name: "Build"
on:
  pull_request:
  push:

env:
  RUNNER_TOOL_CACHE: /toolcache

jobs:
  determine-hosts:
    name: "Determining hosts to build"
    runs-on: ubuntu-latest
    container:
      image: catthehacker/ubuntu:act-latest
    outputs:
      hosts: ${{ steps.hosts.outputs.hostnames }}
    steps:
      - uses: actions/checkout@v5
      - uses: https://github.com/cachix/install-nix-action@v31
        with:
          nix_path: nixpkgs=channel:nixos-unstable
      - name: "Determine hosts"
        id: hosts
        run: |
          hosts="$(nix eval .#nixosConfigurations --apply builtins.attrNames --json)"
          echo "${hosts}"
          echo "hostnames=${hosts}" >> $GITHUB_OUTPUT
      - name: "List hosts of step"
        run: |
          echo "${{ steps.hosts.outputs.hostnames }}"

  build:
    runs-on: ubuntu-latest
    container:
      image: catthehacker/ubuntu:act-latest
    needs: determine-hosts
    strategy:
      matrix:
        hostname: ${{ fromJSON(needs.determine-hosts.outputs.hosts) }}

    steps:
      - uses: actions/checkout@v5
      - uses: https://github.com/cachix/install-nix-action@v31
        with:
          nix_path: nixpkgs=channel:nixos-unstable
      - name: "Debug needs outputs"
        run: |
          echo "${{ needs.determine-hosts.outputs }}"
      - name: Debug Matrix
        run: |
          echo "The matrix value is: ${{ matrix.hostname }}"
      - name: "Define host"
        run: |
          echo "Building for: ${{ matrix.hostname }}"
      - run: |
          nixos-rebuild build --flake ".#${{ matrix.hostname }}"