name: CD Production (Hetzner k3s)

# Production deployment pipeline — Hetzner k3s cluster.
#
# Flow:
#   1. Promote: re-tag preprod → latest + prod-SHA within Scaleway (no rebuild, no data transfer)
#   2. Deploy: kubectl set image + rollout status (blocks until pods are healthy)
#   3. Auto-rollback: kubectl rollout undo if rollout fails
#   4. Smoke tests: belt-and-suspenders HTTP health checks
#   5. Notify Discord
#
# Required secrets:
#   REGISTRY_TOKEN          — Scaleway registry token (read + write)
#   HETZNER_KUBECONFIG      — base64-encoded kubeconfig for xpeditis-prod cluster
#   PROD_BACKEND_URL        — https://api.xpeditis.com (health check)
#   PROD_FRONTEND_URL       — https://app.xpeditis.com (health check)
#   DISCORD_WEBHOOK_URL     — Discord notifications
#
# K8s cluster details (from docs/deployment/hetzner/):
#   Namespace:   xpeditis-prod
#   Deployments: xpeditis-backend (container: backend)
#                xpeditis-frontend (container: frontend)
#
on:
  push:
    branches: [main]

# Only one prod deployment at a time. Never cancel.
concurrency:
  group: cd-production
  cancel-in-progress: false

env:
  REGISTRY: rg.fr-par.scw.cloud/weworkstudio
  IMAGE_BACKEND: rg.fr-par.scw.cloud/weworkstudio/xpeditis-backend
  IMAGE_FRONTEND: rg.fr-par.scw.cloud/weworkstudio/xpeditis-frontend
  K8S_NAMESPACE: xpeditis-prod

jobs:
  # ──────────────────────────────────────────────────────────────
  # 1. Promote preprod → prod tags within Scaleway
  #    imagetools create re-tags at manifest level — no layer
  #    download/upload, instant even for multi-arch images.
  # ──────────────────────────────────────────────────────────────
  promote-images:
    name: Promote Images (preprod → prod)
    runs-on: ubuntu-latest
    outputs:
      short-sha: ${{ steps.sha.outputs.short }}
      backend-image: ${{ steps.images.outputs.backend }}
      frontend-image: ${{ steps.images.outputs.frontend }}

    steps:
      - name: Compute short SHA
        id: sha
        run: echo "short=$(echo ${{ github.sha }} | cut -c1-7)" >> $GITHUB_OUTPUT

      - name: Set image references
        id: images
        run: |
          echo "backend=${{ env.IMAGE_BACKEND }}:prod-${{ steps.sha.outputs.short }}" >> $GITHUB_OUTPUT
          echo "frontend=${{ env.IMAGE_FRONTEND }}:prod-${{ steps.sha.outputs.short }}" >> $GITHUB_OUTPUT

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

      - name: Login to Scaleway Registry
        uses: docker/login-action@v3
        with:
          registry: ${{ env.REGISTRY }}
          username: nologin
          password: ${{ secrets.REGISTRY_TOKEN }}

      - name: Promote Backend (preprod → latest + prod-SHA)
        run: |
          docker buildx imagetools create \
            --tag ${{ env.IMAGE_BACKEND }}:latest \
            --tag ${{ steps.images.outputs.backend }} \
            ${{ env.IMAGE_BACKEND }}:preprod

      - name: Promote Frontend (preprod → latest + prod-SHA)
        run: |
          docker buildx imagetools create \
            --tag ${{ env.IMAGE_FRONTEND }}:latest \
            --tag ${{ steps.images.outputs.frontend }} \
            ${{ env.IMAGE_FRONTEND }}:preprod

      - name: Verify promoted images
        run: |
          echo "=== Backend ==="
          docker buildx imagetools inspect ${{ steps.images.outputs.backend }}
          echo "=== Frontend ==="
          docker buildx imagetools inspect ${{ steps.images.outputs.frontend }}

