// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#include <algorithm>
#include <cstring>
#include <unordered_map>
#include <vector>
#include "common/assert.h"
#include "common/bit_field.h"
#include "common/common_types.h"
#include "common/logging/log.h"
#include "common/scope_exit.h"
#include "core/hle/ipc.h"
#include "core/hle/kernel/server_session.h"
#include "core/hle/result.h"
#include "core/hle/service/soc_u.h"
#include "core/memory.h"

#ifdef _WIN32
#include <winsock2.h>
#include <ws2tcpip.h>

// MinGW does not define several errno constants
#ifndef _MSC_VER
#define EBADMSG 104
#define ENODATA 120
#define ENOMSG 122
#define ENOSR 124
#define ENOSTR 125
#define ETIME 137
#endif // _MSC_VER
#else
#include <cerrno>
#include <fcntl.h>
#include <netdb.h>
#include <netinet/in.h>
#include <poll.h>
#include <sys/socket.h>
#include <unistd.h>
#endif

#ifdef _WIN32
#define WSAEAGAIN WSAEWOULDBLOCK
#define WSAEMULTIHOP -1 // Invalid dummy value
#define ERRNO(x) WSA##x
#define GET_ERRNO WSAGetLastError()
#define poll(x, y, z) WSAPoll(x, y, z);
#else
#define ERRNO(x) x
#define GET_ERRNO errno
#define closesocket(x) close(x)
#endif

namespace Service {
namespace SOC {

const s32 SOCKET_ERROR_VALUE = -1;

/// Holds the translation from system network errors to 3DS network errors
static const std::unordered_map<int, int> error_map = {{
    {E2BIG, 1},
    {ERRNO(EACCES), 2},
    {ERRNO(EADDRINUSE), 3},
    {ERRNO(EADDRNOTAVAIL), 4},
    {ERRNO(EAFNOSUPPORT), 5},
    {ERRNO(EAGAIN), 6},
    {ERRNO(EALREADY), 7},
    {ERRNO(EBADF), 8},
    {EBADMSG, 9},
    {EBUSY, 10},
    {ECANCELED, 11},
    {ECHILD, 12},
    {ERRNO(ECONNABORTED), 13},
    {ERRNO(ECONNREFUSED), 14},
    {ERRNO(ECONNRESET), 15},
    {EDEADLK, 16},
    {ERRNO(EDESTADDRREQ), 17},
    {EDOM, 18},
    {ERRNO(EDQUOT), 19},
    {EEXIST, 20},
    {ERRNO(EFAULT), 21},
    {EFBIG, 22},
    {ERRNO(EHOSTUNREACH), 23},
    {EIDRM, 24},
    {EILSEQ, 25},
    {ERRNO(EINPROGRESS), 26},
    {ERRNO(EINTR), 27},
    {ERRNO(EINVAL), 28},
    {EIO, 29},
    {ERRNO(EISCONN), 30},
    {EISDIR, 31},
    {ERRNO(ELOOP), 32},
    {ERRNO(EMFILE), 33},
    {EMLINK, 34},
    {ERRNO(EMSGSIZE), 35},
    {ERRNO(EMULTIHOP), 36},
    {ERRNO(ENAMETOOLONG), 37},
    {ERRNO(ENETDOWN), 38},
    {ERRNO(ENETRESET), 39},
    {ERRNO(ENETUNREACH), 40},
    {ENFILE, 41},
    {ERRNO(ENOBUFS), 42},
#ifdef ENODATA
    {ENODATA, 43},
#endif
    {ENODEV, 44},
    {ENOENT, 45},
    {ENOEXEC, 46},
    {ENOLCK, 47},
    {ENOLINK, 48},
    {ENOMEM, 49},
    {ENOMSG, 50},
    {ERRNO(ENOPROTOOPT), 51},
    {ENOSPC, 52},
#ifdef ENOSR
    {ENOSR, 53},
#endif
#ifdef ENOSTR
    {ENOSTR, 54},
#endif
    {ENOSYS, 55},
    {ERRNO(ENOTCONN), 56},
    {ENOTDIR, 57},
    {ERRNO(ENOTEMPTY), 58},
    {ERRNO(ENOTSOCK), 59},
    {ENOTSUP, 60},
    {ENOTTY, 61},
    {ENXIO, 62},
    {ERRNO(EOPNOTSUPP), 63},
    {EOVERFLOW, 64},
    {EPERM, 65},
    {EPIPE, 66},
    {EPROTO, 67},
    {ERRNO(EPROTONOSUPPORT), 68},
    {ERRNO(EPROTOTYPE), 69},
    {ERANGE, 70},
    {EROFS, 71},
    {ESPIPE, 72},
    {ESRCH, 73},
    {ERRNO(ESTALE), 74},
#ifdef ETIME
    {ETIME, 75},
#endif
    {ERRNO(ETIMEDOUT), 76},
}};

