# Optional / not on every PR: bootstrap selfhost determinism (make selfhost-loop).
# Default PR CI is .github/workflows/ci.yml (`make test`).
# Fixed-point gen2 vs gen3: BUX_SELFHOST_FIXED_POINT=1 (workflow_dispatch input).
name: selfhost-loop

on:
  workflow_dispatch:
    inputs:
      fixed_point:
        description: "Also run fixed-point buxc2→buxc3→buxc4 (gen2 vs gen3)"
        type: boolean
        default: false
  schedule:
    # Sundays 06:00 UTC
    - cron: "0 6 * * 0"
  push:
    branches: [main]
    paths:
      - "src/**"
      - "lib/**"
      - "rt/**"
      - "bootstrap/**"
      - "tools/selfhost_loop.sh"
      - "Makefile"
      - ".github/workflows/selfhost-loop.yml"

concurrency:
  group: selfhost-loop-${{ github.ref }}
  cancel-in-progress: true

env:
  NIM_VERSION: "2.0.8"
  NIM_INSTALL_DIR: ".nim_runtime"

jobs:
  selfhost-loop:
    name: bootstrap determinism
    runs-on: ubuntu-latest
    timeout-minutes: 45
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Cache Nim toolchain
        id: cache-nim
        uses: actions/cache@v4
        with:
          path: ${{ env.NIM_INSTALL_DIR }}
          key: ${{ runner.os }}-nim-${{ env.NIM_VERSION }}-v1

      - name: Install Nim
        if: steps.cache-nim.outputs.cache-hit != 'true'
        uses: jiro4989/setup-nim-action@v2
        with:
          nim-version: ${{ env.NIM_VERSION }}
          nim-install-directory: ${{ env.NIM_INSTALL_DIR }}
          repo-token: ${{ secrets.GITHUB_TOKEN }}

      - name: PATH for cached Nim
        if: steps.cache-nim.outputs.cache-hit == 'true'
        run: |
          echo "$PWD/${{ env.NIM_INSTALL_DIR }}/bin" >> "$GITHUB_PATH"
          echo "$HOME/.nimble/bin" >> "$GITHUB_PATH"

      - name: Cache nimcache
        uses: actions/cache@v4
        with:
          path: nimcache
          key: ${{ runner.os }}-nimcache-loop-${{ hashFiles('bootstrap/**/*.nim', 'src/**/*.bux') }}-v1
          restore-keys: |
            ${{ runner.os }}-nimcache-loop-
            ${{ runner.os }}-nimcache-build-

      - name: Install build deps
        run: |
          sudo apt-get update
          sudo apt-get install -y --no-install-recommends gcc make binutils libssl-dev

      - name: Selfhost loop
        run: |
          if [ "${{ github.event_name }}" = "workflow_dispatch" ] && [ "${{ inputs.fixed_point }}" = "true" ]; then
            export BUX_SELFHOST_FIXED_POINT=1
            echo "Fixed-point mode enabled (experimental)"
          fi
          make selfhost-loop

      - name: Upload C on failure
        if: failure()
        uses: actions/upload-artifact@v4
        with:
          name: selfhost-loop-c
          path: |
            build/selfhost-loop-a/build/main.c
            build/selfhost-loop-b/build/main.c
          if-no-files-found: ignore