//! C definitions used by libnative that don't belong in liblibc

#![allow(nonstandard_style)]
#![cfg_attr(test, allow(dead_code))]
#![unstable(issue = "none", feature = "windows_c")]

use crate::ffi::CStr;
use crate::mem;
pub use crate::os::raw::c_int;
use crate::os::raw::{c_char, c_long, c_longlong, c_uint, c_ulong, c_ushort, c_void};
use crate::os::windows::io::{AsRawHandle, BorrowedHandle};
use crate::ptr;
use core::ffi::NonZero_c_ulong;

#[path = "c/windows_sys.rs"] // c.rs is included from two places so we need to specify this
mod windows_sys;
pub use windows_sys::*;

pub type DWORD = c_ulong;
pub type NonZeroDWORD = NonZero_c_ulong;
pub type LARGE_INTEGER = c_longlong;
pub type LONG = c_long;
pub type UINT = c_uint;
pub type WCHAR = u16;
pub type USHORT = c_ushort;
pub type SIZE_T = usize;
pub type WORD = u16;
pub type CHAR = c_char;
pub type ULONG = c_ulong;
pub type ACCESS_MASK = DWORD;

pub type LPCVOID = *const c_void;
pub type LPHANDLE = *mut HANDLE;
pub type LPOVERLAPPED = *mut OVERLAPPED;
pub type LPSECURITY_ATTRIBUTES = *mut SECURITY_ATTRIBUTES;
pub type LPVOID = *mut c_void;
pub type LPWCH = *mut WCHAR;
pub type LPWSTR = *mut WCHAR;

pub type PLARGE_INTEGER = *mut c_longlong;
pub type PSRWLOCK = *mut SRWLOCK;

pub type socklen_t = c_int;
pub type ADDRESS_FAMILY = USHORT;
pub use FD_SET as fd_set;
pub use LINGER as linger;
pub use TIMEVAL as timeval;

pub type CONDITION_VARIABLE = RTL_CONDITION_VARIABLE;
pub type SRWLOCK = RTL_SRWLOCK;
pub type INIT_ONCE = RTL_RUN_ONCE;

pub const CONDITION_VARIABLE_INIT: CONDITION_VARIABLE = CONDITION_VARIABLE { Ptr: ptr::null_mut() };
pub const SRWLOCK_INIT: SRWLOCK = SRWLOCK { Ptr: ptr::null_mut() };
pub const INIT_ONCE_STATIC_INIT: INIT_ONCE = INIT_ONCE { Ptr: ptr::null_mut() };

// Some windows_sys types have different signs than the types we use.
pub const OBJ_DONT_REPARSE: u32 = windows_sys::OBJ_DONT_REPARSE as u32;
pub const FRS_ERR_SYSVOL_POPULATE_TIMEOUT: u32 =
    windows_sys::FRS_ERR_SYSVOL_POPULATE_TIMEOUT as u32;
pub const AF_INET: c_int = windows_sys::AF_INET as c_int;
pub const AF_INET6: c_int = windows_sys::AF_INET6 as c_int;

#[repr(C)]
pub struct ip_mreq {
    pub imr_multiaddr: in_addr,
    pub imr_interface: in_addr,
}

#[repr(C)]
pub struct ipv6_mreq {
    pub ipv6mr_multiaddr: in6_addr,
    pub ipv6mr_interface: c_uint,
}

// Equivalent to the `NT_SUCCESS` C preprocessor macro.
// See: https://docs.microsoft.com/en-us/windows-hardware/drivers/kernel/using-ntstatus-values
pub fn nt_success(status: NTSTATUS) -> bool {
    status >= 0
}

impl UNICODE_STRING {
    pub fn from_ref(slice: &[u16]) -> Self {
        let len = slice.len() * mem::size_of::<u16>();
        Self { Length: len as _, MaximumLength: len as _, Buffer: slice.as_ptr() as _ }
    }
}

impl Default for OBJECT_ATTRIBUTES {
    fn default() -> Self {
        Self {
            Length: mem::size_of::<Self>() as _,
            RootDirectory: ptr::null_mut(),
            ObjectName: ptr::null_mut(),
            Attributes: 0,
            SecurityDescriptor: ptr::null_mut(),
            SecurityQualityOfService: ptr::null_mut(),
        }
    }
}

impl IO_STATUS_BLOCK {
    pub const PENDING: Self =
        IO_STATUS_BLOCK { Anonymous: IO_STATUS_BLOCK_0 { Status: STATUS_PENDING }, Information: 0 };
    pub fn status(&self) -> NTSTATUS {
        // SAFETY: If `self.Anonymous.Status` was set then this is obviously safe.
        // If `self.Anonymous.Pointer` was set then this is the equivalent to converting
        // the pointer to an integer, which is also safe.
        // Currently the only safe way to construct `IO_STATUS_BLOCK` outside of
        // this module is to call the `default` method, which sets the `Status`.
        unsafe { self.Anonymous.Status }
    }
}

