name: Build Image Template

on:
  workflow_call:
    inputs:
      python_version:
        required: true
        type: string
      dockerfile_path:
        required: true
        type: string
      tag_suffix:
        required: true
        type: string
      image_name:
        required: false
        type: string
        default: fastvideo-dev
      build_args:
        required: false
        type: string
        default: ''
      include_latest_tags:
        required: false
        type: boolean
        default: true
      mark_as_latest:
        required: false
        type: boolean
        default: false
      runner:
        required: false
        type: string
        default: ubuntu-latest
      architecture:
        required: false
        type: string
        default: amd64
      push_by_digest:
        required: false
        type: boolean
        default: false
      digest_artifact_name:
        required: false
        type: string
        default: ''

jobs:
  build-and-push:
    runs-on: ${{ inputs.runner }}
    permissions:
      contents: read
      packages: write
    
    steps:
      - name: Checkout code
        uses: actions/checkout@v4
        # The Docker context intentionally includes .git so the kernel build can
        # initialize its pinned submodules. Do not copy the checkout token with it.
        with:
          persist-credentials: false
      
      - name: Free up disk space
        run: |
          # Display initial space
          echo "Initial disk space:"
          df -h
          
          # Remove large directories directly
          sudo rm -rf /usr/share/dotnet
          sudo rm -rf /usr/local/lib/android
          sudo rm -rf /opt/ghc
          sudo rm -rf /usr/local/share/boost
          sudo rm -rf /usr/share/swift
          sudo rm -rf /usr/local/lib/node_modules
          sudo rm -rf /usr/local/share/powershell
          sudo rm -rf /usr/share/rust
          sudo rm -rf /usr/local/.ghcup
          
          # Remove cached files
          sudo rm -rf /var/lib/apt/lists/*
          sudo rm -rf /var/cache/apt/archives/*
          
          # Clean Docker
          docker system prune -af --volumes
          
          # Display available space after cleanup
          echo "Disk space after cleanup:"
          df -h
      
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
      
      - name: Login to GitHub Container Registry
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.repository_owner }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Normalize image reference
        id: image
        env:
          IMAGE: ghcr.io/${{ github.repository }}/${{ inputs.image_name }}
        run: echo "name=${IMAGE,,}" >> "${GITHUB_OUTPUT}"
      
      - name: Prepare tags
        id: prepare-tags
        run: |
          SHORT_SHA=$(echo ${{ github.sha }} | cut -c1-7)
          
          TAGS="type=raw,value=${{ inputs.tag_suffix }}-sha-${SHORT_SHA}"

          if [[ "${{ inputs.include_latest_tags }}" == "true" ]]; then
            TAGS="type=raw,value=${{ inputs.tag_suffix }}-latest\n${TAGS}"
          fi

          # Tag the designated default variant as the global `latest` image
          if [[ "${{ inputs.include_latest_tags }}" == "true" && "${{ inputs.mark_as_latest }}" == "true" ]]; then
            TAGS="${TAGS}\ntype=raw,value=latest"
          fi
          
          {
            echo "tags<<EOF"
            echo -e "$TAGS"
            echo "EOF" 
          } >> $GITHUB_OUTPUT
      
      - name: Extract metadata for Docker
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ steps.image.outputs.name }}
          tags: ${{ steps.prepare-tags.outputs.tags }}
      
      - name: Build and push Docker image
        if: ${{ !inputs.push_by_digest }}
        id: build-push
        uses: docker/build-push-action@v6
        with:
          context: .
          file: ${{ inputs.dockerfile_path }}
          platforms: linux/${{ inputs.architecture }}
          push: true
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          build-args: ${{ inputs.build_args }}
          cache-from: type=gha,scope=${{ inputs.image_name }}-${{ inputs.tag_suffix }}-${{ inputs.architecture }}
          cache-to: type=gha,mode=max,scope=${{ inputs.image_name }}-${{ inputs.tag_suffix }}-${{ inputs.architecture }}

      # Multi-architecture callers publish immutable manifests by digest here,
      # then create the shared user-facing tags in a single downstream job.
      # This prevents architecture jobs from racing to replace the same tag.
      - name: Build and push Docker image by digest
        if: ${{ inputs.push_by_digest }}
        id: build-push-digest
        uses: docker/build-push-action@v6
        with:
          context: .
          file: ${{ inputs.dockerfile_path }}
          platforms: linux/${{ inputs.architecture }}
          labels: ${{ steps.meta.outputs.labels }}
          build-args: ${{ inputs.build_args }}
          outputs: type=image,name=${{ steps.image.outputs.name }},push-by-digest=true,name-canonical=true,push=true
          cache-from: type=gha,scope=${{ inputs.image_name }}-${{ inputs.tag_suffix }}-${{ inputs.architecture }}
          cache-to: type=gha,mode=max,scope=${{ inputs.image_name }}-${{ inputs.tag_suffix }}-${{ inputs.architecture }}

      - name: Export digest
        if: ${{ inputs.push_by_digest }}
        env:
          DIGEST: ${{ steps.build-push-digest.outputs.digest }}
        run: |
          if [[ -z "${{ inputs.digest_artifact_name }}" ]]; then
            echo "digest_artifact_name is required when push_by_digest is true" >&2
            exit 1
          fi
          mkdir -p /tmp/digests
          touch "/tmp/digests/${DIGEST#sha256:}"

      - name: Upload digest
        if: ${{ inputs.push_by_digest }}
        uses: actions/upload-artifact@v4
        with:
          name: ${{ inputs.digest_artifact_name }}
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1
      
      - name: Success message
        if: ${{ !inputs.push_by_digest }}
        run: |
          echo "✅ Python ${{ inputs.python_version }} image successfully built and pushed to ${{ steps.image.outputs.name }}:${{ inputs.tag_suffix }}-sha-${GITHUB_SHA::7}"
          echo "To run tests with this image, manually trigger the 'Run Tests' workflow."

      - name: Digest success message
        if: ${{ inputs.push_by_digest }}
        env:
          DIGEST: ${{ steps.build-push-digest.outputs.digest }}
        run: |
          echo "✅ Python ${{ inputs.python_version }} linux/${{ inputs.architecture }} image pushed as ${DIGEST}"