/* 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 http://mozilla.org/MPL/2.0/. */
//! The generated content assignment phase.
//!
//! This phase handles CSS counters, quotes, and ordered lists per CSS § 12.3-12.5. It cannot be
//! done in parallel and is therefore a sequential pass that runs on as little of the flow tree
//! as possible.
use context::{LayoutContext, with_thread_local_font_context};
use flow::{Flow, FlowFlags, GetBaseFlow, ImmutableFlowUtils};
use fragment::{Fragment, GeneratedContentInfo, SpecificFragmentInfo, UnscannedTextFragmentInfo};
use gfx::display_list::OpaqueNode;
use script_layout_interface::wrapper_traits::PseudoElementType;
use smallvec::SmallVec;
use std::collections::{HashMap, LinkedList};
use style::computed_values::display::T as Display;
use style::computed_values::list_style_type::T as ListStyleType;
use style::properties::ComputedValues;
use style::selector_parser::RestyleDamage;
use style::servo::restyle_damage::ServoRestyleDamage;
use style::values::computed::counters::ContentItem;
use text::TextRunScanner;
use traversal::InorderFlowTraversal;
// Decimal styles per CSS-COUNTER-STYLES § 6.1:
static DECIMAL: [char; 10] = [ '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' ];
// TODO(pcwalton): `decimal-leading-zero`
static ARABIC_INDIC: [char; 10] = [ '٠', '١', '٢', '٣', '٤', '٥', '٦', '٧', '٨', '٩' ];
// TODO(pcwalton): `armenian`, `upper-armenian`, `lower-armenian`
static BENGALI: [char; 10] = [ '০', '১', '২', '৩', '৪', '৫', '৬', '৭', '৮', '৯' ];
static CAMBODIAN: [char; 10] = [ '០', '១', '២', '៣', '៤', '៥', '៦', '៧', '៨', '៩' ];
// TODO(pcwalton): Suffix for CJK decimal.
static CJK_DECIMAL: [char; 10] = [ '〇', '一', '二', '三', '四', '五', '六', '七', '八', '九' ];
static DEVANAGARI: [char; 10] = [ '०', '१', '२', '३', '४', '५', '६', '७', '८', '९' ];
// TODO(pcwalton): `georgian`
static GUJARATI: [char; 10] = ['૦', '૧', '૨', '૩', '૪', '૫', '૬', '૭', '૮', '૯'];
static GURMUKHI: [char; 10] = ['੦', '੧', '੨', '੩', '੪', '੫', '੬', '੭', '੮', '੯'];
// TODO(pcwalton): `hebrew`
static KANNADA: [char; 10] = ['೦', '೧', '೨', '೩', '೪', '೫', '೬', '೭', '೮', '೯'];
static LAO: [char; 10] = ['໐', '໑', '໒', '໓', '໔', '໕', '໖', '໗', '໘', '໙'];
static MALAYALAM: [char; 10] = ['൦', '൧', '൨', '൩', '൪', '൫', '൬', '൭', '൮', '൯'];
static MONGOLIAN: [char; 10] = ['᠐', '᠑', '᠒', '᠓', '᠔', '᠕', '᠖', '᠗', '᠘', '᠙'];
static MYANMAR: [char; 10] = ['၀', '၁', '၂', '၃', '၄', '၅', '၆', '၇', '၈', '၉'];
