Hazel/Sandbox/src/Editor/Panels/SceneHierachyPanel.cpp

//
// Created by sfd on 25-5-29.
//

#include "SceneHierachyPanel.h"
#include <imgui.h>
#include <imgui_internal.h>
#include <glm/gtc/type_ptr.hpp>
#include <Hazel/Scene/Components.h>

namespace Hazel
{
    SceneHierachyPanel::SceneHierachyPanel(const Ref<Scene>& context)
    {
        SetContext(context);
    }

    void SceneHierachyPanel::SetContext(const Ref<Scene>& context)
    {
        m_Context = context;
        m_SelectionContext = {};
    }

    void SceneHierachyPanel::OnImGuiRender()
    {
        ImGui::Begin("Scene Hierachy");

        m_Context->m_Registry.view<entt::entity>().each([&](auto entityID)
        {
            DrawEntityNode({entityID, m_Context.get()});
        });

        if (ImGui::IsMouseDown(0) && ImGui::IsWindowHovered())
        {
            m_SelectionContext = { };
        }

        if (ImGui::BeginPopupContextWindow(0, ImGuiPopupFlags_MouseButtonRight | ImGuiPopupFlags_NoOpenOverItems))
        {
            if (ImGui::MenuItem("Create Empty Entity"))
                m_Context->CreateEntity("Empty Entity");
            ImGui::EndPopup();
        }

        ImGui::End();

        ImGui::Begin("Properties");
        if (m_SelectionContext)
        {
            DrawComponents(m_SelectionContext);
        }
        ImGui::End();
    }


    void SceneHierachyPanel::DrawEntityNode(Entity entity)
    {
        auto& tag = entity.GetComponent<TagComponent>().Tag;
        bool entityDeleted = false;

        ImGuiTreeNodeFlags flags = ((m_SelectionContext == entity) ? ImGuiTreeNodeFlags_Selected : 0) | ImGuiTreeNodeFlags_OpenOnArrow;
        flags |= ImGuiTreeNodeFlags_SpanAvailWidth;
        const bool isopened = ImGui::TreeNodeEx((void*)(uint64_t)(uint32_t)entity, flags, tag.c_str());
        if (ImGui::IsItemClicked())
        {
            m_SelectionContext = entity;
        }

        if (ImGui::BeginPopupContextItem())
        {
            if (ImGui::MenuItem("Delete Entity"))
                entityDeleted = true;
            ImGui::EndPopup();
        }

        if (isopened)
        {
            ImGui::TreePop();
        }

        if (entityDeleted)
        {
            m_Context->DestoryEntity(entity);
            if (m_SelectionContext == entity)
            {
                m_SelectionContext = {};
            }
        }
    }

    static bool DrawVec3Control(const std::string& label, glm::vec3& values, float resetValue = 0.0f, float columnWidth = 100.0f)
    {
        ImGuiIO& io = ImGui::GetIO();
        auto boldFont = io.Fonts->Fonts[0];
        bool isChanged = false;
        ImGui::PushID(label.c_str());
        const ImGuiContext* context = ImGui::GetCurrentContext();

        ImGui::Columns(2);

        ImGui::SetColumnWidth(0, columnWidth);
        ImGui::Text(label.c_str());
        ImGui::NextColumn();

        ImGui::PushMultiItemsWidths(3, ImGui::CalcItemWidth());
        ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, {0.0f, 0.0f});

        float lineHeight = context->Font->FontSize + context->Style.FramePadding.y * 2.0f;
        // float lineHeight = GImGui->Font->FontSize + GImGui->Style.FramePadding.y * 2.0f;


        ImVec2 buttonSize = {lineHeight + 3.0f, lineHeight};

        ImGui::PushStyleColor(ImGuiCol_Button, ImVec4{0.8f, 0.1f, 0.15f, 1.0f});
        ImGui::PushStyleColor(ImGuiCol_ButtonHovered, ImVec4{0.9f, 0.2f, 0.2f, 1.0f});
        ImGui::PushStyleColor(ImGuiCol_ButtonActive, ImVec4{0.8f, 0.1f, 0.15f, 1.0f});
        ImGui::PushFont(boldFont);
        if (ImGui::Button("X", buttonSize))
        {
            values.x  = resetValue;
            isChanged = true;
        }
        ImGui::PopFont();
        ImGui::PopStyleColor(3);

