name: rc

# Release-candidate images for stabilization: every push to a release/**
# branch builds and pushes ghcr.io tags :rc (moving) and
# :rc-<version>-<date> (pinned). Final versioned images still come from
# release.yml on tag push.
on:
  push:
    branches: ['release/**']

permissions:
  contents: read

# One build per branch at a time; a newer push supersedes an in-flight one.
concurrency:
  group: rc-${{ github.ref }}
  cancel-in-progress: true

jobs:
  build-docker:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write

    steps:
      - uses: actions/checkout@v4
        with:
          persist-credentials: false

      - name: Derive RC tags
        id: meta
        run: |
          # release/v0.3.0 -> 0.3.0 (tolerate a missing v prefix too)
          version="${GITHUB_REF_NAME#release/}"
          version="${version#v}"
          date="$(date -u +%Y%m%d)"
          {
            echo "tags<<TAGS_EOF"
            echo "ghcr.io/got-feedback/feedback:rc"
            echo "ghcr.io/got-feedback/feedback:rc-${version}-${date}"
            echo "TAGS_EOF"
          } >> "$GITHUB_OUTPUT"

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Log in to GHCR
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push Docker image
        uses: docker/build-push-action@v6
        with:
          context: .
          platforms: linux/amd64,linux/arm64
          push: true
          tags: ${{ steps.meta.outputs.tags }}
          cache-from: type=gha
          cache-to: type=gha,mode=max