use nom::branch::alt;
use nom::bytes::complete::*;
use nom::character::complete::*;
use nom::combinator::*;
use nom::error::ErrorKind;
use nom::number::complete::double;
use nom::Err;
use nom::IResult;
use crate::named::NAMED_COLORS;
use crate::Color;
fn hex_to_u8_unsafe(num: &str) -> u8 {
u8::from_str_radix(num, 16).unwrap()
}
fn rgb(r: u8, g: u8, b: u8) -> Color {
Color::from_rgb(r, g, b)
}
fn rgba(r: u8, g: u8, b: u8, a: f64) -> Color {
Color::from_rgba(r, g, b, a)
}
fn comma_separated(input: &str) -> IResult<&str, &str> {
let (input, _) = space0(input)?;
let (input, _) = char(',')(input)?;
space0(input)
}
fn parse_separator(input: &str) -> IResult<&str, &str> {
alt((comma_separated, space1))(input)
}
fn opt_hash_char(s: &str) -> IResult<&str, Option<char>> {
opt(char('#'))(s)
}
fn parse_percentage(input: &str) -> IResult<&str, f64> {
let (input, percent) = double(input)?;
let (input, _) = char('%')(input)?;
Ok((input, percent / 100.))
}
fn parse_degrees(input: &str) -> IResult<&str, f64> {
let (input, d) = double(input)?;
let (input, _) = alt((tag("°"), tag("deg"), tag("")))(input)?;
Ok((input, d))
}
fn parse_rads(input: &str) -> IResult<&str, f64> {
let (input, rads) = double(input)?;
let (input, _) = tag("rad")(input)?;
Ok((input, rads * 180. / std::f64::consts::PI))
}
fn parse_grads(input: &str) -> IResult<&str, f64> {
let (input, grads) = double(input)?;
let (input, _) = tag("grad")(input)?;
Ok((input, grads * 360. / 400.))
}
fn parse_turns(input: &str) -> IResult<&str, f64> {
let (input, turns) = double(input)?;
let (input, _) = tag("turn")(input)?;
Ok((input, turns * 360.))
}
fn parse_angle(input: &str) -> IResult<&str, f64> {
alt((parse_turns, parse_grads, parse_rads, parse_degrees))(input)
}
fn parse_alpha<'a>(input: &'a str) -> IResult<&'a str, f64> {
let (input, alpha) = opt(|input: &'a str| {
let (input, _) = parse_separator(input)?;
alt((parse_percentage, double))(input)
})(input)?;
Ok((input, alpha.unwrap_or(1.0)))
}
fn parse_hex(input: &str) -> IResult<&str, Color> {
let (input, _) = opt_hash_char(input)?;
let (input, hex_chars) = hex_digit1(input)?;
match hex_chars.len() {
6 => {
let r = hex_to_u8_unsafe(&hex_chars[0..2]);
let g = hex_to_u8_unsafe(&hex_chars[2..4]);
let b = hex_to_u8_unsafe(&hex_chars[4..6]);
Ok((input, rgb(r, g, b)))
}
3 => {
let r = hex_to_u8_unsafe(&hex_chars[0..1]);
let g = hex_to_u8_unsafe(&hex_chars[1..2]);
let b = hex_to_u8_unsafe(&hex_chars[2..3]);
let r = r * 16 + r;
let g = g * 16 + g;
let b = b * 16 + b;
Ok((input, rgb(r, g, b)))
}
8 => {
let r = hex_to_u8_unsafe(&hex_chars[0..2]);
let g = hex_to_u8_unsafe(&hex_chars[2..4]);
let b = hex_to_u8_unsafe(&hex_chars[4..6]);
let a = hex_to_u8_unsafe(&hex_chars[6..8]) as f64 / 255.0;
Ok((input, rgba(r, g, b, a)))
}
4 => {
let r = hex_to_u8_unsafe(&hex_chars[0..1]);
let g = hex_to_u8_unsafe(&hex_chars[1..2]);
let b = hex_to_u8_unsafe(&hex_chars[2..3]);
let a = hex_to_u8_unsafe(&hex_chars[3..4]);
let r = r * 16 + r;
