From 32897270a5c3b94b22aff4405649f866071a7d89 Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Fri, 17 Mar 2023 16:37:47 -0400
Subject: [PATCH] Support leading whitespace for list items.

---
 src/main.rs              |  8 ++++++--
 src/parser/mod.rs        |  2 ++
 src/parser/paragraph.rs  |  2 +-
 src/parser/plain_list.rs | 22 ++++++++++++++++------
 src/parser/token.rs      |  1 +
 5 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index a50a86c..70abb81 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,4 +1,6 @@
 use crate::parser::document;
+use crate::parser::item;
+use crate::parser::ContextTree;
 use tracing::Level;
 use tracing_subscriber::fmt::format::FmtSpan;
 
@@ -18,8 +20,10 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         .with_span_events(FmtSpan::ENTER | FmtSpan::EXIT)
         .finish();
     tracing::subscriber::set_global_default(subscriber)?;
-    let parsed = document(TEST_DOC);
-    println!("{}\n\n\n", TEST_DOC);
+    // let parsed = document(TEST_DOC);
+    // println!("{}\n\n\n", TEST_DOC);
+    let initial_context: ContextTree<'_, '_> = ContextTree::new();
+    let parsed = item(&initial_context, " 1. foo\n");
     println!("{:#?}", parsed);
     Ok(())
 }
diff --git a/src/parser/mod.rs b/src/parser/mod.rs
index 2f5130b..545ef9f 100644
--- a/src/parser/mod.rs
+++ b/src/parser/mod.rs
@@ -13,3 +13,5 @@ mod token;
 mod util;
 pub use document::document;
 type Context<'r, 's> = &'r parser_context::ContextTree<'r, 's>;
+pub use parser_context::ContextTree;
+pub use plain_list::item;
diff --git a/src/parser/paragraph.rs b/src/parser/paragraph.rs
index 6097ec8..549c2d4 100644
--- a/src/parser/paragraph.rs
+++ b/src/parser/paragraph.rs
@@ -56,7 +56,7 @@ fn context_paragraph_end<'r, 's>(
     paragraph_end(input)
 }
 
-fn paragraph_end(input: &str) -> Res<&str, &str> {
+pub fn paragraph_end(input: &str) -> Res<&str, &str> {
     alt((
         recognize(tuple((
             map(line_break, TextElement::LineBreak),
diff --git a/src/parser/plain_list.rs b/src/parser/plain_list.rs
index 4bb435c..59370a8 100644
--- a/src/parser/plain_list.rs
+++ b/src/parser/plain_list.rs
@@ -4,15 +4,18 @@ use nom::character::complete::anychar;
 use nom::character::complete::digit1;
 use nom::character::complete::line_ending;
 use nom::character::complete::one_of;
+use nom::character::complete::space0;
 use nom::combinator::consumed;
 use nom::combinator::not;
 use nom::combinator::opt;
 use nom::combinator::recognize;
+use nom::multi::many0_count;
 use nom::multi::many1;
 use nom::sequence::tuple;
 
 use super::combinator::context_many_till;
 use super::error::Res;
+use super::paragraph::paragraph_end;
 use super::text::space;
 use super::text::text_element;
 use super::token::ListItem;
@@ -25,8 +28,10 @@ pub fn plain_list<'r, 's>(context: Context<'r, 's>, i: &'s str) -> Res<&'s str,
     todo!()
 }
 
-fn item<'r, 's>(context: Context<'r, 's>, i: &'s str) -> Res<&'s str, ListItem<'s>> {
-    let (remaining, (source, (bul, count, check, tg, sp, (contents, end)))) = consumed(tuple((
+pub fn item<'r, 's>(context: Context<'r, 's>, i: &'s str) -> Res<&'s str, ListItem<'s>> {
+    let (remaining, leading_whitespace) = space0(i)?;
+    let indent_level = leading_whitespace.len();
+    let (remaining, (bul, countset, check, tg, sp, (contents, end))) = tuple((
         bullet,
         opt(tuple((space, counter_set))),
         opt(tuple((space, check_box))),
@@ -34,7 +39,7 @@ fn item<'r, 's>(context: Context<'r, 's>, i: &'s str) -> Res<&'s str, ListItem<'
         space,
         // TODO: This context should probably be something involving the item
         context_many_till(context, text_element, item_end),
-    )))(i)?;
+    ))(remaining)?;
 
     let elements = contents
         .into_iter()
@@ -44,10 +49,16 @@ fn item<'r, 's>(context: Context<'r, 's>, i: &'s str) -> Res<&'s str, ListItem<'
         })
         .collect();
 
+    let source = {
+        let offset = remaining.as_ptr() as usize - i.as_ptr() as usize;
+        &i[..offset]
+    };
+
     let ret = ListItem {
         source,
+        leading_whitespace,
         bullet: bul,
-        counter_set: count.map(|(_spc, count)| count),
+        counter_set: countset.map(|(_spc, count)| count),
         check_box: check.map(|(_spc, check)| check),
         item_tag: tg.map(|(_spc, tg)| tg),
         contents: elements,
@@ -94,6 +105,5 @@ fn tag_separator<'s>(i: &'s str) -> Res<&'s str, &'s str> {
 }
 
 pub fn item_end<'r, 's>(context: Context<'r, 's>, i: &'s str) -> Res<&'s str, &'s str> {
-    // todo
-    todo!()
+    paragraph_end(i)
 }
diff --git a/src/parser/token.rs b/src/parser/token.rs
index 3935377..a7eb0b4 100644
--- a/src/parser/token.rs
+++ b/src/parser/token.rs
@@ -110,6 +110,7 @@ impl<'a> Source<'a> for PlainList<'a> {
 #[derive(Debug)]
 pub struct ListItem<'a> {
     pub source: &'a str,
+    pub leading_whitespace: &'a str,
     pub bullet: &'a str,
     pub counter_set: Option<&'a str>,
     pub check_box: Option<&'a str>,