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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */
//! Specified time values.
use crate::parser::{Parse, ParserContext};
use crate::values::computed::time::Time as ComputedTime;
use crate::values::computed::{Context, ToComputedValue};
use crate::values::specified::calc::CalcNode;
use crate::values::CSSFloat;
use crate::Zero;
use cssparser::{Parser, Token};
use std::fmt::{self, Write};
use style_traits::values::specified::AllowedNumericType;
use style_traits::{CssWriter, ParseError, SpecifiedValueInfo, StyleParseErrorKind, ToCss};
/// A time value according to CSS-VALUES § 6.2.
#[derive(Clone, Copy, Debug, MallocSizeOf, PartialEq, ToShmem)]
pub struct Time {
seconds: CSSFloat,
unit: TimeUnit,
calc_clamping_mode: Option<AllowedNumericType>,
}
/// A time unit.
#[derive(Clone, Copy, Debug, Eq, MallocSizeOf, PartialEq, ToShmem)]
pub enum TimeUnit {
/// `s`
Second,
/// `ms`
Millisecond,
}
impl Time {
/// Returns a time value that represents `seconds` seconds.
pub fn from_seconds_with_calc_clamping_mode(
seconds: CSSFloat,
calc_clamping_mode: Option<AllowedNumericType>,
) -> Self {
Time {
seconds,
unit: TimeUnit::Second,
calc_clamping_mode,
}
}
/// Returns a time value that represents `seconds` seconds.
pub fn from_seconds(seconds: CSSFloat) -> Self {
Self::from_seconds_with_calc_clamping_mode(seconds, None)
}
/// Returns the time in fractional seconds.
pub fn seconds(self) -> CSSFloat {
self.seconds
}
/// Returns the unit of the time.
#[inline]
pub fn unit(&self) -> &'static str {
match self.unit {
TimeUnit::Second => "s",
TimeUnit::Millisecond => "ms",
}
}
#[inline]
fn unitless_value(&self) -> CSSFloat {
match self.unit {
TimeUnit::Second => self.seconds,
TimeUnit::Millisecond => self.seconds * 1000.,
}
}
/// Parses a time according to CSS-VALUES § 6.2.
pub fn parse_dimension(value: CSSFloat, unit: &str) -> Result<Time, ()> {
let (seconds, unit) = match_ignore_ascii_case! { unit,
"s" => (value, TimeUnit::Second),
"ms" => (value / 1000.0, TimeUnit::Millisecond),
_ => return Err(())
};
Ok(Time {
seconds,
unit,
calc_clamping_mode: None,
})
}
fn parse_with_clamping_mode<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
clamping_mode: AllowedNumericType,
) -> Result<Self, ParseError<'i>> {
use style_traits::ParsingMode;
let location = input.current_source_location();
match *input.next()? {
// Note that we generally pass ParserContext to is_ok() to check
// that the ParserMode of the ParserContext allows all numeric
// values for SMIL regardless of clamping_mode, but in this Time
// value case, the value does not animate for SMIL at all, so we use
// ParsingMode::DEFAULT directly.
Token::Dimension {
value, ref unit, ..
} if clamping_mode.is_ok(ParsingMode::DEFAULT, value) => {
Time::parse_dimension(value, unit)
.map_err(|()| location.new_custom_error(StyleParseErrorKind::UnspecifiedError))
},
Token::Function(ref name) => {
let function = CalcNode::math_function(context, name, location)?;
CalcNode::parse_time(context, input, clamping_mode, function)
},
ref t => return Err(location.new_unexpected_token_error(t.clone())),
}
}
/// Parses a non-negative time value.
pub fn parse_non_negative<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
Self::parse_with_clamping_mode(context, input, AllowedNumericType::NonNegative)
}
}
impl Zero for Time {
#[inline]
fn zero() -> Self {
Self::from_seconds(0.0)
}
#[inline]
fn is_zero(&self) -> bool {
// The unit doesn't matter, i.e. `s` and `ms` are the same for zero.
self.seconds == 0.0 && self.calc_clamping_mode.is_none()
}
}
impl ToComputedValue for Time {
type ComputedValue = ComputedTime;
fn to_computed_value(&self, _context: &Context) -> Self::ComputedValue {
let seconds = self
.calc_clamping_mode
.map_or(self.seconds(), |mode| mode.clamp(self.seconds()));
ComputedTime::from_seconds(crate::values::normalize(seconds))
}
fn from_computed_value(computed: &Self::ComputedValue) -> Self {
Time {
seconds: computed.seconds(),
unit: TimeUnit::Second,
calc_clamping_mode: None,
}
}
}
impl Parse for Time {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
Self::parse_with_clamping_mode(context, input, AllowedNumericType::All)
}
}
impl ToCss for Time {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
crate::values::serialize_specified_dimension(
self.unitless_value(),
self.unit(),
self.calc_clamping_mode.is_some(),
dest,
)
}
}
impl SpecifiedValueInfo for Time {}