static ORIYA: [char; 10] = ['୦', '୧', '୨', '୩', '୪', '୫', '୬', '୭', '୮', '୯'];
static PERSIAN: [char; 10] = ['۰', '۱', '۲', '۳', '۴', '۵', '۶', '۷', '۸', '۹'];
// TODO(pcwalton): `lower-roman`, `upper-roman`
static TELUGU: [char; 10] = ['౦', '౧', '౨', '౩', '౪', '౫', '౬', '౭', '౮', '౯'];
static THAI: [char; 10] = ['๐', '๑', '๒', '๓', '๔', '๕', '๖', '๗', '๘', '๙'];
static TIBETAN: [char; 10] = ['༠', '༡', '༢', '༣', '༤', '༥', '༦', '༧', '༨', '༩'];
// Alphabetic styles per CSS-COUNTER-STYLES § 6.2:
static LOWER_ALPHA: [char; 26] = [
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's',
't', 'u', 'v', 'w', 'x', 'y', 'z'
];
static UPPER_ALPHA: [char; 26] = [
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S',
'T', 'U', 'V', 'W', 'X', 'Y', 'Z'
];
static CJK_EARTHLY_BRANCH: [char; 12] = [
'子', '丑', '寅', '卯', '辰', '巳', '午', '未', '申', '酉', '戌', '亥'
];
static CJK_HEAVENLY_STEM: [char; 10] = [
'甲', '乙', '丙', '丁', '戊', '己', '庚', '辛', '壬', '癸'
];
static LOWER_GREEK: [char; 24] = [
'α', 'β', 'γ', 'δ', 'ε', 'ζ', 'η', 'θ', 'ι', 'κ', 'λ', 'μ', 'ν', 'ξ', 'ο', 'π', 'ρ', 'σ', 'τ',
'υ', 'φ', 'χ', 'ψ', 'ω'
];
static HIRAGANA: [char; 48] = [
'あ', 'い', 'う', 'え', 'お', 'か', 'き', 'く', 'け', 'こ', 'さ', 'し', 'す', 'せ', 'そ',
'た', 'ち', 'つ', 'て', 'と', 'な', 'に', 'ぬ', 'ね', 'の', 'は', 'ひ', 'ふ', 'へ', 'ほ',
'ま', 'み', 'む', 'め', 'も', 'や', 'ゆ', 'よ', 'ら', 'り', 'る', 'れ', 'ろ',
'わ', 'ゐ', 'ゑ', 'を', 'ん'
];
static HIRAGANA_IROHA: [char; 47] = [
'い', 'ろ', 'は', 'に', 'ほ', 'へ', 'と', 'ち', 'り', 'ぬ', 'る', 'を', 'わ', 'か', 'よ',
'た', 'れ', 'そ', 'つ', 'ね', 'な', 'ら', 'む', 'う', 'ゐ', 'の', 'お', 'く', 'や', 'ま',
'け', 'ふ', 'こ', 'え', 'て', 'あ', 'さ', 'き', 'ゆ', 'め', 'み', 'し', 'ゑ',
'ひ', 'も', 'せ', 'す'
];
static KATAKANA: [char; 48] = [
'ア', 'イ', 'ウ', 'エ', 'オ', 'カ', 'キ', 'ク', 'ケ', 'コ', 'サ', 'シ', 'ス', 'セ', 'ソ',
'タ', 'チ', 'ツ', 'テ', 'ト', 'ナ', 'ニ', 'ヌ', 'ネ', 'ノ', 'ハ', 'ヒ', 'フ', 'ヘ', 'ホ',
'マ', 'ミ', 'ム', 'メ', 'モ', 'ヤ', 'ユ', 'ヨ', 'ラ', 'リ', 'ル', 'レ', 'ロ',
'ワ', 'ヰ', 'ヱ', 'ヲ', 'ン'
];
static KATAKANA_IROHA: [char; 47] = [
'イ', 'ロ', 'ハ', 'ニ', 'ホ', 'ヘ', 'ト', 'チ', 'リ', 'ヌ', 'ル', 'ヲ', 'ワ', 'カ', 'ヨ',
'タ', 'レ', 'ソ', 'ツ', 'ネ', 'ナ', 'ラ', 'ム', 'ウ', 'ヰ', 'ノ', 'オ', 'ク', 'ヤ', 'マ',
'ケ', 'フ', 'コ', 'エ', 'テ', 'ア', 'サ', 'キ', 'ユ', 'メ', 'ミ', 'シ', 'ヱ',
'ヒ', 'モ', 'セ', 'ス'
];
/// The generated content resolution traversal.
pub struct ResolveGeneratedContent<'a> {
/// The layout context.
layout_context: &'a LayoutContext<'a>,
/// The counter representing an ordered list item.
list_item: Counter,
/// Named CSS counters.
counters: HashMap<String, Counter>,
/// The level of quote nesting.
