name: Docker Image CI

on:
  workflow_call:
    inputs:
      tag:
        required: true
        type: string
      image_name:
        required: true
        type: string
      target:
        required: true
        type: string
      dockerfile:
        required: false
        type: string
        default: Dockerfile

env:
  REGISTRY: ghcr.io
  MAKE_ARGS: ${{ inputs.target }}=1
  DIGEST_PATH: /tmp/digests/${{ inputs.target }}
  DIGEST_NAME_SUFFIX: ${{ inputs.target }}
  DOCKERFILE: ${{ inputs.dockerfile }}

jobs:
  build:
    strategy:
      fail-fast: false
      matrix:
        include:
          - runner: ubuntu-latest
            platform: linux/amd64
          - runner: ubuntu-24.04-arm
            platform: linux/arm64

    name: Build ${{ matrix.platform }}
    runs-on: ${{ matrix.runner }}

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

    steps:
      - name: Checkout (for tag resolution)
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

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

      - name: Compute VERSION for build
        run: |
          if [ "${GITHUB_REF_TYPE}" = "tag" ]; then
            version="${GITHUB_REF_NAME}"
            cache_variant="release"
          elif [ "${GITHUB_REF_NAME}" = "main" ] || [ "${GITHUB_REF_NAME}" = "compat" ]; then
            git fetch --tags origin main
            version="$(git describe --tags --abbrev=0 origin/main 2>/dev/null || git describe --tags --abbrev=0 main 2>/dev/null || echo v0.0.0)"
            cache_variant="${GITHUB_REF_NAME}"
          else
            version="v$(date -u +'%Y%m%d-%H%M')"
            cache_variant="nightly"
          fi
          echo "VERSION_FOR_BUILD=$version" >> $GITHUB_ENV
          echo "CACHE_VARIANT=$cache_variant" >> $GITHUB_ENV
          if [ "${GITHUB_REF_TYPE}" = "branch" ]; then
            echo "BRANCH_FOR_BUILD=${GITHUB_REF_NAME}" >> $GITHUB_ENV
          else
            echo "BRANCH_FOR_BUILD=" >> $GITHUB_ENV
          fi

      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.REGISTRY }}/${{ inputs.image_name }}
          tags: |
            type=raw,value=${{ inputs.tag }},event=branch
            type=ref,event=tag

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
        with:
          platforms: ${{ matrix.platform }}

      - name: Login to registry
        uses: docker/login-action@v3
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push by digest
        id: build
        uses: docker/build-push-action@v6
        with:
          platforms: ${{ matrix.platform }}
          labels: ${{ steps.meta.outputs.labels }}
          file: ${{ env.DOCKERFILE }}
          outputs: type=image,name=${{ env.REGISTRY }}/${{ inputs.image_name }},push-by-digest=true,name-canonical=true,push=true
          cache-from: |
            type=gha,scope=${{ github.workflow }}-${{ env.CACHE_VARIANT }}-${{ env.PLATFORM_PAIR }}
            type=registry,ref=${{ env.REGISTRY }}/${{ inputs.image_name }}:buildcache-${{ env.CACHE_VARIANT }}-${{ env.PLATFORM_PAIR }}
          cache-to: |
            type=gha,scope=${{ github.workflow }}-${{ env.CACHE_VARIANT }}-${{ env.PLATFORM_PAIR }},mode=max
            type=registry,ref=${{ env.REGISTRY }}/${{ inputs.image_name }}:buildcache-${{ env.CACHE_VARIANT }}-${{ env.PLATFORM_PAIR }},mode=max
          build-args: |
            VERSION=${{ env.VERSION_FOR_BUILD }}
            MAKE_ARGS=${{ env.MAKE_ARGS }}
            BRANCH=${{ env.BRANCH_FOR_BUILD }}

      - name: Generate artifact attestation
        uses: actions/attest-build-provenance@v1
        with:
          subject-name: ${{ env.REGISTRY }}/${{ inputs.image_name }}
          subject-digest: ${{ steps.build.outputs.digest }}
          push-to-registry: true

      - name: Export digest
        run: |
          mkdir -p ${{ env.DIGEST_PATH }}
          digest="${{ steps.build.outputs.digest }}"
          touch "${{ env.DIGEST_PATH }}/${digest#sha256:}"

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

  merge:
    needs: build
    runs-on: ubuntu-latest

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

    steps:
      - name: Download digests
        uses: actions/download-artifact@v4
        with:
          path: ${{ env.DIGEST_PATH }}
          pattern: digests-*-${{ env.DIGEST_NAME_SUFFIX }}
          merge-multiple: true

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

      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.REGISTRY }}/${{ inputs.image_name }}
          tags: |
            type=raw,value=${{ inputs.tag }},event=branch
            type=ref,event=tag

      - name: Login to registry
        uses: docker/login-action@v3
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Create manifest list and push
        id: push
        working-directory: ${{ env.DIGEST_PATH }}
        run: |
          docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
            $(printf '${{ env.REGISTRY }}/${{ inputs.image_name }}@sha256:%s ' *)

      - name: Inspect image
        run: |
          docker buildx imagetools inspect ${{ env.REGISTRY }}/${{ inputs.image_name }}:${{ steps.meta.outputs.version }}