From fb8f83a51871c2cf411b47c00f3232bf0cbd450e Mon Sep 17 00:00:00 2001
From: Luca Palmieri <20745048+LukeMathWalker@users.noreply.github.com>
Date: Tue, 13 Aug 2024 15:53:43 +0200
Subject: [PATCH] Add ePUB format (#130)

---
 .github/workflows/ci.yml | 15 ++++++++++--
 book/book.toml           | 50 +++++++++++++++++++++++++++++-----------
 book/metadata.yml        |  4 ++++
 3 files changed, 54 insertions(+), 15 deletions(-)
 create mode 100644 book/metadata.yml

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8ccd0bd..74683de 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,11 +20,11 @@ jobs:
         run: cargo install --path helpers/mdbook-exercise-linker
       - name: Install link shortener plugin
         run: cargo install --path helpers/mdbook-link-shortener
-      - name: Install mdbook-pandoc and related dependencies
+      - name: Install mdbook-pandoc, calibre and related dependencies
         run: |
           cargo install mdbook-pandoc --locked --version 0.7.1
           sudo apt-get update
-          sudo apt-get install -y fonts-noto
+          sudo apt-get install -y fonts-noto calibre
           
           export PANDOC_VERSION=3.3
           curl -LsSf https://github.com/jgm/pandoc/releases/download/${PANDOC_VERSION}/pandoc-${PANDOC_VERSION}-linux-amd64.tar.gz | tar zxf -
@@ -70,6 +70,13 @@ jobs:
         run: |
           cd book
           mdbook build
+      - name: Convert HTML to ePUB
+        run: |
+          cd book/book/pandoc/html
+          sed -i 's|<code>\\newpage</code>{=latex}||g' 100-exercises-to-learn-rust.html
+          ebook-convert 100-exercises-to-learn-rust.html 100-exercises-to-learn-rust.epub \
+            --embed-all-fonts \
+            --subset-embedded-fonts
       - name: Link Checker
         uses: lycheeverse/lychee-action@v1
         with:
@@ -94,6 +101,10 @@ jobs:
         with:
           name: paperback
           path: book/book/pandoc/paperback/100-exercises-to-learn-rust.pdf
+      - uses: actions/upload-artifact@v4
+        with:
+          name: ePUB
+          path: book/book/pandoc/html/100-exercises-to-learn-rust.epub
 
   is_fresh:
     runs-on: ubuntu-latest
diff --git a/book/book.toml b/book/book.toml
index e1abf43..c739aa6 100644
--- a/book/book.toml
+++ b/book/book.toml
@@ -5,6 +5,19 @@ multilingual = false
 src = "src"
 title = "100 Exercises To Learn Rust"
 
+[preprocessor.exercise-linker]
+exercise_root_url = "https://github.com/mainmatter/100-exercises-to-learn-rust/tree/main/exercises"
+
+[preprocessor.link-shortener]
+base_url = "https://ruex.io"
+renderers = ["pandoc"]
+mapping = "link2alias.json"
+verify = false
+after = ["exercise-linker"]
+
+[output.html]
+git-repository-url = "https://github.com/mainmatter/100-exercises-to-learn-rust"
+
 [output.pandoc]
 optional = true
 hosted-html = "https://rust-exercises.com/100-exercises/"
@@ -16,9 +29,9 @@ highlight-style = "tango"
 # We use `lualatext` because, right now, it's the only engine
 # that supports fallback fonts, which we need for emojis.
 pdf-engine = "lualatex"
+metadata-file = "metadata.yml"
 
 [output.pandoc.profile.pdf.variables]
-subtitle = "A hands-on course by Mainmatter"
 # You can get these fonts here: https://fonts.google.com/selection?query=noto+color+
 mainfont = "Noto Serif"
 sansfont = "Noto Sans"
@@ -43,12 +56,12 @@ header-includes = [
 output-file = "100-exercises-to-learn-rust.pdf"
 to = "latex"
 highlight-style = "monochrome"
+metadata-file = "metadata.yml"
 # We use `lualatext` because, right now, it's the only engine
 # that supports fallback fonts, which we need for emojis.
 pdf-engine = "lualatex"
 
 [output.pandoc.profile.paperback.variables]
-subtitle = "A hands-on course by Mainmatter"
 # You can get these fonts here: https://fonts.google.com/selection?query=noto+color+
 mainfont = "Noto Serif"
 sansfont = "Noto Sans"
@@ -68,15 +81,26 @@ header-includes = [
 ]
 links-as-notes = true
 
-[output.html]
-git-repository-url = "https://github.com/mainmatter/100-exercises-to-learn-rust"
+# We go through HTML, rather than directly to ePUB, since routing
+# Pandoc's HTML through Calibre's ePUB converter gives us better results.
+[output.pandoc.profile.html]
+output-file = "100-exercises-to-learn-rust.html"
+to = "html"
+highlight-style = "monochrome"
+embed-resources = true
+standalone = true
+metadata-file = "metadata.yml"
 
-[preprocessor.exercise-linker]
-exercise_root_url = "https://github.com/mainmatter/100-exercises-to-learn-rust/tree/main/exercises"
-
-[preprocessor.link-shortener]
-base_url = "https://ruex.io"
-renderers = ["pandoc"]
-mapping = "link2alias.json"
-verify = false
-after = ["exercise-linker"]
+[output.pandoc.profile.html.variables]
+# You can get these fonts here: https://fonts.google.com/selection?query=noto+color+
+mainfont = "Noto Serif"
+sansfont = "Noto Sans"
+monofont = "Noto Sans Mono"
+mainfontfallback = ["Noto Color Emoji:mode=harf"]
+sansfontfallback = ["Noto Color Emoji:mode=harf"]
+monofontfallback = [
+  "Noto Color Emoji:mode=harf",
+]
+linkcolor = "blue"
+urlcolor = "blue"
+urlstyle = "rm"
diff --git a/book/metadata.yml b/book/metadata.yml
new file mode 100644
index 0000000..0ab8aaf
--- /dev/null
+++ b/book/metadata.yml
@@ -0,0 +1,4 @@
+title: "100 Exercises To Learn Rust"
+subtitle: "A hands-on course by Mainmatter"
+author: "Luca Palmieri"
+keywords: ["Rust", "Programming"]
\ No newline at end of file