/// NB: Use carefully! In general using this as a reference is likely to get the
/// provenance wrong for the `rest` field!
#[repr(C)]
pub struct REPARSE_DATA_BUFFER {
    pub ReparseTag: c_uint,
    pub ReparseDataLength: c_ushort,
    pub Reserved: c_ushort,
    pub rest: (),
}

/// NB: Use carefully! In general using this as a reference is likely to get the
/// provenance wrong for the `PathBuffer` field!
#[repr(C)]
pub struct SYMBOLIC_LINK_REPARSE_BUFFER {
    pub SubstituteNameOffset: c_ushort,
    pub SubstituteNameLength: c_ushort,
    pub PrintNameOffset: c_ushort,
    pub PrintNameLength: c_ushort,
    pub Flags: c_ulong,
    pub PathBuffer: WCHAR,
}

#[repr(C)]
pub struct MOUNT_POINT_REPARSE_BUFFER {
    pub SubstituteNameOffset: c_ushort,
    pub SubstituteNameLength: c_ushort,
    pub PrintNameOffset: c_ushort,
    pub PrintNameLength: c_ushort,
    pub PathBuffer: WCHAR,
}
#[repr(C)]
pub struct REPARSE_MOUNTPOINT_DATA_BUFFER {
    pub ReparseTag: DWORD,
    pub ReparseDataLength: DWORD,
    pub Reserved: WORD,
    pub ReparseTargetLength: WORD,
    pub ReparseTargetMaximumLength: WORD,
    pub Reserved1: WORD,
    pub ReparseTarget: WCHAR,
}

#[repr(C)]
pub struct SOCKADDR_STORAGE_LH {
    pub ss_family: ADDRESS_FAMILY,
    pub __ss_pad1: [CHAR; 6],
    pub __ss_align: i64,
    pub __ss_pad2: [CHAR; 112],
}

#[repr(C)]
#[derive(Copy, Clone)]
pub struct sockaddr_in {
    pub sin_family: ADDRESS_FAMILY,
    pub sin_port: USHORT,
    pub sin_addr: in_addr,
    pub sin_zero: [CHAR; 8],
}

#[repr(C)]
#[derive(Copy, Clone)]
pub struct sockaddr_in6 {
    pub sin6_family: ADDRESS_FAMILY,
    pub sin6_port: USHORT,
    pub sin6_flowinfo: c_ulong,
    pub sin6_addr: in6_addr,
    pub sin6_scope_id: c_ulong,
}

#[repr(C)]
#[derive(Copy, Clone)]
pub struct in_addr {
    pub s_addr: u32,
}

#[repr(C)]
#[derive(Copy, Clone)]
pub struct in6_addr {
    pub s6_addr: [u8; 16],
}

// Desktop specific functions & types
cfg_if::cfg_if! {
if #[cfg(not(target_vendor = "uwp"))] {
    pub const EXCEPTION_CONTINUE_SEARCH: i32 = 0;
}
}

pub unsafe extern "system" fn WriteFileEx(
    hFile: BorrowedHandle<'_>,
    lpBuffer: *mut ::core::ffi::c_void,
    nNumberOfBytesToWrite: u32,
    lpOverlapped: *mut OVERLAPPED,
    lpCompletionRoutine: LPOVERLAPPED_COMPLETION_ROUTINE,
) -> BOOL {
    windows_sys::WriteFileEx(
        hFile.as_raw_handle(),
        lpBuffer.cast::<u8>(),
        nNumberOfBytesToWrite,
        lpOverlapped,
        lpCompletionRoutine,
    )
}

pub unsafe extern "system" fn ReadFileEx(
    hFile: BorrowedHandle<'_>,
    lpBuffer: *mut ::core::ffi::c_void,
    nNumberOfBytesToRead: u32,
    lpOverlapped: *mut OVERLAPPED,
    lpCompletionRoutine: LPOVERLAPPED_COMPLETION_ROUTINE,
) -> BOOL {
    windows_sys::ReadFileEx(
        hFile.as_raw_handle(),
        lpBuffer,
        nNumberOfBytesToRead,
        lpOverlapped,
        lpCompletionRoutine,
    )
}

