Experimental custom styles

Cargo.lock

@@ -741,6 +741,7 @@ dependencies = [
  "lsp-server",
  "lsp-types 0.97.0",
  "mlua",
+ "rand 0.8.5",
  "regex",
  "rusqlite",
  "rust-crypto",

Cargo.toml

@@ -37,3 +37,6 @@ tokio = { version = "1.38.1", features = ["macros", "rt-multi-thread", "io-std"]
 tower-lsp = "0.20.0"
 unicode-segmentation = "1.11.0"
 walkdir = "2.5.0"
+
+[dev-dependencies]
+rand = "0.8.5"

src/document/customstyle.rs

@@ -0,0 +1,57 @@
+use std::cell::Ref;
+use std::cell::RefMut;
+use std::collections::HashMap;
+use std::ops::Range;
+use std::rc::Rc;
+
+use ariadne::Report;
+
+use crate::parser::parser::Parser;
+use crate::parser::source::Source;
+use crate::parser::source::Token;
+
+use super::document::Document;
+
+#[derive(Debug, PartialEq, Eq)]
+pub enum CustomStyleToken {
+	Toggle(String),
+	Pair(String, String),
+}
+
+pub trait CustomStyle: core::fmt::Debug {
+	/// Name for the custom style
+	fn name(&self) -> &str;
+	/// Gets the begin and end token for a custom style
+	fn tokens(&self) -> &CustomStyleToken;
+
+	fn on_start<'a>(
+		&self,
+		location: Token,
+		parser: &dyn Parser,
+		document: &'a (dyn Document<'a> + 'a),
+	) -> Result<(), Report<(Rc<dyn Source>, Range<usize>)>>;
+	fn on_end<'a>(
+		&self,
+		location: Token,
+		parser: &dyn Parser,
+		document: &'a (dyn Document<'a> + 'a),
+	) -> Result<(), Report<(Rc<dyn Source>, Range<usize>)>>;
+}
+
+pub trait CustomStyleHolder {
+	/// gets a reference to all defined custom styles
+	fn custom_styles(&self) -> Ref<'_, HashMap<String, Rc<dyn CustomStyle>>>;
+
+	/// gets a (mutable) reference to all defined custom styles
+	fn custom_styles_mut(&self) -> RefMut<'_, HashMap<String, Rc<dyn CustomStyle>>>;
+
+	fn get_custom_style(&self, style_name: &str) -> Option<Rc<dyn CustomStyle>> {
+		self.custom_styles()
+			.get(style_name)
+			.map(|style| style.clone())
+	}
+
+	fn insert_custom_style(&self, style: Rc<dyn CustomStyle>) {
+		self.custom_styles_mut().insert(style.name().into(), style);
+	}
+}

src/document/element.rs

@@ -3,7 +3,6 @@ use std::str::FromStr;
 use crate::compiler::compiler::Compiler;
 use crate::elements::reference::Reference;
 use crate::parser::source::Token;
-use crate::parser::util::PropertyParser;
 use downcast_rs::impl_downcast;
 use downcast_rs::Downcast;
 

src/document/mod.rs

@@ -5,3 +5,4 @@ pub mod element;
 pub mod variable;
 pub mod style;
 pub mod layout;
+pub mod customstyle;

src/document/style.rs

@@ -18,9 +18,6 @@ pub trait ElementStyle: Downcast + core::fmt::Debug {
 	/// Will fail if deserialization fails
 	fn from_json(&self, json: &str) -> Result<Rc<dyn ElementStyle>, String>;
 
-	/// Serializes sytle into json string
-	fn to_json(&self) -> String;
-
 	/// Attempts to deserialize lua table into a new style
 	fn from_lua(
 		&self,
@@ -32,24 +29,24 @@ impl_downcast!(ElementStyle);
 
 pub trait StyleHolder {
 	/// gets a reference to all defined styles
-	fn styles(&self) -> Ref<'_, HashMap<String, Rc<dyn ElementStyle>>>;
+	fn element_styles(&self) -> Ref<'_, HashMap<String, Rc<dyn ElementStyle>>>;
 
 	/// gets a (mutable) reference to all defined styles
-	fn styles_mut(&self) -> RefMut<'_, HashMap<String, Rc<dyn ElementStyle>>>;
+	fn element_styles_mut(&self) -> RefMut<'_, HashMap<String, Rc<dyn ElementStyle>>>;
 
 	/// Checks if a given style key is registered
-	fn is_style_registered(&self, style_key: &str) -> bool { self.styles().contains_key(style_key) }
+	fn is_style_registered(&self, style_key: &str) -> bool { self.element_styles().contains_key(style_key) }
 
 	/// Gets the current active style for an element
 	/// NOTE: Will panic if a style is not defined for a given element
 	/// If you need to process user input, use [`is_registered`]
 	fn current_style(&self, style_key: &str) -> Rc<dyn ElementStyle> {
-		self.styles().get(style_key).map(|rc| rc.clone()).unwrap()
+		self.element_styles().get(style_key).map(|rc| rc.clone()).unwrap()
 	}
 
 	/// Sets the [`style`]
 	fn set_current_style(&self, style: Rc<dyn ElementStyle>) {
-		self.styles_mut().insert(style.key().to_string(), style);
+		self.element_styles_mut().insert(style.key().to_string(), style);
 	}
 }
 
@@ -65,8 +62,6 @@ macro_rules! impl_elementstyle {
 					.map(|obj| std::rc::Rc::new(obj) as std::rc::Rc<dyn ElementStyle>)
 			}
 
