name: Docker Build and Push

on:
  push:
    branches:
      - main
      - '*'
    tags:
      - 'v*.*.*'
  pull_request:
    branches:
      - main

env:
  REGISTRY: ghcr.io
  IMAGE_NAME: ${{ github.repository }}

jobs:
  prepare:
    runs-on: ubuntu-latest
    outputs:
      version: ${{ steps.version.outputs.version }}
      tags: ${{ steps.meta.outputs.tags }}
      labels: ${{ steps.meta.outputs.labels }}
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Extract metadata (tags, labels) for Docker
        id: meta
        uses: docker/metadata-action@v6
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=ref,event=branch
            type=ref,event=pr
            type=semver,pattern=v{{version}}
            type=semver,pattern=v{{major}}.{{minor}}
            type=semver,pattern=v{{major}}
            type=semver,pattern={{version}}
            type=semver,pattern={{major}}.{{minor}}
            type=semver,pattern={{major}}
            type=raw,value=latest,enable={{is_default_branch}}
          flavor: |
            latest=false

      - name: Determine version for build
        id: version
        run: |
          if [[ "${{ github.ref }}" == refs/tags/v* ]]; then
            VERSION="${{ github.ref_name }}"
            VERSION="${VERSION#v}"
          else
            VERSION=$(git describe --always --dirty)
          fi
          echo "version=git-${VERSION}" >> $GITHUB_OUTPUT
          echo "Building with version: git-${VERSION}"

  build:
    needs: prepare
    runs-on: ${{ matrix.runner }}
    permissions:
      contents: read
      packages: write
    strategy:
      fail-fast: false
      matrix:
        include:
          - platform: linux/amd64
            runner: ubuntu-latest
          - platform: linux/arm64
            runner: ubuntu-24.04-arm

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      - name: Log in to GitHub Container Registry
        uses: docker/login-action@v4
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push image digest
        id: build
        uses: docker/build-push-action@v6
        with:
          context: .
          platforms: ${{ matrix.platform }}
          push: ${{ github.event_name != 'pull_request' }}
          labels: ${{ needs.prepare.outputs.labels }}
          build-args: |
            VERSION=${{ needs.prepare.outputs.version }}
          cache-from: type=gha,scope=${{ matrix.platform }}
          cache-to: type=gha,mode=max,scope=${{ matrix.platform }}
          outputs: type=image,name=${{ env.REGISTRY }}/${{ env.IMAGE_NAME }},push-by-digest=true,name-canonical=true,push=${{ github.event_name != 'pull_request' }}

      - name: Export digest
        if: github.event_name != 'pull_request'
        run: |
          mkdir -p /tmp/digests
          digest="${{ steps.build.outputs.digest }}"
          touch "/tmp/digests/${digest#sha256:}"

      - name: Upload digest
        if: github.event_name != 'pull_request'
        uses: actions/upload-artifact@v4
        with:
          name: digests-${{ matrix.runner }}
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    needs: [prepare, build]
    if: github.event_name != 'pull_request'
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
    steps:
      - name: Download digests
        uses: actions/download-artifact@v4
        with:
          path: /tmp/digests
          pattern: digests-*
          merge-multiple: true

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      - name: Log in to GitHub Container Registry
        uses: docker/login-action@v4
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Create and push manifest
        run: |
          TAGS=$(echo "${{ needs.prepare.outputs.tags }}" | tr '\n' ' ')
          TAG_ARGS=""
          for tag in $TAGS; do
            TAG_ARGS="$TAG_ARGS -t $tag"
          done
          docker buildx imagetools create $TAG_ARGS \
            $(printf '${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}@sha256:%s ' *)
        working-directory: /tmp/digests

      - name: Inspect image
        run: |
          docker buildx imagetools inspect ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
        continue-on-error: true