Add support for nightly builds

.github/workflows/build.yml

@@ -4,6 +4,8 @@ on:
   push:
     tags:
       - '*'
+  schedule:
+    - cron: '*/15 * * * *'
 
 jobs:
   build:
@@ -30,10 +32,30 @@ jobs:
     - name: Check out code
       uses: actions/checkout@v4
 
+    - name: Check for New Commits (Nightly Only)
+      id: check
+      if: github.event_name == 'schedule'
+      continue-on-error: false
+      run: |
+        # 3AM CET
+        # date -d 'yesterday' +%Y-%m-%dT02:00:0
+        since="$(date -d 'yesterday' +%Y-%m-%d) 02:00:00"
+        count=$(git rev-list --count --since="$since" --until=now HEAD)
+        if [ "$count" -gt 0 ]; then
+          echo "new_commits=true" >> $GITHUB_OUTPUT
+        else
+          echo "no new commits found for nightly build"
+          exit 1
+        fi
+
     - name: Generate build variables
       id: prep
       run: |
+        if [ "${{ github.event_name }}" = "schedule" ]; then
+          echo "version=$(date +'%Y.%m.%d-nightly')" >> $GITHUB_OUTPUT
+        else
           echo "version=$(echo ${GITHUB_REF#refs/tags/})" >> $GITHUB_OUTPUT
+        fi
         echo "built_at=$(date +%Y-%m-%dT%H:%M:%S)" >> $GITHUB_OUTPUT
         echo "git_commit=$(git rev-parse HEAD)" >> $GITHUB_OUTPUT
 
@@ -91,7 +113,12 @@ jobs:
     steps:
     - name: Set version
       id: version
-      run: echo "::set-output name=version::$(echo ${GITHUB_REF#refs/tags/})"
+      run: |
+        if [ "${{ github.event_name }}" = "schedule" ]; then
+          echo "version=$(date +'%Y.%m.%d-nightly')" >> $GITHUB_OUTPUT
+        else
+          echo "version=$(echo ${GITHUB_REF#refs/tags/})" >> $GITHUB_OUTPUT
+        fi
 
     - name: Download artifacts
       uses: actions/download-artifact@v3