name: Build container image

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

env:
  IMAGE_DESC: "Custom Fedora bootc image"
  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: |
          # Extrahiert den Domain-Host aus der Gitea/GitHub-URL
          REGISTRY_HOST=$(echo "${{ github.server_url }}" | awk -F/ '{print $3}')
          OWNER_LOWER=$(echo "${{ github.repository_owner }}" | tr '[:upper:]' '[:lower:]')
          
          # Extrahiert den Repository-Namen sicher aus github.repository (owner/repo)
          REPO_NAME=$(echo "${{ github.repository }}" | cut -d'/' -f2 | tr '[:upper:]' '[:lower:]')

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

      - name: Determine image tag
        run: |
          BRANCH="${GITHUB_REF_NAME}"
          if [[ "$BRANCH" == "main" ]]; then
            echo "IMAGE_TAG=${DEFAULT_TAG}" >> ${GITHUB_ENV}
            echo "IS_TEST_BUILD=false" >> ${GITHUB_ENV}
          else
            SANITIZED=$(echo "$BRANCH" | sed 's/[^a-zA-Z0-9._-]/-/g' | head -c 50)
            echo "IMAGE_TAG=test-${SANITIZED}" >> ${GITHUB_ENV}
            echo "IS_TEST_BUILD=true" >> ${GITHUB_ENV}
          fi

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

      - name: Image Metadata
        id: metadata
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.IMAGE_REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=raw,value=${{ env.IMAGE_TAG }}
            type=raw,value=${{ env.IMAGE_TAG }}.{{date 'YYYYMMDD'}},enable=${{ env.IS_TEST_BUILD == 'false' }}
            type=raw,value={{date 'YYYYMMDD'}},enable=${{ env.IS_TEST_BUILD == 'false' }}
            type=sha,enable=${{ github.event_name == 'pull_request' }}
            type=ref,event=pr
          labels: |
            org.opencontainers.image.created={{date 'YYYY-MM-DDTHH:mm:ssZ'}}
            org.opencontainers.image.description=${{ 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.IMAGE_TAG }}
            containers.bootc=1
            ostree.bootable=1

      # 1. Image mit Buildah v3 bauen
      - name: Build Image with Buildah
        id: build_image
        uses: redhat-actions/buildah-build@v3
        with:
          image: ${{ env.IMAGE_NAME }}
          tags: ${{ env.IMAGE_TAG }}
          containerfiles: ./Containerfile
          labels: ${{ steps.metadata.outputs.labels }}
          oci: true

      # 2. In lokales OCI-Verzeichnis exportieren
      - name: Export Image to OCI Layout
        run: |
          buildah push ${{ env.IMAGE_NAME }}:${{ env.IMAGE_TAG }} oci:./oci-image

      # 3. Chunkah via Action auf das OCI-Verzeichnis anwenden
      - name: Process OCI Image with Chunkah
        uses: coreos/chunkah-action@main
        with:
          target: ./oci-image

      # 4. Skopeo via Action bereitstellen
      - name: Setup Skopeo
        uses: warjiang/setup-skopeo@v1
        with:
          version: 'latest'

      # 5. Gechunketes Image für ALLE generierten Tags pushen & Digest erfassen
      - name: Push Chunked Image to Registry
        run: |
          echo "${{ secrets.REGISTRY }}" | skopeo login "${{ env.REGISTRY_HOST }}" -u "${{ github.repository_owner }}" --password-stdin
          
          for TAG_REF in ${{ steps.metadata.outputs.tags }}; do
            echo "Pushe gechunketes Image nach: docker://${TAG_REF}"
            skopeo copy \
              --dest-compress-format zstd:chunked \
              --digestfile /tmp/digest.txt \
              oci:./oci-image "docker://${TAG_REF}"
          done
          
          # Exakten Manifest-Digest für Cosign im GITHUB_ENV speichern
          echo "IMAGE_DIGEST=$(cat /tmp/digest.txt)" >> ${GITHUB_ENV}

      # 6. Cosign installieren
      - name: Install Cosign
        if: env.IS_TEST_BUILD == 'false'
        uses: sigstore/cosign-installer@v3

      # 7. Container Image signieren
      - name: Sign container image
        if: env.IS_TEST_BUILD == 'false'
        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 }}@${{ env.IMAGE_DIGEST }}"
          echo "Signiere Manifest via Digest: ${IMAGE_REF}"
          
          cosign sign -y \
            --key env://COSIGN_PRIVATE_KEY \
            --recursive \
            --registry-referrers-mode=legacy \
            "${IMAGE_REF}"

      # 8. Lokalen OCI-Ordner, temp-Dateien und Buildah-Storage aufräumen
      - name: Post-Build Cleanup
        if: always()
        run: |
          echo "Bereinige temporären OCI-Ordner, temporäre Dateien und Buildah-Storage..."
          rm -rf ./oci-image /tmp/digest.txt || true
          buildah rmi --all --force || true