widgets[groupId])
+			.filter(Objects::nonNull)
+			.map(w -> new Widget(this, w))
+			.toArray(Widget[]::new);
+	}
+
 	public Widget getWidget(int groupId, int childId)
 	{
 		net.runelite.rs.api.Widget[][] widgets = client.getWidgets();
@@ -258,11 +275,6 @@ public class Client
 		return client.getWidgetPositionsY();
 	}
 
-	public boolean[] getValidInterfaces()
-	{
-		return client.getValidInterfaces();
-	}
-
 	public String[] getPlayerOptions()
 	{
 		return client.getPlayerOptions();

runelite-api/src/main/java/net/runelite/api/widgets/Widget.java

@@ -26,13 +26,17 @@ package net.runelite.api.widgets;
 
 import java.awt.Rectangle;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
+import java.util.Objects;
 import net.runelite.api.Client;
 import net.runelite.api.Node;
 import net.runelite.api.Point;
 import net.runelite.api.WidgetNode;
 import net.runelite.api.XHashTable;
+import static net.runelite.api.widgets.WidgetInfo.TO_CHILD;
+import static net.runelite.api.widgets.WidgetInfo.TO_GROUP;
 
 public class Widget
 {
@@ -70,7 +74,7 @@ public class Widget
 			return null;
 		}
 
-		return client.getWidget(id >>> 16, id & 0xFFFF);
+		return client.getWidget(TO_GROUP(id), TO_CHILD(id));
 	}
 
 	public int getParentId()
@@ -81,7 +85,7 @@ public class Widget
 			return parentId;
 		}
 
-		int i = getId() >>> 16;
+		int i = TO_GROUP(getId());
 		XHashTable componentTable = client.getComponentTable();
 		for (Node node : componentTable.getNodes())
 		{
@@ -96,6 +100,70 @@ public class Widget
 		return -1;
 	}
 
+	public Widget getChild(int index)
+	{
+		net.runelite.rs.api.Widget[] widgets = widget.getChildren();
+
+		if (widgets == null || widgets[index] == null)
+		{
+			return null;
+		}
+
+		return new Widget(client, widgets[index]);
+	}
+
+	public Widget[] getDynamicChildren()
+	{
+		net.runelite.rs.api.Widget[] children = widget.getChildren();
+
+		if (children == null)
+		{
+			return new Widget[0];
+		}
+
+		return Arrays.stream(children)
+			.filter(Objects::nonNull)
+			.filter(w -> w.getParentId() == getId())
+			.map(w -> new Widget(client, w))
+			.toArray(Widget[]::new);
+	}
+
+	public Widget[] getStaticChildren()
+	{
+		return Arrays.stream(client.getGroup(TO_GROUP(getId())))
+			.filter(Objects::nonNull)
+			.filter(w -> w.getParentId() == getId())
+			.toArray(Widget[]::new);
+	}
+
+	public Widget[] getNestedChildren()
+	{
+		XHashTable componentTable = client.getComponentTable();
+		int group = -1;
+
+		// XXX can actually use hashtable lookup instead of table
+		// iteration here...
+		for (Node node : componentTable.getNodes())
+		{
+			WidgetNode wn = (WidgetNode) node;
+
+			if (wn.getHash() == getId())
+			{
+				group = wn.getId();
+				break;
+			}
+		}
+
+		if (group == -1)
+		{
+			return new Widget[0];
+		}
+
+		return Arrays.stream(client.getGroup(group))
+			.filter(w -> w.getParentId() == getId())
+			.toArray(Widget[]::new);
+	}
+
 	private int getRelativeX()
 	{
 		return widget.getRelativeX();
@@ -264,37 +332,6 @@ public class Widget
 		return widget.getPaddingY();
 	}
 
-	public Widget[] getChildren()
-	{
-		net.runelite.rs.api.Widget[] widgets = widget.getChildren();
-
-		if (widgets == null)
-		{
-			return null;
-		}
-
-		Widget[] children = new Widget[widgets.length];
-
-		for (int i = 0; i < widgets.length; ++i)
-		{
-			children[i] = getChild(i);
-		}
-
-		return children;
-	}
-
-	public Widget getChild(int index)
-	{
-		net.runelite.rs.api.Widget[] widgets = widget.getChildren();
-
-		if (widgets == null || widgets[index] == null)
-		{
-			return null;
-		}
-
-		return new Widget(client, widgets[index]);
-	}
-
 	public int getItemId()
 	{
 		return widget.getItemId();

runelite-api/src/main/java/net/runelite/api/widgets/WidgetInfo.java

@@ -89,4 +89,14 @@ public enum WidgetInfo
 		return childId;
 	}
 
+	public static int TO_GROUP(int id)
+	{
+		return id >>> 16;
+	}
+
+	public static int TO_CHILD(int id)
+	{
+		return id & 0xFFFF;
+	}
+
 }