name: Create and publish Docker images

on:
  push:
    tags:
      - 'v*.*.*'
  workflow_dispatch:
    inputs:
      use_latest_tag:
        description: 'Tag as latest instead of branch name'
        required: false
        type: boolean
        default: false

env:
  REGISTRY: ghcr.io

permissions:
  contents: read

jobs:
  prepare:
    runs-on: ubuntu-24.04
    outputs:
      web_image_name: ${{ steps.image-name.outputs.web_image_name }}
      web_legacy_image_name: ${{ steps.image-name.outputs.web_legacy_image_name }}
      compute_worker_image_name: ${{ steps.image-name.outputs.compute_worker_image_name }}
    steps:
      - name: Compute Docker image names
        id: image-name
        run: |
          owner="${GITHUB_REPOSITORY_OWNER,,}"
          echo "web_image_name=${owner}/openreader" >> "$GITHUB_OUTPUT"
          echo "web_legacy_image_name=${owner}/openreader-webui" >> "$GITHUB_OUTPUT"
          echo "compute_worker_image_name=${owner}/openreader-compute-worker" >> "$GITHUB_OUTPUT"

  build:
    needs: prepare
    runs-on: ${{ matrix.runner }}
    permissions:
      actions: write
      contents: read
      packages: write
    strategy:
      fail-fast: false
      matrix:
        include:
          - image_target: web
            arch: amd64
            platform: linux/amd64
            runner: ubuntu-24.04
            context: .
            dockerfile: ./Dockerfile
          - image_target: web
            arch: arm64
            platform: linux/arm64
            runner: ubuntu-24.04-arm
            context: .
            dockerfile: ./Dockerfile
          - image_target: compute-worker
            arch: amd64
            platform: linux/amd64
            runner: ubuntu-24.04
            context: .
            dockerfile: ./packages/compute-worker/Dockerfile
          - image_target: compute-worker
            arch: arm64
            platform: linux/arm64
            runner: ubuntu-24.04-arm
            context: .
            dockerfile: ./packages/compute-worker/Dockerfile

    steps:
      - name: Checkout repository
        uses: actions/checkout@v5
        with:
          ref: ${{ github.sha }}
          fetch-depth: 0

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      - name: Login to GitHub Container Registry
        uses: docker/login-action@v4
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Select image name
        id: image
        run: |
          if [ "${{ matrix.image_target }}" = "web" ]; then
            echo "image_name=${{ needs.prepare.outputs.web_image_name }}" >> "$GITHUB_OUTPUT"
          else
            echo "image_name=${{ needs.prepare.outputs.compute_worker_image_name }}" >> "$GITHUB_OUTPUT"
          fi

      - name: Build and push Docker image (${{ matrix.image_target }} / ${{ matrix.arch }})
        id: build
        uses: docker/build-push-action@v7
        with:
          context: ${{ matrix.context }}
          file: ${{ matrix.dockerfile }}
          platforms: ${{ matrix.platform }}
          cache-from: type=gha,scope=${{ matrix.image_target }}-${{ matrix.arch }}
          cache-to: type=gha,mode=max,scope=${{ matrix.image_target }}-${{ matrix.arch }}
          provenance: false
          outputs: type=image,name=${{ env.REGISTRY }}/${{ steps.image.outputs.image_name }},push-by-digest=true,name-canonical=true,push=true

      - name: Export digest
        run: |
          mkdir -p /tmp/digests/${{ matrix.image_target }}
          digest="${{ steps.build.outputs.digest }}"
          touch "/tmp/digests/${{ matrix.image_target }}/${digest#sha256:}"

      - name: Upload digest
        uses: actions/upload-artifact@v7
        with:
          name: digests-${{ matrix.image_target }}-${{ matrix.arch }}
          path: /tmp/digests/${{ matrix.image_target }}
          if-no-files-found: error
          retention-days: 1

  merge:
    needs: [prepare, build]
    runs-on: ${{ matrix.runner }}
    permissions:
      actions: read
      contents: read
      packages: write
    strategy:
      fail-fast: false
      matrix:
        include:
          - image_target: web
            runner: ubuntu-24.04
          - image_target: compute-worker
            runner: ubuntu-24.04

    steps:
      - name: Download digests
        uses: actions/download-artifact@v8
        with:
          path: /tmp/digests/${{ matrix.image_target }}
          pattern: digests-${{ matrix.image_target }}-*
          merge-multiple: true

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      - name: Login to GitHub Container Registry
        uses: docker/login-action@v4
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Select image names
        id: image
        run: |
          if [ "${{ matrix.image_target }}" = "web" ]; then
            echo "image_name=${{ needs.prepare.outputs.web_image_name }}" >> "$GITHUB_OUTPUT"
            echo "metadata_images<<EOF" >> "$GITHUB_OUTPUT"
            echo "${{ env.REGISTRY }}/${{ needs.prepare.outputs.web_image_name }}" >> "$GITHUB_OUTPUT"
            echo "${{ env.REGISTRY }}/${{ needs.prepare.outputs.web_legacy_image_name }}" >> "$GITHUB_OUTPUT"
            echo "EOF" >> "$GITHUB_OUTPUT"
          else
            echo "image_name=${{ needs.prepare.outputs.compute_worker_image_name }}" >> "$GITHUB_OUTPUT"
            echo "metadata_images=${{ env.REGISTRY }}/${{ needs.prepare.outputs.compute_worker_image_name }}" >> "$GITHUB_OUTPUT"
          fi

      - name: Extract metadata (tags, labels) for Docker
        id: meta
        uses: docker/metadata-action@v6
        with:
          images: ${{ steps.image.outputs.metadata_images }}
          tags: |
            type=raw,value=latest,enable=${{ (github.event_name == 'push' && !contains(github.ref, '-pre')) || (github.event_name == 'workflow_dispatch' && inputs.use_latest_tag == true) }},priority=1000
            type=semver,pattern={{version}}
            type=ref,event=tag
            type=ref,event=branch,enable=${{ github.event_name == 'workflow_dispatch' && inputs.use_latest_tag != true }}

      - name: Create manifest list and push
        working-directory: /tmp/digests/${{ matrix.image_target }}
        run: |
          docker buildx imagetools create \
            $(echo "$TAGS" | xargs -I {} echo -t {}) \
            $(printf '${{ env.REGISTRY }}/${{ steps.image.outputs.image_name }}@sha256:%s ' *)
        env:
          TAGS: ${{ steps.meta.outputs.tags }}

      - name: Output build information
        run: |
          echo "✅ Docker image built and pushed successfully!"
          echo "🐋 Target: ${{ matrix.image_target }}"
          echo "🐋 Images:"
          echo '${{ steps.meta.outputs.tags }}' | sed 's/^/  - /'
          echo "📝 Event: ${{ github.event_name }}"
          if [ "${{ github.event_name }}" == "workflow_dispatch" ]; then
            echo "📝 Triggered by manual workflow dispatch on branch: ${{ github.ref_name }}"
            echo "📝 use_latest_tag: ${{ inputs.use_latest_tag }}"
          else
            echo "📝 Triggered by tag: ${{ github.ref_name }}"
          fi