name: Build container image

on:
  pull_request:
    branches:
      - main
  schedule:
    - cron: '05 12 * * 2,5'
  workflow_dispatch:

env:
  IMAGE_DESC: "Custom Fedora bootc image"
  IMAGE_NAME: "${{ github.event.repository.name }}"
  DEFAULT_TAG: "stable"

concurrency:
  group: ${{ github.workflow }}-${{ github.ref || github.run_id }}
  cancel-in-progress: true

jobs:
  build_push:
    name: Build and push image
    runs-on: ubuntu-24.04

    permissions:
      contents: read
      packages: write
      id-token: write

    steps:
      - name: Prepare environment
        run: |
          REGISTRY_HOST=$(echo "${{ github.server_url }}" | awk -F/ '{print $3}')
          OWNER_LOWER="${{ github.repository_owner }}"
          NAME_LOWER="${{ env.IMAGE_NAME }}"

          echo "REGISTRY_HOST=${REGISTRY_HOST}" >> ${GITHUB_ENV}
          echo "IMAGE_REGISTRY=${REGISTRY_HOST}/${OWNER_LOWER,,}" >> ${GITHUB_ENV}
          echo "IMAGE_NAME=${NAME_LOWER,,}" >> ${GITHUB_ENV}

          # Aktuelles Tagesdatum direkt von der Runner-VM beziehen (UTC)
          echo "DATE_TAG=$(date -u +'%Y%m%d')" >> ${GITHUB_ENV}
          echo "BUILD_DATE_ISO=$(date -u +'%Y-%m-%dT%H:%M:%SZ')" >> ${GITHUB_ENV}

      - name: Checkout
        uses: actions/checkout@v7.0.1

      # Generiert die auth.json dynamisch im configs/ Ordner aus Template & Secret
      - name: Prepare Registry Auth File
        env:
          AUTH_BASE64: ${{ secrets.READONLY_AUTH_BASE64 }}
        run: |
          sed "s|READONLY_TOKEN_PLACEHOLDER|${AUTH_BASE64}|g" configs/auth.json.template > configs/auth.json

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4.3.0

      - name: Image Metadata
        id: metadata
        uses: docker/metadata-action@v6.2.0
        with:
          images: ${{ env.IMAGE_REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=raw,value=${{ env.DEFAULT_TAG }},enable=${{ github.ref_name == 'main' }}
            type=raw,value=${{ env.DEFAULT_TAG }}.${{ env.DATE_TAG }},enable=${{ github.ref_name == 'main' }}
            type=raw,value=${{ env.DATE_TAG }},enable=${{ github.ref_name == 'main' }}
            type=raw,value=test-{{branch}},enable=${{ github.ref_name != 'main' && github.event_name != 'pull_request' }}
            type=ref,event=pr,prefix=test-pr-
          labels: |
            org.opencontainers.image.created=${{ env.BUILD_DATE_ISO }}
            org.opencontainers.image.description=${{ env.IMAGE_DESC }}
            org.opencontainers.image.documentation=${{ github.server_url }}/${{ github.repository }}
            org.opencontainers.image.source=${{ github.server_url }}/${{ github.repository }}
            org.opencontainers.image.title=${{ env.IMAGE_NAME }}
            org.opencontainers.image.url=${{ github.server_url }}/${{ github.repository }}
            org.opencontainers.image.vendor=${{ github.repository_owner }}
            org.opencontainers.image.version=${{ env.DEFAULT_TAG }}.${{ env.DATE_TAG }}
            containers.bootc=1
            ostree.bootable=1

      - name: Login to Gitea Container Registry
        if: github.event_name != 'pull_request'
        uses: docker/login-action@v4.6.0
        with:
          registry: ${{ env.REGISTRY_HOST }}
          username: ${{ github.repository_owner }}
          password: ${{ secrets.REGISTRY }}

      - name: Build and Push Image (Docker Buildx)
        uses: docker/build-push-action@v7.3.0
        id: build_image
        with:
          context: .
          file: ./Containerfile
          push: ${{ github.event_name != 'pull_request' }}
          tags: ${{ steps.metadata.outputs.tags }}
          labels: ${{ steps.metadata.outputs.labels }}
          oci-mediatypes: true
          compression: zstd
          # Aktiviert die Chunk-Map für zstd:chunked Range-Requests
          build-args: |
            BUILDKIT_OCI_MEDIATYPE=true
          output: type=registry,push=${{ github.event_name != 'pull_request' }},oci-mediatypes=true,compression=zstd,compression-args=binary-path=/usr/bin/go-zstd-chunked

      - name: Install envsubst dependencies
        if: github.event_name != 'pull_request' && github.ref_name == 'main'
        run: |
          sudo apt-get update && sudo apt-get install -y gettext

      - name: Install Cosign
        if: github.event_name != 'pull_request' && github.ref_name == 'main'
        uses: sigstore/cosign-installer@v4.1.2

      - name: Sign container image
        if: github.event_name != 'pull_request' && github.ref_name == 'main'
        env:
          COSIGN_PRIVATE_KEY: ${{ secrets.SIGNING_SECRET }}
          COSIGN_PASSWORD: ""
        run: |
          echo "${{ secrets.REGISTRY }}" | cosign login "${{ env.REGISTRY_HOST }}" -u "${{ github.repository_owner }}" --password-stdin

          IMAGE_REF="${{ env.IMAGE_REGISTRY }}/${{ env.IMAGE_NAME }}@${{ steps.build_image.outputs.digest }}"
          echo "Signiere Manifest via Direct Digest: ${IMAGE_REF}"

          cosign sign -y \
            --key env://COSIGN_PRIVATE_KEY \
            --recursive \
            --use-signing-config=false \
            --new-bundle-format=false \
            --registry-referrers-mode=legacy \
            "${IMAGE_REF}"

      - name: Post-Build Cleanup
        if: always()
        run: |
          echo "Lösche erzeugte Auth-Datei..."
          rm -f configs/auth.json
          echo "Leere Buildx-internen Cache..."
          docker buildx prune -a -f || true