organic/src/parser/plain_link.rs

use nom::branch::alt;
use nom::character::complete::none_of;
use nom::combinator::eof;
use nom::combinator::recognize;

use super::Context;
use crate::error::CustomError;
use crate::error::MyError;
use crate::error::Res;
use crate::parser::object::PlainLink;
use crate::parser::util::get_one_before;
use crate::parser::util::not_yet_implemented;
use crate::parser::util::WORD_CONSTITUENT_CHARACTERS;

#[tracing::instrument(ret, level = "debug")]
pub fn plain_link<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, PlainLink<'s>> {
    not_yet_implemented()?;
    todo!();
}

#[tracing::instrument(ret, level = "debug")]
pub fn pre<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, ()> {
    let document_root = context.get_document_root().unwrap();
    let preceding_character = get_one_before(document_root, input)
        .map(|slice| slice.chars().next())
        .flatten();
    match preceding_character {
        // If None, we are at the start of the file which is fine
        None => {}
        Some(x) if !WORD_CONSTITUENT_CHARACTERS.contains(x) => {}
        Some(_) => {
            // Not at start of line, cannot be a heading
            return Err(nom::Err::Error(CustomError::MyError(MyError(
                "Not a valid pre character for plain link.",
            ))));
        }
    };
    Ok((input, ()))
}

#[tracing::instrument(ret, level = "debug")]
pub fn post<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, ()> {
    let (remaining, _) = alt((eof, recognize(none_of(WORD_CONSTITUENT_CHARACTERS))))(input)?;
    Ok((remaining, ()))
}