#ifndef Toolbox_Roll_Widget_H
#define Toolbox_Roll_Widget_H
#include <QObject>
#include <QHBoxLayout>
#include <algorithm>
#include <functional>
#include <vector>
namespace Flex_Qt {
template <typename T>
class Roll_Object : QObject {
public:
    explicit Roll_Object(QObject* parent = nullptr) : QObject(parent) {}
    explicit Roll_Object(std::vector<T*> widgets, std::function<void(T*)> enter_func,
                         std::function<void(T*)> leave_func, QObject* parent) :
        widgets(std::move(widgets)), enter_func(enter_func), leave_func(leave_func), QObject(parent) {
        if (!this->widgets.empty() && enter_func) enter_func(this->widgets[index]);
    }
    int index = 0;
    std::vector<T*> widgets;
    std::function<void(T*)> enter_func;
    std::function<void(T*)> leave_func;
    T* cur() {
        if (widgets.empty()) return nullptr;
        return widgets[index];
    }
    void set_cur(T* cur) {
        if (widgets.empty()) return;
        auto it = std::find(widgets.begin(), widgets.end(), cur);
        if (it == widgets.end()) return;
        int new_index = static_cast<int>(std::distance(widgets.begin(), it));
        if (leave_func) leave_func(widgets[index]);
        index = new_index;
        if (enter_func) enter_func(widgets[index]);
        widgets[index]->update();
    }
    void roll_right() {
        if (widgets.empty()) return;
        if (leave_func) leave_func(widgets[index]);
        widgets[index]->update();
        if (widgets.back() != widgets[index]) {
            index++;
        }
        else {
            index = 0;
        }
        if (enter_func) enter_func(widgets[index]);
        widgets[index]->update();
    }
    void roll_left() {
        if (widgets.empty()) return;
        if (leave_func) leave_func(widgets[index]);
        widgets[index]->update();
        if (widgets.front() != widgets[index]) {
            index--;
        }
        else {
            index = static_cast<int>(widgets.size()) - 1;
        }
        if (enter_func) enter_func(widgets[index]);
        widgets[index]->update();
    }
    QHBoxLayout* hbox_layout(int space) {
        auto ret = new QHBoxLayout;
        ret->setMargin(0);
        ret->setSpacing(space);
        for (auto widget : widgets) {
            ret->addWidget(widget, 1);
        }
        return ret;
    }
};
}
#endif