        ImGui::SameLine();
        if (ImGui::DragFloat("##X", &values.x, 0.1f))
        {
            isChanged = true;
        }
        ImGui::PopItemWidth();
        ImGui::SameLine();

        ImGui::PushStyleColor(ImGuiCol_Button, ImVec4{0.2f, 0.7f, 0.2f, 1.0f});
        ImGui::PushStyleColor(ImGuiCol_ButtonHovered, ImVec4{0.3f, 0.8f, 0.3f, 1.0f});
        ImGui::PushStyleColor(ImGuiCol_ButtonActive, ImVec4{0.2f, 0.7f, 0.2f, 1.0f});
        ImGui::PushFont(boldFont);
        if (ImGui::Button("Y", buttonSize))
        {
            values.y  = resetValue;
            isChanged = true;
        }
        ImGui::PopFont();
        ImGui::PopStyleColor(3);

        ImGui::SameLine();
        if (ImGui::DragFloat("##Y", &values.y, 0.1f))
        {
            isChanged = true;
        }
        ImGui::PopItemWidth();
        ImGui::SameLine();

        ImGui::PushStyleColor(ImGuiCol_Button, ImVec4{0.1f, 0.25f, 0.8f, 1.0f});
        ImGui::PushStyleColor(ImGuiCol_ButtonHovered, ImVec4{0.2f, 0.35f, 0.9f, 1.0f});
        ImGui::PushStyleColor(ImGuiCol_ButtonActive, ImVec4{0.1f, 0.25f, 0.8f, 1.0f});
        ImGui::PushFont(boldFont);
        if (ImGui::Button("Z", buttonSize))
        {
            values.z  = resetValue;
            isChanged = true;
        }
        ImGui::PopFont();
        ImGui::PopStyleColor(3);

        ImGui::SameLine();
        if (ImGui::DragFloat("##Z", &values.z, 0.1f))
        {
            isChanged = true;
        }
        ImGui::PopItemWidth();


        ImGui::PopStyleVar();
        ImGui::Columns(1);

        ImGui::PopID();

        return isChanged;
    }

    template<typename T, typename UIfunction>
    void DrawComponent(const std::string& name, Entity entity, UIfunction uiFunction)
    {
        constexpr ImGuiTreeNodeFlags treeNodeFlags = ImGuiTreeNodeFlags_DefaultOpen | ImGuiTreeNodeFlags_Framed | ImGuiTreeNodeFlags_SpanAvailWidth | ImGuiTreeNodeFlags_AllowItemOverlap | ImGuiTreeNodeFlags_FramePadding;;

        if (entity.HasComponent<T>())
        {
            ImGui::PushID(&entity);
            auto& component = entity.GetComponent<T>();

            ImVec2 contextReginAvail = ImGui::GetContentRegionAvail();

            ImGui::PushStyleVar(ImGuiStyleVar_FramePadding, {4.0f, 4.0f});
            auto context = ImGui::GetCurrentContext();
            float lineHeight = context->Font->FontSize + context->Style.FramePadding.y * 2.0f;

            ImGui::Separator();
            bool open = ImGui::TreeNodeEx((void*)(uint64_t)typeid(T).hash_code(), treeNodeFlags, name.c_str());
            ImGui::PopStyleVar();
            ImGui::SameLine(contextReginAvail.x - lineHeight * 0.5f);
            if (ImGui::Button("+", ImVec2(lineHeight, lineHeight)))
            {
                ImGui::OpenPopup("ComponentSettings");
            }


            bool removeComponent = false;
            if (ImGui::BeginPopup("ComponentSettings"))
            {
                if (ImGui::MenuItem("Remove Component"))
                    removeComponent = true;

