# Reference: https://github.com/ryoppippi/dotfiles/blob/main/.github/workflows/nix-build.yaml
name: "CI: Nix"
on:
  push:
    branches:
      - main
    paths:
      - .gitignore
      - AGENTS.md
      - README.md
      - "docs/**"
      - flake.nix
      - flake.lock
      - ".codex/**"
      - ".github/**"
      - ".vscode/**"
      - "flake/**"
      - "hosts/**"
      - "libs/**"
      - "modules/**"
      - "opencode.json"
      - "overlays/**"
      - "scripts/**"
      - "shells/**"
      - "skills/**"
      - "tests/**"
  pull_request:
    paths:
      - .gitignore
      - AGENTS.md
      - README.md
      - "docs/**"
      - flake.nix
      - flake.lock
      - ".codex/**"
      - ".github/**"
      - ".vscode/**"
      - "flake/**"
      - "hosts/**"
      - "libs/**"
      - "modules/**"
      - "opencode.json"
      - "overlays/**"
      - "scripts/**"
      - "shells/**"
      - "skills/**"
      - "tests/**"
  workflow_dispatch:
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
permissions:
  contents: read
jobs:
  validate:
    name: Plan, lint, and evaluate
    runs-on: ubuntu-latest
    timeout-minutes: 120
    outputs:
      build_linux: ${{ steps.plan.outputs.build_linux }}
      build_darwin: ${{ steps.plan.outputs.build_darwin }}
      nix_validation: ${{ steps.plan.outputs.nix_validation }}
    steps:
      - name: Checkout repository
        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7
        with:
          fetch-depth: 0
      - name: Setup Nix
        uses: ./.github/actions/setup-nix
      - name: Plan validation
        id: plan
        env:
          PR_BASE_SHA: ${{ github.event.pull_request.base.sha }}
          PUSH_BASE_SHA: ${{ github.event.before }}
        shell: bash
        run: |
          set -euo pipefail

          case "${{ github.event_name }}" in
            pull_request)
              plan="$(nix run .#check -- plan --base "$PR_BASE_SHA" --json)"
              ;;
            push)
              plan="$(nix run .#check -- plan --base "$PUSH_BASE_SHA" --json)"
              ;;
            *)
              plan="$(nix run .#check -- plan --all-files --all-hosts --json)"
              ;;
          esac

          printf '%s\n' "$plan"
          nix_validation="$(jq -r '.requiresNixValidation' <<<"$plan")"

          if [[ "${{ github.event_name }}" == "pull_request" ]]; then
            build_linux="$(jq -r '.nativeBuildSystems["x86_64-linux"] // false' <<<"$plan")"
            build_darwin="$(jq -r '.nativeBuildSystems["aarch64-darwin"] // false' <<<"$plan")"
          else
            build_linux="$nix_validation"
            build_darwin="$nix_validation"
          fi

          {
            echo "nix_validation=$nix_validation"
            echo "build_linux=$build_linux"
            echo "build_darwin=$build_darwin"
          } >> "$GITHUB_OUTPUT"
      - name: Run fast checks
        env:
          PR_BASE_SHA: ${{ github.event.pull_request.base.sha }}
          PUSH_BASE_SHA: ${{ github.event.before }}
        shell: bash
        run: |
          set +e
          set -uo pipefail
          case "${{ github.event_name }}" in
            pull_request)
              nix run .#check -- fast --base "$PR_BASE_SHA"
              ;;
            push)
              nix run .#check -- fast --base "$PUSH_BASE_SHA"
              ;;
            *)
              nix run .#check -- fast --all-files
              ;;
          esac
          status=$?
          if (( status != 0 )); then
            git diff -- .
            exit "$status"
          fi
      - name: Evaluate configurations
        if: steps.plan.outputs.nix_validation == 'true' || github.event_name == 'workflow_dispatch'
        env:
          PR_BASE_SHA: ${{ github.event.pull_request.base.sha }}
          PUSH_BASE_SHA: ${{ github.event.before }}
        shell: bash
        run: |
          set -euo pipefail
          case "${{ github.event_name }}" in
            pull_request)
              nix run .#check -- eval --base "$PR_BASE_SHA"
              ;;
            push)
              nix run .#check -- eval --base "$PUSH_BASE_SHA" --all-systems
              ;;
            *)
              nix run .#check -- eval --all-hosts --all-systems
              ;;
          esac
  build-linux:
    name: Build Linux checks
    needs: validate
    if: needs.validate.outputs.build_linux == 'true'
    runs-on: ubuntu-latest
    timeout-minutes: 180
    steps:
      - name: Checkout repository
        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7
        with:
          fetch-depth: 0
      - name: Setup Nix
        uses: ./.github/actions/setup-nix
      - name: Build affected Linux checks
        if: github.event_name == 'pull_request'
        env:
          PR_BASE_SHA: ${{ github.event.pull_request.base.sha }}
        shell: bash
        run: |
          set -euo pipefail
          nix run .#check -- build --base "$PR_BASE_SHA"
      - name: Build all Linux checks
        if: github.event_name != 'pull_request'
        uses: ./.github/actions/check-nixos
  build-darwin:
    name: Build Darwin checks
    needs: validate
    if: needs.validate.outputs.build_darwin == 'true'
    runs-on: macos-15
    timeout-minutes: 180
    steps:
      - name: Checkout repository
        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7
        with:
          fetch-depth: 0
      - name: Setup Nix
        uses: ./.github/actions/setup-nix
      - name: Build affected Darwin checks
        if: github.event_name == 'pull_request'
        env:
          PR_BASE_SHA: ${{ github.event.pull_request.base.sha }}
        shell: bash
        run: |
          set -euo pipefail
          nix run .#check -- build --base "$PR_BASE_SHA"
      - name: Build all Darwin checks
        if: github.event_name != 'pull_request'
        shell: bash
        run: |
          set -euo pipefail
          nix run .#nix-fast-build -- \
            --flake .#checks.aarch64-darwin \
            --skip-cached \
            --no-nom \
            --no-link