/// Converts a network error from platform-specific to 3ds-specific
static int TranslateError(int error) {
    auto found = error_map.find(error);
    if (found != error_map.end())
        return -found->second;

    return error;
}

/// Holds the translation from system network socket options to 3DS network socket options
/// Note: -1 = No effect/unavailable
static const std::unordered_map<int, int> sockopt_map = {{
    {0x0004, SO_REUSEADDR},
    {0x0080, -1},
    {0x0100, -1},
    {0x1001, SO_SNDBUF},
    {0x1002, SO_RCVBUF},
    {0x1003, -1},
#ifdef _WIN32
    /// Unsupported in WinSock2
    {0x1004, -1},
#else
    {0x1004, SO_RCVLOWAT},
#endif
    {0x1008, SO_TYPE},
    {0x1009, SO_ERROR},
}};

/// Converts a socket option from 3ds-specific to platform-specific
static int TranslateSockOpt(int console_opt_name) {
    auto found = sockopt_map.find(console_opt_name);
    if (found != sockopt_map.end()) {
        return found->second;
    }
    return console_opt_name;
}

/// Holds information about a particular socket
struct SocketHolder {
    u32 socket_fd; ///< The socket descriptor
    bool blocking; ///< Whether the socket is blocking or not, it is only read on Windows.
};

/// Structure to represent the 3ds' pollfd structure, which is different than most implementations
struct CTRPollFD {
    u32 fd; ///< Socket handle

    union Events {
        u32 hex; ///< The complete value formed by the flags
        BitField<0, 1, u32> pollin;
        BitField<1, 1, u32> pollpri;
        BitField<2, 1, u32> pollhup;
        BitField<3, 1, u32> pollerr;
        BitField<4, 1, u32> pollout;
        BitField<5, 1, u32> pollnval;

        Events& operator=(const Events& other) {
            hex = other.hex;
            return *this;
        }

        /// Translates the resulting events of a Poll operation from platform-specific to 3ds
        /// specific
        static Events TranslateTo3DS(u32 input_event) {
            Events ev = {};
            if (input_event & POLLIN)
                ev.pollin.Assign(1);
            if (input_event & POLLPRI)
                ev.pollpri.Assign(1);
            if (input_event & POLLHUP)
                ev.pollhup.Assign(1);
            if (input_event & POLLERR)
                ev.pollerr.Assign(1);
            if (input_event & POLLOUT)
                ev.pollout.Assign(1);
            if (input_event & POLLNVAL)
                ev.pollnval.Assign(1);
            return ev;
        }

        /// Translates the resulting events of a Poll operation from 3ds specific to platform
        /// specific
        static u32 TranslateToPlatform(Events input_event) {
            u32 ret = 0;
            if (input_event.pollin)
                ret |= POLLIN;
            if (input_event.pollpri)
                ret |= POLLPRI;
            if (input_event.pollhup)
                ret |= POLLHUP;
            if (input_event.pollerr)
                ret |= POLLERR;
            if (input_event.pollout)
                ret |= POLLOUT;
            if (input_event.pollnval)
                ret |= POLLNVAL;
            return ret;
        }
    };
    Events events;  ///< Events to poll for (input)
    Events revents; ///< Events received (output)

