FieldCommands.h

#pragma once
 
#include "EditorCommand.h"
 
namespace Cogs::Core
{
  struct FieldInfo
  {
    Reflection::TypeId componentId;
    Reflection::FieldId fieldId;
  };
 
  template<typename T>
  struct SetFieldCommand : public EditorCommand
  {
    SetFieldCommand(EditorState * state, EntityIds entityIds, FieldInfo fieldInfo, T fieldData)
      : EditorCommand(state, state->context), entityIds(entityIds), fieldInfo(fieldInfo), fieldData(fieldData)
    {
    }
 
    void close() override
    {
      // Don't close field commands. Allow merging several
    }
 
    void apply() override
    {
      for (auto & id : entityIds) {
        auto entity = context->store->getEntityPtr(id);
        auto component = entity->getComponent(fieldInfo.componentId);
        auto & fieldType = Reflection::TypeDatabase::getType(fieldInfo.componentId);
        auto field = fieldType.getField(fieldInfo.fieldId);
        auto fieldPtr = field->template getPtr<T>(component);
 
        previousDatas.push_back(*fieldPtr);
 
        *fieldPtr = fieldData;
 
        component->setFieldChanged(fieldInfo.fieldId);
      }
    }
 
    void undo() override
    {
      for (size_t i = 0; i < entityIds.size(); ++i) {
        auto entity = context->store->getEntityPtr(entityIds[i]);
        auto component = entity->getComponent(fieldInfo.componentId);
        auto & fieldType = Reflection::TypeDatabase::getType(fieldInfo.componentId);
        auto field = fieldType.getField(fieldInfo.fieldId);
        auto fieldPtr = field->template getPtr<T>(component);
 
        *fieldPtr = previousDatas[i];
 
        component->setFieldChanged(fieldInfo.fieldId);
      }
 
      previousDatas.clear();
    }
 
    bool mergeWith(const EditorCommand * command) override
    {
      auto setFieldCommand = dynamic_cast<const SetFieldCommand<T> *>(command);
 
      if (!setFieldCommand) {
        return false;
      }
 
      if (entityIds != setFieldCommand->entityIds) {
        return false;
      }
 
      if (fieldInfo.componentId != setFieldCommand->fieldInfo.componentId || fieldInfo.fieldId != setFieldCommand->fieldInfo.fieldId) {
        return false;
      }
 
      fieldData = setFieldCommand->fieldData;
 
      return true;
    }
 
  private:
    EntityIds entityIds;
    FieldInfo fieldInfo;
    T fieldData;
 
    std::vector<T> previousDatas;
  };
}