let g = g * 16 + g;
let b = b * 16 + b;
let a = (a * 16 + a) as f64 / 255.0;
Ok((input, rgba(r, g, b, a)))
}
_ => Err(Err::Error(nom::error::Error::new(
"Expected hex string of 3 or 6 characters length",
ErrorKind::Many1,
))),
}
}
fn parse_numeric_rgb(input: &str) -> IResult<&str, Color> {
let (input, prefixed) = opt(alt((tag("rgb("), tag("rgba("))))(input)?;
let is_prefixed = prefixed.is_some();
let (input, _) = space0(input)?;
let (input, r) = double(input)?;
let (input, _) = parse_separator(input)?;
let (input, g) = double(input)?;
let (input, _) = parse_separator(input)?;
let (input, b) = double(input)?;
let (input, alpha) = parse_alpha(input)?;
let (input, _) = space0(input)?;
let (input, _) = cond(is_prefixed, char(')'))(input)?;
let r = r / 255.;
let g = g / 255.;
let b = b / 255.;
let c = Color::from_rgba_float(r, g, b, alpha);
Ok((input, c))
}
fn parse_percentage_rgb(input: &str) -> IResult<&str, Color> {
let (input, prefixed) = opt(alt((tag("rgb("), tag("rgba("))))(input)?;
let is_prefixed = prefixed.is_some();
let (input, _) = space0(input)?;
let (input, r) = parse_percentage(input)?;
let (input, _) = parse_separator(input)?;
let (input, g) = parse_percentage(input)?;
let (input, _) = parse_separator(input)?;
let (input, b) = parse_percentage(input)?;
let (input, alpha) = parse_alpha(input)?;
let (input, _) = space0(input)?;
let (input, _) = cond(is_prefixed, char(')'))(input)?;
let c = Color::from_rgba_float(r, g, b, alpha);
Ok((input, c))
}
fn parse_hsl(input: &str) -> IResult<&str, Color> {
let (input, _) = alt((tag("hsl("), tag("hsla(")))(input)?;
let (input, _) = space0(input)?;
let (input, h) = parse_angle(input)?;
let (input, _) = parse_separator(input)?;
let (input, s) = parse_percentage(input)?;
let (input, _) = parse_separator(input)?;
let (input, l) = parse_percentage(input)?;
let (input, alpha) = parse_alpha(input)?;
let (input, _) = space0(input)?;
let (input, _) = char(')')(input)?;
let c = Color::from_hsla(h, s, l, alpha);
Ok((input, c))
}
fn parse_gray(input: &str) -> IResult<&str, Color> {
let (input, _) = tag("gray(")(input)?;
let (input, _) = space0(input)?;
let (input, g) = verify(alt((parse_percentage, double)), |&d| d >= 0.)(input)?;
let (input, _) = space0(input)?;
let (input, _) = char(')')(input)?;
let c = Color::from_rgb_float(g, g, g);
Ok((input, c))
}
fn parse_lab(input: &str) -> IResult<&str, Color> {
let (input, _) = opt(tag_no_case("cie"))(input)?;
let (input, _) = tag_no_case("lab(")(input)?;
let (input, _) = space0(input)?;
let (input, l) = double(input)?;
let (input, _) = parse_separator(input)?;
let (input, a) = double(input)?;
let (input, _) = parse_separator(input)?;
let (input, b) = double(input)?;
let (input, alpha) = parse_alpha(input)?;
let (input, _) = space0(input)?;
let (input, _) = char(')')(input)?;
let c = Color::from_lab(l, a, b, alpha);
Ok((input, c))
}
fn parse_named(input: &str) -> IResult<&str, Color> {
let (input, color) = all_consuming(alpha1)(input)?;
