src/SimpleLayout.h

#pragma once
#include "imgui.h"
#include "imgui_internal.h"
#include <functional>

class SimpleLayout {
public:
    // 使用函数对象代替函数指针，更现代的C++风格
    using WindowCallback = std::function<void()>;

    SimpleLayout(float splitRatio = 0.5f)
        : m_splitRatio(splitRatio)
        , m_splitBarWidth(4.0f)
        , m_isDragging(false)
        , m_splitBarHeld(false)
        , m_splitBarDelta(0.0f)
    {}

    void SetLeftWindow(WindowCallback callback) { m_leftWindow = callback; }
    void SetRightWindow(WindowCallback callback) { m_rightWindow = callback; }

    void Draw() {
        ImGuiViewport* viewport = ImGui::GetMainViewport();
        ImVec2 pos = viewport->WorkPos;
        ImVec2 size = viewport->WorkSize;

        // 计算左右窗口的位置和大小
        float splitX = pos.x + size.x * m_splitRatio;
        
        // 绘制左窗口
        if (m_leftWindow) {
            ImGui::SetNextWindowPos(ImVec2(pos.x, pos.y));
            ImGui::SetNextWindowSize(ImVec2(splitX - pos.x - m_splitBarWidth/2, size.y));
            ImGui::Begin("Left Window", nullptr, ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoTitleBar);
            m_leftWindow();
            ImGui::End();
        }

        // 绘制右窗口
        if (m_rightWindow) {
            ImGui::SetNextWindowPos(ImVec2(splitX + m_splitBarWidth/2, pos.y));
            ImGui::SetNextWindowSize(ImVec2(size.x - (splitX - pos.x) - m_splitBarWidth/2, size.y));
            ImGui::Begin("Right Window", nullptr, ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoTitleBar);
            m_rightWindow();
            ImGui::End();
        }

        // 处理分隔条
        ImGui::SetNextWindowPos(ImVec2(splitX - m_splitBarWidth/2, pos.y));
        ImGui::SetNextWindowSize(ImVec2(m_splitBarWidth, size.y));
        ImGui::PushStyleColor(ImGuiCol_WindowBg, ImVec4(0.3f, 0.3f, 0.3f, 1.0f));
        ImGui::Begin("##Splitter", nullptr, 
            ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoResize | 
            ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoBringToFrontOnFocus);

        // 处理拖拽
        if (!m_splitBarHeld) {
            // 检测鼠标是否悬停在分隔条上
            ImVec2 splitBarMin = ImGui::GetWindowPos();
            ImVec2 splitBarMax = ImVec2(splitBarMin.x + ImGui::GetWindowSize().x,
                                       splitBarMin.y + ImGui::GetWindowSize().y);
            
            if (ImGui::IsMouseHoveringRect(splitBarMin, splitBarMax, false)) {
                ImGui::SetMouseCursor(ImGuiMouseCursor_ResizeEW);
                
                if (ImGui::IsMouseClicked(ImGuiMouseButton_Left)) {
                    m_splitBarHeld = true;
                    m_splitBarDelta = splitX - ImGui::GetMousePos().x;
                }
            }
        } else {
            if (ImGui::IsMouseDown(ImGuiMouseButton_Left)) {
                ImGui::SetMouseCursor(ImGuiMouseCursor_ResizeEW);
                
                // 计算新的分隔比例
                float newSplitX = ImGui::GetMousePos().x + m_splitBarDelta;
                float newRatio = (newSplitX - pos.x) / size.x;
                
                // 限制分隔条的移动范围
                m_splitRatio = ImClamp(newRatio, 0.1f, 0.9f);
            } else {
                m_splitBarHeld = false;
            }
        }

        ImGui::End();
        ImGui::PopStyleColor();
    }

private:
    float m_splitRatio;        // 分割比例（0-1）
    float m_splitBarWidth;     // 分隔条宽度
    bool m_isDragging;         // 是否正在拖拽（已废弃）
    bool m_splitBarHeld;       // 分隔条是否被按住
    float m_splitBarDelta;     // 鼠标按下时与分隔条的位置差
    WindowCallback m_leftWindow;  // 左窗口回调
    WindowCallback m_rightWindow; // 右窗口回调
};