name: Update nix flake inputs

on:
  schedule:
    # Every Sunday at 03:00 UTC
    - cron: "0 3 * * 0"

  workflow_dispatch: {}

jobs:
  flake-update:
    runs-on: ubuntu-latest

    permissions:
      contents: write

    steps:
      - name: Git Config
        run: |
          git config user.name "gitea-actions"
          git config user.email "actions@${GITEA_SERVER_HOST:-gitea.local}"

      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Install Nix
        uses: DeterminateSystems/nix-installer-action@v12
        with:
          nix_path: nixpkgs=channel:nixos-unstable
          extra_conf: |
            experimental-features = nix-command flakes

      - name: Update flake.lock
        run: nix flake update

      - name: Commit flake.lock
        run: |
          if git diff --quiet flake.lock; then
            echo "No changes to flake.lock"
            exit 0
          fi

          git add flake.lock
          git commit -m "Update flake inputs"
          git push