let nc = NAMED_COLORS
.iter()
.find(|nc| color.to_lowercase() == nc.name);
match nc {
None => Err(Err::Error(nom::error::Error::new(
"Couldn't find matching named color",
ErrorKind::Alpha,
))),
Some(nc) => Ok((input, nc.color.clone())),
}
}
pub fn parse_color(input: &str) -> Option<Color> {
alt((
all_consuming(parse_hex),
all_consuming(parse_numeric_rgb),
all_consuming(parse_percentage_rgb),
all_consuming(parse_hsl),
all_consuming(parse_gray),
all_consuming(parse_lab),
all_consuming(parse_named),
))(input.trim())
.ok()
.map(|(_, c)| c)
}
#[test]
fn parse_rgb_hex_syntax() {
assert_eq!(Some(rgb(255, 0, 153)), parse_color("f09"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("#f09"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("#F09"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("#ff0099"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("#FF0099"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("ff0099"));
assert_eq!(Some(rgb(87, 166, 206)), parse_color("57A6CE"));
assert_eq!(Some(rgb(255, 0, 119)), parse_color(" #ff0077 "));
assert_eq!(None, parse_color("#1"));
assert_eq!(None, parse_color("#12"));
assert_eq!(None, parse_color("#12345"));
assert_eq!(None, parse_color("#1234567"));
assert_eq!(None, parse_color("#hh0033"));
assert_eq!(None, parse_color("#h03"));
}
#[test]
fn parse_rgb_functional_syntax() {
assert_eq!(Some(rgb(255, 0, 153)), parse_color("rgb(255,0,153)"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("rgb(255, 0, 153)"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("rgb( 255 , 0 , 153 )"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("rgb(255, 0, 153.0)"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("rgb(255 0 153)"));
assert_eq!(
Some(rgb(255, 8, 119)),
parse_color(" rgb( 255 , 8 , 119 ) ")
);
assert_eq!(Some(rgb(255, 0, 127)), parse_color("rgb(100%,0%,49.8%)"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("rgb(100%,0%,60%)"));
assert_eq!(Some(rgb(255, 0, 119)), parse_color("rgb(100%,0%,46.7%)"));
assert_eq!(Some(rgb(3, 54, 119)), parse_color("rgb(1%,21.2%,46.7%)"));
assert_eq!(Some(rgb(255, 0, 119)), parse_color("rgb(255 0 119)"));
assert_eq!(
Some(rgb(255, 0, 119)),
parse_color("rgb( 255 0 119)")
);
assert_eq!(Some(rgb(255, 0, 153)), parse_color("rgb(100%,0%,60%)"));
assert_eq!(Some(rgb(255, 0, 153)), parse_color("rgb(100%, 0%, 60%)"));
assert_eq!(
Some(rgb(255, 0, 153)),
parse_color("rgb( 100% , 0% , 60% )")
);
assert_eq!(Some(rgb(255, 0, 153)), parse_color("rgb(100% 0% 60%)"));
assert_eq!(Some(rgb(100, 5, 1)), parse_color("rgb(1e2, .5e1, .5e0)"));
assert_eq!(Some(rgb(140, 0, 153)), parse_color("rgb(55% 0% 60%)"));
assert_eq!(Some(rgb(142, 0, 153)), parse_color("rgb(55.5% 0% 60%)"));
assert_eq!(Some(rgb(255, 0, 0)), parse_color("rgb(256,0,0)"));
assert_eq!(Some(rgb(255, 255, 0)), parse_color("rgb(100%,100%,-45%)"));
assert_eq!(None, parse_color("rgb(255,0)"));
assert_eq!(None, parse_color("rgb(255,0,0"));
