From 8d458f2633ba6d0de5ffb2816c2ea828d644c53c Mon Sep 17 00:00:00 2001
From: Diogo Miranda <diogomsmiranda@tecnico.ulisboa.pt>
Date: Sun, 3 Mar 2024 16:49:42 +0000
Subject: [PATCH] feat(tesseratos): show childOf hierarchy on world inspector

---
 CHANGELOG.md                                  |  1 +
 .../src/tesseratos/world_inspector/plugin.cpp | 74 +++++++++++++------
 2 files changed, 53 insertions(+), 22 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index de27345376..c7676ef2a2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,6 +19,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - New feature guide focused on queries (#995, **@RiscadoA**).
 - ECS Statistics tesseratos plugin (#1024, **@RiscadoA**).
 - Global position, rotation and scale getters (#1002, **@DiogoMendonc-a**).
+- Show childOf hierarchy on the world inspector (#991, **@diogomsmiranda**).
 
 ### Fixed
 
diff --git a/tools/tesseratos/src/tesseratos/world_inspector/plugin.cpp b/tools/tesseratos/src/tesseratos/world_inspector/plugin.cpp
index c8c76e9070..d5a2971082 100644
--- a/tools/tesseratos/src/tesseratos/world_inspector/plugin.cpp
+++ b/tools/tesseratos/src/tesseratos/world_inspector/plugin.cpp
@@ -4,6 +4,7 @@
 #include <cubos/core/ecs/query/opt.hpp>
 
 #include <cubos/engine/imgui/plugin.hpp>
+#include <cubos/engine/transform/child_of.hpp>
 
 #include <tesseratos/entity_selector/plugin.hpp>
 #include <tesseratos/toolbox/plugin.hpp>
@@ -14,9 +15,54 @@ using cubos::core::ecs::Name;
 using cubos::core::ecs::Opt;
 using cubos::core::ecs::Query;
 using cubos::core::ecs::World;
+using cubos::core::ecs::WriteResource;
+using cubos::engine::ChildOf;
 
 using cubos::engine::Cubos;
 
+static void show(Entity entity, Query<Entity, Opt<const Name&>, const ChildOf&, Entity> childOf, Opt<const Name&> name,
+                 tesseratos::EntitySelector& selector)
+{
+    auto displayName = name.contains() ? name->value : std::to_string(entity.index);
+    auto children = childOf.pin(1, entity);
+    auto bg_color = (ImVec4)ImColor(0, 0, 0);
+    auto text_color = (ImVec4)ImColor(255, 255, 255);
+
+    // check if entity has children
+    if (children.empty())
+    {
+        selector.selection == entity ? text_color = (ImVec4)ImColor(149, 252, 75)
+                                     : text_color = (ImVec4)ImColor(255, 255, 255);
+
+        ImGui::PushStyleColor(ImGuiCol_Text, text_color);
+        ImGui::PushStyleColor(ImGuiCol_FrameBgHovered, bg_color);
+
+        ImGui::BulletText("%s", displayName.c_str());
+        ImGui::PopStyleColor(2);
+
+        if (ImGui::IsItemClicked(0))
+        {
+            selector.selection = entity;
+        }
+
+        return;
+    }
+
+    if (ImGui::TreeNode(displayName.c_str()))
+    {
+        if (ImGui::IsItemClicked(0))
+        {
+            selector.selection = entity;
+        }
+
+        for (auto [child, nameChild, _, parent] : children)
+        {
+            show(child, childOf, nameChild, selector);
+        }
+        ImGui::TreePop();
+    }
+}
+
 void tesseratos::worldInspectorPlugin(Cubos& cubos)
 {
     cubos.addPlugin(cubos::engine::imguiPlugin);
@@ -24,7 +70,8 @@ void tesseratos::worldInspectorPlugin(Cubos& cubos)
     cubos.addPlugin(entitySelectorPlugin);
     cubos.system("show World Inspector UI")
         .tagged("cubos.imgui")
-        .call([](World& world, Query<Entity, Opt<const Name&>> query) {
+        .call([](World& world, Query<Entity, Opt<const Name&>> all,
+                 Query<Entity, Opt<const Name&>, const ChildOf&, Entity> query) {
             if (!(world.write<Toolbox>().get().isOpen("World Inspector")))
             {
                 return;
@@ -35,28 +82,11 @@ void tesseratos::worldInspectorPlugin(Cubos& cubos)
             ImGui::Begin("World Inspector");
             if (!ImGui::IsWindowCollapsed())
             {
-                int n = 0;
-                for (auto [entity, name] : query)
+                for (auto [entity, name] : all)
                 {
-                    ImGui::PushID(n);
-
-                    if (name.contains())
-                    {
-                        ImGui::BulletText("%s", name->value.c_str());
-                    }
-                    else
-                    {
-                        ImGui::BulletText("%s", std::to_string(entity.index).c_str());
-                    }
-
-                    ImGui::SameLine();
-                    if (ImGui::Button("Select"))
-                    {
-                        selector.get().selection = entity;
-                    }
-
-                    n++;
-                    ImGui::PopID();
+                    if (query.pin(0, entity).first().contains())
+                        continue; // Skip all entities with parents
+                    show(entity, query, name, selector.get());
                 }
             }
             ImGui::End();