#[cfg(any(apple_targets, target_os = "openbsd"))]

pub use libc::c_uint;

#[cfg(any(target_os = "netbsd", freebsdlike))]

pub use libc::c_ulong;

pub use libc::stat as FileStat;

pub use libc::{dev_t, mode_t};

#[cfg(not(target_os = "redox"))]

use crate::fcntl::{at_rawfd, AtFlags};

use crate::sys::time::{TimeSpec, TimeVal};

use crate::{errno::Errno, NixPath, Result};

use std::mem;

use std::os::unix::io::RawFd;

libc_bitflags!(

    /// "File type" flags for `mknod` and related functions.

    pub struct SFlag: mode_t {

        S_IFIFO;

        S_IFCHR;

        S_IFDIR;

        S_IFBLK;

        S_IFREG;

        S_IFLNK;

        S_IFSOCK;

        S_IFMT;

    }

);

libc_bitflags! {

    /// "File mode / permissions" flags.

    pub struct Mode: mode_t {

        /// Read, write and execute for owner.

        S_IRWXU;

        /// Read for owner.

        S_IRUSR;

        /// Write for owner.

        S_IWUSR;

        /// Execute for owner.

        S_IXUSR;

        /// Read write and execute for group.

        S_IRWXG;

        /// Read for group.

        S_IRGRP;

        /// Write for group.

        S_IWGRP;

        /// Execute for group.

        S_IXGRP;

        /// Read, write and execute for other.

        S_IRWXO;

        /// Read for other.

        S_IROTH;

        /// Write for other.

        S_IWOTH;

        /// Execute for other.

        S_IXOTH;

        /// Set user id on execution.

        S_ISUID as mode_t;

        /// Set group id on execution.

        S_ISGID as mode_t;

        S_ISVTX as mode_t;

    }

}

#[cfg(any(apple_targets, target_os = "openbsd"))]

pub type type_of_file_flag = c_uint;

#[cfg(any(freebsdlike, target_os = "netbsd"))]

pub type type_of_file_flag = c_ulong;

#[cfg(bsd)]

libc_bitflags! {

    /// File flags.

    pub struct FileFlag: type_of_file_flag {

        /// The file may only be appended to.

        SF_APPEND;

        /// The file has been archived.

        SF_ARCHIVED;

        #[cfg(any(target_os = "dragonfly"))]

        SF_CACHE;

        /// The file may not be changed.

        SF_IMMUTABLE;

        /// Indicates a WAPBL journal file.

        #[cfg(any(target_os = "netbsd"))]

        SF_LOG;

        /// Do not retain history for file

        #[cfg(any(target_os = "dragonfly"))]

        SF_NOHISTORY;

        /// The file may not be renamed or deleted.

        #[cfg(freebsdlike)]

        SF_NOUNLINK;

        /// Mask of superuser changeable flags

        SF_SETTABLE;

        /// Snapshot is invalid.

        #[cfg(any(target_os = "netbsd"))]

        SF_SNAPINVAL;

        /// The file is a snapshot file.

        #[cfg(any(target_os = "netbsd", target_os = "freebsd"))]

        SF_SNAPSHOT;

        #[cfg(any(target_os = "dragonfly"))]

        SF_XLINK;

        /// The file may only be appended to.

        UF_APPEND;

        /// The file needs to be archived.

        #[cfg(any(target_os = "freebsd"))]

        UF_ARCHIVE;

        #[cfg(any(target_os = "dragonfly"))]

        UF_CACHE;

        /// File is compressed at the file system level.

        #[cfg(apple_targets)]

        UF_COMPRESSED;

        /// The file may be hidden from directory listings at the application's

        /// discretion.

        #[cfg(any(

            target_os = "freebsd",

            apple_targets,

        ))]

        UF_HIDDEN;

        /// The file may not be changed.

        UF_IMMUTABLE;

        /// Do not dump the file.

