.github/workflows/docker-build.yml

name: Build & Push to GHCR

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]
  workflow_dispatch:
    inputs:
      tag:
        description: 'Image tag (default: latest)'
        required: false
        default: 'latest'

env:
  REGISTRY: ghcr.io
  IMAGE_NAME: ${{ github.repository }}

jobs:
  build-push:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write

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

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

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

      - name: Extract metadata
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=raw,value=latest,enable={{is_default_branch}}
            type=raw,value=${{ github.event.inputs.tag || 'latest' }},enable=${{ github.event_name == 'workflow_dispatch' }}
            type=sha,prefix=sha-

      - name: Build and push
        id: build-push
        uses: docker/build-push-action@v5
        with:
          context: .
          push: ${{ github.event_name != 'pull_request' }}
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          cache-from: type=gha
          cache-to: type=gha,mode=max
          platforms: linux/amd64

      - name: Output image digest
        run: echo "Digest ${{ steps.build-push.outputs.digest }}"