From 9a69ea655d96aa8441a3650387fbec7f3f06bc0b Mon Sep 17 00:00:00 2001
From: simonsan <14062932+simonsan@users.noreply.github.com>
Date: Sun, 17 Mar 2024 03:25:39 +0100
Subject: [PATCH] feat: use mdbook-last-changed to indicate when a file has
 been last updated

---
 .env                                        | 1 +
 .github/workflows/install-mdbook/action.yml | 9 ++++++++-
 book.toml                                   | 9 ++++++++-
 styles/last-changed.css                     | 7 +++++++
 4 files changed, 24 insertions(+), 2 deletions(-)
 create mode 100644 styles/last-changed.css

diff --git a/.env b/.env
index a2b75bbb..193c72da 100644
--- a/.env
+++ b/.env
@@ -1,3 +1,4 @@
 MDBOOK_VERSION=0.4.37
 MDBOOK_I18N_HELPERS_VERSION=0.3.2
 MDBOOK_PANDOC_VERSION=0.6.0
+MDBOOK_LAST_CHANGED_VERSION=0.1.4
diff --git a/.github/workflows/install-mdbook/action.yml b/.github/workflows/install-mdbook/action.yml
index 500f5b68..6cc6d3bf 100644
--- a/.github/workflows/install-mdbook/action.yml
+++ b/.github/workflows/install-mdbook/action.yml
@@ -26,10 +26,17 @@ runs:
         echo "version=$MDBOOK_PANDOC_VERSION" >> $GITHUB_OUTPUT
       shell: bash
 
+    - name: Read mdbook-last-changed version from .env
+      id: mdbook-last-changed-version
+      run: |
+        . ./.env
+        echo "version=$MDBOOK_LAST_CHANGED_VERSION" >> $GITHUB_OUTPUT
+      shell: bash
+
     - name: Install dependencies
       uses: taiki-e/install-action@v2
       with:
-        tool: mdbook@${{ steps.mdbook-version.outputs.version }},mdbook-pandoc@${{ steps.mdbook-pandoc-version.outputs.version }},mdbook-i18n-helpers@${{ steps.mdbook-i18n-helpers-version.outputs.version }}
+        tool: mdbook@${{ steps.mdbook-version.outputs.version }},mdbook-pandoc@${{ steps.mdbook-pandoc-version.outputs.version }},mdbook-i18n-helpers@${{ steps.mdbook-i18n-helpers-version.outputs.version }},mdbook-last-changed@${{ steps.mdbook-last-changed-version.outputs.version }}
 
     - name: Install mdbook-pandoc and related dependencies
       run: |
diff --git a/book.toml b/book.toml
index 34fb1e76..a44e064b 100644
--- a/book.toml
+++ b/book.toml
@@ -23,7 +23,14 @@ site-url = "/patterns/"
 git-repository-url = "https://github.com/rust-unofficial/patterns"
 git-repository-icon = "fa-github"
 edit-url-template = "https://github.com/rust-unofficial/patterns/edit/main/{path}"
-additional-css = ["theme/css/language-picker.css"]
+additional-css = [
+  "./theme/css/language-picker.css",
+  "./styles/last-changed.css",
+]
+
+[preprocessor.last-changed]
+command = "mdbook-last-changed"
+renderer = ["html"]
 
 [output.html.fold]
 enable = true
diff --git a/styles/last-changed.css b/styles/last-changed.css
new file mode 100644
index 00000000..21de8212
--- /dev/null
+++ b/styles/last-changed.css
@@ -0,0 +1,7 @@
+footer {
+  font-size: 0.8em;
+  text-align: center;
+  border-top: 1px solid grey;
+  padding: 1.25em 0;
+  margin-top: 1.25em;
+}