CI: move the preview script to an action

.forgejo/workflows/pr.yml

@@ -26,8 +26,7 @@ jobs:
           cd /tmp/website
           corepack enable
           pnpm install --frozen-lockfile
-      - name: preview
-        if: ${{ secrets.WEBSITETOKEN != '' }}
+      - name: build
         run: |
           cd /tmp/website
           colon=':'
@@ -36,25 +35,15 @@ jobs:
           cat src/config.mjs
           corepack enable
           pnpm run build
-          git clone https://forgejo-website:${{ secrets.WEBSITETOKEN }}@codeberg.org/forgejo/pages /tmp/pages
-          git -C /tmp/pages switch -C $branch
-          mv /tmp/pages/.git dist
-          cd dist
-          git config user.email "ci@forgejo.org" ; git config user.name "forgejo-website"
-          git add .
-          git diff-index --quiet HEAD || git commit -m 'publish' -a
-          remote_branch_present=$(git show-branch refs/remotes/origin/$branch 2>/dev/null || true)
-          git push --force origin $branch
-
-          # Add PR comment with preview links on PR which were not already deployed
-          if [ ! "$remote_branch_present" ]; then
-            echo -n '{"body": "Preview ready: https://forgejo.codeberg.page/@'"$branch"'/' > comment.json
-
-            # Add link to 5 first pages with more than 100 changes
-            # awk is actually mawk, which does not support regex interval {n,m}
-            git diff --stat origin/main | awk '/\.html *\| *[0-9][0-9][0-9]+ [+-]*$/ { print $3, $1 }' | sort -rn | head -n5 | cut -d" " -f2 | sed 's/index\.html//' | sed 's#^#\\\\nhttps://forgejo.codeberg.page/@'"$branch"'/#' | tr -d '\n' >> comment.json
-            echo '"}' >> comment.json
-
-            # Post PR comment
-            curl -d @comment.json -H "Content-Type: application/json" -X POST "https://forgejo-website:${{ secrets.WEBSITETOKEN }}@codeberg.org/api/v1/repos/forgejo/docs/issues/${{ env.GITHUB_REF_NAME }}/comments"
-          fi
+          mv dist /tmp
+      - name: preview
+        if: ${{ secrets.WEBSITETOKEN != '' }}
+        uses: https://code.forgejo.org/forgejo/action-website-preview@main
+        with:
+          directory: /tmp/dist
+          name: 'docs_pull_${{ env.GITHUB_REF_NAME }}'
+          pages-token: ${{ secrets.WEBSITETOKEN }}
+          repository: forgejo/docs
+          repository-host: codeberg.org
+          repository-token: ${{ secrets.WEBSITETOKEN }}
+          pr-number: ${{ env.GITHUB_REF_NAME }}