    /// Converts a platform-specific pollfd to a 3ds specific structure
    static CTRPollFD FromPlatform(pollfd const& fd) {
        CTRPollFD result;
        result.events.hex = Events::TranslateTo3DS(fd.events).hex;
        result.revents.hex = Events::TranslateTo3DS(fd.revents).hex;
        result.fd = static_cast<u32>(fd.fd);
        return result;
    }

    /// Converts a 3ds specific pollfd to a platform-specific structure
    static pollfd ToPlatform(CTRPollFD const& fd) {
        pollfd result;
        result.events = Events::TranslateToPlatform(fd.events);
        result.revents = Events::TranslateToPlatform(fd.revents);
        result.fd = fd.fd;
        return result;
    }
};

/// Union to represent the 3ds' sockaddr structure
union CTRSockAddr {
    /// Structure to represent a raw sockaddr
    struct {
        u8 len;           ///< The length of the entire structure, only the set fields count
        u8 sa_family;     ///< The address family of the sockaddr
        u8 sa_data[0x1A]; ///< The extra data, this varies, depending on the address family
    } raw;

    /// Structure to represent the 3ds' sockaddr_in structure
    struct CTRSockAddrIn {
        u8 len;        ///< The length of the entire structure
        u8 sin_family; ///< The address family of the sockaddr_in
        u16 sin_port;  ///< The port associated with this sockaddr_in
        u32 sin_addr;  ///< The actual address of the sockaddr_in
    } in;

    /// Convert a 3DS CTRSockAddr to a platform-specific sockaddr
    static sockaddr ToPlatform(CTRSockAddr const& ctr_addr) {
        sockaddr result;
        result.sa_family = ctr_addr.raw.sa_family;
        memset(result.sa_data, 0, sizeof(result.sa_data));

        // We can not guarantee ABI compatibility between platforms so we copy the fields manually
        switch (result.sa_family) {
        case AF_INET: {
            sockaddr_in* result_in = reinterpret_cast<sockaddr_in*>(&result);
            result_in->sin_port = ctr_addr.in.sin_port;
            result_in->sin_addr.s_addr = ctr_addr.in.sin_addr;
            memset(result_in->sin_zero, 0, sizeof(result_in->sin_zero));
            break;
        }
        default:
            ASSERT_MSG(false, "Unhandled address family (sa_family) in CTRSockAddr::ToPlatform");
            break;
        }
        return result;
    }

    /// Convert a platform-specific sockaddr to a 3DS CTRSockAddr
    static CTRSockAddr FromPlatform(sockaddr const& addr) {
        CTRSockAddr result;
        result.raw.sa_family = static_cast<u8>(addr.sa_family);
        // We can not guarantee ABI compatibility between platforms so we copy the fields manually
        switch (result.raw.sa_family) {
        case AF_INET: {
            sockaddr_in const* addr_in = reinterpret_cast<sockaddr_in const*>(&addr);
            result.raw.len = sizeof(CTRSockAddrIn);
            result.in.sin_port = addr_in->sin_port;
            result.in.sin_addr = addr_in->sin_addr.s_addr;
            break;
        }
        default:
            ASSERT_MSG(false, "Unhandled address family (sa_family) in CTRSockAddr::ToPlatform");
            break;
        }
        return result;
    }
};

/// Holds info about the currently open sockets
static std::unordered_map<u32, SocketHolder> open_sockets;

/// Close all open sockets
static void CleanupSockets() {
    for (auto sock : open_sockets)
        closesocket(sock.second.socket_fd);
    open_sockets.clear();
}

static void Socket(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 domain = cmd_buffer[1]; // Address family
    u32 type = cmd_buffer[2];
    u32 protocol = cmd_buffer[3];

