name: Build & Deploy (develop)

# Runs on:
# - Pull requests targeting develop
# - Direct pushes to develop
# main is intentionally NOT included yet (no prod target configured)
on:
    push:
        branches:
            - develop
    pull_request:
        branches:
            - develop

jobs:
    build-and-deploy:
        runs-on: ubuntu-latest

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

            - name: Resolve image tag
              id: vars
              run: |
                  # For PRs, gitea.sha is a temporary merge commit — use the real
                  # PR head commit instead so tags map to actual git history.
                  FULL_SHA="${{ gitea.event.pull_request.head.sha || gitea.sha }}"
                  SHORT_SHA="${FULL_SHA:0:7}"
                  BUILD_TIME=$(date -u +%Y%m%d-%H%M%S)
                  echo "sha=${SHORT_SHA}" >> "$GITHUB_OUTPUT"
                  echo "tag=${BUILD_TIME}-${SHORT_SHA}" >> "$GITHUB_OUTPUT"

            - name: Build Docker image (tagged by UTC build time and commit SHA)
              run: |
                  docker build -t robot-market:${{ steps.vars.outputs.tag }} .

            - name: Save previous tag for rollback
              id: backup
              run: |
                  if [ -f /opt/robot-market-front/.env ]; then
                    cp /opt/robot-market-front/.env /opt/robot-market-front/.env.previous
                    echo "available=true" >> "$GITHUB_OUTPUT"
                  fi

            - name: Point compose at this build
              run: |
                  echo "IMAGE_TAG=${{ steps.vars.outputs.tag }}" > /opt/robot-market-front/.env

            - name: Deploy via compose
              id: deploy
              run: |
                  docker compose --env-file /opt/robot-market-front/.env \
                    -f /opt/robot-market-front/docker-compose.yml \
                    up -d --force-recreate

            - name: Health check (retries for ~30s)
              id: health
              run: |
                  for i in $(seq 1 15); do
                    if docker exec robot-market node -e "
                      require('http').get('http://localhost:3000', res => {
                        process.exit(res.statusCode < 400 ? 0 : 1);
                      }).on('error', () => process.exit(1));
                    " 2>/dev/null; then
                      echo "Container is healthy"
                      exit 0
                    fi
                    echo "Not ready yet, retrying..."
                    sleep 2
                  done
                  echo "Health check failed after 30s"
                  exit 1

            - name: Roll back after deployment or health check failure
              if: ${{ failure() && steps.backup.outputs.available == 'true' && (steps.deploy.outcome == 'failure' || steps.health.outcome == 'failure') }}
              run: |
                  if [ -f /opt/robot-market-front/.env.previous ]; then
                    cp /opt/robot-market-front/.env.previous /opt/robot-market-front/.env
                    docker compose --env-file /opt/robot-market-front/.env \
                      -f /opt/robot-market-front/docker-compose.yml \
                      up -d --force-recreate
                    echo "Rolled back to previous image."
                  else
                    echo "No previous deploy recorded — nothing to roll back to."
                  fi

            - name: Clean up dangling (untagged) layers
              run: docker image prune -f

            - name: Prune old build-tagged images (keep last 5)
              run: |
                  KEEP=5
                  CURRENT_TAG=$(grep IMAGE_TAG /opt/robot-market-front/.env 2>/dev/null | cut -d= -f2)
                  PREVIOUS_TAG=$(grep IMAGE_TAG /opt/robot-market-front/.env.previous 2>/dev/null | cut -d= -f2)

                  docker images robot-market --format '{{.Tag}}	{{.CreatedAt}}' \
                    | sort -t"	" -k2 -r \
                    | tail -n +$((KEEP + 1)) \
                    | cut -f1 \
                    | while read -r tag; do
                        if [ "$tag" != "$CURRENT_TAG" ] && [ "$tag" != "$PREVIOUS_TAG" ] && [ "$tag" != "<none>" ]; then
                          echo "Removing old image robot-market:$tag"
                          docker rmi "robot-market:$tag" 2>/dev/null || true
                        fi
                      done