mutable_cell_view.hpp

/*
 * live_cells_cpp
 * Copyright (C) 2024  Alexander Gutev <alex.gutev@gmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you
 * may not use this file except in compliance with the License.  You
 * may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied.  See the License for the specific language governing
 * permissions and limitations under the License.
 */
 
#ifndef LIVE_CELLS_MUTABLE_CELL_VIEW_HPP
#define LIVE_CELLS_MUTABLE_CELL_VIEW_HPP
 
#include <functional>
#include <tuple>
#include <utility>
 
#include "make_cell.hpp"
#include "compute_cell.hpp"
#include "mutable_cell.hpp"
 
namespace live_cells {
    template <std::invocable F, typename R, typename... Os>
    class mutable_cell_view_base : public compute_cell_base<F, Os...> {
 
        typedef compute_cell_base<F, Os...> parent;
 
        typedef std::invoke_result_t<F> value_type;
 
    public:
        using parent::value;
 
        mutable_cell_view_base(F compute, R reverse, Os... args) :
            parent(compute, args...),
            reverse(reverse) {}
 
        void value(value_type value) const {
            batch([&] {
                reverse(value);
            });
        }
 
    private:
        const R reverse;
    };
 
    template <std::invocable F, typename R, Cell... Ts>
    using mutable_cell_view = make_mutable_cell<mutable_cell_view_base<F,R,Ts...>>;
 
    auto make_mutable_cell_view(std::invocable auto compute, auto reverse, auto... args) {
        return mutable_cell_view<
            decltype(compute),
            decltype(reverse),
            decltype(args)...>(
                compute,
                reverse,
                args...
        );
    }
 
    auto make_mutable_cell_view(key_ref key, std::invocable auto compute, auto reverse, auto... args) {
        return mutable_cell_view<
            decltype(compute),
            decltype(reverse),
            decltype(args)...>(
                key,
                compute,
                reverse,
                args...
        );
    }
 
    template <typename A1, typename A2, typename... As>
    auto cell_view(key_ref key, A1 arg1, A2 arg2, As... args) {
        auto packed = internal::pack<2>(arg1, arg2, args...);
 
        auto fn_args = std::get<0>(packed);
        auto compute = std::get<1>(packed);
        auto reverse = std::get<2>(packed);
 
        return std::apply([&] (auto... args) {
            auto f = [=] {
                return compute(args.value()...);
            };
 
            return make_mutable_cell_view(key, f, reverse, args...);
        }, fn_args);
    }
 
    template <typename A1, typename A2, typename... As>
    auto cell_view(A1 arg1, A2 arg2, As... args) {
        auto packed = internal::pack<2>(arg1, arg2, args...);
 
        auto fn_args = std::get<0>(packed);
        auto compute = std::get<1>(packed);
        auto reverse = std::get<2>(packed);
 
        return std::apply([&] (auto... args) {
            auto f = [=] {
                return compute(args.value()...);
            };
 
            return make_mutable_cell_view(f, reverse, args...);
        }, fn_args);
    }
 
}  // live_cells
 
 
#endif /* LIVE_CELLS_MUTABLE_CELL_VIEW_HPP */