        UF_NODUMP;

        #[cfg(any(target_os = "dragonfly"))]

        UF_NOHISTORY;

        /// The file may not be renamed or deleted.

        #[cfg(freebsdlike)]

        UF_NOUNLINK;

        /// The file is offline, or has the Windows and CIFS

        /// `FILE_ATTRIBUTE_OFFLINE` attribute.

        #[cfg(any(target_os = "freebsd"))]

        UF_OFFLINE;

        /// The directory is opaque when viewed through a union stack.

        UF_OPAQUE;

        /// The file is read only, and may not be written or appended.

        #[cfg(any(target_os = "freebsd"))]

        UF_READONLY;

        /// The file contains a Windows reparse point.

        #[cfg(any(target_os = "freebsd"))]

        UF_REPARSE;

        /// Mask of owner changeable flags.

        UF_SETTABLE;

        /// The file has the Windows `FILE_ATTRIBUTE_SPARSE_FILE` attribute.

        #[cfg(any(target_os = "freebsd"))]

        UF_SPARSE;

        /// The file has the DOS, Windows and CIFS `FILE_ATTRIBUTE_SYSTEM`

        /// attribute.

        #[cfg(any(target_os = "freebsd"))]

        UF_SYSTEM;

        /// File renames and deletes are tracked.

        #[cfg(apple_targets)]

        UF_TRACKED;

        #[cfg(any(target_os = "dragonfly"))]

        UF_XLINK;

    }

}

/// Create a special or ordinary file, by pathname.

pub fn mknod<P: ?Sized + NixPath>(

    path: &P,

    kind: SFlag,

    perm: Mode,

    dev: dev_t,

) -> Result<()> {

    let res = path.with_nix_path(|cstr| unsafe {

        libc::mknod(cstr.as_ptr(), kind.bits() | perm.bits() as mode_t, dev)

    })?;

    Errno::result(res).map(drop)

}

/// Create a special or ordinary file, relative to a given directory.

#[cfg(not(any(apple_targets, target_os = "redox", target_os = "haiku")))]

pub fn mknodat<P: ?Sized + NixPath>(

    dirfd: Option<RawFd>,

    path: &P,

    kind: SFlag,

    perm: Mode,

    dev: dev_t,

) -> Result<()> {

    let dirfd = at_rawfd(dirfd);

    let res = path.with_nix_path(|cstr| unsafe {

        libc::mknodat(

            dirfd,

            cstr.as_ptr(),

            kind.bits() | perm.bits() as mode_t,

            dev,

        )

    })?;

    Errno::result(res).map(drop)

}

#[cfg(target_os = "linux")]

pub const fn major(dev: dev_t) -> u64 {

    ((dev >> 32) & 0xffff_f000) | ((dev >> 8) & 0x0000_0fff)

}

#[cfg(target_os = "linux")]

pub const fn minor(dev: dev_t) -> u64 {

    ((dev >> 12) & 0xffff_ff00) | ((dev) & 0x0000_00ff)

}

#[cfg(target_os = "linux")]

pub const fn makedev(major: u64, minor: u64) -> dev_t {

    ((major & 0xffff_f000) << 32)

        | ((major & 0x0000_0fff) << 8)

        | ((minor & 0xffff_ff00) << 12)

        | (minor & 0x0000_00ff)

}

pub fn umask(mode: Mode) -> Mode {

    let prev = unsafe { libc::umask(mode.bits() as mode_t) };

    Mode::from_bits(prev).expect("[BUG] umask returned invalid Mode")

}

pub fn stat<P: ?Sized + NixPath>(path: &P) -> Result<FileStat> {

    let mut dst = mem::MaybeUninit::uninit();

    let res = path.with_nix_path(|cstr| unsafe {

        libc::stat(cstr.as_ptr(), dst.as_mut_ptr())

    })?;

    Errno::result(res)?;

    Ok(unsafe { dst.assume_init() })