quote: u32,
}
impl<'a> ResolveGeneratedContent<'a> {
/// Creates a new generated content resolution traversal.
pub fn new(layout_context: &'a LayoutContext) -> ResolveGeneratedContent<'a> {
ResolveGeneratedContent {
layout_context: layout_context,
list_item: Counter::new(),
counters: HashMap::new(),
quote: 0,
}
}
}
impl<'a> InorderFlowTraversal for ResolveGeneratedContent<'a> {
#[inline]
fn process(&mut self, flow: &mut Flow, level: u32) {
let mut mutator = ResolveGeneratedContentFragmentMutator {
traversal: self,
level: level,
is_block: flow.is_block_like(),
incremented: false,
};
flow.mutate_fragments(&mut |fragment| mutator.mutate_fragment(fragment))
}
#[inline]
fn should_process_subtree(&mut self, flow: &mut Flow) -> bool {
flow.base().restyle_damage.intersects(ServoRestyleDamage::RESOLVE_GENERATED_CONTENT) ||
flow.base().flags.intersects(FlowFlags::AFFECTS_COUNTERS | FlowFlags::HAS_COUNTER_AFFECTING_CHILDREN)
}
}
/// The object that mutates the generated content fragments.
struct ResolveGeneratedContentFragmentMutator<'a, 'b: 'a> {
/// The traversal.
traversal: &'a mut ResolveGeneratedContent<'b>,
/// The level we're at in the flow tree.
level: u32,
/// Whether this flow is a block flow.
is_block: bool,
/// Whether we've incremented the counter yet.
incremented: bool,
}
impl<'a, 'b> ResolveGeneratedContentFragmentMutator<'a, 'b> {
fn mutate_fragment(&mut self, fragment: &mut Fragment) {
// We only reset and/or increment counters once per flow. This avoids double-incrementing
// counters on list items (once for the main fragment and once for the marker).
if !self.incremented {
self.reset_and_increment_counters_as_necessary(fragment);
}
let mut list_style_type = fragment.style().get_list().list_style_type;
if fragment.style().get_box().display != Display::ListItem {
list_style_type = ListStyleType::None
}
let mut new_info = None;
{
let info =
if let SpecificFragmentInfo::GeneratedContent(ref mut info) = fragment.specific {
info
} else {
return
};
match **info {
GeneratedContentInfo::ListItem => {
new_info = self.traversal.list_item.render(self.traversal.layout_context,
fragment.node,
fragment.pseudo.clone(),
fragment.style.clone(),
list_style_type,
RenderingMode::Suffix(".\u{00a0}"))
}
GeneratedContentInfo::Empty |
GeneratedContentInfo::ContentItem(ContentItem::String(_)) => {
// Nothing to do here.
}
GeneratedContentInfo::ContentItem(ContentItem::Counter(ref counter_name,
counter_style)) => {
let temporary_counter = Counter::new();
let counter = self.traversal
.counters
.get(&*counter_name.0)
.unwrap_or(&temporary_counter);
new_info = counter.render(self.traversal.layout_context,
fragment.node,
fragment.pseudo.clone(),
fragment.style.clone(),
counter_style,
RenderingMode::Plain)
}
GeneratedContentInfo::ContentItem(ContentItem::Counters(ref counter_name,
ref separator,
counter_style)) => {
let temporary_counter = Counter::new();
let counter = self.traversal
.counters
.get(&*counter_name.0)
.unwrap_or(&temporary_counter);
new_info = counter.render(self.traversal.layout_context,
fragment.node,
fragment.pseudo,
fragment.style.clone(),
counter_style,
RenderingMode::All(&separator));
}
GeneratedContentInfo::ContentItem(ContentItem::OpenQuote) => {
new_info = render_text(self.traversal.layout_context,
fragment.node,
fragment.pseudo,
fragment.style.clone(),
self.quote(&*fragment.style, false));
self.traversal.quote += 1
}
GeneratedContentInfo::ContentItem(ContentItem::CloseQuote) => {
if self.traversal.quote >= 1 {
self.traversal.quote -= 1
}
new_info = render_text(self.traversal.layout_context,
fragment.node,
fragment.pseudo,
fragment.style.clone(),
self.quote(&*fragment.style, true));
}
GeneratedContentInfo::ContentItem(ContentItem::NoOpenQuote) => {
self.traversal.quote += 1
}
GeneratedContentInfo::ContentItem(ContentItem::NoCloseQuote) => {
if self.traversal.quote >= 1 {
self.traversal.quote -= 1
}
}
}
};
fragment.specific = match new_info {
Some(new_info) => new_info,
// If the fragment did not generate any content, replace it with a no-op placeholder
// so that it isn't processed again on the next layout. FIXME (mbrubeck): When
// processing an inline flow, this traversal should be allowed to insert or remove
// fragments. Then we can just remove these fragments rather than adding placeholders.