    // Only 0 is allowed according to 3dbrew, using 0 will let the OS decide which protocol to use
    if (protocol != 0) {
        cmd_buffer[1] =
            UnimplementedFunction(ErrorModule::SOC).raw; // TODO(Subv): Correct error code
        return;
    }

    if (domain != AF_INET) {
        cmd_buffer[1] =
            UnimplementedFunction(ErrorModule::SOC).raw; // TODO(Subv): Correct error code
        return;
    }

    if (type != SOCK_DGRAM && type != SOCK_STREAM) {
        cmd_buffer[1] =
            UnimplementedFunction(ErrorModule::SOC).raw; // TODO(Subv): Correct error code
        return;
    }

    u32 ret = static_cast<u32>(::socket(domain, type, protocol));

    if ((s32)ret != SOCKET_ERROR_VALUE)
        open_sockets[ret] = {ret, true};

    int result = 0;
    if ((s32)ret == SOCKET_ERROR_VALUE)
        ret = TranslateError(GET_ERRNO);

    cmd_buffer[0] = IPC::MakeHeader(2, 2, 0);
    cmd_buffer[1] = result;
    cmd_buffer[2] = ret;
}

static void Bind(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];
    u32 len = cmd_buffer[2];

    // Virtual address of the sock_addr structure
    VAddr sock_addr_addr = cmd_buffer[6];
    if (!Memory::IsValidVirtualAddress(sock_addr_addr)) {
        cmd_buffer[1] = -1; // TODO(Subv): Correct code
        return;
    }

    CTRSockAddr ctr_sock_addr;
    Memory::ReadBlock(sock_addr_addr, reinterpret_cast<u8*>(&ctr_sock_addr), sizeof(CTRSockAddr));

    sockaddr sock_addr = CTRSockAddr::ToPlatform(ctr_sock_addr);

    int ret = ::bind(socket_handle, &sock_addr, std::max<u32>(sizeof(sock_addr), len));

    int result = 0;
    if (ret != 0)
        ret = TranslateError(GET_ERRNO);

    cmd_buffer[0] = IPC::MakeHeader(5, 2, 0);
    cmd_buffer[1] = result;
    cmd_buffer[2] = ret;
}

static void Fcntl(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];
    u32 ctr_cmd = cmd_buffer[2];
    u32 ctr_arg = cmd_buffer[3];

    int result = 0;
    u32 posix_ret = 0; // TODO: Check what hardware returns for F_SETFL (unspecified by POSIX)
    SCOPE_EXIT({
        cmd_buffer[1] = result;
        cmd_buffer[2] = posix_ret;
    });

    if (ctr_cmd == 3) { // F_GETFL
#ifdef _WIN32
        posix_ret = 0;
        auto iter = open_sockets.find(socket_handle);
        if (iter != open_sockets.end() && iter->second.blocking == false)
            posix_ret |= 4; // O_NONBLOCK
#else
        int ret = ::fcntl(socket_handle, F_GETFL, 0);
        if (ret == SOCKET_ERROR_VALUE) {
            posix_ret = TranslateError(GET_ERRNO);
            return;
        }
        posix_ret = 0;
        if (ret & O_NONBLOCK)
            posix_ret |= 4; // O_NONBLOCK
#endif
    } else if (ctr_cmd == 4) { // F_SETFL
#ifdef _WIN32
        unsigned long tmp = (ctr_arg & 4 /* O_NONBLOCK */) ? 1 : 0;
        int ret = ioctlsocket(socket_handle, FIONBIO, &tmp);
        if (ret == SOCKET_ERROR_VALUE) {
            posix_ret = TranslateError(GET_ERRNO);
            return;
        }
        auto iter = open_sockets.find(socket_handle);
        if (iter != open_sockets.end())
            iter->second.blocking = (tmp == 0);
#else
        int flags = ::fcntl(socket_handle, F_GETFL, 0);
        if (flags == SOCKET_ERROR_VALUE) {
            posix_ret = TranslateError(GET_ERRNO);
            return;
        }

        flags &= ~O_NONBLOCK;
        if (ctr_arg & 4) // O_NONBLOCK
            flags |= O_NONBLOCK;

        int ret = ::fcntl(socket_handle, F_SETFL, flags);
        if (ret == SOCKET_ERROR_VALUE) {
            posix_ret = TranslateError(GET_ERRNO);
            return;
        }
#endif
    } else {
        LOG_ERROR(Service_SOC, "Unsupported command (%d) in fcntl call", ctr_cmd);
        posix_ret = TranslateError(EINVAL); // TODO: Find the correct error
        return;
    }
}

