From 48808bfb75712fbaf49c5dfeeeb560725f0b5b62 Mon Sep 17 00:00:00 2001
From: Konstantin Podsvirov <konstantin@podsvirov.pro>
Date: Thu, 3 Nov 2022 01:47:45 +0300
Subject: [PATCH] Configurable MathJax Support

---
 guide/book.toml                              |  4 +++-
 src/config.rs                                | 25 ++++++++++++++++++++
 src/renderer/html_handlebars/hbs_renderer.rs | 10 ++++++++
 src/theme/index.hbs                          | 21 ++++++++++++++++
 4 files changed, 59 insertions(+), 1 deletion(-)

diff --git a/guide/book.toml b/guide/book.toml
index 025efc0b..ca54cca9 100644
--- a/guide/book.toml
+++ b/guide/book.toml
@@ -8,11 +8,13 @@ language = "en"
 edition = "2018"
 
 [output.html]
-mathjax-support = true
 site-url = "/mdBook/"
 git-repository-url = "https://github.com/rust-lang/mdBook/tree/master/guide"
 edit-url-template = "https://github.com/rust-lang/mdBook/edit/master/guide/{path}"
 
+[output.html.mathjax]
+enable = true
+
 [output.html.playground]
 editable = true
 line-numbers = true
diff --git a/src/config.rs b/src/config.rs
index 0c367d84..8cecb663 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -490,6 +490,8 @@ pub struct HtmlConfig {
     pub curly_quotes: bool,
     /// Should mathjax be enabled?
     pub mathjax_support: bool,
+    /// MathJax settings.
+    pub mathjax: MathJax,
     /// Whether to fonts.css and respective font files to the output directory.
     pub copy_fonts: bool,
     /// An optional google analytics code.
@@ -550,6 +552,7 @@ impl Default for HtmlConfig {
             preferred_dark_theme: None,
             curly_quotes: false,
             mathjax_support: false,
+            mathjax: MathJax::default(),
             copy_fonts: true,
             google_analytics: None,
             additional_css: Vec::new(),
@@ -582,6 +585,28 @@ impl HtmlConfig {
     }
 }
 
+/// Configuration for how to use MathJax.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(default, rename_all = "kebab-case")]
+pub struct MathJax {
+    /// Whether MathJax support is enabled.
+    pub enable: bool,
+    /// Source. Default: "https://cdn.jsdelivr.net/npm/mathjax@3/es5".
+    pub source: Option<String>,
+    /// Configuration. Default: "tex-mml-chtml".
+    pub config: Option<String>,
+}
+
+impl Default for MathJax {
+    fn default() -> Self {
+        Self {
+            enable: false,
+            source: Some(String::from("https://cdn.jsdelivr.net/npm/mathjax@3/es5")),
+            config: Some(String::from("tex-mml-chtml")),
+        }
+    }
+}
+
 /// Configuration for how to render the print icon, print.html, and print.css.
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 #[serde(default, rename_all = "kebab-case")]
diff --git a/src/renderer/html_handlebars/hbs_renderer.rs b/src/renderer/html_handlebars/hbs_renderer.rs
index e170e2fc..227588e5 100644
--- a/src/renderer/html_handlebars/hbs_renderer.rs
+++ b/src/renderer/html_handlebars/hbs_renderer.rs
@@ -679,6 +679,16 @@ fn make_data(
 
     if html_config.mathjax_support {
         data.insert("mathjax_support".to_owned(), json!(true));
+    } else if html_config.mathjax.enable {
+        data.insert("mathjax_enable".to_owned(), json!(true));
+        data.insert(
+            "mathjax_source".to_owned(),
+            json!(html_config.mathjax.source),
+        );
+        data.insert(
+            "mathjax_config".to_owned(),
+            json!(html_config.mathjax.config),
+        );
     }
 
     // This `matches!` checks for a non-empty file.
diff --git a/src/theme/index.hbs b/src/theme/index.hbs
index 6f3948c6..b5ed08f7 100644
--- a/src/theme/index.hbs
+++ b/src/theme/index.hbs
@@ -51,6 +51,24 @@
         {{#if mathjax_support}}
         <!-- MathJax -->
         <script async src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
+        {{else}}
+        {{#if mathjax_enable}}
+        <!-- MathJax -->
+        {{#if is_print}}
+        <script>
+        MathJax = {
+            startup: {
+                pageReady: () => {
+                    return MathJax.startup.defaultPageReady().then(() => {
+                        window.setTimeout(window.print, 100);
+                    });
+                }
+            }
+        };
+        </script>
+        {{/if}}
+        <script id="MathJax-script" async src="{{ mathjax_source }}/{{ mathjax_config }}.js"></script>
+        {{/if}}
         {{/if}}
     </head>
     <body>
@@ -304,6 +322,8 @@
         });
         </script>
         {{else}}
+        {{#if mathjax_enable}}
+        {{else}}
         <script>
         window.addEventListener('load', function() {
             window.setTimeout(window.print, 100);
@@ -311,6 +331,7 @@
         </script>
         {{/if}}
         {{/if}}
+        {{/if}}
 
     </div>
     </body>