use nom::branch::alt;
use nom::bytes::complete::tag;
use nom::character::complete::anychar;
use nom::combinator::map;
use nom::combinator::peek;
use nom::combinator::recognize;
use nom::combinator::verify;
use nom::multi::many_till;

use super::object::PlainText;
use super::radio_link::RematchObject;
use super::Context;
use super::Object;
use crate::error::Res;
use crate::parser::object_parser::any_object_except_plain_text;
use crate::parser::parser_with_context::parser_with_context;
use crate::parser::util::exit_matcher_parser;

#[tracing::instrument(ret, level = "debug")]
pub fn plain_text<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, PlainText<'s>> {
    let (remaining, source) = recognize(verify(
        many_till(
            anychar,
            peek(alt((
                parser_with_context!(exit_matcher_parser)(context),
                parser_with_context!(plain_text_end)(context),
            ))),
        ),
        |(children, _exit_contents)| !children.is_empty(),
    ))(input)?;

    Ok((remaining, PlainText { source }))
}

#[tracing::instrument(ret, level = "debug")]
fn plain_text_end<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, &'s str> {
    recognize(parser_with_context!(any_object_except_plain_text)(context))(input)
}

impl<'x> RematchObject<'x> for PlainText<'x> {
    #[tracing::instrument(ret, level = "debug")]
    fn rematch_object<'r, 's>(
        &'x self,
        _context: Context<'r, 's>,
        input: &'s str,
    ) -> Res<&'s str, Object<'s>> {
        map(tag(self.source), |s| {
            Object::PlainText(PlainText { source: s })
        })(input)
    }
}

#[cfg(test)]
mod tests {
    use nom::combinator::map;

    use super::*;
    use crate::parser::parser_context::ContextElement;
    use crate::parser::parser_context::ContextTree;
    use crate::parser::parser_with_context::parser_with_context;
    use crate::parser::source::Source;

    #[test]
    fn plain_text_simple() {
        let input = "foobarbaz";
        let initial_context: ContextTree<'_, '_> = ContextTree::new();
        let document_context =
            initial_context.with_additional_node(ContextElement::DocumentRoot(input));
        let plain_text_matcher = parser_with_context!(plain_text)(&document_context);
        let (remaining, result) = map(plain_text_matcher, Object::PlainText)(input).unwrap();
        assert_eq!(remaining, "");
        assert_eq!(result.get_source(), input);
    }
}