/// Variable argument version of `syscall`
#[macro_export]
macro_rules! syscall {
    ($nr:ident) => {
        $crate::syscall1($crate::nr::$nr, 0)
    };
    ($nr:ident, $a1:expr) => {
        $crate::syscall($crate::nr::$nr, &[$a1 as usize])
    };
    ($nr:ident, $a1:expr, $a2:expr) => {
        $crate::syscall($crate::nr::$nr, &[$a1 as usize, $a2 as usize])
    };
    ($nr:ident, $a1:expr, $a2:expr, $a3:expr) => {
        $crate::syscall($crate::nr::$nr, &[$a1 as usize, $a2 as usize, $a3 as usize])
    };
    ($nr:ident, $a1:expr, $a2:expr, $a3:expr, $a4:expr) => {
        $crate::syscall(
            $crate::nr::$nr,
            &[$a1 as usize, $a2 as usize, $a3 as usize, $a4 as usize],
        )
    };
}

/// Macro version of `syscall1`.
#[macro_export]
macro_rules! syscall1 {
    ($nr:ident, $a1:expr) => {
        $crate::syscall1($crate::nr::$nr, $a1 as usize)
    };
}

/// Macro for printing to the HOST standard output.
///
/// This is similar to the `print!` macro in the standard library. Both will panic on any failure to
/// print.
#[macro_export]
macro_rules! hprint {
    ($s:expr) => {
        $crate::export::hstdout_str($s)
    };
    ($($tt:tt)*) => {
        $crate::export::hstdout_fmt(format_args!($($tt)*))
    };
}

/// Macro for printing to the HOST standard output, with a newline.
///
/// This is similar to the `println!` macro in the standard library. Both will panic on any failure to
/// print.
#[macro_export]
macro_rules! hprintln {
    () => {
        $crate::export::hstdout_str("\n")
    };
    ($s:expr) => {
        $crate::export::hstdout_str(concat!($s, "\n"))
    };
    ($s:expr, $($tt:tt)*) => {
        $crate::export::hstdout_fmt(format_args!(concat!($s, "\n"), $($tt)*))
    };
}

/// Macro for printing to the HOST standard error.
///
/// This is similar to the `eprint!` macro in the standard library. Both will panic on any failure
/// to print.
#[macro_export]
macro_rules! heprint {
    ($s:expr) => {
        $crate::export::hstderr_str($s)
    };
    ($($tt:tt)*) => {
        $crate::export::hstderr_fmt(format_args!($($tt)*))
    };
}

/// Macro for printing to the HOST standard error, with a newline.
///
/// This is similar to the `eprintln!` macro in the standard library. Both will panic on any failure
/// to print.
#[macro_export]
macro_rules! heprintln {
    () => {
        $crate::export::hstderr_str("\n")
    };
    ($s:expr) => {
        $crate::export::hstderr_str(concat!($s, "\n"))
    };
    ($s:expr, $($tt:tt)*) => {
        $crate::export::hstderr_fmt(format_args!(concat!($s, "\n"), $($tt)*))
    };
}

/// Macro that prints and returns the value of a given expression for quick and
/// dirty debugging.
///
/// Works exactly like `dbg!` in the standard library, replacing `eprintln!`
/// with `heprintln!`.
#[macro_export]
macro_rules! dbg {
    () => {
        $crate::heprintln!("[{}:{}]", file!(), line!());
    };
    ($val:expr) => {
        // Use of `match` here is intentional because it affects the lifetimes
        // of temporaries - https://stackoverflow.com/a/48732525/1063961
        match $val {
            tmp => {
                $crate::heprintln!("[{}:{}] {} = {:#?}",
                    file!(), line!(), stringify!($val), &tmp);
                tmp
            }
        }
    };
    // Trailing comma with single argument is ignored
    ($val:expr,) => { $crate::dbg!($val) };
    ($($val:expr),+ $(,)?) => {
        ($($crate::dbg!($val)),+,)
    };
}