name: build-ci-image

on:
  push:
    paths:
      - Dockerfile
      - .dockerignore
      - .gitea/workflows/build-ci-image.yml
  workflow_dispatch:

env:
  REGISTRY_HOST: git.neosisyphus.com
  REGISTRY_IMAGE: git.neosisyphus.com/evol3d/evol-testbed
  # Optional. If this secret is not set, the workflow uses GITHUB_ACTOR.
  REGISTRY_USERNAME: ${{ secrets.REGISTRY_USERNAME }}

jobs:
  image:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v4

      - name: Log in to container registry
        run: |
          set -eu
          username="${REGISTRY_USERNAME:-${GITHUB_ACTOR:-}}"
          if [ -z "$username" ]; then
            echo "REGISTRY_USERNAME secret is empty and GITHUB_ACTOR is not set" >&2
            exit 1
          fi
          if [ -z "${{ secrets.REGISTRY_PASSWORD }}" ]; then
            echo "REGISTRY_PASSWORD secret is empty. Set it to a Gitea access token with package write permission." >&2
            exit 1
          fi
          echo "${{ secrets.REGISTRY_PASSWORD }}" | docker login "$REGISTRY_HOST" \
            -u "$username" \
            --password-stdin

      - name: Build and push CI image
        env:
          DOCKER_BUILDKIT: 1
        run: |
          if docker buildx version >/dev/null 2>&1; then
            docker buildx create --use --name evol-testbed-builder || docker buildx use evol-testbed-builder
            docker buildx build \
              --build-arg BASE_IMAGE=catthehacker/ubuntu:act-latest \
              --build-arg LLVM_VERSION=22 \
              --build-arg MESON_VERSION=latest \
              --cache-from type=registry,ref="$REGISTRY_IMAGE:buildcache" \
              --cache-to type=registry,ref="$REGISTRY_IMAGE:buildcache",mode=max \
              --tag "$REGISTRY_IMAGE:latest" \
              --file Dockerfile \
              --push \
              .
          else
            echo "docker buildx is unavailable; falling back to uncached docker build"
            docker build \
              --build-arg BASE_IMAGE=catthehacker/ubuntu:act-latest \
              --build-arg LLVM_VERSION=22 \
              --build-arg MESON_VERSION=latest \
              --tag "$REGISTRY_IMAGE:latest" \
              --file Dockerfile \
              .
            docker push "$REGISTRY_IMAGE:latest"
          fi