//
// Editor.cpp：docking 骨架实现。
//
// 布局方案（首帧 DockBuilder 一次，之后 imgui.ini 接管）：
//   ┌──────────────────────────────┬───────────────┐
//   │ Hierarchy          │               │
//   ├──────────────────────────────┤   Inspector    │
//   │ Stats              │   (28%)        │
//   └──────────────────────────────┴───────────────┘
//

#include "Editor.h"
#include "HierarchyPanel.h"
#include "InspectorPanel.h"
#include "ViewportPanel.h"
#include "StatsPanel.h"

#include <imgui.h>
#include <imgui_internal.h>   // DockBuilder*（内部 API）

#include <GLFW/glfw3.h>

using namespace Engine;   // kDisplayViewport / kDisplayDirect（SceneTypes.h）

Editor::Editor() = default;

Editor::~Editor() = default;

void Editor::Init(const EditorContext& ctx)
{
    m_Ctx = ctx;

    m_Hierarchy = std::make_unique<HierarchyPanel>();
    m_Inspector = std::make_unique<InspectorPanel>();
    m_Viewport = std::make_unique<ViewportPanel>();
    m_Stats = std::make_unique<StatsPanel>();
}

void Editor::Draw()
{
    // host 窗口：铺满主视口，承载菜单栏 + DockSpace
    ImGuiViewport* viewport = ImGui::GetMainViewport();
    ImGui::SetNextWindowPos(viewport->Pos);
    ImGui::SetNextWindowSize(viewport->Size);
    ImGui::SetNextWindowViewport(viewport->ID);

    ImGui::PushStyleVar(ImGuiStyleVar_WindowRounding, 0.0f);
    ImGui::PushStyleVar(ImGuiStyleVar_WindowBorderSize, 0.0f);
    ImGui::PushStyleVar(ImGuiStyleVar_WindowPadding, ImVec2(0.0f, 0.0f));
    ImGui::Begin("##EditorDockHost", nullptr,
                 ImGuiWindowFlags_MenuBar | ImGuiWindowFlags_NoDocking |
                 ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoCollapse |
                 ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoMove |
                 ImGuiWindowFlags_NoBringToFrontOnFocus |
                 ImGuiWindowFlags_NoNavFocus);
    ImGui::PopStyleVar(3);

    DrawMenuBar();
    DrawDockSpace();

    ImGui::End();

    // 常规面板窗口（窗口名 = docking 身份）
    if (m_ShowHierarchy) m_Hierarchy->Draw(m_Ctx, m_Selected);
    if (m_ShowInspector) m_Inspector->Draw(m_Ctx, m_Selected);
    if (m_ShowViewport)
    {
        if (auto picked = m_Viewport->Draw(m_Ctx, m_VpInput)) {
            SelectEntity(*picked);   // Viewport 点击拾取 → 选中联动 Inspector/Hierarchy
        }
    }
    if (m_ShowStats)     m_Stats->Draw(m_Ctx);

    DrawQuitModal();
}

// 输入归属判定：ImGui 侧经自身后端链式回调永远正常收输入，这里
// 只决定"剩余输入给不给游戏侧"。UI 被隐藏（反引号）时不会走到
// Draw → m_VpInput 停在旧值，谓词调用方（SandboxApp）须先查
// GetImGuiEnabled() 再问这里。
bool Editor::BlockingKeyboard() const
{
    const ImGuiIO& io = ImGui::GetIO();
    if (io.WantTextInput) return true;   // 打字中（改名等）不让位快捷键

    // 游戏形态（Fullscreen）：WASD 全窗口生效，键盘只让位文本输入
    if (m_Ctx.renderer &&
        m_Ctx.renderer->GetDisplayMode() == kDisplayDirect)
    {
        return false;
    }

    // 编辑器形态：Viewport 面板持焦才拥有键盘（UE Scene view 语义）
    return !m_VpInput.focused;
}

bool Editor::BlockingMouse() const
{
    // 游戏形态：沿用 ImGui 全局判定（UI 隐藏时 WantCaptureMouse=false）
    if (m_Ctx.renderer &&
        m_Ctx.renderer->GetDisplayMode() == kDisplayDirect)
    {
        return ImGui::GetIO().WantCaptureMouse;
    }