static void Listen(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];
    u32 backlog = cmd_buffer[2];

    int ret = ::listen(socket_handle, backlog);
    int result = 0;
    if (ret != 0)
        ret = TranslateError(GET_ERRNO);

    cmd_buffer[0] = IPC::MakeHeader(3, 2, 0);
    cmd_buffer[1] = result;
    cmd_buffer[2] = ret;
}

static void Accept(Interface* self) {
    // TODO(Subv): Calling this function on a blocking socket will block the emu thread,
    // preventing graceful shutdown when closing the emulator, this can be fixed by always
    // performing nonblocking operations and spinlock until the data is available
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];
    socklen_t max_addr_len = static_cast<socklen_t>(cmd_buffer[2]);
    sockaddr addr;
    socklen_t addr_len = sizeof(addr);
    u32 ret = static_cast<u32>(::accept(socket_handle, &addr, &addr_len));

    if ((s32)ret != SOCKET_ERROR_VALUE)
        open_sockets[ret] = {ret, true};

    int result = 0;
    if ((s32)ret == SOCKET_ERROR_VALUE) {
        ret = TranslateError(GET_ERRNO);
    } else {
        CTRSockAddr ctr_addr = CTRSockAddr::FromPlatform(addr);
        Memory::WriteBlock(cmd_buffer[0x104 >> 2], &ctr_addr, sizeof(ctr_addr));
    }

    cmd_buffer[0] = IPC::MakeHeader(4, 2, 2);
    cmd_buffer[1] = result;
    cmd_buffer[2] = ret;
    cmd_buffer[3] = IPC::StaticBufferDesc(static_cast<u32>(max_addr_len), 0);
}

static void GetHostId(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();

    char name[128];
    gethostname(name, sizeof(name));
    addrinfo hints = {};
    addrinfo* res;

    hints.ai_family = AF_INET;
    getaddrinfo(name, nullptr, &hints, &res);
    sockaddr_in* sock_addr = reinterpret_cast<sockaddr_in*>(res->ai_addr);
    in_addr* addr = &sock_addr->sin_addr;

    cmd_buffer[2] = addr->s_addr;
    cmd_buffer[1] = 0;
    freeaddrinfo(res);
}

static void Close(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];

    int ret = 0;
    open_sockets.erase(socket_handle);

    ret = closesocket(socket_handle);

    int result = 0;
    if (ret != 0)
        ret = TranslateError(GET_ERRNO);

    cmd_buffer[2] = ret;
    cmd_buffer[1] = result;
}

static void SendTo(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];
    u32 len = cmd_buffer[2];
    u32 flags = cmd_buffer[3];
    u32 addr_len = cmd_buffer[4];

    VAddr input_buff_address = cmd_buffer[8];
    if (!Memory::IsValidVirtualAddress(input_buff_address)) {
        cmd_buffer[1] = -1; // TODO(Subv): Find the right error code
        return;
    }

    // Memory address of the dest_addr structure
    VAddr dest_addr_addr = cmd_buffer[10];
    if (!Memory::IsValidVirtualAddress(dest_addr_addr)) {
        cmd_buffer[1] = -1; // TODO(Subv): Find the right error code
        return;
    }

    std::vector<u8> input_buff(len);
    Memory::ReadBlock(input_buff_address, input_buff.data(), input_buff.size());

    CTRSockAddr ctr_dest_addr;
    Memory::ReadBlock(dest_addr_addr, &ctr_dest_addr, sizeof(ctr_dest_addr));

    int ret = -1;
    if (addr_len > 0) {
        sockaddr dest_addr = CTRSockAddr::ToPlatform(ctr_dest_addr);
        ret = ::sendto(socket_handle, reinterpret_cast<const char*>(input_buff.data()), len, flags,
                       &dest_addr, sizeof(dest_addr));
    } else {
        ret = ::sendto(socket_handle, reinterpret_cast<const char*>(input_buff.data()), len, flags,
                       nullptr, 0);
    }

    int result = 0;
    if (ret == SOCKET_ERROR_VALUE)
        ret = TranslateError(GET_ERRNO);

