name: Release multi-arch container image

on:
  workflow_dispatch:
  push:
    branches:
      - main
      - "test/**"
  schedule:
    - cron: "0 0 * * *" # Run every day at 00:00 UTC.

env:
  REGISTRY: ghcr.io/${{ github.repository_owner }}
  REGISTRY_USER: ${{ github.actor }}
  REGISTRY_PASSWORD: ${{ github.token }}
  IMAGE_NAME: dangerzone/dangerzone
  BUILDKIT_IMAGE: "docker.io/moby/buildkit:v19.0@sha256:14aa1b4dd92ea0a4cd03a54d0c6079046ea98cd0c0ae6176bdd7036ba370cbbe"

jobs:
  lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Install dev. dependencies
        run: |-
          sudo apt-get update
          sudo apt-get install -y git python3-poetry --no-install-recommends
          poetry install --only package

      - name: Verify that the Dockerfile matches the commited template and params
        run: |-
          cp Dockerfile Dockerfile.orig
          make Dockerfile
          diff Dockerfile.orig Dockerfile

  prepare:
    runs-on: ubuntu-latest
    outputs:
      debian_archive_date: ${{ steps.date.outputs.debian_archive_date }}
      source_date_epoch: ${{ steps.date.outputs.source_date_epoch }}
    steps:
      - name: Get current date
        id: date
        run: |
          DEBIAN_ARCHIVE_DATE=$(date -u +'%Y%m%d')
          SOURCE_DATE_EPOCH=$(date -u -d ${DEBIAN_ARCHIVE_DATE} +"%s")
          echo "debian_archive_date=${DEBIAN_ARCHIVE_DATE}" >> $GITHUB_OUTPUT
          echo "source_date_epoch=${SOURCE_DATE_EPOCH}" >> $GITHUB_OUTPUT

  build:
    runs-on: ubuntu-24.04${{ matrix.platform.suffix }}
    needs:
      - prepare
    strategy:
      fail-fast: false
      matrix:
        platform:
          - suffix: ""
            name: "linux/amd64"
          - suffix: "-arm"
            name: "linux/arm64"
    steps:
      - uses: actions/checkout@v4

      - name: Prepare
        run: |
          platform=${{ matrix.platform.name }}
          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV

      - name: Login to GHCR
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.repository_owner }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
        with:
          driver-opts: image=${{ env.BUILDKIT_IMAGE }}

      - name: Build and push by digest
        id: build
        uses: docker/build-push-action@v6
        with:
          context: ./dangerzone/
          file: Dockerfile
          build-args: |
            DEBIAN_ARCHIVE_DATE=${{ needs.prepare.outputs.debian_archive_date }}
            SOURCE_DATE_EPOCH=${{ needs.prepare.outputs.source_date_epoch }}
          # Remove potentially incorrect Docker provenance that cannot be
          # reproduced.
          provenance: false
          platforms: ${{ matrix.platform.name }}
          outputs: type=image,"name=${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}",rewrite-timestamp=true,push-by-digest=true,name-canonical=true,push=true
          cache-from: type=gha
          cache-to: type=gha,mode=max

      - name: Export digest
        run: |
          mkdir -p ${{ runner.temp }}/digests
          digest="${{ steps.build.outputs.digest }}"
          touch "${{ runner.temp }}/digests/${digest#sha256:}"
          echo "Image digest is: ${digest}"

      - name: Upload digest
        uses: actions/upload-artifact@v4
        with:
          name: digests-${{ env.PLATFORM_PAIR }}
          path: ${{ runner.temp }}/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    runs-on: ubuntu-latest
    needs:
      - prepare
      - build
    outputs:
      digest: ${{ steps.image.outputs.digest }}
      image: ${{ steps.image.outputs.image }}
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Compute image tag
        id: tag
        run: |
          DEBIAN_ARCHIVE_DATE=${{ needs.prepare.outputs.debian_archive_date }}
          TAG=$(git describe --long --first-parent | tail -c +2)
          echo "tag=${DEBIAN_ARCHIVE_DATE}-${TAG}" >> $GITHUB_OUTPUT

      - name: Download digests
        uses: actions/download-artifact@v4
        with:
          path: ${{ runner.temp }}/digests
          pattern: digests-*
          merge-multiple: true

      - name: Login to GHCR
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.repository_owner }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
        with:
          driver-opts: image=${{ env.BUILDKIT_IMAGE }}

      - name: Create manifest list and push
        working-directory: ${{ runner.temp }}/digests
        run: |
          IMAGE=${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ steps.tag.outputs.tag }}
          DIGESTS=$(printf '${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}@sha256:%s ' *)
          docker buildx imagetools create -t ${IMAGE} ${DIGESTS}

      - name: Inspect image
        id: image
        run: |
          # NOTE: Set the image as an output because the `env` context is not
          # available to the inputs of a reusable workflow call.
          image_name="${REGISTRY}/${IMAGE_NAME}"
          echo "image=$image_name" >> "$GITHUB_OUTPUT"
          docker buildx imagetools inspect ${image_name}:${{ steps.tag.outputs.tag }}
          digest=$(docker buildx imagetools inspect ${image_name}:${{ steps.tag.outputs.tag }} --format "{{json .Manifest}}" | jq -r '.digest')
          echo "digest=$digest" >> "$GITHUB_OUTPUT"

  # This step calls the container workflow to generate provenance and push it to
  # the container registry.
  provenance:
    needs:
      - merge
    permissions:
      actions: read # for detecting the Github Actions environment.
      id-token: write # for creating OIDC tokens for signing.
      packages: write # for uploading attestations.
    uses: slsa-framework/slsa-github-generator/.github/workflows/generator_container_slsa3.yml@v2.0.0
    with:
      digest: ${{ needs.merge.outputs.digest }}
      image: ${{ needs.merge.outputs.image }}
      registry-username: ${{ github.actor }}
    secrets:
      registry-password: ${{ secrets.GITHUB_TOKEN }}

  # This step ensures that the image is reproducible
  check-reproducibility:
    needs:
      - prepare
      - merge
    runs-on: ubuntu-24.04${{ matrix.platform.suffix }}
    strategy:
      fail-fast: false
      matrix:
        platform:
          - suffix: ""
            name: "linux/amd64"
          - suffix: "-arm"
            name: "linux/arm64"
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Reproduce the same container image
        run: |
          ./dev_scripts/reproduce-image.py \
            --debian-archive-date ${{ needs.build.prepare.debian_archive_date }} \
            --source ${{ needs.merge.outputs.image }}@${{ needs.merge.outputs.digest }} \
            --platform ${{ matrix.platform.name }}