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use super::*;
use std::{
char::REPLACEMENT_CHARACTER,
io::{ErrorKind, Read, Stdout, Write},
path::Path,
};
#[non_exhaustive]
pub enum Output {
Buffer(Vec<u8>),
Writer(Box<dyn Write + Sync + Send + 'static>),
}
impl Output {
fn putc(&mut self, c: char) -> std::io::Result<()> {
let mut a = [0u8; 4];
let bytes = c.encode_utf8(&mut a).as_bytes();
match self {
Self::Buffer(b) => b.extend_from_slice(&bytes),
Self::Writer(w) => w.write_all(&bytes)?,
}
Ok(())
}
}
impl From<Vec<u8>> for Output {
fn from(v: Vec<u8>) -> Self {
Self::Buffer(v)
}
}
impl From<Box<dyn Write + Sync + Send + 'static>> for Output {
fn from(w: Box<dyn Write + Sync + Send + 'static>) -> Self {
Self::Writer(w)
}
}
impl From<Stdout> for Output {
fn from(o: Stdout) -> Self {
Self::Writer(Box::new(o))
}
}
pub struct Ctx {
pub(crate) stdin: Box<dyn std::io::Read + Send + 'static>,
pub(crate) stdout: Output,
last_char: Option<char>,
}
impl Ctx {
pub fn new<I, O>(stdin: I, stdout: O) -> Self
where
I: Read + 'static + Sync + Send,
O: Into<Output>,
{
Self {
stdin: Box::new(stdin),
stdout: stdout.into(),
last_char: None,
}
}
pub(crate) fn putc(&mut self, c: char) -> Result<(), Error> {
self.stdout.putc(c).map_err(Into::into)
}
pub(crate) fn getc(&mut self) -> Result<Option<char>, Error> {
let c = Self::read_single_char(&mut self.stdin)?;
self.last_char = c;
Ok(c)
}
pub(crate) fn last_char(&self) -> Option<char> {
self.last_char
}
pub fn execute(&mut self, expr: P<Expr>) -> Result<(), Error> {
let mut task = Task::Eval(expr, p(Cont::Final));
while let Some(t) = task.run(self)? {
task = t;
}
Ok(())
}
fn read_single_char(mut r: impl Read) -> Result<Option<char>, Error> {
let mut first = 0u8;
if let Err(e) = r.read_exact(std::slice::from_mut(&mut first)) {
return if e.kind() == ErrorKind::UnexpectedEof {
Ok(None)
} else {
Err(e.into())
};
}
let width = match utf8_char_width(first) {
1 => return Ok(Some(first as char)),
0 => return Ok(Some(REPLACEMENT_CHARACTER)),
n => n as usize,
};
let mut buf = [first, 0, 0, 0];
if let Err(e) = r.read_exact(&mut buf[1..width]) {
return if e.kind() == ErrorKind::UnexpectedEof {
return Ok(Some(REPLACEMENT_CHARACTER));
} else {
Err(e.into())
};
}
Ok(Some(
std::str::from_utf8(&buf[..width])
.ok()
.and_then(|s| s.chars().next())
.unwrap_or(REPLACEMENT_CHARACTER),
))
}
}
fn utf8_char_width(first_byte: u8) -> usize {
match first_byte {
0b0000_0000..=0b0111_1111 => 1,
0b1000_0000..=0b1011_1111 => 0,
0b1100_0000..=0b1101_1111 => 2,
0b1110_0000..=0b1110_1111 => 3,
0b1111_0000..=0b1111_0111 => 4,
0b1111_1000..=0b1111_1111 => 0,
}
}
#[derive(Copy, Clone, Debug, PartialEq)]
pub enum Input<'a> {
Str(&'a str),
File(&'a Path),
Stdin,
}
impl Input<'_> {
pub fn parse(&self) -> Result<P<Expr>, ParseError> {
let o = crate::ParseOptions {
log_warnings: true,
strict: false,
};
match self {
Self::Str(s) => parse_from_str(*s, o),
Self::File(s) => parse_from_file(*s, o),
Self::Stdin => parse_from_stdin(o),
}
}
}
impl<'a> From<&'a str> for Input<'a> {
fn from(s: &'a str) -> Self {
Self::Str(s)
}
}
impl<'a> From<&'a Path> for Input<'a> {
fn from(s: &'a Path) -> Self {
Self::File(s)
}
}
impl Default for Input<'_> {
#[inline]
fn default() -> Self {
Self::Str("")
}
}