organic/src/parser/text_markup.rs

use nom::branch::alt;
use nom::bytes::complete::tag;

use super::Context;
use crate::error::CustomError;
use crate::error::MyError;
use crate::error::Res;
use crate::parser::util::get_one_before;
use crate::parser::TextMarkup;

#[tracing::instrument(ret, level = "debug")]
pub fn text_markup<'r, 's>(
    context: Context<'r, 's>,
    input: &'s str,
) -> Res<&'s str, TextMarkup<'s>> {
    let (remaining, _) = pre(context, input)?;
    let (remaining, open) = marker(remaining)?;
    return Err(nom::Err::Error(CustomError::MyError(MyError(
        "text markup not implemented yet.",
    ))));

    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 technically the beginning of a line.
        None | Some('\r') | Some('\n') | Some(' ') | Some('\t') | Some('-') | Some('(')
        | Some('{') | Some('\'') | Some('"') => {}
        Some(_) => {
            // Not at start of line, cannot be a heading
            return Err(nom::Err::Error(CustomError::MyError(MyError(
                "Not a valid pre character for text markup.",
            ))));
        }
    };
    Ok((input, ()))
}

#[tracing::instrument(ret, level = "debug")]
pub fn marker(input: &str) -> Res<&str, &str> {
    alt((tag("*"), tag("/"), tag("_"), tag("="), tag("~"), tag("+")))(input)
}