-			fn to_json(&self) -> String { serde_json::to_string(self).unwrap() }
-
 			fn from_lua(
 				&self,
 				lua: &mlua::Lua,

src/elements/customstyle.rs

@@ -0,0 +1,557 @@
+use std::any::Any;
+use std::cell::RefCell;
+use std::collections::HashMap;
+use std::ops::Range;
+use std::rc::Rc;
+use std::sync::Arc;
+
+use ariadne::Fmt;
+use ariadne::Label;
+use ariadne::Report;
+use ariadne::ReportKind;
+use mlua::Error::BadArgument;
+use mlua::Function;
+use mlua::Lua;
+
+use crate::document::customstyle::CustomStyle;
+use crate::document::customstyle::CustomStyleToken;
+use crate::document::document::Document;
+use crate::document::document::DocumentAccessors;
+use crate::lua::kernel::function_with_context;
+use crate::lua::kernel::KernelContext;
+use crate::lua::kernel::CTX;
+use crate::parser::parser::Parser;
+use crate::parser::rule::Rule;
+use crate::parser::source::Cursor;
+use crate::parser::source::Source;
+use crate::parser::source::Token;
+use crate::parser::state::Scope;
+use crate::parser::state::State;
+
+use lazy_static::lazy_static;
+
+use super::paragraph::Paragraph;
+
+#[derive(Debug)]
+struct LuaCustomStyle {
+	pub(self) name: String,
+	pub(self) tokens: CustomStyleToken,
+	pub(self) start: String,
+	pub(self) end: String,
+}
+
+impl CustomStyle for LuaCustomStyle {
+	fn name(&self) -> &str { self.name.as_str() }
+
+	fn tokens(&self) -> &CustomStyleToken { &self.tokens }
+
+	fn on_start<'a>(
+		&self,
+		location: Token,
+		parser: &dyn Parser,
+		document: &'a dyn Document<'a>,
+	) -> Result<(), Report<(Rc<dyn Source>, Range<usize>)>> {
+		let kernel = parser.get_kernel("main").unwrap();
+		let ctx = KernelContext {
+			location: location.clone(),
+			parser,
+			document,
+		};
+
+		let mut result = Ok(());
+		kernel.run_with_context(ctx, |lua| {
+			let chunk = lua.load(self.start.as_str());
+			if let Err(err) = chunk.eval::<()>() {
+				result = Err(
+					Report::build(ReportKind::Error, location.source(), location.start())
+						.with_message("Lua execution failed")
+						.with_label(
+							Label::new((location.source(), location.range.clone()))
+								.with_message(err.to_string())
+								.with_color(parser.colors().error),
+						)
+						.with_note(format!(
+							"When trying to start custom style {}",
+							self.name().fg(parser.colors().info)
+						))
+						.finish(),
+				);
+			}
+		});
+
+		result
+	}
+
+	fn on_end<'a>(
+		&self,
+		location: Token,
+		parser: &dyn Parser,
+		document: &'a dyn Document<'a>,
+	) -> Result<(), Report<(Rc<dyn Source>, Range<usize>)>> {
+		let kernel = parser.get_kernel("main").unwrap();
+		let ctx = KernelContext {
+			location: location.clone(),
+			parser,
+			document,
+		};
+
+		let mut result = Ok(());
+		kernel.run_with_context(ctx, |lua| {
+			let chunk = lua.load(self.end.as_str());
+			if let Err(err) = chunk.eval::<()>() {
+				result = Err(
+					Report::build(ReportKind::Error, location.source(), location.start())
+						.with_message("Lua execution failed")
+						.with_label(
+							Label::new((location.source(), location.range.clone()))
+								.with_message(err.to_string())
+								.with_color(parser.colors().error),
+						)
+						.with_note(format!(
+							"When trying to end custom style {}",
+							self.name().fg(parser.colors().info)
+						))
+						.finish(),
+				);
+			}
+		});
+
+		result
+	}
+}
+
+struct CustomStyleState {
+	toggled: HashMap<String, Token>,
+}
+
+impl State for CustomStyleState {
+	fn scope(&self) -> Scope { Scope::PARAGRAPH }
+
+	fn on_remove<'a>(
+		&self,
+		parser: &dyn Parser,
+		document: &dyn Document,
+	) -> Vec<Report<'a, (Rc<dyn Source>, Range<usize>)>> {
+		let mut reports = vec![];
+
+		self.toggled.iter().for_each(|(style, token)| {
+			let paragraph = document.last_element::<Paragraph>().unwrap();
+			let paragraph_end = paragraph
+				.content
+				.last()
+				.and_then(|last| {
+					Some((
+						last.location().source(),
+						last.location().end() - 1..last.location().end(),
+					))
+				})
+				.unwrap();
+
+			reports.push(
+				Report::build(ReportKind::Error, token.source(), token.start())
+					.with_message("Unterminated Custom Style")
+					.with_label(
+						Label::new((token.source(), token.range.clone()))
+							.with_order(1)
+							.with_message(format!(
+								"Style {} starts here",
+								style.fg(parser.colors().info)
+							))
+							.with_color(parser.colors().error),
+					)
+					.with_label(
+						Label::new(paragraph_end)
+							.with_order(1)
+							.with_message(format!("Paragraph ends here"))
+							.with_color(parser.colors().error),
+					)
+					.with_note("Styles cannot span multiple documents (i.e @import)")
+					.finish(),
+			);
+		});
+
+		return reports;
+	}
+}
+
+pub struct CustomStyleRule;
+
+lazy_static! {
+	static ref STATE_NAME: String = "elements.custom_style".to_string();
+}
+
+impl Rule for CustomStyleRule {
