From 00b0dc309e3526a3d725b1dffe2b766715a0747f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dani=C3=ABlle=20Huisman?= <danielle@huisman.me>
Date: Mon, 8 Jul 2024 09:41:53 +0200
Subject: [PATCH] Add cmark to processor

---
 book/mdbook-trunk/Cargo.toml          |  2 +
 book/mdbook-trunk/src/preprocessor.rs | 91 ++++++++++++++++++++++++---
 2 files changed, 85 insertions(+), 8 deletions(-)

diff --git a/book/mdbook-trunk/Cargo.toml b/book/mdbook-trunk/Cargo.toml
index 5d7e5167..0bf7fa2f 100644
--- a/book/mdbook-trunk/Cargo.toml
+++ b/book/mdbook-trunk/Cargo.toml
@@ -12,5 +12,7 @@ version.workspace = true
 [dependencies]
 clap = { version = "4.5.8", features = ["derive"] }
 mdbook = "0.4.40"
+pulldown-cmark = "0.11.0"
+pulldown-cmark-to-cmark = "15.0.1"
 semver = "1.0.23"
 serde_json = "1.0.120"
diff --git a/book/mdbook-trunk/src/preprocessor.rs b/book/mdbook-trunk/src/preprocessor.rs
index 6cfa37cb..f4d97862 100644
--- a/book/mdbook-trunk/src/preprocessor.rs
+++ b/book/mdbook-trunk/src/preprocessor.rs
@@ -1,9 +1,10 @@
 use mdbook::{
     book::{Book, Chapter},
-    errors::Error,
     preprocess::{Preprocessor, PreprocessorContext},
     BookItem,
 };
+use pulldown_cmark::{Event, Parser};
+use pulldown_cmark_to_cmark::cmark;
 
 pub struct TrunkPreprocessor;
 
@@ -12,7 +13,25 @@ impl TrunkPreprocessor {
         Self
     }
 
-    fn process_chapter(&self, _chapter: &mut Chapter) {}
+    fn process_chapter(&self, chapter: &mut Chapter) -> Result<(), mdbook::errors::Error> {
+        let mut buf = String::with_capacity(chapter.content.len());
+
+        let events = Parser::new(&chapter.content).map(|event| {
+            println!("{:?}", event);
+
+            if let Event::Text(_text) = &event {}
+
+            event
+        });
+
+        if let Err(err) = cmark(events, &mut buf) {
+            Err(err.into())
+        } else {
+            chapter.content = buf;
+
+            Ok(())
+        }
+    }
 }
 
 impl Default for TrunkPreprocessor {
@@ -26,14 +45,14 @@ impl Preprocessor for TrunkPreprocessor {
         "trunk"
     }
 
-    fn run(&self, _ctx: &PreprocessorContext, book: Book) -> Result<Book, Error> {
+    fn run(&self, _ctx: &PreprocessorContext, book: Book) -> Result<Book, mdbook::errors::Error> {
         let mut book = book.clone();
 
-        book.for_each_mut(|section| match section {
-            BookItem::Chapter(chapter) => self.process_chapter(chapter),
-            BookItem::Separator => {}
-            BookItem::PartTitle(_) => {}
-        });
+        for section in &mut book.sections {
+            if let BookItem::Chapter(chapter) = section {
+                self.process_chapter(chapter)?;
+            }
+        }
 
         Ok(book)
     }
@@ -42,3 +61,59 @@ impl Preprocessor for TrunkPreprocessor {
         renderer == "html"
     }
 }
+
+#[cfg(test)]
+mod test {
+    use mdbook::preprocess::CmdPreprocessor;
+
+    use super::*;
+
+    #[test]
+    fn test_run() {
+        let input_json = r##"[
+            {
+                "root": "/path/to/book",
+                "config": {
+                    "book": {
+                        "authors": ["AUTHOR"],
+                        "language": "en",
+                        "multilingual": false,
+                        "src": "src",
+                        "title": "TITLE"
+                    },
+                    "preprocessor": {
+                        "nop": {}
+                    }
+                },
+                "renderer": "html",
+                "mdbook_version": "0.4.21"
+            },
+            {
+                "sections": [
+                    {
+                        "Chapter": {
+                            "name": "Chapter 1",
+                            "content": "# Chapter 1\n{{#trunk example.rs}}\n",
+                            "number": [1],
+                            "sub_items": [],
+                            "path": "chapter_1.md",
+                            "source_path": "chapter_1.md",
+                            "parent_names": []
+                        }
+                    }
+                ],
+                "__non_exhaustive": null
+            }
+        ]"##
+        .as_bytes();
+
+        let (ctx, book) = CmdPreprocessor::parse_input(input_json).unwrap();
+        let expected_book = book.clone();
+
+        let result = TrunkPreprocessor::new().run(&ctx, book);
+        assert!(result.is_ok());
+
+        let actual_book = result.unwrap();
+        assert_eq!(actual_book, expected_book);
+    }
+}