                ImGui::EndPopup();
            }

            if (open)
            {
                uiFunction(component);
                ImGui::TreePop();
            }

            if (removeComponent)
                entity.RemoveComponent<T>();
            ImGui::PopID();
        }
    }

    void SceneHierachyPanel::DrawComponents(Entity entity)
    {

        if (entity.HasComponent<TagComponent>())
        {
            auto& tag = entity.GetComponent<TagComponent>().Tag;

            char buffer[256] = {};
            strcpy_s(buffer,sizeof(buffer),  tag.c_str());
            if (ImGui::InputText("Tag", buffer, sizeof(buffer)))
            {
                tag = std::string(buffer);
            }
        }

        ImGui::SameLine();
        ImGui::PushItemWidth(-1);
        if (ImGui::Button("Add"))
            ImGui::OpenPopup("Add");
        if (ImGui::BeginPopup("Add"))
        {
            if (ImGui::MenuItem("Camera"))
            {
                m_SelectionContext.AddComponent<CameraComponent>();
                ImGui::CloseCurrentPopup();
            }
            if (ImGui::MenuItem("Sprite"))
            {
                m_SelectionContext.AddComponent<SpriteRendererComponent>();
                ImGui::CloseCurrentPopup();
            }

            ImGui::EndPopup();
        }
        ImGui::PopItemWidth();

        DrawComponent<TransformComponent>("Transform", entity, [](auto& component)
        {
                DrawVec3Control("Translation", component.Translation);
                glm::vec3 rotation = glm::degrees(component.Rotation);
                if (DrawVec3Control("Rotation", rotation))
                {
                    component.Rotation = glm::radians(rotation);
                }
                DrawVec3Control("Scale", component.Scale, 1.0f);

        });

        DrawComponent<CameraComponent>("Camera", entity, [](auto& component)
        {
                auto& camera = component.Camera;

                ImGui::Checkbox("isPrimary", &component.Primary);
                static const char* projectionTypeStrings[] = { "Perspective", "Orthographic" };

                const char* currentProjectionTypeString = projectionTypeStrings[(int)camera.GetProjectionType()];
                if (ImGui::BeginCombo("Projection", currentProjectionTypeString))
                {
                    for (int i = 0; i < 2; i++)
                    {
                        const bool isSelected = currentProjectionTypeString == projectionTypeStrings[i];
                        if (ImGui::Selectable(projectionTypeStrings[i], isSelected))
                        {
                            currentProjectionTypeString = projectionTypeStrings[i];
                            camera.SetProjectionType(static_cast<ScenceCamera::ProjectionType>(i));
                        }

                        if (isSelected)
                        {
                            ImGui::SetItemDefaultFocus();
                        }
                    }
                    ImGui::EndCombo();
                }

                if (camera.GetProjectionType() == ScenceCamera::ProjectionType::Perspective)
                {
                    float fov = glm::degrees(camera.GetPerspectiveVerticalFOV());
                    if (ImGui::DragFloat("FOV", &fov, 0.1f))
                        camera.SetPerspectiveVerticalFOV(glm::radians(fov));

                    float near = camera.GetPerspectiveNearCLip();
                    if (ImGui::DragFloat("Near", &near))
                        camera.SetPerspectiveNearClip(near);

                    float far = camera.GetPerspectiveFarCLip();
                    if (ImGui::DragFloat("Far", &far))
                        camera.SetPerspectiveFarClip(far);
                }
                if (camera.GetProjectionType() == ScenceCamera::ProjectionType::Orthographic)
                {
                    float size = camera.GetOrthographicSize();
                    if (ImGui::DragFloat("Size", &size))
                        camera.SetOrthographicSize(size);

                    float near = camera.GetOrthographicNearCLip();
                    if (ImGui::DragFloat("Near", &near))
                        camera.SetOrthographicNearClip(near);

                    float far = camera.GetOrthographicFarCLip();
                    if (ImGui::DragFloat("Far", &far))
                        camera.SetOrthographicFarClip(far);

                    ImGui::Checkbox("Fixed Aspect Ratio", &component.FixedAspectRatio);
                }
        });

        DrawComponent<SpriteRendererComponent>("Sprite Renderer", entity, [](auto& component)
        {
            ImGui::ColorEdit4("Color", glm::value_ptr(component.Color));
        });
    }
}