asyncpp/include/asyncpp/fs/directory/read_all.inl

#pragma once

#include <vector>

#include <cppfs/directory.h>

#include "directory.h"

namespace asyncpp {
namespace fs {
namespace __directory {

    struct read_all_stream
        : public base_stream<
            cppfs::directory::entry,
            read_all_stream>
    {
    public:
        using value_type        = cppfs::directory::entry;
        using this_type         = read_all_stream;
        using base_future_type  = base_stream<value_type, this_type>;
        using result_type       = typename base_future_type::result_type;

    private:
        struct entry
        {
            cppfs::directory::iterator  it;
            cppfs::directory::iterator  end;
        };

        using entry_stack = std::vector<entry>;

        entry_stack _stack;

    public:
        inline read_all_stream(
            const fs::directory& p_directory)
        {
            auto& d = p_directory.handle;
            if (d.exists())
            {
                _stack.emplace_back(entry {
                    d.begin(),
                    d.end()
                });
            }
        }

    public:
        inline result_type poll()
        {
            while (true)
            {
                if (_stack.empty())
                    return result_type::done();

                auto& e = _stack.back();
                if (e.it == e.end)
                {
                    _stack.pop_back();
                    continue;
                }

                auto ret = result_type::ready(std::move(*e.it));
                cppfs::directory d(e.it->path);

                ++e.it;

                if (d.exists())
                {
                    _stack.emplace_back(entry {
                        d.begin(),
                        d.end(),
                    });
                }

                return ret;
            }
        }
    };

    template<
        chaining_mode X_mode,
        typename X_self>
    inline auto read_all_impl(X_self&& p_self)
        { return read_all_stream(std::forward<X_self>(p_self)); }

} } }

namespace asyncpp {
namespace fs {

    template<chaining_mode X_mode>
    auto directory
        ::read_all() &
    {
        return __directory::read_all_impl<X_mode>(*this);
    }

    template<chaining_mode X_mode>
    auto directory
        ::read_all() &&
    {
        static_assert(
            X_mode != ref,
            "Can not store rvalue reference as lvalue reference!");

        return __directory::read_all_impl<X_mode>(std::move(*this));
    }

} }