From d8a1693dd7356ccbf56992255d5fc170042f8854 Mon Sep 17 00:00:00 2001
From: Mylloon <kennel.anri@tutanota.com>
Date: Wed, 19 Apr 2023 18:36:52 +0200
Subject: [PATCH] * Doesnt convert in Rust the latex * add math detection * fix
 mermaid and code detection

---
 Cargo.lock      |  7 -----
 Cargo.toml      |  1 -
 src/template.rs | 72 +++++++++++++++++++++++++++++++++++++------------
 3 files changed, 55 insertions(+), 25 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 11e848f..3ed4cf5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -597,7 +597,6 @@ dependencies = [
  "actix-web",
  "cached",
  "glob",
- "latex2mathml",
  "markdown",
  "minify-html",
  "ramhorns",
@@ -958,12 +957,6 @@ version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d4345964bb142484797b161f473a503a434de77149dd8c7427788c6e13379388"
 
-[[package]]
-name = "latex2mathml"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "678cf5bdb3ba63a264e6e0c9eee36538ca1d2da0afa4dd801c1f96309e710765"
-
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
diff --git a/Cargo.toml b/Cargo.toml
index 1be210d..e9612eb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,5 +20,4 @@ serde_yaml = "0.9"
 minify-html = "0.10.8"
 glob = "0.3.1"
 markdown = "1.0.0-alpha.7"
-latex2mathml = "0.2.3"
 reqwest = { version = "0.11", features = ["json"] }
diff --git a/src/template.rs b/src/template.rs
index bd7b560..7c06d9e 100644
--- a/src/template.rs
+++ b/src/template.rs
@@ -1,3 +1,4 @@
+use markdown::mdast::Node;
 use ramhorns::{Content, Ramhorns};
 use serde::Deserialize;
 use std::fs;
@@ -61,6 +62,7 @@ pub struct FileMetadata {
 #[derive(Content)]
 pub struct Metadata {
     pub info: FileMetadata,
+    pub math: bool,
     pub mermaid: bool,
     pub syntax_highlight: bool,
 }
@@ -80,12 +82,11 @@ pub fn read_md_file(filename: &str) -> Option<File> {
 }
 
 pub fn read_md(raw_text: &str) -> File {
-    // Transform LaTeX to MathML
-    let text = latex2mathml::replace(raw_text).unwrap_or(raw_text.to_string());
-
     let parse_option = markdown::ParseOptions {
         constructs: markdown::Constructs {
             frontmatter: true,
+            math_text: true,
+            math_flow: true,
             ..markdown::Constructs::gfm()
         },
         ..markdown::ParseOptions::gfm()
@@ -96,40 +97,39 @@ pub fn read_md(raw_text: &str) -> File {
         ..markdown::CompileOptions::gfm()
     };
 
-    let md_tree = markdown::to_mdast(&text, &parse_option).unwrap();
+    let md_tree = markdown::to_mdast(raw_text, &parse_option).unwrap();
     let md_nodes = md_tree.children().unwrap();
     let metadata;
     let presence_mermaid;
+    let presence_math;
     let presence_code;
     if md_nodes.is_empty() {
         metadata = FileMetadata::default();
         presence_mermaid = false;
+        presence_math = false;
         presence_code = false;
     } else {
         metadata = match &md_nodes[0] {
-            markdown::mdast::Node::Yaml(v) => FrontMatter::Yaml(&v.value).parse(),
-            markdown::mdast::Node::Toml(v) => FrontMatter::Toml(&v.value).parse(),
-            markdown::mdast::Node::MdxjsEsm(v) => FrontMatter::Json(&v.value).parse(),
+            Node::Yaml(v) => FrontMatter::Yaml(&v.value).parse(),
+            Node::Toml(v) => FrontMatter::Toml(&v.value).parse(),
+            Node::MdxjsEsm(v) => FrontMatter::Json(&v.value).parse(),
             _ => FileMetadata::default(),
         };
 
+        // Find if document contains maths
+        presence_math = check_math(md_nodes);
+
         // Find if document contains mermaid diagram
-        let mermaid = Some(String::from("mermaid"));
-        presence_mermaid = md_nodes.iter().any(|x| match x {
-            markdown::mdast::Node::Code(code) => code.lang == mermaid,
-            _ => false,
-        });
+        let mermaid = String::from("mermaid");
+        presence_mermaid = check_mermaid(md_nodes, mermaid.clone());
 
         // Find if document contains code to highlight
-        presence_code = md_nodes.iter().any(|x| match x {
-            markdown::mdast::Node::Code(code) => code.lang != mermaid,
-            _ => false,
-        });
+        presence_code = check_code(md_nodes, vec![mermaid]);
     }
 
     // Convert to HTML
     let html = markdown::to_html_with_options(
-        &text,
+        raw_text,
         &markdown::Options {
             parse: parse_option,
             compile: compile_option,
@@ -140,9 +140,47 @@ pub fn read_md(raw_text: &str) -> File {
     File {
         metadata: Metadata {
             info: metadata,
+            math: presence_math,
             mermaid: presence_mermaid,
             syntax_highlight: presence_code,
         },
         content: html,
     }
 }
+
+/// Check recursively if maths is in the AST
+fn check_math(vec: &[Node]) -> bool {
+    vec.iter().any(|x| {
+        matches!(x, Node::Math(_) | Node::InlineMath(_))
+            || match x.children() {
+                Some(children) => check_math(children),
+                None => false,
+            }
+    })
+}
+
+/// Recursively check whether mermaid diagrams are in the AST
+fn check_mermaid(vec: &[Node], mermaid_str: String) -> bool {
+    vec.iter().any(|x| match x {
+        Node::Code(code) => code.lang == Some(mermaid_str.clone()),
+        _ => false,
+    } || match x.children() {
+        Some(children) => check_mermaid(children, mermaid_str.clone()),
+        None => false
+    })
+}
+
+/// Recursively check if code is in the AST
+fn check_code(vec: &[Node], blacklist: Vec<String>) -> bool {
+    vec.iter().any(|x| match x {
+        Node::InlineCode(_) => true,
+        Node::Code(code) => match &code.lang {
+            Some(lang) => !blacklist.contains(lang),
+            None => true,
+        },
+        _ => false,
+    } || match x.children() {
+        Some(children) => check_code(children, blacklist.clone()),
+        None => false
+    })
+}