    cmd_buffer[2] = ret;
    cmd_buffer[1] = result;
}

static void RecvFrom(Interface* self) {
    // TODO(Subv): Calling this function on a blocking socket will block the emu thread,
    // preventing graceful shutdown when closing the emulator, this can be fixed by always
    // performing nonblocking operations and spinlock until the data is available
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];
    u32 len = cmd_buffer[2];
    u32 flags = cmd_buffer[3];

    struct {
        u32 output_buffer_descriptor;
        u32 output_buffer_addr;
        u32 address_buffer_descriptor;
        u32 output_src_address_buffer;
    } buffer_parameters;

    std::memcpy(&buffer_parameters, &cmd_buffer[64], sizeof(buffer_parameters));

    if (!Memory::IsValidVirtualAddress(buffer_parameters.output_buffer_addr)) {
        cmd_buffer[1] = -1; // TODO(Subv): Find the right error code
        return;
    }

    if (!Memory::IsValidVirtualAddress(buffer_parameters.output_src_address_buffer)) {
        cmd_buffer[1] = -1; // TODO(Subv): Find the right error code
        return;
    }

    std::vector<u8> output_buff(len);
    sockaddr src_addr;
    socklen_t src_addr_len = sizeof(src_addr);
    int ret = ::recvfrom(socket_handle, reinterpret_cast<char*>(output_buff.data()), len, flags,
                         &src_addr, &src_addr_len);

    if (ret >= 0 && buffer_parameters.output_src_address_buffer != 0 && src_addr_len > 0) {
        CTRSockAddr ctr_src_addr = CTRSockAddr::FromPlatform(src_addr);
        Memory::WriteBlock(buffer_parameters.output_src_address_buffer, &ctr_src_addr,
                           sizeof(ctr_src_addr));
    }

    int result = 0;
    int total_received = ret;
    if (ret == SOCKET_ERROR_VALUE) {
        ret = TranslateError(GET_ERRNO);
        total_received = 0;
    } else {
        // Write only the data we received to avoid overwriting parts of the buffer with zeros
        Memory::WriteBlock(buffer_parameters.output_buffer_addr, output_buff.data(),
                           total_received);
    }

    cmd_buffer[1] = result;
    cmd_buffer[2] = ret;
    cmd_buffer[3] = total_received;
}

static void Poll(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 nfds = cmd_buffer[1];
    int timeout = cmd_buffer[2];

    VAddr input_fds_addr = cmd_buffer[6];
    VAddr output_fds_addr = cmd_buffer[0x104 >> 2];
    if (!Memory::IsValidVirtualAddress(input_fds_addr) ||
        !Memory::IsValidVirtualAddress(output_fds_addr)) {
        cmd_buffer[1] = -1; // TODO(Subv): Find correct error code.
        return;
    }

    std::vector<CTRPollFD> ctr_fds(nfds);
    Memory::ReadBlock(input_fds_addr, ctr_fds.data(), nfds * sizeof(CTRPollFD));

    // The 3ds_pollfd and the pollfd structures may be different (Windows/Linux have different
    // sizes)
    // so we have to copy the data
    std::vector<pollfd> platform_pollfd(nfds);
    std::transform(ctr_fds.begin(), ctr_fds.end(), platform_pollfd.begin(), CTRPollFD::ToPlatform);

    int ret = ::poll(platform_pollfd.data(), nfds, timeout);

    // Now update the output pollfd structure
    std::transform(platform_pollfd.begin(), platform_pollfd.end(), ctr_fds.begin(),
                   CTRPollFD::FromPlatform);

    Memory::WriteBlock(output_fds_addr, ctr_fds.data(), nfds * sizeof(CTRPollFD));

    int result = 0;
    if (ret == SOCKET_ERROR_VALUE)
        ret = TranslateError(GET_ERRNO);

    cmd_buffer[1] = result;
    cmd_buffer[2] = ret;
}

static void GetSockName(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];

