name: Docker

on:
  pull_request:
    paths:
      - 'VERSION'
      - 'Dockerfile'
      - '.dockerignore'
      - 'src/**'
      - 'web/**'
      - 'Cargo.toml'
      - 'Cargo.lock'
      - 'migrations/**'
      - 'build.rs'
      - '.github/workflows/docker.yml'
  workflow_dispatch:

concurrency:
  group: docker-${{ github.ref }}
  cancel-in-progress: true

permissions:
  contents: read
  packages: write

jobs:
  docker:
    runs-on: ubuntu-latest
    timeout-minutes: 90
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          fetch-depth: 1

      - name: Lowercase image name
        id: image
        run: |
          echo "name=$(echo 'ghcr.io/bybrooklyn/alchemist' \
            | tr '[:upper:]' '[:lower:]')" >> "$GITHUB_OUTPUT"

      - name: Set up QEMU
        if: github.event_name == 'workflow_dispatch'
        uses: docker/setup-qemu-action@v3

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

      - name: Log in to GHCR
        if: github.event_name != 'pull_request'
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build (PR preview — no push)
        if: github.event_name == 'pull_request'
        uses: docker/build-push-action@v6
        with:
          context: .
          platforms: linux/amd64
          push: false
          cache-from: |
            type=gha,scope=docker-amd64
            type=registry,ref=ghcr.io/bybrooklyn/alchemist:buildcache-amd64
          cache-to: |
            type=gha,scope=docker-amd64,mode=max
          provenance: false

      - name: Build and push (manual dispatch)
        if: github.event_name == 'workflow_dispatch'
        uses: docker/build-push-action@v6
        with:
          context: .
          platforms: linux/amd64,linux/arm64
          push: true
          tags: ${{ steps.image.outputs.name }}:dev
          cache-from: |
            type=gha,scope=docker-amd64
            type=gha,scope=docker-arm64
            type=registry,ref=ghcr.io/bybrooklyn/alchemist:buildcache-amd64
            type=registry,ref=ghcr.io/bybrooklyn/alchemist:buildcache-arm64
          cache-to: |
            type=gha,scope=docker-amd64,mode=max
            type=gha,scope=docker-arm64,mode=max
            type=registry,ref=ghcr.io/bybrooklyn/alchemist:buildcache-amd64,mode=max,image-manifest=true,oci-mediatypes=true
            type=registry,ref=ghcr.io/bybrooklyn/alchemist:buildcache-arm64,mode=max,image-manifest=true,oci-mediatypes=true
          provenance: false