organic/src/parser/link.rs

use crate::parser::parser_with_context::parser_with_context;

use super::combinator::context_many_till;
use super::error::CustomError;
use super::error::MyError;
use super::error::Res;
use super::parser_context::ChainBehavior;
use super::parser_context::ContextElement;
use super::parser_context::ExitMatcherNode;
use super::text::symbol;
use super::text::text_element;
use super::token::Link;
use super::token::TextElement;
use super::util::in_section;
use super::Context;
use nom::combinator::map;
use nom::combinator::recognize;
use nom::sequence::tuple;

pub fn link<'r, 's>(context: Context<'r, 's>, i: &'s str) -> Res<&'s str, Link<'s>> {
    let link_start = parser_with_context!(context_link_start)(&context);
    let parser_context = context
        .with_additional_node(ContextElement::ExitMatcherNode(ExitMatcherNode {
            exit_matcher: ChainBehavior::AndParent(Some(&context_link_end)),
        }))
        .with_additional_node(ContextElement::Context("link"));
    let (remaining, captured) = recognize(tuple((link_start, |i| {
        context_many_till(&parser_context, text_element, context_link_end)(i)
    })))(i)?;
    let ret = Link { contents: captured };
    Ok((remaining, ret))
}

fn can_start_link<'r, 's>(context: Context<'r, 's>) -> bool {
    !in_section(context, "link")
}

fn context_link_start<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, &'s str> {
    if can_start_link(context) {
        recognize(link_start)(input)
    } else {
        // TODO: Make this a specific error instead of just a generic MyError
        return Err(nom::Err::Error(CustomError::MyError(MyError(
            "Cannot start link",
        ))));
    }
}

fn context_link_end<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, &'s str> {
    let (remaining, actual_match) = recognize(link_end)(input)?;
    Ok((remaining, actual_match))
}

fn link_start(input: &str) -> Res<&str, TextElement> {
    map(symbol("["), TextElement::Symbol)(input)
}

fn link_end(input: &str) -> Res<&str, TextElement> {
    map(symbol("]"), TextElement::Symbol)(input)
}