//! The string content type.
//!
//! **String** is a limited [text][] like content type which only allows
//! character escapes and character references.
//! It exists in things such as identifiers (media references, definitions),
//! titles, URLs, code (fenced) info and meta parts.
//!
//! The constructs found in string are:
//!
//! *   [Character escape][crate::construct::character_escape]
//! *   [Character reference][crate::construct::character_reference]
//!
//! [text]: crate::content::text

use crate::construct::{
    character_escape::start as character_escape, character_reference::start as character_reference,
    partial_data::start as data, partial_whitespace::whitespace,
};
use crate::tokenizer::{Code, State, Tokenizer};

const MARKERS: [Code; 5] = [
    Code::VirtualSpace, // `whitespace`
    Code::Char('\t'),   // `whitespace`
    Code::Char(' '),    // `hard_break_trailing`, `whitespace`
    Code::Char('&'),
    Code::Char('\\'),
];

/// Before string.
pub fn start(tokenizer: &mut Tokenizer) -> State {
    match tokenizer.current {
        Code::None => State::Ok,
        _ => tokenizer.attempt_n(
            vec![
                Box::new(character_reference),
                Box::new(character_escape),
                Box::new(whitespace),
            ],
            |ok| {
                let func = if ok { start } else { before_data };
                Box::new(func)
            },
        )(tokenizer),
    }
}

/// At data.
fn before_data(tokenizer: &mut Tokenizer) -> State {
    tokenizer.go(|t| data(t, &MARKERS), start)(tokenizer)
}