    // Memory address of the ctr_dest_addr structure
    VAddr ctr_dest_addr_addr = cmd_buffer[0x104 >> 2];

    sockaddr dest_addr;
    socklen_t dest_addr_len = sizeof(dest_addr);
    int ret = ::getsockname(socket_handle, &dest_addr, &dest_addr_len);

    if (ctr_dest_addr_addr != 0 && Memory::IsValidVirtualAddress(ctr_dest_addr_addr)) {
        CTRSockAddr ctr_dest_addr = CTRSockAddr::FromPlatform(dest_addr);
        Memory::WriteBlock(ctr_dest_addr_addr, &ctr_dest_addr, sizeof(ctr_dest_addr));
    } else {
        cmd_buffer[1] = -1; // TODO(Subv): Verify error
        return;
    }

    int result = 0;
    if (ret != 0)
        ret = TranslateError(GET_ERRNO);

    cmd_buffer[2] = ret;
    cmd_buffer[1] = result;
}

static void Shutdown(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];
    int how = cmd_buffer[2];

    int ret = ::shutdown(socket_handle, how);
    int result = 0;
    if (ret != 0)
        ret = TranslateError(GET_ERRNO);
    cmd_buffer[2] = ret;
    cmd_buffer[1] = result;
}

static void GetPeerName(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];

    // Memory address of the ctr_dest_addr structure
    VAddr ctr_dest_addr_addr = cmd_buffer[0x104 >> 2];

    sockaddr dest_addr;
    socklen_t dest_addr_len = sizeof(dest_addr);
    int ret = ::getpeername(socket_handle, &dest_addr, &dest_addr_len);

    if (ctr_dest_addr_addr != 0 && Memory::IsValidVirtualAddress(ctr_dest_addr_addr)) {
        CTRSockAddr ctr_dest_addr = CTRSockAddr::FromPlatform(dest_addr);
        Memory::WriteBlock(ctr_dest_addr_addr, &ctr_dest_addr, sizeof(ctr_dest_addr));
    } else {
        cmd_buffer[1] = -1;
        return;
    }

    int result = 0;
    if (ret != 0)
        ret = TranslateError(GET_ERRNO);

    cmd_buffer[2] = ret;
    cmd_buffer[1] = result;
}

static void Connect(Interface* self) {
    // TODO(Subv): Calling this function on a blocking socket will block the emu thread,
    // preventing graceful shutdown when closing the emulator, this can be fixed by always
    // performing nonblocking operations and spinlock until the data is available
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];

    // Memory address of the ctr_input_addr structure
    VAddr ctr_input_addr_addr = cmd_buffer[6];
    if (!Memory::IsValidVirtualAddress(ctr_input_addr_addr)) {
        cmd_buffer[1] = -1; // TODO(Subv): Verify error
        return;
    }

    CTRSockAddr ctr_input_addr;
    Memory::ReadBlock(ctr_input_addr_addr, &ctr_input_addr, sizeof(ctr_input_addr));

    sockaddr input_addr = CTRSockAddr::ToPlatform(ctr_input_addr);
    int ret = ::connect(socket_handle, &input_addr, sizeof(input_addr));
    int result = 0;
    if (ret != 0)
        ret = TranslateError(GET_ERRNO);

    cmd_buffer[0] = IPC::MakeHeader(6, 2, 0);
    cmd_buffer[1] = result;
    cmd_buffer[2] = ret;
}

static void InitializeSockets(Interface* self) {
// TODO(Subv): Implement
#ifdef _WIN32
    WSADATA data;
    WSAStartup(MAKEWORD(2, 2), &data);
#endif

    u32* cmd_buffer = Kernel::GetCommandBuffer();
    cmd_buffer[0] = IPC::MakeHeader(1, 1, 0);
    cmd_buffer[1] = RESULT_SUCCESS.raw;
}

static void ShutdownSockets(Interface* self) {
    // TODO(Subv): Implement
    CleanupSockets();

    u32* cmd_buffer = Kernel::GetCommandBuffer();
    cmd_buffer[1] = 0;
}

static void GetSockOpt(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];
    u32 level = cmd_buffer[2];
    int optname = TranslateSockOpt(cmd_buffer[3]);
    socklen_t optlen = (socklen_t)cmd_buffer[4];

    int ret = 0;
    int err = 0;

