name: Publish Docker Images

on:
  push:
    branches:
      - main
      - develop
    tags:
      - 'v*.*.*'
  pull_request:
    types: [opened, synchronize, reopened]

env:
  DOCKER_REGISTRY: labs.phundrak.com  # Override in repository settings if needed
  IMAGE_NAME: phundrak/phundrak-dot-com-backend

jobs:
  build-and-publish:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write  # Required for pushing to Phundrak Labs registry
      pull-requests: read

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

      - name: Install Nix
        uses: cachix/install-nix-action@v27
        with:
          nix_path: nixpkgs=channel:nixos-unstable

      - name: Setup Cachix
        uses: cachix/cachix-action@v15
        with:
          name: devenv
          authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
          skipPush: true

      - name: Build Docker image with Nix
        run: |
          echo "Building Docker image..."
          nix build .#backendDockerLatest --print-build-logs

      - name: Load Docker image
        run: |
          echo "Loading Docker image into Docker daemon..."
          docker load < result

      - name: Log in to Docker Registry
        run: |
          echo "${{ secrets.DOCKER_PASSWORD }}" | docker login ${{ env.DOCKER_REGISTRY }} -u ${{ secrets.DOCKER_USERNAME }} --password-stdin

      - name: Determine tags and push images
        run: |
          set -euo pipefail

          REGISTRY="${{ env.DOCKER_REGISTRY }}"
          IMAGE_NAME="${{ env.IMAGE_NAME }}"

          # The locally built image from Nix
          LOCAL_IMAGE="localhost/phundrak/backend-rust:latest"

          echo "Event: ${{ github.event_name }}"
          echo "Ref: ${{ github.ref }}"
          echo "Ref type: ${{ github.ref_type }}"

          # Determine which tags to push based on the event
          if [[ "${{ github.event_name }}" == "push" && "${{ github.ref_type }}" == "tag" ]]; then
            # Tag push on main branch → publish 'latest' and versioned tag
            echo "Tag push detected"
            TAG_VERSION="${{ github.ref_name }}"
            # Remove 'v' prefix if present (v1.0.0 → 1.0.0)
            TAG_VERSION="${TAG_VERSION#v}"

            echo "Tagging and pushing: ${REGISTRY}/${IMAGE_NAME}:latest"
            docker tag "${LOCAL_IMAGE}" "${REGISTRY}/${IMAGE_NAME}:latest"
            docker push "${REGISTRY}/${IMAGE_NAME}:latest"

            echo "Tagging and pushing: ${REGISTRY}/${IMAGE_NAME}:${TAG_VERSION}"
            docker tag "${LOCAL_IMAGE}" "${REGISTRY}/${IMAGE_NAME}:${TAG_VERSION}"
            docker push "${REGISTRY}/${IMAGE_NAME}:${TAG_VERSION}"

          elif [[ "${{ github.event_name }}" == "push" && "${{ github.ref }}" == "refs/heads/develop" ]]; then
            # Push on develop branch → publish 'develop' tag
            echo "Push to develop branch detected"

            echo "Tagging and pushing: ${REGISTRY}/${IMAGE_NAME}:develop"
            docker tag "${LOCAL_IMAGE}" "${REGISTRY}/${IMAGE_NAME}:develop"
            docker push "${REGISTRY}/${IMAGE_NAME}:develop"

          elif [[ "${{ github.event_name }}" == "pull_request" ]]; then
            # Pull request → publish 'pr<number>' tag
            echo "Pull request detected"
            PR_NUMBER="${{ github.event.pull_request.number }}"

            echo "Tagging and pushing: ${REGISTRY}/${IMAGE_NAME}:pr${PR_NUMBER}"
            docker tag "${LOCAL_IMAGE}" "${REGISTRY}/${IMAGE_NAME}:pr${PR_NUMBER}"
            docker push "${REGISTRY}/${IMAGE_NAME}:pr${PR_NUMBER}"

          elif [[ "${{ github.event_name }}" == "push" && "${{ github.ref }}" == "refs/heads/main" ]]; then
            # Push to main branch (not a tag) → publish 'latest'
            echo "Push to main branch detected"

            echo "Tagging and pushing: ${REGISTRY}/${IMAGE_NAME}:latest"
            docker tag "${LOCAL_IMAGE}" "${REGISTRY}/${IMAGE_NAME}:latest"
            docker push "${REGISTRY}/${IMAGE_NAME}:latest"

          else
            echo "Unknown event or ref, skipping push"
            exit 1
          fi

      - name: Log out from Docker Registry
        if: always()
        run: docker logout ${{ env.DOCKER_REGISTRY }}

      - name: Image published successfully
        run: |
          echo "✅ Docker image(s) published successfully to ${{ env.DOCKER_REGISTRY }}/${{ env.IMAGE_NAME }}"