name: CI

on:
  pull_request:
  workflow_dispatch:
  workflow_call:
    secrets:
      ATTIC_TOKEN:
        required: false

jobs:
  eval:
    name: Evaluate flake

    runs-on: ubuntu-latest

    outputs:
      matrix: ${{ steps.generate.outputs.matrix }}

    steps:
      - uses: actions/checkout@v4

      - name: Install Nix
        uses: DeterminateSystems/nix-installer-action@v9

      - name: Generate matrix
        id: generate
        run: |
          set -Eeu
          echo "matrix=$(nix eval --show-trace --json .#githubWorkflow.matrix)" >> "$GITHUB_OUTPUT"

  build:
    needs: eval

    strategy:
      fail-fast: false
      matrix: ${{ fromJSON(needs.eval.outputs.matrix) }}

    runs-on: ${{ matrix.os }}

    name: Build (${{matrix.attr}})

    steps:
      - uses: actions/checkout@v4

      - name: Setup Qemu
        if: matrix.arch == 'aarch64'
        uses: docker/setup-qemu-action@v3
        with:
          platforms: "arm64"

      - name: Install Nix
        if: matrix.arch != 'aarch64'
        uses: DeterminateSystems/nix-installer-action@v9

      - name: Install Nix (with aarch64)
        if: matrix.arch == 'aarch64'
        uses: DeterminateSystems/nix-installer-action@v9
        with:
          extra-conf: "extra-platforms = aarch64-linux arm-linux"

      - name: Setup Attic 
        if: github.event_name != 'pull_request'
        uses: ryanccn/attic-action@v0
        with:
          endpoint: https://cache.mydadleft.me
          cache: getchoo
          token: ${{ secrets.ATTIC_TOKEN }}

      - name: Setup Magic Nix Cache
        uses: DeterminateSystems/magic-nix-cache-action@v2

      - name: Build ${{ matrix.attr }}
        run: nix build -L --accept-flake-config --fallback .#${{ matrix.attr }}

  check:
    strategy:
      fail-fast: false
      matrix:
        os: [macos-latest, ubuntu-latest]

    runs-on: ${{ matrix.os }}

    name: Check flake (${{ matrix.os }})

    steps:
      - uses: actions/checkout@v4

      - name: Install Nix
        uses: DeterminateSystems/nix-installer-action@v9

      - name: Setup Attic 
        if: github.event_name != 'pull_request'
        uses: ryanccn/attic-action@v0
        with:
          endpoint: https://cache.mydadleft.me
          cache: getchoo
          token: ${{ secrets.ATTIC_TOKEN }}

      - name: Setup Magic Nix Cache
        uses: DeterminateSystems/magic-nix-cache-action@v2

      - name: Run check
        run: nix flake check -L --accept-flake-config --show-trace

  # https://github.com/orgs/community/discussions/26822#discussioncomment-3305794
  gate:
    name: CI Gate
    needs: [build, check]
    runs-on: ubuntu-latest

    if: always()

    steps:
      - name: Exit with result
        run: |
          buildResult="${{ needs.build.result }}"
          checkResult="${{ needs.check.result }}"

          results=("$buildResult" "$checkResult")

          for result in "${results[@]}"; do [ "$result" != "success" ] && exit 1; done

          exit 0