None => SpecificFragmentInfo::GeneratedContent(Box::new(GeneratedContentInfo::Empty))
};
}
fn reset_and_increment_counters_as_necessary(&mut self, fragment: &mut Fragment) {
let mut list_style_type = fragment.style().get_list().list_style_type;
if !self.is_block || fragment.style().get_box().display != Display::ListItem {
list_style_type = ListStyleType::None
}
match list_style_type {
ListStyleType::Disc | ListStyleType::None | ListStyleType::Circle |
ListStyleType::Square | ListStyleType::DisclosureOpen |
ListStyleType::DisclosureClosed => {}
_ => self.traversal.list_item.increment(self.level, 1),
}
// Truncate down counters.
for (_, counter) in &mut self.traversal.counters {
counter.truncate_to_level(self.level);
}
self.traversal.list_item.truncate_to_level(self.level);
for &(ref counter_name, value) in &*fragment.style().get_counters().counter_reset {
let counter_name = &*counter_name.0;
if let Some(ref mut counter) = self.traversal.counters.get_mut(counter_name) {
counter.reset(self.level, value);
continue
}
let mut counter = Counter::new();
counter.reset(self.level, value);
self.traversal.counters.insert(counter_name.to_owned(), counter);
}
for &(ref counter_name, value) in &*fragment.style().get_counters().counter_increment {
let counter_name = &*counter_name.0;
if let Some(ref mut counter) = self.traversal.counters.get_mut(counter_name) {
counter.increment(self.level, value);
continue
}
let mut counter = Counter::new();
counter.increment(self.level, value);
self.traversal.counters.insert(counter_name.to_owned(), counter);
}
self.incremented = true
}
fn quote(&self, style: &ComputedValues, close: bool) -> String {
let quotes = &style.get_list().quotes;
if quotes.0.is_empty() {
return String::new()
}
let &(ref open_quote, ref close_quote) =
if self.traversal.quote as usize >= quotes.0.len() {
quotes.0.last().unwrap()
} else {
"es.0[self.traversal.quote as usize]
};
if close {
close_quote.to_string()
} else {
open_quote.to_string()
}
}
}
/// A counter per CSS 2.1 § 12.4.
struct Counter {
/// The values at each level.
values: Vec<CounterValue>,
}
impl Counter {
fn new() -> Counter {
Counter {
values: Vec::new(),
}
}
fn reset(&mut self, level: u32, value: i32) {
// Do we have an instance of the counter at this level? If so, just mutate it.
if let Some(ref mut existing_value) = self.values.last_mut() {
if level == existing_value.level {
existing_value.value = value;
return
}
}
// Otherwise, push a new instance of the counter.
