From ee76acc9c938a070ab82bec48ea4f0df35470402 Mon Sep 17 00:00:00 2001
From: Michal Sojka <michal.sojka@cvut.cz>
Date: Wed, 18 Sep 2024 09:05:36 +0200
Subject: [PATCH] Update rosdistro only when necessary

---
 .github/workflows/update.yml | 23 +++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/update.yml b/.github/workflows/update.yml
index 1c4661e..26ca830 100644
--- a/.github/workflows/update.yml
+++ b/.github/workflows/update.yml
@@ -1,7 +1,7 @@
 name: Update rosdistro
 on:
   schedule:
-    - cron: "0 12 * * FRI"
+    - cron: "0 12 * * *"
   workflow_dispatch:
 jobs:
   update:
@@ -15,7 +15,26 @@ jobs:
           git config user.email 'github-actions[bot]@users.noreply.github.com'
       - name: Update rosdistro
         run: |
-          nix flake update rosdistro --commit-lock-file
+          nix build .#rosdistro --out-link /tmp/rosdistro-old
+          nix flake update rosdistro
+          nix build .#rosdistro --out-link /tmp/rosdistro-new
+          grep -Rh nixos: /tmp/rosdistro-old > /tmp/rosdistro-old.txt
+          grep -Rh nixos: /tmp/rosdistro-new > /tmp/rosdistro-new.txt
+          git reset --hard
+          if ! git diff /tmp/rosdistro-old.txt /tmp/rosdistro-new.txt > /tmp/rosdistro-diff; then
+            # redo update with nice commit message
+            nix flake update rosdistro --commit-lock-file
+            GIT_EDITOR='sed -i -e "1crosdistro update"' git commit --amend
+            GIT_EDITOR='sed -i -e "\$R/tmp/rosdistro-diff"' git commit --amend
+            cat <<EOF > /tmp/.body
+            Diff:
+            ```diff
+            $(cat /tmp/rosdistro-diff)
+            ```
+          EOF
+          else
+            echo "No relevant changes"
+          fi
           git show --format='%b' --no-patch > /tmp/.body
       - name: Create Pull Request
         uses: peter-evans/create-pull-request@v7