use core::ffi::{c_char, c_int};

use yggdrasil_rt::io::{FileAttr, FileMode, FileType};

use crate::{
    error::CIntZeroResult,
    util::{self, PointerStrExt},
};

use super::{
    fcntl::{AT_FDCWD, AT_SYMLINK_NOFOLLOW},
    sys_time::__ygg_timespec_t,
    sys_types::{blkcnt_t, blksize_t, dev_t, gid_t, ino_t, mode_t, nlink_t, off_t, uid_t},
};

#[derive(Clone, Copy, PartialEq, Eq, Debug, Default)]
#[repr(C)]
pub struct stat {
    pub st_dev: dev_t,
    pub st_ino: ino_t,
    pub st_mode: mode_t,
    pub st_nlink: nlink_t,
    pub st_uid: uid_t,
    pub st_gid: gid_t,
    pub st_rdev: dev_t,
    pub st_size: off_t,
    pub st_atim: __ygg_timespec_t,
    pub st_mtim: __ygg_timespec_t,
    pub st_ctim: __ygg_timespec_t,
    pub st_blksize: blksize_t,
    pub st_blocks: blkcnt_t,
}

pub const S_IFMT: c_int = 0xF << 16;
pub const S_IFBLK: c_int = 1 << 16;
pub const S_IFCHR: c_int = 2 << 16;
pub const S_IFIFO: c_int = 3 << 16;
pub const S_IFREG: c_int = 4 << 16;
pub const S_IFDIR: c_int = 5 << 16;
pub const S_IFLNK: c_int = 6 << 16;
pub const S_IFSOCK: c_int = 7 << 16;

pub const S_IRWXU: c_int = 0x7 << 6;
pub const S_IRUSR: c_int = 0x4 << 6;
pub const S_IWUSR: c_int = 0x2 << 6;
pub const S_IXUSR: c_int = 0x1 << 6;

pub const S_IRWXG: c_int = 0x7 << 3;
pub const S_IRGRP: c_int = 0x4 << 3;
pub const S_IWGRP: c_int = 0x2 << 3;
pub const S_IXGRP: c_int = 0x1 << 3;

pub const S_IRWXO: c_int = 0x7 << 0;
pub const S_IROTH: c_int = 0x4 << 0;
pub const S_IWOTH: c_int = 0x2 << 0;
pub const S_IXOTH: c_int = 0x1 << 0;

pub const S_ISUID: c_int = 1 << 11;
pub const S_ISGID: c_int = 1 << 10;
pub const S_ISVTX: c_int = 1 << 9;

impl From<FileAttr> for stat {
    fn from(value: FileAttr) -> Self {
        // TODO no translation for st_dev/st_rdev/st_ino/etc
        let mut st = Self::default();
        st.st_mode = (value.mode.bits() & 0o777) as _;
        match value.ty {
            FileType::Block => st.st_mode |= S_IFBLK,
            FileType::Char => st.st_mode |= S_IFCHR,
            FileType::File => st.st_mode |= S_IFREG,
            FileType::Directory => st.st_mode |= S_IFDIR,
            FileType::Symlink => st.st_mode |= S_IFLNK,
        }
        st.st_size = value.size.try_into().unwrap();
        // TODO
        st.st_uid = u32::from(value.uid).try_into().unwrap();
        st.st_gid = u32::from(value.gid).try_into().unwrap();
        // TODO
        st.st_blksize = 512;
        st.st_blocks = (st.st_size + 511) / 512;
        // TODO
        st.st_nlink = 1;

        st
    }
}

#[no_mangle]
unsafe extern "C" fn chmod(_pathname: *const c_char, _mode: mode_t) -> c_int {
    todo!()
}

#[no_mangle]
unsafe extern "C" fn fchmod(_fd: c_int, _mode: mode_t) -> c_int {
    todo!()
}

#[no_mangle]
unsafe extern "C" fn fchmodat(
    _fd: c_int,
    _pathname: *const c_char,
    _mode: mode_t,
    _opt: c_int,
) -> c_int {
    todo!()
}

#[no_mangle]
unsafe extern "C" fn umask(_mode: mode_t) -> mode_t {
    todo!()
    // let new = FileMode::new((mode as u32) & 0o777);
    // let old = process::update_umask(new);
    // old.bits() as mode_t
}

// Create stuff

#[no_mangle]
unsafe extern "C" fn mkdir(pathname: *const c_char, mode: mode_t) -> CIntZeroResult {
    mkdirat(AT_FDCWD, pathname, mode)
}

#[no_mangle]
unsafe extern "C" fn mkdirat(atfd: c_int, pathname: *const c_char, mode: mode_t) -> CIntZeroResult {
    let _pathname = pathname.ensure_str();
    let _atfd = util::at_fd(atfd)?;
    let _mode = FileMode::new((mode & 0o777) as u32);

    todo!()
    // io::create_directory(atfd, pathname, mode)?;

    // CIntZeroResult::OK
}

#[no_mangle]
unsafe extern "C" fn mkfifo(_pathname: *const c_char, _mode: mode_t) -> c_int {
    unimplemented!()
}

#[no_mangle]
unsafe extern "C" fn mkfifoat(_atfd: c_int, _pathname: *const c_char, _mode: mode_t) -> c_int {
    unimplemented!()
}

#[no_mangle]
unsafe extern "C" fn mknod(_pathname: *const c_char, _mode: mode_t, _dev: dev_t) -> c_int {
    unimplemented!()
}

#[no_mangle]
unsafe extern "C" fn mknodat(
    _atfd: c_int,
    _pathname: *const c_char,
    _mode: mode_t,
    _dev: dev_t,
) -> c_int {
    unimplemented!()
}

// File status

#[no_mangle]
unsafe extern "C" fn fstat(_fd: c_int, _statbuf: *mut stat) -> CIntZeroResult {
    todo!()
    // let fd = RawFd::e_try_from(fd)?;
    // let attr = io::get_metadata(Some(fd), "", false)?;

    // if let Some(statbuf) = statbuf.as_mut() {
    //     *statbuf = attr.into();
    // }

    // CIntZeroResult::OK
}

#[no_mangle]
unsafe extern "C" fn fstatat(
    atfd: c_int,
    pathname: *const c_char,
    _statbuf: *mut stat,
    opt: c_int,
) -> CIntZeroResult {
    let _pathname = pathname.ensure_str();
    let _atfd = util::at_fd(atfd)?;
    let _follow = opt & AT_SYMLINK_NOFOLLOW == 0;

    todo!()
    // let attr = io::get_metadata(atfd, pathname, follow)?;

    // if let Some(statbuf) = statbuf.as_mut() {
    //     *statbuf = attr.into();
    // }

    // CIntZeroResult::OK
}

#[no_mangle]
unsafe extern "C" fn lstat(pathname: *const c_char, statbuf: *mut stat) -> CIntZeroResult {
    fstatat(AT_FDCWD, pathname, statbuf, AT_SYMLINK_NOFOLLOW)
}

#[no_mangle]
unsafe extern "C" fn stat(pathname: *const c_char, statbuf: *mut stat) -> CIntZeroResult {
    fstatat(AT_FDCWD, pathname, statbuf, 0)
}

// File time updates

#[no_mangle]
unsafe extern "C" fn futimens(_fd: c_int, _times: *const __ygg_timespec_t) -> c_int {
    todo!()
}

#[no_mangle]
unsafe extern "C" fn utimensat(
    _atfd: c_int,
    _pathname: *const c_char,
    _times: *const __ygg_timespec_t,
    _opt: c_int,
) -> c_int {
    todo!()
}