name: Build container image for PR
on:
  pull_request:
    types: [labeled, synchronize, reopened, ready_for_review, opened]

permissions:
  contents: read
  packages: write

jobs:
  compute-suffix:
    runs-on: ubuntu-latest
    # This is only allowed to run if:
    # - the PR branch is in the `mastodon/mastodon` repository
    # - the PR is not a draft
    # - the PR has the "build-image" label
    if: ${{ github.event.pull_request.head.repo.full_name == github.repository && !github.event.pull_request.draft && contains(github.event.pull_request.labels.*.name, 'build-image') }}
    steps:
      # Repository needs to be cloned so `git rev-parse` below works
      - name: Clone repository
        uses: actions/checkout@v3
      - id: version_vars
        run: |
          echo mastodon_version_metadata=pr-${{ github.event.pull_request.number }}-$(git rev-parse --short HEAD) >> $GITHUB_OUTPUT
    outputs:
      metadata: ${{ steps.version_vars.outputs.mastodon_version_metadata }}

  build-image:
    needs: compute-suffix
    uses: ./.github/workflows/build-container-image.yml
    with:
      platforms: linux/amd64,linux/arm64
      use_native_arm64_builder: true
      push_to_images: |
        ghcr.io/mastodon/mastodon
      version_metadata: ${{ needs.compute-suffix.outputs.metadata }}
      flavor: |
        latest=auto
      tags: |
        type=ref,event=pr
    secrets: inherit