  # ──────────────────────────────────────────────────────────────
  # 2. Deploy to Hetzner k3s
  #    kubectl set image → rollout status waits for pods to be
  #    healthy (readiness probes pass) before the job succeeds.
  #    Auto-rollback on failure via kubectl rollout undo.
  # ──────────────────────────────────────────────────────────────
  deploy:
    name: Deploy to k3s (xpeditis-prod)
    runs-on: ubuntu-latest
    needs: promote-images
    environment:
      name: production
      url: https://app.xpeditis.com

    steps:
      - name: Configure kubectl
        run: |
          mkdir -p ~/.kube
          echo "${{ secrets.HETZNER_KUBECONFIG }}" | base64 -d > ~/.kube/config
          chmod 600 ~/.kube/config
          kubectl cluster-info
          kubectl get nodes

      - name: Deploy Backend
        run: |
          IMAGE="${{ needs.promote-images.outputs.backend-image }}"
          echo "Deploying backend: $IMAGE"
          kubectl set image deployment/xpeditis-backend \
            backend=$IMAGE \
            -n ${{ env.K8S_NAMESPACE }}
          kubectl rollout status deployment/xpeditis-backend \
            -n ${{ env.K8S_NAMESPACE }} \
            --timeout=300s
          echo "Backend deployed."

      - name: Deploy Frontend
        run: |
          IMAGE="${{ needs.promote-images.outputs.frontend-image }}"
          echo "Deploying frontend: $IMAGE"
          kubectl set image deployment/xpeditis-frontend \
            frontend=$IMAGE \
            -n ${{ env.K8S_NAMESPACE }}
          kubectl rollout status deployment/xpeditis-frontend \
            -n ${{ env.K8S_NAMESPACE }} \
            --timeout=300s
          echo "Frontend deployed."

      - name: Auto-rollback on failure
        if: failure()
        run: |
          echo "Deployment failed — rolling back..."
          kubectl rollout undo deployment/xpeditis-backend -n ${{ env.K8S_NAMESPACE }} || true
          kubectl rollout undo deployment/xpeditis-frontend -n ${{ env.K8S_NAMESPACE }} || true
          kubectl rollout status deployment/xpeditis-backend -n ${{ env.K8S_NAMESPACE }} --timeout=120s || true
          kubectl rollout status deployment/xpeditis-frontend -n ${{ env.K8S_NAMESPACE }} --timeout=120s || true
          echo "Previous version restored."

  # ──────────────────────────────────────────────────────────────
  # 3. Smoke Tests
  #    kubectl rollout status already verifies pod readiness.
  #    These confirm the full network path:
  #    Cloudflare → Hetzner LB → Traefik → pod.
  # ──────────────────────────────────────────────────────────────
  smoke-tests:
    name: Smoke Tests
    runs-on: ubuntu-latest
    needs: deploy

    steps:
      - name: Wait for LB propagation
        run: sleep 30

      - name: Health check — Backend
        run: |
          for i in {1..12}; do
            STATUS=$(curl -s -o /dev/null -w "%{http_code}" --max-time 10 \
              "${{ secrets.PROD_BACKEND_URL }}/api/v1/health" 2>/dev/null || echo "000")
            echo "  Attempt $i: HTTP $STATUS"
            if [ "$STATUS" = "200" ]; then echo "Backend healthy."; exit 0; fi
            sleep 15
          done
          echo "CRITICAL: Backend unreachable after rollout."
          exit 1

      - name: Health check — Frontend
        run: |
          for i in {1..12}; do
            STATUS=$(curl -s -o /dev/null -w "%{http_code}" --max-time 10 \
              "${{ secrets.PROD_FRONTEND_URL }}" 2>/dev/null || echo "000")
            echo "  Attempt $i: HTTP $STATUS"
            if [ "$STATUS" = "200" ]; then echo "Frontend healthy."; exit 0; fi
            sleep 15
          done
          echo "CRITICAL: Frontend unreachable after rollout."
          exit 1