    // 编辑器形态：悬停 Viewport 才放行（模态框遮挡时 hovered=false）
    return !m_VpInput.hovered;
}

void Editor::DrawMenuBar()
{
    if (!ImGui::BeginMenuBar())
    {
        return;
    }

    if (ImGui::BeginMenu("File"))
    {
        if (ImGui::MenuItem("Quit", "Alt+F4"))
        {
            RequestQuit();
        }
        ImGui::EndMenu();
    }

    if (ImGui::BeginMenu("View"))
    {
        ImGui::MenuItem("Hierarchy", nullptr, &m_ShowHierarchy);
        ImGui::MenuItem("Inspector", nullptr, &m_ShowInspector);
        ImGui::MenuItem("Viewport", nullptr, &m_ShowViewport);
        ImGui::MenuItem("Stats", nullptr, &m_ShowStats);
        ImGui::EndMenu();
    }

    ImGui::EndMenuBar();
}

void Editor::DrawDockSpace()
{
    const ImGuiID dockspaceId = ImGui::GetID("EditorDockSpace");

    // 默认布局：仅当 dock node 不存在时构建一次
    //（imgui.ini 已保存过布局 → DockBuilderGetNode 非空 → 跳过）
    if (!m_LayoutBuilt && ImGui::DockBuilderGetNode(dockspaceId) == nullptr)
    {
        m_LayoutBuilt = true;

        ImGui::DockBuilderRemoveNode(dockspaceId);
        ImGui::DockBuilderAddNode(dockspaceId, ImGuiDockNodeFlags_DockSpace);
        ImGui::DockBuilderSetNodeSize(dockspaceId, ImGui::GetMainViewport()->Size);

        ImGuiID dockLeft = 0, dockRight = 0, dockCenter = 0, dockStats = 0;
        ImGui::DockBuilderSplitNode(dockspaceId, ImGuiDir_Left, 0.20f,
                                    &dockLeft, &dockCenter);
        ImGui::DockBuilderSplitNode(dockCenter, ImGuiDir_Right, 0.28f,
                                    &dockRight, &dockCenter);
        ImGui::DockBuilderSplitNode(dockLeft, ImGuiDir_Down, 0.38f,
                                    &dockStats, &dockLeft);

        ImGui::DockBuilderDockWindow("Hierarchy", dockLeft);
        ImGui::DockBuilderDockWindow("Stats", dockStats);
        ImGui::DockBuilderDockWindow("Inspector", dockRight);
        ImGui::DockBuilderDockWindow("Viewport", dockCenter);

        ImGui::DockBuilderFinish(dockspaceId);
    }

    ImGui::DockSpace(dockspaceId, ImVec2(0.0f, 0.0f),
                     ImGuiDockNodeFlags_None);
}

void Editor::DrawQuitModal()
{
    if (m_ShowQuitConfirm)
    {
        ImGui::OpenPopup("Should quit?");
        m_ShowQuitConfirm = false;
    }

    ImGui::SetNextWindowPos(
        ImGui::GetMainViewport()->GetCenter(),
        ImGuiCond_Appearing, ImVec2(0.5f, 0.5f));

    if (ImGui::BeginPopupModal("Should quit?", nullptr,
                               ImGuiWindowFlags_AlwaysAutoResize))
    {
        ImGui::TextUnformatted("Quit the application?");
        ImGui::Separator();
        if (ImGui::Button("Yes", ImVec2(120, 0)))
        {
            m_QuitConfirmed = true;
            ImGui::CloseCurrentPopup();
        }
        ImGui::SameLine();
        if (ImGui::Button("No", ImVec2(120, 0)))
        {
            ImGui::CloseCurrentPopup();
        }
        ImGui::EndPopup();
    }

    if (m_QuitConfirmed)
    {
        m_QuitConfirmed = false;
        m_Ctx.app->Close();
    }
}