From 6822069c2f1fd65104c3534da01cd6c3a0ea0545 Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Wed, 19 Jul 2023 21:14:09 -0400
Subject: [PATCH] Implement the parser for anonymous footnotes.

---
 src/parser/footnote_reference.rs | 43 ++++++++++++++++++++++++++------
 src/parser/object.rs             |  2 +-
 2 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/src/parser/footnote_reference.rs b/src/parser/footnote_reference.rs
index 6d88df0..34c8428 100644
--- a/src/parser/footnote_reference.rs
+++ b/src/parser/footnote_reference.rs
@@ -1,14 +1,18 @@
 use nom::branch::alt;
 use nom::bytes::complete::tag;
 use nom::bytes::complete::tag_no_case;
+use nom::combinator::verify;
+use nom::multi::many_till;
 
 use super::parser_context::ContextElement;
 use super::Context;
 use crate::error::CustomError;
 use crate::error::MyError;
 use crate::error::Res;
+use crate::parser::object_parser::standard_set_object;
 use crate::parser::parser_context::FootnoteReferenceDefinition;
 use crate::parser::parser_with_context::parser_with_context;
+use crate::parser::util::exit_matcher_parser;
 use crate::parser::util::get_consumed;
 use crate::parser::util::not_yet_implemented;
 use crate::parser::FootnoteReference;
@@ -28,9 +32,29 @@ pub fn anonymous_footnote<'r, 's>(
     input: &'s str,
 ) -> Res<&'s str, FootnoteReference<'s>> {
     let (remaining, _) = tag_no_case("[fn::")(input)?;
+    let parser_context = context.with_additional_node(ContextElement::FootnoteReferenceDefinition(
+        FootnoteReferenceDefinition {
+            position: remaining,
+            depth: 0,
+        },
+    ));
+    let (remaining, (children, _exit_contents)) = verify(
+        many_till(
+            parser_with_context!(standard_set_object)(&parser_context),
+            parser_with_context!(exit_matcher_parser)(&parser_context),
+        ),
+        |(children, exit_contents)| !children.is_empty() && exit_contents == &"]",
+    )(remaining)?;
 
-    not_yet_implemented()?;
-    todo!()
+    let source = get_consumed(input, remaining);
+    Ok((
+        remaining,
+        FootnoteReference {
+            source,
+            label: None,
+            definition: children,
+        },
+    ))
 }
 
 #[tracing::instrument(ret, level = "debug")]
@@ -43,24 +67,29 @@ fn footnote_definition_end<'r, 's>(
     context: Context<'r, 's>,
     input: &'s str,
 ) -> Res<&'s str, &'s str> {
-    let context_depth = get_bracket_depth(context).expect("This function should only be called from inside a footnote definition.");
+    let context_depth = get_bracket_depth(context)
+        .expect("This function should only be called from inside a footnote definition.");
     let text_since_context_entry = get_consumed(context_depth.position, input);
     let mut current_depth = context_depth.depth;
     for c in text_since_context_entry.chars() {
         match c {
-            '[' => {current_depth += 1;},
+            '[' => {
+                current_depth += 1;
+            }
             ']' if current_depth == 0 => {
                 panic!("Exceeded footnote reference definition bracket depth.")
-            },
+            }
             ']' if current_depth > 0 => {
                 current_depth -= 1;
-            },
+            }
             _ => {}
         }
     }
     if current_depth > 0 {
         // Its impossible for the next character to end the footnote reference definition if we're any amount of brackets deep
-        return Err(nom::Err::Error(CustomError::MyError(MyError("NoFootnoteReferenceDefinitionEnd"))));
+        return Err(nom::Err::Error(CustomError::MyError(MyError(
+            "NoFootnoteReferenceDefinitionEnd",
+        ))));
     }
     tag("]")(input)
 }
diff --git a/src/parser/object.rs b/src/parser/object.rs
index 481408f..42e4401 100644
--- a/src/parser/object.rs
+++ b/src/parser/object.rs
@@ -121,7 +121,7 @@ pub struct ExportSnippet<'s> {
 #[derive(Debug, PartialEq)]
 pub struct FootnoteReference<'s> {
     pub source: &'s str,
-    pub label: &'s str,
+    pub label: Option<&'s str>,
     pub definition: Vec<Object<'s>>,
 }