name: Build and Push Docker Images

on:
  push:
    branches: [main]
    paths:
      - 'backend/**'
      - 'frontend/**'
      - '.github/workflows/docker-build.yml'
  pull_request:
    branches: [main]
    paths:
      - 'backend/**'
      - 'frontend/**'
  workflow_dispatch:

env:
  REGISTRY: ghcr.io
  BACKEND_IMAGE: ghcr.io/${{ github.repository_owner }}/priceghost-backend
  FRONTEND_IMAGE: ghcr.io/${{ github.repository_owner }}/priceghost-frontend

jobs:
  # Detect which paths changed
  changes:
    runs-on: ubuntu-latest
    outputs:
      backend: ${{ steps.filter.outputs.backend }}
      frontend: ${{ steps.filter.outputs.frontend }}
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Check for changes
        uses: dorny/paths-filter@v3
        id: filter
        with:
          filters: |
            backend:
              - 'backend/**'
            frontend:
              - 'frontend/**'

  build-backend:
    needs: changes
    if: needs.changes.outputs.backend == 'true' || github.event_name == 'workflow_dispatch'
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write

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

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

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

      - name: Extract metadata for Backend
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.BACKEND_IMAGE }}
          tags: |
            type=ref,event=branch
            type=sha,prefix=
            type=raw,value=latest,enable={{is_default_branch}}

      - name: Build and push Backend image
        uses: docker/build-push-action@v5
        with:
          context: ./backend
          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

  build-frontend:
    needs: changes
    if: needs.changes.outputs.frontend == 'true' || github.event_name == 'workflow_dispatch'
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write

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

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

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

      - name: Extract metadata for Frontend
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.FRONTEND_IMAGE }}
          tags: |
            type=ref,event=branch
            type=sha,prefix=
            type=raw,value=latest,enable={{is_default_branch}}

      - name: Build and push Frontend image
        uses: docker/build-push-action@v5
        with:
          context: ./frontend
          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