# ref: https://docs.docker.com/ci-cd/github-actions/
# https://blog.oddbit.com/post/2020-09-25-building-multi-architecture-im/

name: docker

on: 
  push:
    branches:
    - master
    tags:
    - 'v*'

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
    - name: Prepare
      id: prepare
      run: |
        DOCKER_IMAGE=${{ secrets.DOCKER_IMAGE }}
        VERSION=latest

        # If this is git tag, use the tag name as a docker tag
        if [[ $GITHUB_REF == refs/tags/* ]]; then
          VERSION=${GITHUB_REF#refs/tags/v}
        fi
        TAGS="${DOCKER_IMAGE}:${VERSION}"

        # If the VERSION looks like a version number, assume that
        # this is the most recent version of the image and also
        # tag it 'latest'.
        if [[ $VERSION =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]]; then
          MAJOR_VERSION=`echo $VERSION | awk '{split($0,a,"."); print a[1]}'`
          MINOR_VERSION=`echo $VERSION | awk '{split($0,a,"."); print a[2]}'`
          TAGS="$TAGS,${DOCKER_IMAGE}:${MAJOR_VERSION},${DOCKER_IMAGE}:${MAJOR_VERSION}.${MINOR_VERSION},${DOCKER_IMAGE}:latest"
        fi

        # Set output parameters.
        echo "tags=${TAGS}" >> $GITHUB_OUTPUT
        echo "docker_image=${DOCKER_IMAGE}" >> $GITHUB_OUTPUT
        echo "docker_platforms=linux/386,linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64/v8,linux/s390x,linux/riscv64" >> $GITHUB_OUTPUT

    - name: Set up QEMU
      uses: docker/setup-qemu-action@v3

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

    - name: Environment
      run: |
        echo home=$HOME
        echo git_ref=$GITHUB_REF
        echo git_sha=$GITHUB_SHA
        echo image=${{ steps.prepare.outputs.docker_image }}
        echo tags=${{ steps.prepare.outputs.tags }}
        echo platforms=${{ steps.prepare.outputs.docker_platforms }}
        echo avail_platforms=${{ steps.buildx.outputs.platforms }}

    - name: Login to DockerHub
      if: github.event_name != 'pull_request'
      uses: docker/login-action@v3
      with:
        username: ${{ secrets.DOCKER_USERNAME }}
        password: ${{ secrets.DOCKER_PASSWORD }}

    - name: Buildx and push
      uses: docker/build-push-action@v6
      with:
        platforms: ${{ steps.prepare.outputs.docker_platforms }}
        push: true
        tags: ${{ steps.prepare.outputs.tags }}