assert_eq!(None, parse_color("rgb (256,0,0)"));
assert_eq!(None, parse_color("rgb(100%,0,0)"));
assert_eq!(None, parse_color("rgb(2550119)"));
}
#[test]
fn parse_rgb_standalone_syntax() {
assert_eq!(
Some(rgb(255, 8, 119)),
parse_color(" rgb( 255 , 8 , 119 ) ")
);
assert_eq!(rgb(255, 0, 153), parse_color("255,0,153").unwrap());
assert_eq!(rgb(255, 0, 153), parse_color("255, 0, 153").unwrap());
assert_eq!(
rgb(255, 0, 153),
parse_color(" 255 , 0 , 153 ").unwrap()
);
assert_eq!(rgb(255, 0, 153), parse_color("255 0 153").unwrap());
assert_eq!(rgb(255, 0, 153), parse_color("255 0 153.0").unwrap());
assert_eq!(Some(rgb(1, 2, 3)), parse_color("1,2,3"));
}
#[test]
fn parse_hsl_syntax() {
assert_eq!(
Some(Color::from_hsl(280.0, 0.2, 0.5)),
parse_color("hsl(280,20%,50%)")
);
assert_eq!(
Some(Color::from_hsl(280.0, 0.2, 0.5)),
parse_color("hsl(280deg,20%,50%)")
);
assert_eq!(
Some(Color::from_hsl(280.0, 0.2, 0.5)),
parse_color("hsl(280°,20%,50%)")
);
assert_eq!(
Some(Color::from_hsl(280.33, 0.123, 0.456)),
parse_color("hsl(280.33001,12.3%,45.6%)")
);
assert_eq!(
Some(Color::from_hsl(280.0, 0.2, 0.5)),
parse_color("hsl( 280 , 20% , 50%)")
);
assert_eq!(
Some(Color::from_hsl(270.0, 0.6, 0.7)),
parse_color("hsl(270 60% 70%)")
);
assert_eq!(
Some(Color::from_hsl(-140.0, 0.2, 0.5)),
parse_color("hsl(-140°,20%,50%)")
);
assert_eq!(
Some(Color::from_hsl(90.0, 0.2, 0.5)),
parse_color("hsl(100grad,20%,50%)")
);
assert_eq!(
Some(Color::from_hsl(90.05, 0.2, 0.5)),
parse_color("hsl(1.5708rad,20%,50%)")
);
assert_eq!(
Some(Color::from_hsl(90.0, 0.2, 0.5)),
parse_color("hsl(0.25turn,20%,50%)")
);
assert_eq!(
Some(Color::from_hsl(45.0, 0.2, 0.5)),
parse_color("hsl(50grad,20%,50%)")
);
assert_eq!(
Some(Color::from_hsl(45.0, 0.2, 0.5)),
parse_color("hsl(0.7854rad,20%,50%)")
);
assert_eq!(
Some(Color::from_hsl(45.0, 0.2, 0.5)),
parse_color("hsl(0.125turn,20%,50%)")
);
assert_eq!(None, parse_color("hsl(280,20%,50)"));
assert_eq!(None, parse_color("hsl(280,20,50%)"));
assert_eq!(None, parse_color("hsl(280%,20%,50%)"));
assert_eq!(None, parse_color("hsl(280,20%)"));
}
#[test]
fn parse_gray_syntax() {
assert_eq!(Some(Color::graytone(0.2)), parse_color("gray(0.2)"));
assert_eq!(Some(Color::black()), parse_color("gray(0.0)"));
assert_eq!(Some(Color::black()), parse_color("gray(0)"));
assert_eq!(Some(Color::white()), parse_color("gray(1.0)"));
assert_eq!(Some(Color::white()), parse_color("gray(1)"));
assert_eq!(Some(Color::white()), parse_color("gray(7.3)"));
assert_eq!(Some(Color::graytone(0.32)), parse_color("gray(.32)"));
assert_eq!(
Some(Color::graytone(0.41)),
parse_color(" gray( 0.41 ) ")
);
assert_eq!(Some(Color::graytone(0.2)), parse_color("gray(20%)"));
assert_eq!(Some(Color::black()), parse_color("gray(0%)"));
assert_eq!(Some(Color::black()), parse_color("gray(0.0%)"));
assert_eq!(Some(Color::white()), parse_color("gray(100%)"));
assert_eq!(Some(Color::graytone(0.5)), parse_color("gray(50%)"));
assert_eq!(None, parse_color("gray(-1)"));
