name: CI Pipeline for the Go API

on:
  push:
    branches:
      - master

jobs:
  docker-test:
    name: CI - Docker Image Build Test
    runs-on: docker-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v3

      - name: Build Docker image
        run: |
          docker build -t go-api-test .

  go-test:
    name: CI - Go Vet (basic static check)
    runs-on: docker-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v3

      - name: Check Go version
        run: go version

      - name: Go Vet (basic static check)
        run: go vet ./...

  go-build:
    name: CI - Go Build & Cross-Compile
    runs-on: docker-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v3

      - name: Check Go version
        run: go version
      
      - name: Build Linux binary
        run: |
          mkdir -p build
          go build -o build/go-api-linux main.go

      - name: Build Windows binary
        run: |
          GOOS=windows GOARCH=amd64 go build -o build/go-api.exe main.go

      - name: Show build output
        run: ls -lh build

      - name: Upload build artifacts
        uses: actions/upload-artifact@v3
        with:
          name: go-api-binaries
          path: build/

  docker-push:
    name: CD - Push Image to Gitea Registry
    runs-on: docker-latest
    needs: [docker-test, go-build]
    steps:
      - uses: actions/checkout@v3

      - name: Compute image tag
        run: |
          TAG="${GITHUB_SHA:-${{ github.sha }}}"
          echo "TAG=$TAG" >> $GITHUB_ENV
          echo "TAG_SHORT=${TAG:0:12}" >> $GITHUB_ENV
          echo "BASE_IMAGE=git.petyaserver.uk/${{ secrets.REGISTRY_USER }}/go-api" >> $GITHUB_ENV

      - name: Docker login
        env:
          REGISTRY_USER: ${{ secrets.REGISTRY_USER }}
          REGISTRY_PASSWORD: ${{ secrets.REGISTRY_PASSWORD }}
        run: |
          echo "$REGISTRY_PASSWORD" | docker login git.petyaserver.uk -u "$REGISTRY_USER" --password-stdin

      - name: Build (latest + sha)
        run: |
          docker build -t "$BASE_IMAGE:$TAG" -t "$BASE_IMAGE:latest" .

      - name: Push (latest + sha)
        run: |
          docker push "$BASE_IMAGE:$TAG"
          docker push "$BASE_IMAGE:latest"

  k8s-some-test:
    name: CD - Kubernetes Smoke Test
    runs-on: docker-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v3
      
      - name: Configure kubeconfig
        run: |
          mkdir -p ~/.kube
          echo "$KUBECONFIG_GITEA" > ~/.kube/config
          chmod 600 ~/.kube/config
        env:
          KUBECONFIG_GITEA: ${{ secrets.KUBECONFIG_GITEA }}
        
      - name: Kubectl test
        run: kubectl version --client

      - name: K3S Cluster Connection Test
        run: kubectl get nodes -o wide

  k8s-deploy:
    name: CD - Kubernetes Deployment
    runs-on: docker-latest
    needs: [go-build, k8s-some-test, docker-push]
    steps:
      - uses: actions/checkout@v3

      - name: Configure kubeconfig
        run: |
          mkdir -p ~/.kube
          echo "$KUBECONFIG_GITEA" > ~/.kube/config
          chmod 600 ~/.kube/config
        env:
          KUBECONFIG_GITEA: ${{ secrets.KUBECONFIG_GITEA }}

      - name: Compute image tag (again for this job)
        run: |
          TAG="${GITHUB_SHA:-${{ github.sha }}}"
          echo "TAG=$TAG" >> $GITHUB_ENV
          echo "BASE_IMAGE=git.petyaserver.uk/${{ secrets.REGISTRY_USER }}/go-api" >> $GITHUB_ENV
          echo "Will deploy image: ${BASE_IMAGE}:${TAG}"

      - name: Verify connection
        run: kubectl get nodes -o wide

      - name: Apply Deployment to Cluster
        run: kubectl apply -f k8s/deployment.yaml

      - name: Apply Service to Cluster
        run: kubectl apply -f k8s/service.yaml

      - name: Tag Image
        run: |
          kubectl set image deployment/go-api go-api="$BASE_IMAGE:$TAG" --record

      - name: Verify Rollout
        run: kubectl rollout status deployment/go-api --timeout=240s