name: Nix Flake Update

on:
  schedule:
    - cron: "0 3 * * 0"
  workflow_dispatch: {}

jobs:
  update:
    runs-on: ubuntu-latest
    if: github.ref == 'refs/heads/main'
    steps:
      - uses: actions/checkout@v4

      - name: Install Nix
        run: |
          curl --proto '=https' --tlsv1.2 -sSf -L https://install.determinate.systems/nix | sh -s -- install linux --no-confirm --init none
          echo "/nix/var/nix/profiles/default/bin" >> "$GITHUB_PATH"

      - name: Update flake inputs
        run: nix flake update

      - name: Commit and push changes
        run: |
          git diff --quiet flake.lock && echo "No changes" && exit 0
          git config user.name "Gitea Actions"
          git config user.email "actions@gitea.local"
          git add flake.lock
          git commit -m "chore: nix flake update $(date -I)"
          git push