#include <sys/socket.h>
#include <sys/epoll.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include "osd_ops.h"
#include "ringloop.h"

class osd_t
{
    int wait_state = 0;
    int epoll_fd = 0;
    int listen_fd = 0;
    ring_consumer_t consumer;

    std::string bind_address;
    int bind_port, listen_backlog;
    ring_loop_t *ringloop;

    void handle_epoll_events();
public:
    osd_t(ring_loop_t *ringloop);
    ~osd_t();
    void loop();
};

class osd_client_t
{
    int sock_fd;
};

osd_t::osd_t(ring_loop_t *ringloop)
{
    this->ringloop = ringloop;

    listen_fd = socket(AF_INET, SOCK_STREAM, 0);
    if (listen_fd < 0)
    {
        throw std::runtime_error(std::string("socket: ") + strerror(errno));
    }

    sockaddr_in addr;
    if ((int r = inet_pton(AF_INET, bind_address.c_str(), &addr.sin_addr)) != 1)
    {
        close(listen_fd);
        throw std::runtime_error("bind address "+bind_address+(r == 0 ? " is not valid" : ": no ipv4 support"));
    }
    addr.sin_family = AF_INET;
    addr.sin_port = bind_port;

    if (bind(listen_fd, &addr, sizeof(addr)) < 0)
    {
        close(listen_fd);
        throw std::runtime_error(std::string("bind: ") + strerror(errno));
    }

    if (listen(listen_fd, listen_backlog) < 0)
    {
        close(listen_fd);
        throw std::runtime_error(std::string("listen: ") + strerror(errno));
    }

    epoll_fd = epoll_create(1);
    if (epoll_fd < 0)
    {
        close(listen_fd);
        throw std::runtime_error(std::string("epoll_create: ") + strerror(errno));
    }

    struct epoll_event ev;
    ev.data.fd = listen_fd;
    ev.events = EPOLLIN | EPOLLET | EPOLLONESHOT;
    if (epoll_ctl(epfd, EPOLL_CTL_ADD, sfd, &ev) < 0)
    {
        throw std::runtime_error(std::string("epoll_ctl: ") + strerror(errno));
    }

    consumer.loop = [this]() { loop(); };
    ringloop->register_consumer(consumer);
}

osd_t::~osd_t()
{
    ringloop->unregister_consumer(consumer);
    close(epoll_fd);
    close(listen_fd);
}

void osd_t::loop()
{
    if (wait_state == 1)
    {
        return;
    }
    struct io_uring_sqe *sqe = ringloop->get_sqe();
    if (!sqe)
    {
        wait_state = 0;
        return;
    }
    struct ring_data_t *data = ((ring_data_t*)sqe->user_data);
    my_uring_prep_poll_add(sqe, epoll_fd, POLLIN);
    data->callback = [&](ring_data_t *data)
    {
        if (data->res < 0)
        {
            throw std::runtime_error(std::string("epoll failed: ") + strerror(-data->res));
        }
        handle_epoll_events();
        wait_state = 0;
    };
    wait_state = 1;
    ringloop->submit();
}

void osd_t::handle_epoll_events()
{
    
}