event_loop.hpp

#ifndef TERMOX_SYSTEM_EVENT_LOOP_HPP
#define TERMOX_SYSTEM_EVENT_LOOP_HPP
#include <atomic>
#include <cassert>
#include <future>
#include <utility>
 
#include <termox/system/event_queue.hpp>
 
namespace ox {
 
 
class Event_loop {
   public:
 
    template <typename F>
    auto run(F loop_function) -> int
    {
        if (running_)
            return -1;
        running_ = true;
        if (!exit_)
            queue_.send_all();
        while (!exit_) {
            loop_function(queue_);
            queue_.send_all();
        }
        running_ = false;
        exit_    = false;
        return return_code_;
    }
 
 
    template <typename F>
    void run_async(F&& loop_function)
    {
        if (fut_.valid())
            return;
        fut_ = std::async(std::launch::async, [this, loop_function] {
            return this->run(std::move(loop_function));
        });
        assert(fut_.valid());
    }
 
 
    void exit(int return_code);
 
 
    // wait, then if valid, get it
    auto wait() -> int;
 
    [[nodiscard]] auto is_running() const -> bool;
 
    [[nodiscard]] auto exit_flag() const -> bool;
 
    [[nodiscard]] auto event_queue() -> Event_queue&;
 
    [[nodiscard]] auto event_queue() const -> Event_queue const&;
 
   private:
    std::future<int> fut_;
    int return_code_           = 0;
    std::atomic<bool> running_ = false;
    std::atomic<bool> exit_    = false;
    Event_queue queue_;
};
 
}  // namespace ox
#endif  // TERMOX_SYSTEM_EVENT_LOOP_HPP