name: Build Cross-Compiled ROS 2 Images

permissions:
  contents: read
  packages: write

on:
  workflow_dispatch:
    inputs:
      platform:
        description: "Target platform"
        required: true
        type: choice
        options: [rk3588]
        default: rk3588
      ros_distro:
        description: "ROS 2 distribution"
        required: true
        type: choice
        options: [rolling, jazzy, lyrical]
        default: lyrical
      push_images:
        description: "Push built images to registry"
        required: false
        type: boolean
        default: false

env:
  REGISTRY: ghcr.io

jobs:
  build:
    runs-on: ubuntu-22.04
    strategy:
      matrix:
        platform: ${{ fromJSON(format('["{0}"]', inputs.platform)) }}
        ros_distro: ${{ fromJSON(format('["{0}"]', inputs.ros_distro)) }}
      fail-fast: false

    steps:
      - name: Set image namespace and tag
        run: |
          echo "IMAGE_NAMESPACE=${GITHUB_REPOSITORY,,}" >> $GITHUB_ENV
          echo "IMAGE_TAG=$(date +%Y%m%d)" >> $GITHUB_ENV

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

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

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

      # ── Compute cache keys ────────────────────────────────────────────
      # Each key = hash(own files) + upstream key, so any upstream change
      # transitively invalidates all downstream stages.
      - name: Compute cache keys
        id: keys
        run: |
          CC_BASE_KEY=$(sha256sum cross_compile/cc_base.Dockerfile | cut -d' ' -f1)

          CC_TOOLCHAIN_FILES=$(find cross_compile/${{ matrix.platform }} -type f | sort | xargs sha256sum | sha256sum | cut -d' ' -f1)
          CC_TOOLCHAIN_KEY=$(echo "$CC_TOOLCHAIN_FILES $CC_BASE_KEY" | sha256sum | cut -d' ' -f1)

          VENDOR_FILES=$(find cross_compile/vendor_packages -type f | sort | xargs sha256sum | sha256sum | cut -d' ' -f1)
          VENDOR_KEY=$(echo "$VENDOR_FILES $CC_TOOLCHAIN_KEY" | sha256sum | cut -d' ' -f1)

          ROS2_FILES=$(find cross_compile/ros2/${{ matrix.ros_distro }} cross_compile/ros2/ros_cpp -type f | sort | xargs sha256sum | sha256sum | cut -d' ' -f1)
          ROS2_KEY=$(echo "$ROS2_FILES $VENDOR_KEY" | sha256sum | cut -d' ' -f1)

          echo "cc_base=$CC_BASE_KEY" >> $GITHUB_OUTPUT
          echo "cc_toolchain=$CC_TOOLCHAIN_KEY" >> $GITHUB_OUTPUT
          echo "vendor=$VENDOR_KEY" >> $GITHUB_OUTPUT
          echo "ros2=$ROS2_KEY" >> $GITHUB_OUTPUT

      # ── Stage 1: cc-base ─────────────────────────────────────────────
      - name: Check cc-base cache
        id: cc-base
        run: |
          EXPECTED="${{ steps.keys.outputs.cc_base }}"
          if docker pull ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/cc-base:latest 2>/dev/null; then
            docker tag ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/cc-base:latest cc-base:latest
            CACHED=$(docker inspect cc-base:latest --format '{{ index .Config.Labels "cache.key" }}' 2>/dev/null || echo "")
            [ "$CACHED" = "$EXPECTED" ] && echo "hit=true" >> $GITHUB_OUTPUT || echo "hit=false" >> $GITHUB_OUTPUT
          else
            echo "hit=false" >> $GITHUB_OUTPUT
          fi

      - name: Build cc-base
        if: steps.cc-base.outputs.hit != 'true'
        run: |
          docker compose -f cross_compile/compose.yaml build cc-base
          TMPDIR=$(mktemp -d)
          docker build \
            --label "cache.key=${{ steps.keys.outputs.cc_base }}" \
            -t cc-base:latest -f - "$TMPDIR" << 'EOF'
          FROM cc-base:latest
          EOF
          rm -rf "$TMPDIR"

      - name: Push cc-base
        if: inputs.push_images
        run: |
          docker tag cc-base:latest \
            ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/cc-base:${{ env.IMAGE_TAG }}
          docker push ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/cc-base:${{ env.IMAGE_TAG }}
          docker tag cc-base:latest \
            ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/cc-base:latest
          docker push ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/cc-base:latest

      # ── Stage 2: cc-toolchain ─────────────────────────────────────────
      - name: Check cc-toolchain cache
        id: cc-toolchain
        run: |
          EXPECTED="${{ steps.keys.outputs.cc_toolchain }}"
          REMOTE="${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-toolchain:latest"
          LOCAL="${{ matrix.platform }}/cc-toolchain:latest"
          if docker pull "$REMOTE" 2>/dev/null; then
            docker tag "$REMOTE" "$LOCAL"
            CACHED=$(docker inspect "$LOCAL" --format '{{ index .Config.Labels "cache.key" }}' 2>/dev/null || echo "")
            [ "$CACHED" = "$EXPECTED" ] && echo "hit=true" >> $GITHUB_OUTPUT || echo "hit=false" >> $GITHUB_OUTPUT
          else
            echo "hit=false" >> $GITHUB_OUTPUT
          fi

