comrak 0.2.8

use pest::Parser;
use std::str;
use twoway::find_bytes;

#[cfg(debug_assertions)]
const _LEXER: &str = include_str!("lexer.pest");

#[derive(Parser)]
#[grammar = "lexer.pest"]
struct Lexer;

#[inline(always)]
fn search(rule: Rule, line: &[u8]) -> Option<usize> {
    if let Ok(pairs) = Lexer::parse(rule, unsafe { str::from_utf8_unchecked(line) }) {
        Some(pairs.last().unwrap().into_span().end())
    } else {
        None
    }
}
#[inline(always)]
fn is_match(rule: Rule, line: &[u8]) -> bool {
    Lexer::parse(rule, unsafe { str::from_utf8_unchecked(line) }).is_ok()
}

#[inline(always)]
pub fn atx_heading_start(line: &[u8]) -> Option<usize> {
    search(Rule::atx_heading_start, line)
}

#[inline(always)]
pub fn html_block_end_1(line: &[u8]) -> bool {
    find_bytes(line, b"</script>").is_some() || find_bytes(line, b"</pre>").is_some()
        || find_bytes(line, b"</style>").is_some()
}

#[inline(always)]
pub fn html_block_end_2(line: &[u8]) -> bool {
    find_bytes(line, b"-->").is_some()
}

#[inline(always)]
pub fn html_block_end_3(line: &[u8]) -> bool {
    find_bytes(line, b"?>").is_some()
}

#[inline(always)]
pub fn html_block_end_4(line: &[u8]) -> bool {
    line.contains(&b'>')
}

#[inline(always)]
pub fn html_block_end_5(line: &[u8]) -> bool {
    find_bytes(line, b"]]>").is_some()
}

#[inline(always)]
pub fn open_code_fence(line: &[u8]) -> Option<usize> {
    search(Rule::open_code_fence, line)
}

#[inline(always)]
pub fn close_code_fence(line: &[u8]) -> Option<usize> {
    search(Rule::close_code_fence, line)
}

#[inline(always)]
pub fn html_block_start(line: &[u8]) -> Option<usize> {
    lazy_static! {
        static ref STR2: &'static [u8] = b"<!--";
        static ref STR3: &'static [u8] = b"<?";
        static ref STR5: &'static [u8] = b"<![CDATA[";
    }

    if !line.starts_with(b"<") {
        return None;
    }

    if is_match(Rule::html_block_start_1, line) {
        Some(1)
    } else if line.starts_with(*STR2) {
        Some(2)
    } else if line.starts_with(*STR3) {
        Some(3)
    } else if is_match(Rule::html_block_start_4, line) {
        Some(4)
    } else if line.starts_with(*STR5) {
        Some(5)
    } else if is_match(Rule::html_block_start_6, line) {
        Some(6)
    } else {
        None
    }
}

#[inline(always)]
pub fn html_block_start_7(line: &[u8]) -> Option<usize> {
    if is_match(Rule::html_block_start_7, line) {
        Some(7)
    } else {
        None
    }
}

pub enum SetextChar {
    Equals,
    Hyphen,
}

#[inline(always)]
pub fn setext_heading_line(line: &[u8]) -> Option<SetextChar> {
    if is_match(Rule::setext_heading_line, line) {
        if line[0] == b'=' {
            Some(SetextChar::Equals)
        } else {
            Some(SetextChar::Hyphen)
        }
    } else {
        None
    }
}

#[inline(always)]
pub fn thematic_break(line: &[u8]) -> Option<usize> {
    search(Rule::thematic_break, line)
}

#[inline(always)]
pub fn footnote_definition(line: &[u8]) -> Option<usize> {
    search(Rule::footnote_definition, line)
}

#[inline(always)]
pub fn scheme(line: &[u8]) -> Option<usize> {
    search(Rule::scheme_rule, line)
}

#[inline(always)]
pub fn autolink_uri(line: &[u8]) -> Option<usize> {
    search(Rule::autolink_uri, line)
}

#[inline(always)]
pub fn autolink_email(line: &[u8]) -> Option<usize> {
    search(Rule::autolink_email, line)
}

#[inline(always)]
pub fn html_tag(line: &[u8]) -> Option<usize> {
    search(Rule::html_tag, line)
}

#[inline(always)]
pub fn spacechars(line: &[u8]) -> Option<usize> {
    search(Rule::spacechars, line)
}

#[inline(always)]
pub fn link_title(line: &[u8]) -> Option<usize> {
    search(Rule::link_title, line)
}

#[inline(always)]
pub fn table_start(line: &[u8]) -> Option<usize> {
    search(Rule::table_start, line)
}

#[inline(always)]
pub fn table_cell(line: &[u8]) -> Option<usize> {
    search(Rule::table_cell, line)
}

#[inline(always)]
pub fn table_cell_end(line: &[u8]) -> Option<usize> {
    search(Rule::table_cell_end, line)
}

#[inline(always)]
pub fn table_row_end(line: &[u8]) -> Option<usize> {
    search(Rule::table_row_end, line)
}