self.values.push(CounterValue {
level: level,
value: value,
})
}
fn truncate_to_level(&mut self, level: u32) {
if let Some(position) = self.values.iter().position(|value| value.level > level) {
self.values.truncate(position)
}
}
fn increment(&mut self, level: u32, amount: i32) {
if let Some(ref mut value) = self.values.last_mut() {
value.value += amount;
return
}
self.values.push(CounterValue {
level: level,
value: amount,
})
}
fn render(&self,
layout_context: &LayoutContext,
node: OpaqueNode,
pseudo: PseudoElementType,
style: ::ServoArc<ComputedValues>,
list_style_type: ListStyleType,
mode: RenderingMode)
-> Option<SpecificFragmentInfo> {
let mut string = String::new();
match mode {
RenderingMode::Plain => {
let value = match self.values.last() {
Some(ref value) => value.value,
None => 0,
};
push_representation(value, list_style_type, &mut string)
}
RenderingMode::Suffix(suffix) => {
let value = match self.values.last() {
Some(ref value) => value.value,
None => 0,
};
push_representation(value, list_style_type, &mut string);
string.push_str(suffix)
}
RenderingMode::All(separator) => {
let mut first = true;
for value in &self.values {
if !first {
string.push_str(separator)
}
first = false;
push_representation(value.value, list_style_type, &mut string)
}
}
}
if string.is_empty() {
None
} else {
render_text(layout_context, node, pseudo, style, string)
}
}
}
/// How a counter value is to be rendered.
enum RenderingMode<'a> {
/// The innermost counter value is rendered with no extra decoration.
Plain,
/// The innermost counter value is rendered with the given string suffix.
Suffix(&'a str),
/// All values of the counter are rendered with the given separator string between them.
All(&'a str),
}
/// The value of a counter at a given level.
struct CounterValue {
/// The level of the flow tree that this corresponds to.
level: u32,
/// The value of the counter at this level.
value: i32,
}
/// Creates fragment info for a literal string.
fn render_text(layout_context: &LayoutContext,
node: OpaqueNode,
pseudo: PseudoElementType,
style: ::ServoArc<ComputedValues>,
string: String)
-> Option<SpecificFragmentInfo> {
let mut fragments = LinkedList::new();
let info = SpecificFragmentInfo::UnscannedText(
Box::new(UnscannedTextFragmentInfo::new(string.into_boxed_str(), None))
);
fragments.push_back(Fragment::from_opaque_node_and_style(node,
pseudo,
style.clone(),
style,
RestyleDamage::rebuild_and_reflow(),
info));
// FIXME(pcwalton): This should properly handle multiple marker fragments. This could happen
// due to text run splitting.
let fragments = with_thread_local_font_context(layout_context, |font_context| {
TextRunScanner::new().scan_for_runs(font_context, fragments)
});
if fragments.is_empty() {
None
} else {
Some(fragments.fragments.into_iter().next().unwrap().specific)
}
}
/// Appends string that represents the value rendered using the system appropriate for the given
/// `list-style-type` onto the given string.
fn push_representation(value: i32, list_style_type: ListStyleType, accumulator: &mut String) {
match list_style_type {
ListStyleType::None => {}
ListStyleType::Disc |
ListStyleType::Circle |
ListStyleType::Square |
ListStyleType::DisclosureOpen |
ListStyleType::DisclosureClosed => {
accumulator.push(static_representation(list_style_type))
}
ListStyleType::Decimal => push_numeric_representation(value, &DECIMAL, accumulator),
ListStyleType::ArabicIndic => {
push_numeric_representation(value, &ARABIC_INDIC, accumulator)
}
ListStyleType::Bengali => push_numeric_representation(value, &BENGALI, accumulator),
ListStyleType::Cambodian |
ListStyleType::Khmer => {
push_numeric_representation(value, &CAMBODIAN, accumulator)
}
ListStyleType::CjkDecimal => {
push_numeric_representation(value, &CJK_DECIMAL, accumulator)
}
ListStyleType::Devanagari => {
push_numeric_representation(value, &DEVANAGARI, accumulator)
}
ListStyleType::Gujarati => push_numeric_representation(value, &GUJARATI, accumulator),
ListStyleType::Gurmukhi => push_numeric_representation(value, &GURMUKHI, accumulator),