+	fn name(&self) -> &'static str { "Custom Style" }
+
+	fn next_match(&self, parser: &dyn Parser, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> {
+		let content = cursor.source.content();
+
+		let mut closest_match = usize::MAX;
+		let mut matched_style = (None, false);
+		parser
+			.custom_styles()
+			.iter()
+			.for_each(|(_name, style)| match style.tokens() {
+				CustomStyleToken::Toggle(s) => {
+					if let Some(pos) = &content[cursor.pos..].find(s) {
+						if *pos < closest_match {
+							closest_match = *pos;
+							matched_style = (Some(style.clone()), false);
+						}
+					}
+				}
+				CustomStyleToken::Pair(begin, end) => {
+					if let Some(pos) = &content[cursor.pos..].find(begin) {
+						if *pos < closest_match {
+							closest_match = *pos;
+							matched_style = (Some(style.clone()), false);
+						}
+					}
+
+					if let Some(pos) = &content[cursor.pos..].find(end) {
+						if *pos < closest_match {
+							closest_match = *pos;
+							matched_style = (Some(style.clone()), true);
+						}
+					}
+				}
+			});
+
+		if closest_match == usize::MAX {
+			None
+		} else {
+			Some((
+				closest_match + cursor.pos,
+				Box::new((matched_style.0.unwrap().clone(), matched_style.1)) as Box<dyn Any>,
+			))
+		}
+	}
+
+	fn on_match<'a>(
+		&self,
+		parser: &dyn Parser,
+		document: &'a dyn Document<'a>,
+		cursor: Cursor,
+		match_data: Option<Box<dyn Any>>,
+	) -> (Cursor, Vec<Report<'_, (Rc<dyn Source>, Range<usize>)>>) {
+		let (style, end) = match_data
+			.as_ref()
+			.unwrap()
+			.downcast_ref::<(Rc<dyn CustomStyle>, bool)>()
+			.unwrap();
+
+		let query = parser.state().query(&STATE_NAME);
+		let state = match query {
+			Some(state) => state,
+			None => {
+				// Insert as a new state
+				match parser.state_mut().insert(
+					STATE_NAME.clone(),
+					Rc::new(RefCell::new(CustomStyleState {
+						toggled: HashMap::new(),
+					})),
+				) {
+					Err(_) => panic!("Unknown error"),
+					Ok(state) => state,
+				}
+			}
+		};
+
+		let (close, token) = match style.tokens() {
+			CustomStyleToken::Toggle(s) => {
+				let mut borrow = state.borrow_mut();
+				let state = borrow.downcast_mut::<CustomStyleState>().unwrap();
+
+				match state.toggled.get(style.name()) {
+					Some(_) => {
+						// Terminate style
+						let token =
+							Token::new(cursor.pos..cursor.pos + s.len(), cursor.source.clone());
+
+						state.toggled.remove(style.name());
+						(true, token)
+					}
+					None => {
+						// Start style
+						let token =
+							Token::new(cursor.pos..cursor.pos + s.len(), cursor.source.clone());
+
+						state.toggled.insert(style.name().into(), token.clone());
+						(false, token)
+					}
+				}
+			}
+			CustomStyleToken::Pair(s_begin, s_end) => {
+				let mut borrow = state.borrow_mut();
+				let state = borrow.downcast_mut::<CustomStyleState>().unwrap();
+
+				if *end {
+					// Terminate style
+					let token =
+						Token::new(cursor.pos..cursor.pos + s_end.len(), cursor.source.clone());
+					if state.toggled.get(style.name()).is_none() {
+						return (
+							cursor.at(cursor.pos + s_end.len()),
+							vec![
+								Report::build(ReportKind::Error, token.source(), token.start())
+									.with_message("Invalid End of Style")
+									.with_label(
+										Label::new((token.source(), token.range.clone()))
+											.with_order(1)
+											.with_message(format!(
+											"Cannot end style {} here, is it not started anywhere",
+											style.name().fg(parser.colors().info)
+										))
+											.with_color(parser.colors().error),
+									)
+									.finish(),
+							],
+						);
+					}
+
+					state.toggled.remove(style.name());
+					(true, token)
+				} else {
+					// Start style
+					let token = Token::new(
+						cursor.pos..cursor.pos + s_begin.len(),
+						cursor.source.clone(),
+					);
+					if let Some(start_token) = state.toggled.get(style.name()) {
+						return (
+							cursor.at(cursor.pos + s_end.len()),
+							vec![Report::build(
+								ReportKind::Error,
+								start_token.source(),
+								start_token.start(),
+							)
+							.with_message("Invalid Start of Style")
+							.with_label(
+								Label::new((token.source(), token.range.clone()))
+									.with_order(1)
+									.with_message(format!(
+										"Style cannot {} starts here",
+										style.name().fg(parser.colors().info)
+									))
+									.with_color(parser.colors().error),
+							)
+							.with_label(
+								Label::new((start_token.source(), start_token.range.clone()))
+									.with_order(2)
+									.with_message(format!(
+										"Style {} starts previously here",
+										style.name().fg(parser.colors().info)
+									))
+									.with_color(parser.colors().error),
+							)
+							.finish()],
+						);
+					}
+
+					state.toggled.insert(style.name().into(), token.clone());
+					(false, token)
+				}
+			}
+		};
+