      - name: Build cc-toolchain (${{ matrix.platform }})
        if: steps.cc-toolchain.outputs.hit != 'true'
        run: |
          PLATFORM=${{ matrix.platform }} docker compose -f cross_compile/compose.yaml build cc-toolchain
          TMPDIR=$(mktemp -d)
          docker build \
            --label "cache.key=${{ steps.keys.outputs.cc_toolchain }}" \
            -t ${{ matrix.platform }}/cc-toolchain:latest -f - "$TMPDIR" << 'EOF'
          FROM ${{ matrix.platform }}/cc-toolchain:latest
          EOF
          rm -rf "$TMPDIR"

      - name: Push cc-toolchain
        if: inputs.push_images
        run: |
          docker tag ${{ matrix.platform }}/cc-toolchain:latest \
            ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-toolchain:${{ env.IMAGE_TAG }}
          docker push ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-toolchain:${{ env.IMAGE_TAG }}
          docker tag ${{ matrix.platform }}/cc-toolchain:latest \
            ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-toolchain:latest
          docker push ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-toolchain:latest

      # ── Stage 3: vendor-packages ──────────────────────────────────────
      - name: Check vendor-packages cache
        id: vendor
        run: |
          EXPECTED="${{ steps.keys.outputs.vendor }}"
          REMOTE="${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-vendor-packages:latest"
          LOCAL="${{ matrix.platform }}/cc-vendor-packages:latest"
          if docker pull "$REMOTE" 2>/dev/null; then
            docker tag "$REMOTE" "$LOCAL"
            CACHED=$(docker inspect "$LOCAL" --format '{{ index .Config.Labels "cache.key" }}' 2>/dev/null || echo "")
            [ "$CACHED" = "$EXPECTED" ] && echo "hit=true" >> $GITHUB_OUTPUT || echo "hit=false" >> $GITHUB_OUTPUT
          else
            echo "hit=false" >> $GITHUB_OUTPUT
          fi

      - name: Build vendor-packages (${{ matrix.platform }})
        if: steps.vendor.outputs.hit != 'true'
        run: |
          PLATFORM=${{ matrix.platform }} docker compose -f cross_compile/compose.yaml build vendor-packages
          TMPDIR=$(mktemp -d)
          docker build \
            --label "cache.key=${{ steps.keys.outputs.vendor }}" \
            -t ${{ matrix.platform }}/cc-vendor-packages:latest -f - "$TMPDIR" << 'EOF'
          FROM ${{ matrix.platform }}/cc-vendor-packages:latest
          EOF
          rm -rf "$TMPDIR"

      - name: Push vendor-packages
        if: inputs.push_images
        run: |
          docker tag ${{ matrix.platform }}/cc-vendor-packages:latest \
            ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-vendor-packages:${{ env.IMAGE_TAG }}
          docker push ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-vendor-packages:${{ env.IMAGE_TAG }}
          docker tag ${{ matrix.platform }}/cc-vendor-packages:latest \
            ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-vendor-packages:latest
          docker push ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-vendor-packages:latest

      # ── Stage 4: ros2 ─────────────────────────────────────────────────
      - name: Check ros2 cache
        id: ros2
        run: |
          EXPECTED="${{ steps.keys.outputs.ros2 }}"
          REMOTE="${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-ros-${{ matrix.ros_distro }}:latest"
          LOCAL="${{ matrix.platform }}/cc-ros-${{ matrix.ros_distro }}:latest"
          if docker pull "$REMOTE" 2>/dev/null; then
            docker tag "$REMOTE" "$LOCAL"
            CACHED=$(docker inspect "$LOCAL" --format '{{ index .Config.Labels "cache.key" }}' 2>/dev/null || echo "")
            [ "$CACHED" = "$EXPECTED" ] && echo "hit=true" >> $GITHUB_OUTPUT || echo "hit=false" >> $GITHUB_OUTPUT
          else
            echo "hit=false" >> $GITHUB_OUTPUT
          fi

      - name: Build ROS 2 (${{ matrix.ros_distro }})
        if: steps.ros2.outputs.hit != 'true'
        run: |
          PLATFORM=${{ matrix.platform }} ROS_DISTRO=${{ matrix.ros_distro }} docker compose -f cross_compile/compose.yaml build ros2
          TMPDIR=$(mktemp -d)
          docker build \
            --label "cache.key=${{ steps.keys.outputs.ros2 }}" \
            -t ${{ matrix.platform }}/cc-ros-${{ matrix.ros_distro }}:latest -f - "$TMPDIR" << 'EOF'
          FROM ${{ matrix.platform }}/cc-ros-${{ matrix.ros_distro }}:latest
          EOF
          rm -rf "$TMPDIR"

      - name: Push ROS 2 image
        if: inputs.push_images
        run: |
          docker tag ${{ matrix.platform }}/cc-ros-${{ matrix.ros_distro }}:latest \
            ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-ros-${{ matrix.ros_distro }}:${{ env.IMAGE_TAG }}
          docker push ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-ros-${{ matrix.ros_distro }}:${{ env.IMAGE_TAG }}
          docker tag ${{ matrix.platform }}/cc-ros-${{ matrix.ros_distro }}:latest \
            ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-ros-${{ matrix.ros_distro }}:latest
          docker push ${{ env.REGISTRY }}/${{ env.IMAGE_NAMESPACE }}/${{ matrix.platform }}/cc-ros-${{ matrix.ros_distro }}:latest

      # ── Summary ───────────────────────────────────────────────────────
      - name: Image summary
        if: always()
        run: |
          echo "### Built Images :rocket:" >> $GITHUB_STEP_SUMMARY
          docker images \
            --filter "reference=cc-*" \
            --filter "reference=*/cc-*" \
            --format "| \`{{.Repository}}:{{.Tag}}\` | {{.Size}} |" \
            >> $GITHUB_STEP_SUMMARY