}

pub fn lstat<P: ?Sized + NixPath>(path: &P) -> Result<FileStat> {

    let mut dst = mem::MaybeUninit::uninit();

    let res = path.with_nix_path(|cstr| unsafe {

        libc::lstat(cstr.as_ptr(), dst.as_mut_ptr())

    })?;

    Errno::result(res)?;

    Ok(unsafe { dst.assume_init() })

}

pub fn fstat(fd: RawFd) -> Result<FileStat> {

    let mut dst = mem::MaybeUninit::uninit();

    let res = unsafe { libc::fstat(fd, dst.as_mut_ptr()) };

    Errno::result(res)?;

    Ok(unsafe { dst.assume_init() })

}

#[cfg(not(target_os = "redox"))]

pub fn fstatat<P: ?Sized + NixPath>(

    dirfd: Option<RawFd>,

    pathname: &P,

    f: AtFlags,

) -> Result<FileStat> {

    let dirfd = at_rawfd(dirfd);

    let mut dst = mem::MaybeUninit::uninit();

    let res = pathname.with_nix_path(|cstr| unsafe {

        libc::fstatat(

            dirfd,

            cstr.as_ptr(),

            dst.as_mut_ptr(),

            f.bits() as libc::c_int,

        )

    })?;

    Errno::result(res)?;

    Ok(unsafe { dst.assume_init() })

}

/// Change the file permission bits of the file specified by a file descriptor.

///

/// # References

///

/// [fchmod(2)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/fchmod.html).

pub fn fchmod(fd: RawFd, mode: Mode) -> Result<()> {

    let res = unsafe { libc::fchmod(fd, mode.bits() as mode_t) };

    Errno::result(res).map(drop)

}

/// Flags for `fchmodat` function.

#[derive(Clone, Copy, Debug)]

pub enum FchmodatFlags {

    FollowSymlink,

    NoFollowSymlink,

}

/// Change the file permission bits.

///

/// The file to be changed is determined relative to the directory associated

/// with the file descriptor `dirfd` or the current working directory

/// if `dirfd` is `None`.

///

/// If `flag` is `FchmodatFlags::NoFollowSymlink` and `path` names a symbolic link,

/// then the mode of the symbolic link is changed.

///

/// `fchmodat(None, path, mode, FchmodatFlags::FollowSymlink)` is identical to

/// a call `libc::chmod(path, mode)`. That's why `chmod` is unimplemented

/// in the `nix` crate.

///

/// # References

///

/// [fchmodat(2)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/fchmodat.html).

#[cfg(not(target_os = "redox"))]

pub fn fchmodat<P: ?Sized + NixPath>(

    dirfd: Option<RawFd>,

    path: &P,

    mode: Mode,

    flag: FchmodatFlags,

) -> Result<()> {

    let atflag = match flag {

        FchmodatFlags::FollowSymlink => AtFlags::empty(),

        FchmodatFlags::NoFollowSymlink => AtFlags::AT_SYMLINK_NOFOLLOW,

    };

    let res = path.with_nix_path(|cstr| unsafe {

        libc::fchmodat(

            at_rawfd(dirfd),

            cstr.as_ptr(),

            mode.bits() as mode_t,

            atflag.bits() as libc::c_int,

        )

    })?;

    Errno::result(res).map(drop)

}

/// Change the access and modification times of a file.

///

/// `utimes(path, times)` is identical to

/// `utimensat(None, path, times, UtimensatFlags::FollowSymlink)`. The former

/// is a deprecated API so prefer using the latter if the platforms you care

/// about support it.

///

/// # References

///

/// [utimes(2)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/utimes.html).

pub fn utimes<P: ?Sized + NixPath>(

    path: &P,

    atime: &TimeVal,

    mtime: &TimeVal,

) -> Result<()> {

    let times: [libc::timeval; 2] = [*atime.as_ref(), *mtime.as_ref()];

    let res = path.with_nix_path(|cstr| unsafe {

        libc::utimes(cstr.as_ptr(), &times[0])

    })?;

    Errno::result(res).map(drop)

}

/// Change the access and modification times of a file without following symlinks.