+		if let Err(rep) = if close {
+			style.on_end(token.clone(), parser, document)
+		} else {
+			style.on_start(token.clone(), parser, document)
+		} {
+			return (
+				cursor.at(token.end()),
+				vec![unsafe {
+					// TODO
+					std::mem::transmute(rep)
+				}],
+			);
+		} else {
+			(cursor.at(token.end()), vec![])
+		}
+	}
+
+	fn lua_bindings<'lua>(&self, lua: &'lua Lua) -> Option<Vec<(String, Function<'lua>)>> {
+		let mut bindings = vec![];
+
+		bindings.push((
+			"define_toggled".into(),
+			lua.create_function(
+				|_, (name, token, on_start, on_end): (String, String, String, String)| {
+					let mut result = Ok(());
+
+					let style = LuaCustomStyle {
+						tokens: CustomStyleToken::Toggle(token),
+						name: name.clone(),
+						start: on_start,
+						end: on_end,
+					};
+
+					CTX.with_borrow(|ctx| {
+						ctx.as_ref().map(|ctx| {
+							if let Some(_) = ctx.parser.get_custom_style(name.as_str()) {
+								result = Err(BadArgument {
+									to: Some("define_toggled".to_string()),
+									pos: 1,
+									name: Some("name".to_string()),
+									cause: Arc::new(mlua::Error::external(format!(
+										"Custom style with name `{name}` already exists"
+									))),
+								});
+								return;
+							}
+							ctx.parser.insert_custom_style(Rc::new(style));
+						});
+					});
+
+					result
+				},
+			)
+			.unwrap(),
+		));
+
+		bindings.push((
+			"define_paired".into(),
+			lua.create_function(
+				|_,
+				 (name, token_start, token_end, on_start, on_end): (
+					String,
+					String,
+					String,
+					String,
+					String,
+				)| {
+					let mut result = Ok(());
+
+					let style = LuaCustomStyle {
+						tokens: CustomStyleToken::Pair(token_start, token_end),
+						name: name.clone(),
+						start: on_start,
+						end: on_end,
+					};
+
+					CTX.with_borrow(|ctx| {
+						ctx.as_ref().map(|ctx| {
+							if let Some(_) = ctx.parser.get_custom_style(name.as_str()) {
+								result = Err(BadArgument {
+									to: Some("define_toggled".to_string()),
+									pos: 1,
+									name: Some("name".to_string()),
+									cause: Arc::new(mlua::Error::external(format!(
+										"Custom style with name `{name}` already exists"
+									))),
+								});
+								return;
+							}
+							ctx.parser.insert_custom_style(Rc::new(style));
+						});
+					});
+
+					result
+				},
+			)
+			.unwrap(),
+		));
+
+		Some(bindings)
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use crate::elements::raw::Raw;
+	use crate::elements::text::Text;
+	use crate::parser::langparser::LangParser;
+	use crate::parser::source::SourceFile;
+	use crate::validate_document;
+
+	use super::*;
+
+	#[test]
+	fn toggle() {
+		let source = Rc::new(SourceFile::with_content(
+			"".to_string(),
+			r#"
+%<[main]
+function my_style_start()
+	nml.raw.push("inline", "start")
+end
+function my_style_end()
+	nml.raw.push("inline", "end")
+end
+function red_style_start()
+	nml.raw.push("inline", "<a style=\"color:red\">")
+end
+function red_style_end()
+	nml.raw.push("inline", "</a>")
+end
+nml.custom_style.define_toggled("My Style", "|", "my_style_start()", "my_style_end()")
+nml.custom_style.define_toggled("My Style2", "°", "red_style_start()", "red_style_end()")
+>%
+pre |styled| post °Hello°.
+"#
+			.to_string(),
+			None,
+		));
+		let parser = LangParser::default();
+		let doc = parser.parse(source, None);
+
+		validate_document!(doc.content().borrow(), 0,
+			Paragraph {
+				Text { content == "pre " };
+				Raw { content == "start" };
+				Text { content == "styled" };
+				Raw { content == "end" };
+				Text { content == " post " };
+				Raw { content == "<a style=\"color:red\">" };
+				Text { content == "Hello" };
+				Raw { content == "</a>" };
+				Text { content == "." };
+			};
+		);
+	}
+
+	#[test]
+	fn paired() {
+		let source = Rc::new(SourceFile::with_content(
+			"".to_string(),
+			r#"
+%<[main]
+function my_style_start()
+	nml.raw.push("inline", "start")
+end
+function my_style_end()
+	nml.raw.push("inline", "end")
+end
+function red_style_start()
+	nml.raw.push("inline", "<a style=\"color:red\">")
+end
+function red_style_end()
+	nml.raw.push("inline", "</a>")
+end
+nml.custom_style.define_paired("My Style", "[", "]", "my_style_start()", "my_style_end()")
+nml.custom_style.define_paired("My Style2", "(", ")", "red_style_start()", "red_style_end()")
+>%
+pre [styled] post (Hello).
+"#
+			.to_string(),
+			None,
+		));
+		let parser = LangParser::default();
+		let doc = parser.parse(source, None);
+
+		validate_document!(doc.content().borrow(), 0,
+			Paragraph {
+				Text { content == "pre " };
+				Raw { content == "start" };
+				Text { content == "styled" };
+				Raw { content == "end" };
+				Text { content == " post " };
+				Raw { content == "<a style=\"color:red\">" };
+				Text { content == "Hello" };
+				Raw { content == "</a>" };
+				Text { content == "." };
+			};
+		);
+	}
+}

