build-micropython.yml

name: Build MicroPython WebAssembly

on:
  push:
    branches: [main]
    paths:
      - 'micropython'
  workflow_dispatch: {}

permissions:
  contents: write

jobs:
  build:
    runs-on: ubuntu-latest
    
    steps:
      - name: Checkout repository (with submodules)
        uses: actions/checkout@v4
        with:
          submodules: recursive

      - name: Build Docker image
        shell: bash
        run: docker build -f dockerfile -t micropython-wasm-builder .

      - name: Run build in Docker
        shell: bash
        run: |
          # Use github.workspace instead of pwd to guarantee the correct mount path
          docker run --rm -v "${{ github.workspace }}:/app" micropython-wasm-builder
          
          # Fix ownership of files generated by Docker so Git can read/commit them
          sudo chown -R $USER:$USER micropython-build/

      - name: Commit and push build output
        shell: bash
        run: |
          git config --global --add safe.directory "$GITHUB_WORKSPACE"
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
          
          git add micropython-build
          if git diff --cached --quiet; then
            echo "Build output unchanged, nothing to commit."
            exit 0
          fi
          
          SUBMODULE_SHA=$(git -C micropython rev-parse --short HEAD)
          git commit -m "chore: rebuild micropython wasm (submodule @ ${SUBMODULE_SHA}) [skip ci]"
          git push