From a267f23e0f6d89140d10ac710ec48a661b5998c7 Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Wed, 19 Apr 2023 16:51:00 -0400
Subject: [PATCH] Initial code structure for property drawers.

---
 src/compare/diff.rs           | 33 ++++++++++++++++++++++++++++++++-
 src/parser/element.rs         |  9 +++++++++
 src/parser/greater_element.rs |  7 +++++++
 src/parser/mod.rs             |  2 ++
 src/parser/property_drawer.rs | 11 +++++++++++
 5 files changed, 61 insertions(+), 1 deletion(-)
 create mode 100644 src/parser/property_drawer.rs

diff --git a/src/compare/diff.rs b/src/compare/diff.rs
index a1480aae..4920fb3e 100644
--- a/src/compare/diff.rs
+++ b/src/compare/diff.rs
@@ -1,7 +1,6 @@
 use super::sexp::Token;
 use super::util::assert_bounds;
 use super::util::assert_name;
-use crate::compare::util::get_offsets;
 use crate::parser::Comment;
 use crate::parser::Document;
 use crate::parser::DocumentElement;
@@ -13,6 +12,7 @@ use crate::parser::Heading;
 use crate::parser::Paragraph;
 use crate::parser::PlainList;
 use crate::parser::PlainListItem;
+use crate::parser::PropertyDrawer;
 use crate::parser::Section;
 use crate::DynamicBlock;
 
@@ -197,6 +197,7 @@ fn compare_element<'s>(
         Element::FootnoteDefinition(obj) => compare_footnote_definition(source, emacs, obj),
         Element::Comment(obj) => compare_comment(source, emacs, obj),
         Element::Drawer(obj) => compare_drawer(source, emacs, obj),
+        Element::PropertyDrawer(obj) => compare_property_drawer(source, emacs, obj),
     }
 }
 
@@ -428,3 +429,33 @@ fn compare_drawer<'s>(
         children: child_status,
     })
 }
+
+fn compare_property_drawer<'s>(
+    source: &'s str,
+    emacs: &'s Token<'s>,
+    rust: &'s PropertyDrawer<'s>,
+) -> Result<DiffResult, Box<dyn std::error::Error>> {
+    let children = emacs.as_list()?;
+    let mut child_status = Vec::new();
+    let mut this_status = DiffStatus::Good;
+    let emacs_name = "property-drawer";
+    if assert_name(emacs, emacs_name).is_err() {
+        this_status = DiffStatus::Bad;
+    }
+
+    if assert_bounds(source, emacs, rust).is_err() {
+        this_status = DiffStatus::Bad;
+    }
+
+    for (emacs_child, rust_child) in children.iter().skip(2).zip(rust.children.iter()) {
+        // TODO: What are node properties and are they the only legal child of property drawers?
+        // child_status.push(compare_element(source, emacs_child, rust_child)?);
+    }
+
+    Ok(DiffResult {
+        status: this_status,
+        name: emacs_name.to_owned(),
+        message: None,
+        children: child_status,
+    })
+}
diff --git a/src/parser/element.rs b/src/parser/element.rs
index ecf9a80d..e3a2c4e5 100644
--- a/src/parser/element.rs
+++ b/src/parser/element.rs
@@ -8,6 +8,7 @@ use super::greater_element::DynamicBlock;
 use super::greater_element::FootnoteDefinition;
 use super::greater_element::GreaterBlock;
 use super::greater_element::PlainList;
+use super::greater_element::PropertyDrawer;
 use super::lesser_element::Comment;
 use super::lesser_element::Paragraph;
 use super::paragraph::paragraph;
@@ -29,6 +30,7 @@ pub enum Element<'s> {
     FootnoteDefinition(FootnoteDefinition<'s>),
     Comment(Comment<'s>),
     Drawer(Drawer<'s>),
+    PropertyDrawer(PropertyDrawer<'s>),
 }
 
 impl<'s> Source<'s> for Element<'s> {
@@ -41,6 +43,7 @@ impl<'s> Source<'s> for Element<'s> {
             Element::FootnoteDefinition(obj) => obj.source,
             Element::Comment(obj) => obj.source,
             Element::Drawer(obj) => obj.source,
+            Element::PropertyDrawer(obj) => obj.source,
         }
     }
 }
@@ -93,6 +96,12 @@ impl<'s> Source<'s> for Drawer<'s> {
     }
 }
 
+impl<'s> Source<'s> for PropertyDrawer<'s> {
+    fn get_source(&'s self) -> &'s str {
+        self.source
+    }
+}
+
 #[tracing::instrument(ret, level = "debug")]
 pub fn element<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, Element<'s>> {
     let non_paragraph_matcher = parser_with_context!(non_paragraph_element)(context);
diff --git a/src/parser/greater_element.rs b/src/parser/greater_element.rs
index 90187263..c40d85c3 100644
--- a/src/parser/greater_element.rs
+++ b/src/parser/greater_element.rs
@@ -43,3 +43,10 @@ pub struct Drawer<'s> {
     pub name: &'s str,
     pub children: Vec<Element<'s>>,
 }
+
+#[derive(Debug)]
+pub struct PropertyDrawer<'s> {
+    pub source: &'s str,
+    pub name: &'s str,
+    pub children: Vec<Element<'s>>,
+}
diff --git a/src/parser/mod.rs b/src/parser/mod.rs
index 3a2eb612..6359a5c6 100644
--- a/src/parser/mod.rs
+++ b/src/parser/mod.rs
@@ -16,6 +16,7 @@ mod parser_context;
 mod parser_with_context;
 mod plain_list;
 mod plain_text;
+mod property_drawer;
 mod source;
 mod util;
 pub use document::document;
@@ -30,6 +31,7 @@ pub use greater_element::FootnoteDefinition;
 pub use greater_element::GreaterBlock;
 pub use greater_element::PlainList;
 pub use greater_element::PlainListItem;
+pub use greater_element::PropertyDrawer;
 pub use lesser_element::Comment;
 pub use lesser_element::Paragraph;
 pub use source::Source;
diff --git a/src/parser/property_drawer.rs b/src/parser/property_drawer.rs
new file mode 100644
index 00000000..31f2ee53
--- /dev/null
+++ b/src/parser/property_drawer.rs
@@ -0,0 +1,11 @@
+use super::Context;
+use crate::parser::error::Res;
+use crate::parser::greater_element::PropertyDrawer;
+
+#[tracing::instrument(ret, level = "debug")]
+pub fn property_drawer<'r, 's>(
+    context: Context<'r, 's>,
+    input: &'s str,
+) -> Res<&'s str, PropertyDrawer<'s>> {
+    todo!()
+}