assert_eq!(None, parse_color("gray(-1%)"));
assert_eq!(None, parse_color("gray(-4.%)"));
}
#[test]
fn parse_lab_syntax() {
assert_eq!(
Some(Color::from_lab(12.43, -35.5, 43.4, 1.0)),
parse_color("Lab(12.43,-35.5,43.4)")
);
assert_eq!(
Some(Color::from_lab(15.0, -23.0, 43.0, 0.5)),
parse_color("lab(15,-23,43,0.5)")
);
assert_eq!(
Some(Color::from_lab(15.0, 23.0, -43.0, 1.0)),
parse_color("CIELab(15,23,-43)")
);
assert_eq!(
Some(Color::from_lab(15.0, 35.5, -43.4, 1.0)),
parse_color("CIELab(15,35.5,-43.4)")
);
assert_eq!(
Some(Color::from_lab(15.0, -35.5, -43.4, 0.4)),
parse_color("cieLab(15,-35.5,-43.4,0.4)")
);
assert_eq!(
Some(Color::from_lab(15.0, 23.0, -43.0, 1.0)),
parse_color("Lab( 15, 23,-43 )")
);
assert_eq!(
Some(Color::from_lab(15.0, -35.5, -43.4, 0.4)),
parse_color("CieLab(15,-35.5,-43.4,0.4)")
);
assert_eq!(
Some(Color::from_lab(15.0, 23.0, -43.0, 1.0)),
parse_color("CIELab( 15, 23,-43 )")
);
}
#[test]
fn parse_named_syntax() {
assert_eq!(Some(Color::black()), parse_color("black"));
assert_eq!(Some(Color::blue()), parse_color("blue"));
assert_eq!(Some(Color::blue()), parse_color("Blue"));
assert_eq!(Some(Color::blue()), parse_color("BLUE"));
assert_eq!(Some(rgb(255, 20, 147)), parse_color("deeppink"));
assert_eq!(None, parse_color("whatever"));
assert_eq!(None, parse_color("red blue"));
}
#[test]
fn parse_alpha_syntax() {
assert_eq!(Some(rgba(255, 0, 0, 1.0)), parse_color("ff0000ff"));
assert_eq!(Some(rgba(255, 0, 0, 1.0)), parse_color("#ff0000ff"));
assert_eq!(Some(rgba(10, 0, 0, 1.0)), parse_color("rgb(10,0,0,1)"));
assert_eq!(Some(rgba(10, 0, 0, 1.0)), parse_color("rgb(10,0,0, 1)"));
assert_eq!(Some(rgba(10, 0, 0, 1.0)), parse_color("rgba(10,0,0,1)"));
assert_eq!(Some(rgba(10, 0, 0, 1.0)), parse_color("rgba(10,0,0, 1)"));
assert_eq!(Some(rgba(10, 0, 0, 1.0)), parse_color("rgba(10,0,0,1.0)"));
assert_eq!(Some(rgba(10, 0, 0, 1.0)), parse_color("rgba(10,0,0, 1.0)"));
assert_eq!(
Some(Color::from_hsla(10.0, 0.5, 0.5, 1.0)),
parse_color("hsl(10,50%,50%,1)")
);
assert_eq!(
Some(Color::from_hsla(10.0, 0.5, 0.5, 1.0)),
parse_color("hsl(10,50%,50%,1.0)")
);
assert_eq!(
Some(Color::from_hsla(10.0, 0.5, 0.5, 1.0)),
parse_color("hsla(10,50%,50%,1)")
);
assert_eq!(
Some(Color::from_hsla(10.0, 0.5, 0.5, 1.0)),
parse_color("hsla(10,50%,50%,1.0)")
);
assert_eq!(
Some(Color::from_lab(10.0, 30.0, 50.0, 1.0)),
parse_color("lab(10,30,50,1)")
);
assert_eq!(
Some(Color::from_lab(10.0, 30.0, 50.0, 1.0)),
parse_color("lab(10,30,50,1.0)")
);
assert_eq!(Some(rgba(10, 0, 0, 0.5)), parse_color("rgba(10,0,0,0.5)"));
assert_eq!(Some(rgba(10, 0, 0, 0.5)), parse_color("rgba(10,0,0,50%)"));
assert_eq!(Some(rgba(10, 0, 0, 0.33)), parse_color("rgba(10,0,0,0.33)"));
assert_eq!(Some(rgba(10, 0, 0, 0.33)), parse_color("rgba(10,0,0,33%)"));
assert_eq!(
format!("{:?}", Some(rgba(10, 0, 0, 0.502))),
format!("{:?}", parse_color("0a000080"))
);
assert_eq!(
format!("{:?}", Some(rgba(10, 0, 0, 0.329))),
format!("{:?}", parse_color("0a000054"))
);
}