  # ──────────────────────────────────────────────────────────────
  # 4. Deployment Summary
  # ──────────────────────────────────────────────────────────────
  summary:
    name: Deployment Summary
    runs-on: ubuntu-latest
    needs: [promote-images, smoke-tests]
    if: success()

    steps:
      - name: Write summary
        run: |
          echo "## Production Deployment" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo "| | |" >> $GITHUB_STEP_SUMMARY
          echo "|---|---|" >> $GITHUB_STEP_SUMMARY
          echo "| **Commit** | \`${{ github.sha }}\` |" >> $GITHUB_STEP_SUMMARY
          echo "| **Backend** | \`${{ needs.promote-images.outputs.backend-image }}\` |" >> $GITHUB_STEP_SUMMARY
          echo "| **Frontend** | \`${{ needs.promote-images.outputs.frontend-image }}\` |" >> $GITHUB_STEP_SUMMARY
          echo "| **Source** | Promoted from \`preprod\` tag — no rebuild |" >> $GITHUB_STEP_SUMMARY
          echo "| **Cluster** | Hetzner k3s — namespace \`xpeditis-prod\` |" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo "To rollback: [Run rollback workflow](${{ github.server_url }}/${{ github.repository }}/actions/workflows/rollback.yml)" >> $GITHUB_STEP_SUMMARY

  # ──────────────────────────────────────────────────────────────
  # Discord — Success
  # ──────────────────────────────────────────────────────────────
  notify-success:
    name: Notify Success
    runs-on: ubuntu-latest
    needs: [promote-images, smoke-tests]
    if: success()

    steps:
      - name: Send Discord notification
        run: |
          curl -s -H "Content-Type: application/json" -d '{
            "embeds": [{
              "title": "🚀 Production Deployed & Healthy",
              "color": 3066993,
              "fields": [
                {"name": "Author", "value": "${{ github.actor }}", "inline": true},
                {"name": "Version", "value": "`prod-${{ needs.promote-images.outputs.short-sha }}`", "inline": true},
                {"name": "Commit", "value": "[`${{ github.sha }}`](${{ github.event.head_commit.url }})", "inline": false},
                {"name": "Registry", "value": "Scaleway — promoted from `preprod`, no rebuild", "inline": false},
                {"name": "Cluster", "value": "Hetzner k3s — `xpeditis-prod`", "inline": false},
                {"name": "Workflow", "value": "[${{ github.workflow }}](${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }})", "inline": false}
              ],
              "footer": {"text": "Xpeditis CI/CD • Production"}
            }]
          }' ${{ secrets.DISCORD_WEBHOOK_URL }}

  # ──────────────────────────────────────────────────────────────
  # Discord — Failure (CRITICAL)
  # ──────────────────────────────────────────────────────────────
  notify-failure:
    name: Notify Failure
    runs-on: ubuntu-latest
    needs: [promote-images, deploy, smoke-tests]
    if: failure()

    steps:
      - name: Send Discord notification
        run: |
          curl -s -H "Content-Type: application/json" -d '{
            "content": "@here PRODUCTION DEPLOYMENT FAILED",
            "embeds": [{
              "title": "🔴 PRODUCTION PIPELINE FAILED",
              "description": "Auto-rollback was triggered if deployment failed. Check rollout history.",
              "color": 15158332,
              "fields": [
                {"name": "Author", "value": "${{ github.actor }}", "inline": true},
                {"name": "Commit", "value": "[`${{ github.sha }}`](${{ github.event.head_commit.url }})", "inline": true},
                {"name": "Workflow", "value": "[${{ github.workflow }}](${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }})", "inline": false},
                {"name": "Manual rollback", "value": "[Run rollback workflow](${{ github.server_url }}/${{ github.repository }}/actions/workflows/rollback.yml)", "inline": false}
              ],
              "footer": {"text": "Xpeditis CI/CD • Production"}
            }]
          }' ${{ secrets.DISCORD_WEBHOOK_URL }}