src/elements/elemstyle.rs

@@ -10,23 +10,15 @@ use ariadne::ReportKind;
 use mlua::Error::BadArgument;
 use mlua::Function;
 use mlua::Lua;
-use mlua::LuaSerdeExt;
-use mlua::Table;
 use mlua::Value;
-use regex::Captures;
 use regex::Regex;
 
 use crate::document::document::Document;
-use crate::document::{self};
 use crate::lua::kernel::CTX;
 use crate::parser::parser::Parser;
-use crate::parser::rule::RegexRule;
 use crate::parser::rule::Rule;
 use crate::parser::source::Cursor;
 use crate::parser::source::Source;
-use crate::parser::source::Token;
-
-use super::variable::VariableRule;
 
 pub struct ElemStyleRule {
 	start_re: Regex,
@@ -66,7 +58,7 @@ impl ElemStyleRule {
 impl Rule for ElemStyleRule {
 	fn name(&self) -> &'static str { "Element Style" }
 
-	fn next_match(&self, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> {
+	fn next_match(&self, _parser: &dyn Parser, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> {
 		self.start_re
 			.find_at(cursor.source.content(), cursor.pos)
 			.map_or(None, |m| {

src/elements/list.rs

@@ -252,7 +252,7 @@ impl ListRule {
 impl Rule for ListRule {
 	fn name(&self) -> &'static str { "List" }
 
-	fn next_match(&self, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> {
+	fn next_match(&self, _parser: &dyn Parser, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> {
 		self.start_re
 			.find_at(cursor.source.content(), cursor.pos)
 			.map_or(None, |m| {
@@ -440,7 +440,6 @@ impl Rule for ListRule {
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use crate::compiler::compiler::Target;
 	use crate::elements::paragraph::Paragraph;
 	use crate::elements::text::Text;
 	use crate::parser::langparser::LangParser;

src/elements/mod.rs

@@ -17,3 +17,4 @@ pub mod tex;
 pub mod text;
 pub mod variable;
 pub mod elemstyle;
+pub mod customstyle;

src/elements/paragraph.rs

@@ -108,7 +108,7 @@ impl ParagraphRule {
 impl Rule for ParagraphRule {
 	fn name(&self) -> &'static str { "Paragraphing" }
 
-	fn next_match(&self, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> {
+	fn next_match(&self, _parser: &dyn Parser, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> {
 		self.re
 			.find_at(cursor.source.content(), cursor.pos)
 			.and_then(|m| Some((m.start(), Box::new([false; 0]) as Box<dyn Any>)))

src/elements/raw.rs

@@ -27,10 +27,10 @@ use std::str::FromStr;
 use std::sync::Arc;
 
 #[derive(Debug)]
-struct Raw {
+pub struct Raw {
-	pub(self) location: Token,
+	pub location: Token,
-	pub(self) kind: ElemKind,
+	pub kind: ElemKind,
-	pub(self) content: String,
+	pub content: String,
 }
 
 impl Element for Raw {
@@ -265,7 +265,6 @@ impl RegexRule for RawRule {
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use crate::compiler::compiler::Target;
 	use crate::elements::paragraph::Paragraph;
 	use crate::elements::text::Text;
 	use crate::parser::langparser::LangParser;

src/elements/registrar.rs

@@ -1,4 +1,5 @@
 use crate::parser::parser::Parser;
+use crate::parser::parser::ParserStrategy;
 
 use super::code::CodeRule;
 use super::comment::CommentRule;
@@ -14,6 +15,7 @@ use super::raw::RawRule;
 use super::script::ScriptRule;
 use super::section::SectionRule;
 use super::style::StyleRule;
+use super::customstyle::CustomStyleRule;
 use super::tex::TexRule;
 use super::text::TextRule;
 use super::variable::VariableRule;
@@ -37,6 +39,7 @@ pub fn register<P: Parser>(parser: &mut P) {
 	parser.add_rule(Box::new(LayoutRule::new()), None).unwrap();
 
 	parser.add_rule(Box::new(StyleRule::new()), None).unwrap();
+	parser.add_rule(Box::new(CustomStyleRule{}), None).unwrap();
 	parser.add_rule(Box::new(SectionRule::new()), None).unwrap();
 	parser.add_rule(Box::new(LinkRule::new()), None).unwrap();
 	parser.add_rule(Box::new(TextRule::default()), None).unwrap();

src/elements/style.rs

@@ -96,10 +96,6 @@ impl State for StyleState {
 				} // Style not enabled
 				let token = token.as_ref().unwrap();
 
-				//let range = range.as_ref().unwrap();
-
-				//let active_range = range.start .. paragraph.location().end()-1;
-
 				let paragraph = document.last_element::<Paragraph>().unwrap();
 				let paragraph_end = paragraph
 					.content
@@ -112,16 +108,9 @@ impl State for StyleState {
 					})
 					.unwrap();
 