// POSIX compatibility shims.
pub unsafe fn recv(socket: SOCKET, buf: *mut c_void, len: c_int, flags: c_int) -> c_int {
    windows_sys::recv(socket, buf.cast::<u8>(), len, flags)
}
pub unsafe fn send(socket: SOCKET, buf: *const c_void, len: c_int, flags: c_int) -> c_int {
    windows_sys::send(socket, buf.cast::<u8>(), len, flags)
}
pub unsafe fn recvfrom(
    socket: SOCKET,
    buf: *mut c_void,
    len: c_int,
    flags: c_int,
    addr: *mut SOCKADDR,
    addrlen: *mut c_int,
) -> c_int {
    windows_sys::recvfrom(socket, buf.cast::<u8>(), len, flags, addr, addrlen)
}
pub unsafe fn sendto(
    socket: SOCKET,
    buf: *const c_void,
    len: c_int,
    flags: c_int,
    addr: *const SOCKADDR,
    addrlen: c_int,
) -> c_int {
    windows_sys::sendto(socket, buf.cast::<u8>(), len, flags, addr, addrlen)
}
pub unsafe fn getaddrinfo(
    node: *const c_char,
    service: *const c_char,
    hints: *const ADDRINFOA,
    res: *mut *mut ADDRINFOA,
) -> c_int {
    windows_sys::getaddrinfo(node.cast::<u8>(), service.cast::<u8>(), hints, res)
}

pub unsafe fn NtReadFile(
    filehandle: BorrowedHandle<'_>,
    event: HANDLE,
    apcroutine: PIO_APC_ROUTINE,
    apccontext: *mut c_void,
    iostatusblock: &mut IO_STATUS_BLOCK,
    buffer: *mut crate::mem::MaybeUninit<u8>,
    length: ULONG,
    byteoffset: Option<&LARGE_INTEGER>,
    key: Option<&ULONG>,
) -> NTSTATUS {
    windows_sys::NtReadFile(
        filehandle.as_raw_handle(),
        event,
        apcroutine,
        apccontext,
        iostatusblock,
        buffer.cast::<c_void>(),
        length,
        byteoffset.map(|o| o as *const i64).unwrap_or(ptr::null()),
        key.map(|k| k as *const u32).unwrap_or(ptr::null()),
    )
}
pub unsafe fn NtWriteFile(
    filehandle: BorrowedHandle<'_>,
    event: HANDLE,
    apcroutine: PIO_APC_ROUTINE,
    apccontext: *mut c_void,
    iostatusblock: &mut IO_STATUS_BLOCK,
    buffer: *const u8,
    length: ULONG,
    byteoffset: Option<&LARGE_INTEGER>,
    key: Option<&ULONG>,
) -> NTSTATUS {
    windows_sys::NtWriteFile(
        filehandle.as_raw_handle(),
        event,
        apcroutine,
        apccontext,
        iostatusblock,
        buffer.cast::<c_void>(),
        length,
        byteoffset.map(|o| o as *const i64).unwrap_or(ptr::null()),
        key.map(|k| k as *const u32).unwrap_or(ptr::null()),
    )
}

// Functions that aren't available on every version of Windows that we support,
// but we still use them and just provide some form of a fallback implementation.
compat_fn_with_fallback! {
    pub static KERNEL32: &CStr = ansi_str!("kernel32");

    // >= Win10 1607
    // https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-setthreaddescription
    pub fn SetThreadDescription(hthread: HANDLE, lpthreaddescription: PCWSTR) -> HRESULT {
        SetLastError(ERROR_CALL_NOT_IMPLEMENTED as DWORD); E_NOTIMPL
    }

    // >= Win8 / Server 2012
    // https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/nf-sysinfoapi-getsystemtimepreciseasfiletime
    pub fn GetSystemTimePreciseAsFileTime(lpsystemtimeasfiletime: *mut FILETIME) -> () {
        GetSystemTimeAsFileTime(lpsystemtimeasfiletime)
    }

    // >= Win11 / Server 2022
    // https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-gettemppath2a
    pub fn GetTempPath2W(bufferlength: u32, buffer: PWSTR) -> u32 {
        GetTempPathW(bufferlength, buffer)
    }
}

compat_fn_optional! {
    crate::sys::compat::load_synch_functions();
    pub fn WaitOnAddress(
        address: *const ::core::ffi::c_void,
        compareaddress: *const ::core::ffi::c_void,
        addresssize: usize,
        dwmilliseconds: u32
    ) -> BOOL;
    pub fn WakeByAddressSingle(address: *const ::core::ffi::c_void);
}

compat_fn_with_fallback! {
    pub static NTDLL: &CStr = ansi_str!("ntdll");

    pub fn NtCreateKeyedEvent(
        KeyedEventHandle: LPHANDLE,
        DesiredAccess: ACCESS_MASK,
        ObjectAttributes: LPVOID,
        Flags: ULONG
    ) -> NTSTATUS {
        panic!("keyed events not available")
    }
    pub fn NtReleaseKeyedEvent(
        EventHandle: HANDLE,
        Key: LPVOID,
        Alertable: BOOLEAN,
        Timeout: PLARGE_INTEGER
    ) -> NTSTATUS {
        panic!("keyed events not available")
    }
    pub fn NtWaitForKeyedEvent(
        EventHandle: HANDLE,
        Key: LPVOID,
        Alertable: BOOLEAN,
        Timeout: PLARGE_INTEGER
    ) -> NTSTATUS {
        panic!("keyed events not available")
    }
}