From cebb1a2cf85aa2c779b0ceb4a9372a23cde095f6 Mon Sep 17 00:00:00 2001
From: Sri Sham Haran <s.srishamharan@digipen.edu>
Date: Tue, 27 Sep 2022 21:06:25 +0800
Subject: [PATCH] Deserialization WIP

---
 .../src/Serialization/SHSerialization.cpp     | 92 ++++++++++++++++---
 .../src/Serialization/SHSerialization.h       | 17 +++-
 2 files changed, 94 insertions(+), 15 deletions(-)

diff --git a/SHADE_Engine/src/Serialization/SHSerialization.cpp b/SHADE_Engine/src/Serialization/SHSerialization.cpp
index 25358805..926e4ff5 100644
--- a/SHADE_Engine/src/Serialization/SHSerialization.cpp
+++ b/SHADE_Engine/src/Serialization/SHSerialization.cpp
@@ -4,6 +4,7 @@
 
 #include <yaml-cpp/yaml.h>
 
+#include "ECS_Base/Managers/SHEntityManager.h"
 #include "Scene/SHSceneManager.h"
 #include "Tools/SHException.h"
 
@@ -29,18 +30,60 @@ namespace SHADE
     auto root = sceneGraph.GetRoot();
 
     SHASSERT(root != nullptr, "Root is null. Failed to serialize scene to node.");
-
+  
     auto const& children = root->GetChildren();
     out << YAML::BeginDoc;
-    for (auto child : children)
-    {
-      out << YAML::BeginSeq;
-      out << SerializeEntityToNode(child);
-      out << YAML::EndSeq;
-    }
+
+    auto pred = [&out](SHSceneNode* node){out << SerializeEntityToNode(node);};
+    sceneGraph.Traverse(pred);
+      //out << SerializeEntityToNode(child);
+    
     out << YAML::EndDoc;
   }
 
+  static void DeserializeEntity(YAML::iterator& it, YAML::Node const& node, std::vector<EntityID>& createdEntities, EntityID parentEID = MAX_EID)
+  {
+    if(!node[EIDNode])
+      return;
+    EntityID eid = node[EIDNode].as<EntityID>();
+    std::string name = "Default";
+    if(node[EntityNameNode])
+      name = node[EntityNameNode].as<std::string>();
+    //Compile component IDs
+    const auto componentIDList = SHSerialization::GetComponentIDList(node[ComponentsNode]);
+    eid = SHEntityManager::CreateEntity(componentIDList, eid, name, parentEID);
+    createdEntities.push_back(eid);
+    if(node[NumberOfChildrenNode])
+    {      int numOfChildren = node[NumberOfChildrenNode].as<int>();
+      for(int i = 0; i < numOfChildren; ++i)
+      {
+        DeserializeEntity(it, *it, createdEntities, eid);
+        ++it;
+      }
+    }
+  }
+
+  void SHSerialization::DeserializeSceneFromFile(std::string const& fileData)
+  {
+    YAML::Node entities = YAML::Load(fileData.c_str());
+    std::vector<EntityID> createdEntities{};
+
+    //Create Entities
+    for(auto it = entities.begin(); it != entities.end(); ++it)
+    {
+      DeserializeEntity(it, (*it), createdEntities);
+    }
+
+    //Initialize Entity
+    for(auto it = entities.begin(); it != entities.end(); ++it)
+    {
+      //For each node, Deserialize component
+        //Recurse through properties 
+    }
+  }
+
+
+
   std::string SHSerialization::SerializeEntityToString()
   {
     return std::string();
@@ -53,16 +96,19 @@ namespace SHADE
   YAML::Node SHSerialization::SerializeEntityToNode(SHSceneNode* sceneNode)
   {
     YAML::Node node;
-    if (!sceneNode)
+    auto eid = sceneNode->GetEntityID();
+    auto entity = SHEntityManager::GetEntityByID(eid);
+    if (!sceneNode || !entity)
     {
       node = YAML::Null;
       return node;
     }
-    auto eid = sceneNode->GetEntityID();
-    node["EID"] = eid;
-    node["isActive"] = sceneNode->IsActive();
+
+    node[EIDNode] = eid;
+    node[EntityNameNode] = entity->name;
+    node[IsActiveNode] = sceneNode->IsActive();
     auto const& children = sceneNode->GetChildren();
-    node["NumberOfChildren"] = children.size();
+    node[NumberOfChildrenNode] = children.size();
 
     YAML::Node components;
 
@@ -70,7 +116,27 @@ namespace SHADE
     {
       components[rttr::type::get<SHTransformComponent>().get_name().data()] = SHSerializationHelper::SerializeComponentToNode(transform);
     }
-    node["Components"] = components;
+    node[ComponentsNode] = components;
     return node;
   }
+
+  template<typename ComponentType, std::enable_if_t<std::is_base_of_v<SHComponent, ComponentType>, bool> = true>
+   std::optional<ComponentTypeID> GetComponentID(YAML::Node const & componentNode)
+  {
+    if(componentNode[rttr::type::get<ComponentType>().get_name().data()])
+      return {SHFamilyID<SHComponent>::GetID<ComponentType>()};
+    else
+      return std::nullopt;
+  }
+
+  std::vector<ComponentTypeID> SHSerialization::GetComponentIDList(YAML::Node const& componentsNode)
+  {
+    std::vector<ComponentTypeID> componentIDList;
+
+    auto id = GetComponentID<SHTransformComponent>(componentsNode);
+    if(id.has_value())
+      componentIDList.push_back(id.value());
+
+    return componentIDList;
+  }
 }
diff --git a/SHADE_Engine/src/Serialization/SHSerialization.h b/SHADE_Engine/src/Serialization/SHSerialization.h
index 0611e4d2..022a01c4 100644
--- a/SHADE_Engine/src/Serialization/SHSerialization.h
+++ b/SHADE_Engine/src/Serialization/SHSerialization.h
@@ -5,7 +5,7 @@
 #include <filesystem>
 
 #include <ECS_Base/Components/SHComponent.h>
-#include "SH_API.h"
+
 namespace YAML
 {
   class Emitter;
@@ -15,14 +15,27 @@ namespace YAML
 namespace SHADE
 {
   class SHSceneNode;
+
+  constexpr const char* ComponentsNode = "Components";
+  constexpr const char* EntityNameNode = "Name";
+  constexpr const char* EIDNode = "EID";
+  constexpr const char* IsActiveNode = "IsActive";
+  constexpr const char* NumberOfChildrenNode = "NumberOfChildren";
+
   struct SH_API SHSerialization
   {
+    //TODO: change paths to resource ID
     static void SerializeSceneToFile(std::filesystem::path const& path);
     static std::string SerializeSceneToString();
     static void SerializeSceneToEmitter(YAML::Emitter& out);
-
+    static void DeserializeSceneFromFile(std::string const& fileData);
+    
+    
     static std::string SerializeEntityToString();
     static void SerializeEntityToFile(std::filesystem::path const& path);
     static YAML::Node SerializeEntityToNode(SHSceneNode* sceneNode);
+
+    static std::vector<ComponentTypeID> GetComponentIDList(YAML::Node const& componentsNode);
+  private:
   };
 }
\ No newline at end of file