    if (optname < 0) {
#ifdef _WIN32
        err = WSAEINVAL;
#else
        err = EINVAL;
#endif
    } else {
        // 0x100 = static buffer offset (bytes)
        // + 0x4 = 2nd pointer (u32) position
        // >> 2  = convert to u32 offset instead of byte offset (cmd_buffer = u32*)
        char* optval = reinterpret_cast<char*>(Memory::GetPointer(cmd_buffer[0x104 >> 2]));

        err = ::getsockopt(socket_handle, level, optname, optval, &optlen);
        if (err == SOCKET_ERROR_VALUE) {
            err = TranslateError(GET_ERRNO);
        }
    }

    cmd_buffer[0] = IPC::MakeHeader(0x11, 4, 2);
    cmd_buffer[1] = ret;
    cmd_buffer[2] = err;
    cmd_buffer[3] = optlen;
}

static void SetSockOpt(Interface* self) {
    u32* cmd_buffer = Kernel::GetCommandBuffer();
    u32 socket_handle = cmd_buffer[1];
    u32 level = cmd_buffer[2];
    int optname = TranslateSockOpt(cmd_buffer[3]);

    int ret = 0;
    int err = 0;

    if (optname < 0) {
#ifdef _WIN32
        err = WSAEINVAL;
#else
        err = EINVAL;
#endif
    } else {
        socklen_t optlen = static_cast<socklen_t>(cmd_buffer[4]);
        const char* optval = reinterpret_cast<const char*>(Memory::GetPointer(cmd_buffer[8]));

        err = static_cast<u32>(::setsockopt(socket_handle, level, optname, optval, optlen));
        if (err == SOCKET_ERROR_VALUE) {
            err = TranslateError(GET_ERRNO);
        }
    }

    cmd_buffer[0] = IPC::MakeHeader(0x12, 4, 4);
    cmd_buffer[1] = ret;
    cmd_buffer[2] = err;
}

const Interface::FunctionInfo FunctionTable[] = {
    {0x00010044, InitializeSockets, "InitializeSockets"},
    {0x000200C2, Socket, "Socket"},
    {0x00030082, Listen, "Listen"},
    {0x00040082, Accept, "Accept"},
    {0x00050084, Bind, "Bind"},
    {0x00060084, Connect, "Connect"},
    {0x00070104, nullptr, "recvfrom_other"},
    {0x00080102, RecvFrom, "RecvFrom"},
    {0x00090106, nullptr, "sendto_other"},
    {0x000A0106, SendTo, "SendTo"},
    {0x000B0042, Close, "Close"},
    {0x000C0082, Shutdown, "Shutdown"},
    {0x000D0082, nullptr, "GetHostByName"},
    {0x000E00C2, nullptr, "GetHostByAddr"},
    {0x000F0106, nullptr, "GetAddrInfo"},
    {0x00100102, nullptr, "GetNameInfo"},
    {0x00110102, GetSockOpt, "GetSockOpt"},
    {0x00120104, SetSockOpt, "SetSockOpt"},
    {0x001300C2, Fcntl, "Fcntl"},
    {0x00140084, Poll, "Poll"},
    {0x00150042, nullptr, "SockAtMark"},
    {0x00160000, GetHostId, "GetHostId"},
    {0x00170082, GetSockName, "GetSockName"},
    {0x00180082, GetPeerName, "GetPeerName"},
    {0x00190000, ShutdownSockets, "ShutdownSockets"},
    {0x001A00C0, nullptr, "GetNetworkOpt"},
    {0x001B0040, nullptr, "ICMPSocket"},
    {0x001C0104, nullptr, "ICMPPing"},
    {0x001D0040, nullptr, "ICMPCancel"},
    {0x001E0040, nullptr, "ICMPClose"},
    {0x001F0040, nullptr, "GetResolverInfo"},
    {0x00210002, nullptr, "CloseSockets"},
    {0x00230040, nullptr, "AddGlobalSocket"},
};

SOC_U::SOC_U() {
    Register(FunctionTable);
}

SOC_U::~SOC_U() {
    CleanupSockets();
}

} // namespace SOC
} // namespace Service