-				// TODO: Allow style to span multiple documents if they don't break paragraph.
 				reports.push(
 					Report::build(ReportKind::Error, token.source(), token.start())
-						.with_message("Unterminated style")
+						.with_message("Unterminated Style")
-						//.with_label(
-						//	Label::new((document.source(), active_range.clone()))
-						//	.with_order(0)
-						//	.with_message(format!("Style {} is not terminated before the end of paragraph",
-						//	name.fg(parser.colors().info)))
-						//	.with_color(parser.colors().error))
 						.with_label(
 							Label::new((token.source(), token.range.clone()))
 								.with_order(1)
@@ -129,13 +118,13 @@ impl State for StyleState {
 									"Style {} starts here",
 									name.fg(parser.colors().info)
 								))
-								.with_color(parser.colors().info),
+								.with_color(parser.colors().error),
 						)
 						.with_label(
 							Label::new(paragraph_end)
 								.with_order(1)
 								.with_message(format!("Paragraph ends here"))
-								.with_color(parser.colors().info),
+								.with_color(parser.colors().error),
 						)
 						.with_note("Styles cannot span multiple documents (i.e @import)")
 						.finish(),
@@ -199,7 +188,7 @@ impl RegexRule for StyleRule {
 			}
 		};
 
-		if let Some(style_state) = state.borrow_mut().as_any_mut().downcast_mut::<StyleState>() {
+		if let Some(style_state) = state.borrow_mut().downcast_mut::<StyleState>() {
 			style_state.toggled[index] = style_state.toggled[index]
 				.clone()
 				.map_or(Some(token.clone()), |_| None);

src/elements/text.rs

@@ -48,7 +48,7 @@ pub struct TextRule;
 impl Rule for TextRule {
 	fn name(&self) -> &'static str { "Text" }
 
-	fn next_match(&self, _cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> { None }
+	fn next_match(&self, _parser: &dyn Parser, _cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> { None }
 
 	fn on_match(
 		&self,

src/lsp/parser.rs

@@ -1,6 +1,6 @@
-use std::{cell::{RefCell, RefMut}, collections::HashMap, rc::Rc};
+use std::{cell::{Ref, RefCell, RefMut}, collections::HashMap, rc::Rc};
 
-use crate::{document::{document::Document, element::Element, layout::{LayoutHolder, LayoutType}, style::{ElementStyle, StyleHolder}}, lua::kernel::{Kernel, KernelHolder}, parser::{parser::{Parser, ReportColors}, rule::Rule, source::{Cursor, Source}, state::StateHolder}};
+use crate::{document::{customstyle::{CustomStyle, CustomStyleHolder}, document::Document, element::Element, layout::{LayoutHolder, LayoutType}, style::{ElementStyle, StyleHolder}}, lua::kernel::{Kernel, KernelHolder}, parser::{parser::{Parser, ReportColors}, rule::Rule, source::{Cursor, Source}, state::StateHolder}};
 
 #[derive(Debug, Clone)]
 pub struct LineCursor
@@ -112,7 +112,7 @@ impl Parser for LsParser
     fn rules(&self) -> &Vec<Box<dyn Rule>> { &self.rules }
     fn rules_mut(&mut self) -> &mut Vec<Box<dyn Rule>> { &mut self.rules }
 
-	fn state(&self) -> std::cell::Ref<'_, StateHolder> { self.state.borrow() }
+	fn state(&self) -> Ref<'_, StateHolder> { self.state.borrow() }
 	fn state_mut(&self) -> std::cell::RefMut<'_, StateHolder> { self.state.borrow_mut() }
 	
 	fn has_error(&self) -> bool { true }
@@ -148,17 +148,17 @@ impl KernelHolder for LsParser
 }
 
 impl StyleHolder for LsParser {
-    fn styles(&self) -> std::cell::Ref<'_, HashMap<String, Rc<dyn ElementStyle>>> {
+    fn element_styles(&self) -> Ref<'_, HashMap<String, Rc<dyn ElementStyle>>> {
         todo!()
     }
 
-    fn styles_mut(&self) -> RefMut<'_, HashMap<String, Rc<dyn ElementStyle>>> {
+    fn element_styles_mut(&self) -> RefMut<'_, HashMap<String, Rc<dyn ElementStyle>>> {
         todo!()
     }
 }
 
 impl LayoutHolder for LsParser {
-    fn layouts(&self) -> std::cell::Ref<'_, HashMap<String, Rc<dyn LayoutType>>> {
+    fn layouts(&self) -> Ref<'_, HashMap<String, Rc<dyn LayoutType>>> {
         todo!()
     }
 
@@ -166,3 +166,13 @@ impl LayoutHolder for LsParser {
         todo!()
     }
 }
+
+impl CustomStyleHolder for LsParser {
+    fn custom_styles(&self) -> Ref<'_, HashMap<String, Rc<dyn CustomStyle>>> {
+        todo!()
+    }
+
+    fn custom_styles_mut(&self) -> RefMut<'_, HashMap<String, Rc<dyn CustomStyle>>> {
+        todo!()
+    }
+}

src/lua/kernel.rs

@@ -1,6 +1,10 @@
 use std::cell::RefCell;
 use std::cell::RefMut;
 
+use mlua::Error;
+use mlua::FromLuaMulti;
+use mlua::Function;
+use mlua::IntoLuaMulti;
 use mlua::Lua;
 
 use crate::document::document::Document;
@@ -72,3 +76,19 @@ pub trait KernelHolder {
 
 	fn insert_kernel(&self, name: String, kernel: Kernel) -> RefMut<'_, Kernel>;
 }
+
+/// Runs a lua function with a context
+///
+/// This is the only way lua functions shoule be ran, because exported
+/// functions may require the context in order to operate
+pub fn function_with_context<'lua, A, R>(context: KernelContext, fun: &Function<'lua>, args: A) -> Result<R, Error>
+where
+	A: IntoLuaMulti<'lua>,
+	R: FromLuaMulti<'lua>,
+{
+	CTX.set(Some(unsafe { std::mem::transmute(context) }));
+	let ret = fun.call::<A, R>(args);
+	CTX.set(None);
+
+	ret
+}