ListStyleType::Kannada => push_numeric_representation(value, &KANNADA, accumulator),
ListStyleType::Lao => push_numeric_representation(value, &LAO, accumulator),
ListStyleType::Malayalam => {
push_numeric_representation(value, &MALAYALAM, accumulator)
}
ListStyleType::Mongolian => {
push_numeric_representation(value, &MONGOLIAN, accumulator)
}
ListStyleType::Myanmar => push_numeric_representation(value, &MYANMAR, accumulator),
ListStyleType::Oriya => push_numeric_representation(value, &ORIYA, accumulator),
ListStyleType::Persian => push_numeric_representation(value, &PERSIAN, accumulator),
ListStyleType::Telugu => push_numeric_representation(value, &TELUGU, accumulator),
ListStyleType::Thai => push_numeric_representation(value, &THAI, accumulator),
ListStyleType::Tibetan => push_numeric_representation(value, &TIBETAN, accumulator),
ListStyleType::LowerAlpha => {
push_alphabetic_representation(value, &LOWER_ALPHA, accumulator)
}
ListStyleType::UpperAlpha => {
push_alphabetic_representation(value, &UPPER_ALPHA, accumulator)
}
ListStyleType::CjkEarthlyBranch => {
push_alphabetic_representation(value, &CJK_EARTHLY_BRANCH, accumulator)
}
ListStyleType::CjkHeavenlyStem => {
push_alphabetic_representation(value, &CJK_HEAVENLY_STEM, accumulator)
}
ListStyleType::LowerGreek => {
push_alphabetic_representation(value, &LOWER_GREEK, accumulator)
}
ListStyleType::Hiragana => {
push_alphabetic_representation(value, &HIRAGANA, accumulator)
}
ListStyleType::HiraganaIroha => {
push_alphabetic_representation(value, &HIRAGANA_IROHA, accumulator)
}
ListStyleType::Katakana => {
push_alphabetic_representation(value, &KATAKANA, accumulator)
}
ListStyleType::KatakanaIroha => {
push_alphabetic_representation(value, &KATAKANA_IROHA, accumulator)
}
}
}
/// Returns the static character that represents the value rendered using the given list-style, if
/// possible.
pub fn static_representation(list_style_type: ListStyleType) -> char {
match list_style_type {
ListStyleType::Disc => '•',
ListStyleType::Circle => '◦',
ListStyleType::Square => '▪',
ListStyleType::DisclosureOpen => '▾',
ListStyleType::DisclosureClosed => '‣',
_ => panic!("No static representation for this list-style-type!"),
}
}
/// Pushes the string that represents the value rendered using the given *alphabetic system* onto
/// the accumulator per CSS-COUNTER-STYLES § 3.1.4.
fn push_alphabetic_representation(value: i32, system: &[char], accumulator: &mut String) {
let mut abs_value = handle_negative_value(value, accumulator);
let mut string: SmallVec<[char; 8]> = SmallVec::new();
while abs_value != 0 {
// Step 1.
abs_value = abs_value - 1;
// Step 2.
string.push(system[abs_value % system.len()]);
// Step 3.
abs_value = abs_value / system.len();
}
accumulator.extend(string.iter().cloned().rev())
}
/// Pushes the string that represents the value rendered using the given *numeric system* onto the
/// accumulator per CSS-COUNTER-STYLES § 3.1.5.
fn push_numeric_representation(value: i32, system: &[char], accumulator: &mut String) {
let mut abs_value = handle_negative_value(value, accumulator);
// Step 1.
if abs_value == 0 {
accumulator.push(system[0]);
return
}
// Step 2.
let mut string: SmallVec<[char; 8]> = SmallVec::new();
while abs_value != 0 {
// Step 2.1.
string.push(system[abs_value % system.len()]);
// Step 2.2.
abs_value = abs_value / system.len();
}
// Step 3.
accumulator.extend(string.iter().cloned().rev())
}
/// If the system uses a negative sign, handle negative values per CSS-COUNTER-STYLES § 2.
///
/// Returns the absolute value of the counter.
fn handle_negative_value(value: i32, accumulator: &mut String) -> usize {
// 3. If the counter value is negative and the counter style uses a negative sign, instead
// generate an initial representation using the absolute value of the counter value.
if value < 0 {
// TODO: Support different negative signs using the 'negative' descriptor.
// https://drafts.csswg.org/date/2015-07-16/css-counter-styles/#counter-style-negative
accumulator.push('-');
value.abs() as usize
} else {
value as usize
}
}