///

/// `lutimes(path, times)` is identical to

/// `utimensat(None, path, times, UtimensatFlags::NoFollowSymlink)`. The former

/// is a deprecated API so prefer using the latter if the platforms you care

/// about support it.

///

/// # References

///

/// [lutimes(2)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/lutimes.html).

#[cfg(any(

    target_os = "linux",

    target_os = "haiku",

    apple_targets,

    target_os = "freebsd",

    target_os = "netbsd"

))]

pub fn lutimes<P: ?Sized + NixPath>(

    path: &P,

    atime: &TimeVal,

    mtime: &TimeVal,

) -> Result<()> {

    let times: [libc::timeval; 2] = [*atime.as_ref(), *mtime.as_ref()];

    let res = path.with_nix_path(|cstr| unsafe {

        libc::lutimes(cstr.as_ptr(), &times[0])

    })?;

    Errno::result(res).map(drop)

}

/// Change the access and modification times of the file specified by a file descriptor.

///

/// If you want to set the timestamp to now, use `TimeSpec::UTIME_NOW`. Use

/// `TimeSpec::UTIME_OMIT` if you don't want to change it.

///

/// # References

///

/// [futimens(2)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/futimens.html).

#[inline]

pub fn futimens(fd: RawFd, atime: &TimeSpec, mtime: &TimeSpec) -> Result<()> {

    let times: [libc::timespec; 2] = [*atime.as_ref(), *mtime.as_ref()];

    let res = unsafe { libc::futimens(fd, &times[0]) };

    Errno::result(res).map(drop)

}

/// Flags for `utimensat` function.

// TODO: replace with fcntl::AtFlags

#[derive(Clone, Copy, Debug)]

pub enum UtimensatFlags {

    FollowSymlink,

    NoFollowSymlink,

}

/// Change the access and modification times of a file.

///

/// The file to be changed is determined relative to the directory associated

/// with the file descriptor `dirfd` or the current working directory

/// if `dirfd` is `None`.

///

/// If `flag` is `UtimensatFlags::NoFollowSymlink` and `path` names a symbolic link,

/// then the mode of the symbolic link is changed.

///

/// `utimensat(None, path, times, UtimensatFlags::FollowSymlink)` is identical to

/// `utimes(path, times)`. The latter is a deprecated API so prefer using the

/// former if the platforms you care about support it.

///

/// If you want to set the timestamp to now, use `TimeSpec::UTIME_NOW`. Use

/// `TimeSpec::UTIME_OMIT` if you don't want to change it.

///

/// # References

///

/// [utimensat(2)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/utimens.html).

#[cfg(not(target_os = "redox"))]

pub fn utimensat<P: ?Sized + NixPath>(

    dirfd: Option<RawFd>,

    path: &P,

    atime: &TimeSpec,

    mtime: &TimeSpec,

    flag: UtimensatFlags,

) -> Result<()> {

    let atflag = match flag {

        UtimensatFlags::FollowSymlink => AtFlags::empty(),

        UtimensatFlags::NoFollowSymlink => AtFlags::AT_SYMLINK_NOFOLLOW,

    };

    let times: [libc::timespec; 2] = [*atime.as_ref(), *mtime.as_ref()];

    let res = path.with_nix_path(|cstr| unsafe {

        libc::utimensat(

            at_rawfd(dirfd),

            cstr.as_ptr(),

            &times[0],

            atflag.bits() as libc::c_int,

        )

    })?;

    Errno::result(res).map(drop)

}

#[cfg(not(target_os = "redox"))]

pub fn mkdirat<P: ?Sized + NixPath>(

    fd: Option<RawFd>,

    path: &P,

    mode: Mode,

) -> Result<()> {

    let fd = at_rawfd(fd);

    let res = path.with_nix_path(|cstr| unsafe {

        libc::mkdirat(fd, cstr.as_ptr(), mode.bits() as mode_t)

    })?;

    Errno::result(res).map(drop)

}