src/main.rs

@@ -215,7 +215,13 @@ fn main() -> ExitCode {
 			}
 		}
 		match std::fs::metadata(&output) {
-			Ok(_) => {}
+			Ok(output_meta) => {
+				if !output_meta.is_dir()
+				{
+					eprintln!("Input is a directory, but ouput is not a directory, halting");
+					return ExitCode::FAILURE;
+				}
+			}
 			Err(e) => {
 				eprintln!("Unable to get metadata for output `{output}`: {e}");
 				return ExitCode::FAILURE;

src/parser/langparser.rs

@@ -9,6 +9,8 @@ use std::rc::Rc;
 use ariadne::Label;
 use ariadne::Report;
 
+use crate::document::customstyle::CustomStyle;
+use crate::document::customstyle::CustomStyleHolder;
 use crate::document::document::Document;
 use crate::document::document::DocumentAccessors;
 use crate::document::element::ContainerElement;
@@ -29,6 +31,7 @@ use crate::parser::source::SourceFile;
 use crate::parser::source::VirtualSource;
 
 use super::parser::Parser;
+use super::parser::ParserStrategy;
 use super::parser::ReportColors;
 use super::rule::Rule;
 use super::source::Cursor;
@@ -49,6 +52,7 @@ pub struct LangParser {
 	pub kernels: RefCell<HashMap<String, Kernel>>,
 	pub styles: RefCell<HashMap<String, Rc<dyn ElementStyle>>>,
 	pub layouts: RefCell<HashMap<String, Rc<dyn LayoutType>>>,
+	pub custom_styles: RefCell<HashMap<String, Rc<dyn CustomStyle>>>,
 }
 
 impl LangParser {
@@ -61,6 +65,7 @@ impl LangParser {
 			kernels: RefCell::new(HashMap::new()),
 			styles: RefCell::new(HashMap::new()),
 			layouts: RefCell::new(HashMap::new()),
+			custom_styles: RefCell::new(HashMap::new()),
 		};
 		// Register rules
 		register(&mut s);
@@ -316,21 +321,29 @@ impl KernelHolder for LangParser {
 }
 
 impl StyleHolder for LangParser {
-	fn styles(&self) -> Ref<'_, HashMap<String, Rc<dyn ElementStyle>>> { self.styles.borrow() }
+	fn element_styles(&self) -> Ref<'_, HashMap<String, Rc<dyn ElementStyle>>> {
+		self.styles.borrow()
+	}
 
-	fn styles_mut(&self) -> RefMut<'_, HashMap<String, Rc<dyn ElementStyle>>> {
+	fn element_styles_mut(&self) -> RefMut<'_, HashMap<String, Rc<dyn ElementStyle>>> {
 		self.styles.borrow_mut()
 	}
 }
 
 impl LayoutHolder for LangParser {
-	fn layouts(&self) -> Ref<'_, HashMap<String, Rc<dyn crate::document::layout::LayoutType>>> {
+	fn layouts(&self) -> Ref<'_, HashMap<String, Rc<dyn LayoutType>>> { self.layouts.borrow() }
-		self.layouts.borrow()
-	}
 
-	fn layouts_mut(
+	fn layouts_mut(&self) -> RefMut<'_, HashMap<String, Rc<dyn LayoutType>>> {
-		&self,
-	) -> RefMut<'_, HashMap<String, Rc<dyn crate::document::layout::LayoutType>>> {
 		self.layouts.borrow_mut()
 	}
 }
+
+impl CustomStyleHolder for LangParser {
+	fn custom_styles(&self) -> Ref<'_, HashMap<String, Rc<dyn CustomStyle>>> {
+		self.custom_styles.borrow()
+	}
+
+	fn custom_styles_mut(&self) -> RefMut<'_, HashMap<String, Rc<dyn CustomStyle>>> {
+		self.custom_styles.borrow_mut()
+	}
+}

src/parser/parser.rs

@@ -8,6 +8,7 @@ use super::rule::Rule;
 use super::source::Cursor;
 use super::source::Source;
 use super::state::StateHolder;
+use crate::document::customstyle::CustomStyleHolder;
 use crate::document::document::Document;
 use crate::document::element::Element;
 use crate::document::layout::LayoutHolder;
@@ -43,7 +44,7 @@ impl ReportColors {
 	}
 }
 
-pub trait Parser: KernelHolder + StyleHolder + LayoutHolder {
+pub trait Parser: KernelHolder + StyleHolder + LayoutHolder + CustomStyleHolder {
 	/// Gets the colors for formatting errors
 	///
 	/// When colors are disabled, all colors should resolve to empty string
@@ -52,6 +53,36 @@ pub trait Parser: KernelHolder + StyleHolder + LayoutHolder {
 	fn rules(&self) -> &Vec<Box<dyn Rule>>;
 	fn rules_mut(&mut self) -> &mut Vec<Box<dyn Rule>>;
 
