#pragma once

#include <map>
#include <vector>
#include <algorithm>

class SelectionManager
{
public:
    explicit SelectionManager() :
        _multiselection_enabled(false)
    {}

    void discard()
    {
        _selected_ids.clear();
    }

    void fetch(int note_id, int element_id)
    {
        if (!isSelected(note_id, element_id))
            _selected_ids[note_id].emplace_back(element_id);
    }

    void remove(int note_id, int element_id)
    {
        if (_selected_ids.count(note_id) == 0)
            return;

        auto& elements_ids = _selected_ids[note_id];

        for (std::size_t i = 0; i < elements_ids.size(); ++i)
        {
            if (element_id == elements_ids.at(i))
            {
                elements_ids[i] = std::move(elements_ids.back());
                elements_ids.pop_back();
                break;
            }
        }
    }

    bool isSelected(int note_id, int element_id) const
    {
        if (_selected_ids.count(note_id) == 0)
            return false;

        const std::vector<int>& selected_elements = _selected_ids.at(note_id);
        for (const auto& selected_element : selected_elements)
            if (selected_element == element_id)
                return true;

        return false;
    }

    void enableMultiselection(bool enable = true)
    {
        _multiselection_enabled = enable;
    }

    bool isMultiselectionEnabled() const
    {
        return _multiselection_enabled;
    }

private:
    std::map<int, std::vector<int>> _selected_ids;
    bool _multiselection_enabled;
};