name: CI/CD

on:
  push:
    branches: [master]
  pull_request:
    branches: [master]

env:
  BACKEND_IMAGE: ${{ secrets.DOCKERHUB_USERNAME }}/trekr-backend
  FRONTEND_IMAGE: ${{ secrets.DOCKERHUB_USERNAME }}/trekr-frontend

jobs:
  # ── CI: build both images on every push / PR ──────────────────────────────
  build:
    name: Build
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

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

      - name: Build backend image (no push)
        uses: docker/build-push-action@v5
        with:
          context: ./backend
          push: false
          cache-from: type=gha,scope=backend
          cache-to:   type=gha,scope=backend,mode=max

      - name: Build frontend image (no push)
        uses: docker/build-push-action@v5
        with:
          context: ./frontend
          push: false
          cache-from: type=gha,scope=frontend
          cache-to:   type=gha,scope=frontend,mode=max

  # ── CD part 1: push images to DockerHub (master only) ─────────────────────
  push:
    name: Push to DockerHub
    runs-on: ubuntu-latest
    needs: build
    if: github.ref == 'refs/heads/master' && github.event_name == 'push'
    outputs:
      image_tag: ${{ github.sha }}
    steps:
      - uses: actions/checkout@v4

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

      - name: Log in to DockerHub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

      - name: Build and push backend
        uses: docker/build-push-action@v5
        with:
          context: ./backend
          push: true
          tags: |
            ${{ env.BACKEND_IMAGE }}:latest
            ${{ env.BACKEND_IMAGE }}:${{ github.sha }}
          cache-from: type=gha,scope=backend
          cache-to:   type=gha,scope=backend,mode=max

      - name: Build and push frontend
        uses: docker/build-push-action@v5
        with:
          context: ./frontend
          push: true
          tags: |
            ${{ env.FRONTEND_IMAGE }}:latest
            ${{ env.FRONTEND_IMAGE }}:${{ github.sha }}
          cache-from: type=gha,scope=frontend
          cache-to:   type=gha,scope=frontend,mode=max

  # ── CD part 2: deploy to k3s cluster ──────────────────────────────────────
  deploy:
    name: Deploy to Kubernetes
    runs-on: ubuntu-latest
    needs: push
    steps:
      - uses: actions/checkout@v4

      - name: Set up kubectl
        uses: azure/setup-kubectl@v3
        with:
          version: latest

      - name: Configure kubeconfig
        run: |
          echo "${{ secrets.KUBECONFIG_B64 }}" | base64 -d > $HOME/kubeconfig.yaml
          chmod 600 $HOME/kubeconfig.yaml
          echo "KUBECONFIG=$HOME/kubeconfig.yaml" >> $GITHUB_ENV

      - name: Apply namespace
        run: kubectl apply -f k8s/namespace.yaml

      - name: Create / update app secrets
        run: |
          kubectl create secret generic trekr-secrets \
            --namespace=trekr \
            --from-literal=db-password=${{ secrets.DB_PASSWORD }} \
            --from-literal=jwt-secret=${{ secrets.JWT_SECRET }} \
            --save-config \
            --dry-run=client -o yaml | kubectl apply -f -

      - name: Create DB init ConfigMap from DDL
        run: |
          kubectl create configmap trekr-db-init \
            --namespace=trekr \
            --from-file=01-ddl.sql=db-scripts/ddl.sql \
            --save-config \
            --dry-run=client -o yaml | kubectl apply -f -

      - name: Apply Postgres manifests
        run: kubectl apply -f k8s/postgres.yaml

      - name: Wait for Postgres to be ready
        run: kubectl rollout status statefulset/postgres -n trekr --timeout=120s

      - name: Apply backend manifests
        run: kubectl apply -f k8s/backend.yaml

      - name: Apply frontend manifests
        run: kubectl apply -f k8s/frontend.yaml

      - name: Roll out new images
        run: |
          kubectl set image deployment/backend \
            backend=${{ env.BACKEND_IMAGE }}:${{ github.sha }} \
            -n trekr
          kubectl set image deployment/frontend \
            frontend=${{ env.FRONTEND_IMAGE }}:${{ github.sha }} \
            -n trekr

      - name: Wait for rollout to complete
        run: |
          kubectl rollout status deployment/backend  -n trekr --timeout=180s
          kubectl rollout status deployment/frontend -n trekr --timeout=60s

      - name: Print app URL
        run: |
          NODE_IP=$(kubectl get nodes -o jsonpath='{.items[0].status.addresses[?(@.type=="ExternalIP")].address}' 2>/dev/null || \
                    kubectl get nodes -o jsonpath='{.items[0].status.addresses[0].address}')
          echo "App available at: http://${NODE_IP}:30080"