name: Deploy

on:
  push:
    branches:
      - main

# Two overlapping deploys would race on the same container. Queue instead.
concurrency:
  group: deploy-production
  cancel-in-progress: false

env:
  IMAGE: git.ksan.dev/ksan/ksan.dev
  SITE_DIR: /home/deploy/websites/ksan.dev
  DOMAIN: ksan.dev

jobs:
  check:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: 20
          cache: npm
      - run: npm ci
      - run: npm run typecheck
      - run: npm run lint

  build:
    needs: check
    runs-on: ubuntu-latest
    outputs:
      tag: ${{ steps.meta.outputs.tag }}
    steps:
      - uses: actions/checkout@v4

      - id: meta
        run: echo "tag=$(echo "${{ github.sha }}" | cut -c1-12)" >> "$GITHUB_OUTPUT"

      - name: Log in to the Gitea registry
        env:
          REGISTRY_USER: ${{ secrets.REGISTRY_USER }}
          REGISTRY_TOKEN: ${{ secrets.REGISTRY_TOKEN }}
        run: echo "$REGISTRY_TOKEN" | docker login git.ksan.dev -u "$REGISTRY_USER" --password-stdin

      # PLANS_PAGES is a build arg: the codes are baked into the image via
      # generateStaticParams, so this image must only ever go to the private
      # package. Never push this repo's image to a public registry.
      - name: Build and push
        env:
          PLANS_PAGES: ${{ secrets.PLANS_PAGES }}
          TAG: ${{ steps.meta.outputs.tag }}
        run: |
          docker build \
            --build-arg PLANS_PAGES="$PLANS_PAGES" \
            -t "$IMAGE:$TAG" \
            -t "$IMAGE:latest" \
            .
          docker push "$IMAGE:$TAG"
          docker push "$IMAGE:latest"

  deploy:
    needs: build
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Configure SSH
        env:
          SSH_KEY: ${{ secrets.SSH_KEY }}
          SSH_KNOWN_HOSTS: ${{ secrets.SSH_KNOWN_HOSTS }}
        run: |
          mkdir -p ~/.ssh && chmod 700 ~/.ssh
          printf '%s\n' "$SSH_KEY" > ~/.ssh/id_ed25519
          chmod 600 ~/.ssh/id_ed25519
          # Pinned host key — never StrictHostKeyChecking=no on a deploy path.
          printf '%s\n' "$SSH_KNOWN_HOSTS" > ~/.ssh/known_hosts
          chmod 600 ~/.ssh/known_hosts

      - name: Ship compose file and deploy scripts
        env:
          SSH_HOST: ${{ secrets.SSH_HOST }}
          SSH_USER: ${{ secrets.SSH_USER }}
        run: |
          scp -i ~/.ssh/id_ed25519 \
            docker-compose.yaml deploy/deploy.sh deploy/rollback.sh \
            "$SSH_USER@$SSH_HOST:$SITE_DIR/"
          ssh -i ~/.ssh/id_ed25519 "$SSH_USER@$SSH_HOST" \
            "chmod +x $SITE_DIR/deploy.sh $SITE_DIR/rollback.sh"

      - name: Deploy
        env:
          SSH_HOST: ${{ secrets.SSH_HOST }}
          SSH_USER: ${{ secrets.SSH_USER }}
          TAG: ${{ needs.build.outputs.tag }}
        run: |
          ssh -i ~/.ssh/id_ed25519 "$SSH_USER@$SSH_HOST" \
            "IMAGE_TAG=$TAG $SITE_DIR/deploy.sh"

      # End-to-end, from outside the VPS: proves the container, the Traefik
      # router labels, the frontend network attachment and the cert all work.
      # A localhost probe on the VPS would miss a broken router rule.
      - name: Verify the site is serving
        run: |
          curl -fsS --retry 10 --retry-delay 3 --retry-connrefused \
            -o /dev/null "https://$DOMAIN/en"

      - name: Roll back
        if: failure()
        env:
          SSH_HOST: ${{ secrets.SSH_HOST }}
          SSH_USER: ${{ secrets.SSH_USER }}
        run: |
          ssh -i ~/.ssh/id_ed25519 "$SSH_USER@$SSH_HOST" "$SITE_DIR/rollback.sh"
          echo "::error::Deploy failed — rolled back to the last healthy build."
          exit 1