+	fn state(&self) -> Ref<'_, StateHolder>;
+	fn state_mut(&self) -> RefMut<'_, StateHolder>;
+
+	fn has_error(&self) -> bool;
+
+	/// Add an [`Element`] to the [`Document`]
+	fn push<'a>(&self, doc: &dyn Document, elem: Box<dyn Element>);
+
+	/// Parse [`Source`] into a new [`Document`]
+	fn parse<'a>(
+		&self,
+		source: Rc<dyn Source>,
+		parent: Option<&'a dyn Document<'a>>,
+	) -> Box<dyn Document<'a> + 'a>;
+
+	/// Parse [`Source`] into an already existing [`Document`]
+	fn parse_into<'a>(&self, source: Rc<dyn Source>, document: &'a dyn Document<'a>);
+}
+
+pub trait ParserStrategy {
+	fn add_rule(&mut self, rule: Box<dyn Rule>, after: Option<&'static str>) -> Result<(), String>;
+
+	fn update_matches(
+		&self,
+		cursor: &Cursor,
+		matches: &mut Vec<(usize, Option<Box<dyn Any>>)>,
+	) -> (Cursor, Option<&Box<dyn Rule>>, Option<Box<dyn Any>>);
+}
+
+impl<T: Parser> ParserStrategy for T {
     fn add_rule(&mut self, rule: Box<dyn Rule>, after: Option<&'static str>) -> Result<(), String> {
 		// Error on duplicate rule
 		let rule_name = (*rule).name();
@@ -91,14 +122,6 @@ pub trait Parser: KernelHolder + StyleHolder + LayoutHolder {
 		Ok(())
     }
 
-	fn state(&self) -> Ref<'_, StateHolder>;
-	fn state_mut(&self) -> RefMut<'_, StateHolder>;
-
-	fn has_error(&self) -> bool;
-
-	// Update [`matches`] and returns the position of the next matched rule.
-	// If rule is empty, it means that there are no rules left to parse (i.e
-	// end of document).
     fn update_matches(
 		    &self,
 		    cursor: &Cursor,
@@ -111,11 +134,12 @@ pub trait Parser: KernelHolder + StyleHolder + LayoutHolder {
 			.zip(matches.iter_mut())
 			.for_each(|(rule, (matched_at, match_data))| {
 				// Don't upate if not stepped over yet
-				if *matched_at > cursor.pos {
+				if *matched_at > cursor.pos && rule.downcast_ref::<crate::elements::customstyle::CustomStyleRule>().is_none() {
+					// TODO: maybe we should expose matches() so it becomes possible to dynamically register a new rule
 					return;
 				}
 
-				(*matched_at, *match_data) = match rule.next_match(cursor) {
+				(*matched_at, *match_data) = match rule.next_match(self, cursor) {
 					None => (usize::MAX, None),
 					Some((mut pos, mut data)) => {
 						// Check if escaped
@@ -136,7 +160,7 @@ pub trait Parser: KernelHolder + StyleHolder + LayoutHolder {
 							}
 
 							// Find next potential match
-							(pos, data) = match rule.next_match(&cursor.at(pos + 1)) {
+							(pos, data) = match rule.next_match(self, &cursor.at(pos + 1)) {
 								Some((new_pos, new_data)) => (new_pos, new_data),
 								None => (usize::MAX, data), // Stop iterating
 							}
@@ -167,17 +191,4 @@ pub trait Parser: KernelHolder + StyleHolder + LayoutHolder {
 			std::mem::replace(&mut matches[winner].1, None),
 		)
     }
-
-	/// Add an [`Element`] to the [`Document`]
-	fn push<'a>(&self, doc: &dyn Document, elem: Box<dyn Element>);
-
-	/// Parse [`Source`] into a new [`Document`]
-	fn parse<'a>(
-		&self,
-		source: Rc<dyn Source>,
-		parent: Option<&'a dyn Document<'a>>,
-	) -> Box<dyn Document<'a> + 'a>;
-
-	/// Parse [`Source`] into an already existing [`Document`]
-	fn parse_into<'a>(&self, source: Rc<dyn Source>, document: &'a dyn Document<'a>);
 }

src/parser/rule.rs

@@ -4,6 +4,8 @@ use super::source::Source;
 use super::source::Token;
 use crate::document::document::Document;
 use ariadne::Report;
+use downcast_rs::impl_downcast;
+use downcast_rs::Downcast;
 use mlua::Function;
 use mlua::Lua;
 
@@ -11,11 +13,11 @@ use std::any::Any;
 use std::ops::Range;
 use std::rc::Rc;
 
-pub trait Rule {
+pub trait Rule: Downcast {
 	/// Returns rule's name
 	fn name(&self) -> &'static str;
 	/// Finds the next match starting from [`cursor`]
-	fn next_match(&self, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)>;
+	fn next_match(&self, parser: &dyn Parser, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)>;
 	/// Callback when rule matches
 	fn on_match<'a>(
 		&self,
@@ -33,6 +35,7 @@ pub trait Rule {
 	/// Registers default layouts
 	fn register_layouts(&self, _parser: &dyn Parser) {}
 }
+impl_downcast!(Rule);
 
 impl core::fmt::Debug for dyn Rule {
 	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
@@ -61,13 +64,13 @@ pub trait RegexRule {
 	fn register_layouts(&self, _parser: &dyn Parser) {}
 }
 
-impl<T: RegexRule> Rule for T {
+impl<T: RegexRule + 'static> Rule for T {
 	fn name(&self) -> &'static str {
 		RegexRule::name(self)
 	}
 
 	/// Finds the next match starting from [`cursor`]
-	fn next_match(&self, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> {
+	fn next_match(&self, _parser: &dyn Parser, cursor: &Cursor) -> Option<(usize, Box<dyn Any>)> {
 		let content = cursor.source.content();
 		let mut found: Option<(usize, usize)> = None;
 		self.regexes().iter().enumerate().for_each(|(id, re)| {