use {ArrayLength, GenericArray};
use core::fmt;
use core::ops::Add;
use core::str;
use typenum::*;
static LOWER_CHARS: &'static [u8] = b"0123456789abcdef";
static UPPER_CHARS: &'static [u8] = b"0123456789ABCDEF";
impl<T: ArrayLength<u8>> fmt::LowerHex for GenericArray<u8, T>
where
T: Add<T>,
<T as Add<T>>::Output: ArrayLength<u8>,
{
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let max_digits = f.precision().unwrap_or_else(|| self.len());
if T::to_usize() < 1024 {
let mut res = GenericArray::<u8, Sum<T, T>>::default();
for (i, c) in self.iter().take(max_digits).enumerate() {
res[i * 2] = LOWER_CHARS[(c >> 4) as usize];
res[i * 2 + 1] = LOWER_CHARS[(c & 0xF) as usize];
}
f.write_str(unsafe { str::from_utf8_unchecked(&res[..max_digits * 2]) })?;
} else {
let mut buf = [0u8; 2048];
for chunk in self[..max_digits].chunks(1024) {
for (i, c) in chunk.iter().enumerate() {
buf[i * 2] = LOWER_CHARS[(c >> 4) as usize];
buf[i * 2 + 1] = LOWER_CHARS[(c & 0xF) as usize];
}
f.write_str(unsafe { str::from_utf8_unchecked(&buf[..chunk.len() * 2]) })?;
}
}
Ok(())
}
}
impl<T: ArrayLength<u8>> fmt::UpperHex for GenericArray<u8, T>
where
T: Add<T>,
<T as Add<T>>::Output: ArrayLength<u8>,
{
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let max_digits = f.precision().unwrap_or_else(|| self.len());
if T::to_usize() < 1024 {
let mut res = GenericArray::<u8, Sum<T, T>>::default();
for (i, c) in self.iter().take(max_digits).enumerate() {
res[i * 2] = UPPER_CHARS[(c >> 4) as usize];
res[i * 2 + 1] = UPPER_CHARS[(c & 0xF) as usize];
}
f.write_str(unsafe { str::from_utf8_unchecked(&res[..max_digits * 2]) })?;
} else {
let mut buf = [0u8; 2048];
for chunk in self[..max_digits].chunks(1024) {
for (i, c) in chunk.iter().enumerate() {
buf[i * 2] = UPPER_CHARS[(c >> 4) as usize];
buf[i * 2 + 1] = UPPER_CHARS[(c & 0xF) as usize];
}
f.write_str(unsafe { str::from_utf8_unchecked(&buf[..chunk.len() * 2]) })?;
}
}
Ok(())
}
}