#!/usr/bin/env bash
set -euo pipefail

KUBECONFIG="${KUBECONFIG:-${KUBECONFIG_PATH:-${HOME}/.kube/config}}"

section() {
    printf '\n== %s ==\n' "$1"
}

run_optional() {
    local label="$1"
    shift

    printf '\n-- %s\n' "${label}"
    "$@" 2>&1 || true
}

host_capacity() {
    section "Debian Host"
    run_optional "memory" free -h
    run_optional "disk" df -h / /data /var/lib/docker
    if command -v docker >/dev/null 2>&1; then
        run_optional "docker disk usage" sudo docker system df
        run_optional "largest docker volumes" sudo docker system df -v
    else
        printf 'docker not installed\n'
    fi
}

kubernetes_capacity() {
    section "Kubernetes"
    if ! command -v kubectl >/dev/null 2>&1 || [[ ! -s "${KUBECONFIG}" ]]; then
        printf 'kubectl or kubeconfig unavailable\n'
        return 0
    fi

    run_optional "nodes" kubectl --kubeconfig "${KUBECONFIG}" get nodes -o wide
    run_optional "node resource summary" kubectl --kubeconfig "${KUBECONFIG}" describe nodes
    run_optional "top nodes" kubectl --kubeconfig "${KUBECONFIG}" top nodes
    run_optional "top pods" kubectl --kubeconfig "${KUBECONFIG}" top pods -A --sort-by=memory
    run_optional "PVCs" kubectl --kubeconfig "${KUBECONFIG}" get pvc -A -o wide
    run_optional "PVs" kubectl --kubeconfig "${KUBECONFIG}" get pv -o wide

    printf '\n-- pods without resource requests or limits\n'
    kubectl --kubeconfig "${KUBECONFIG}" get pods -A -o jsonpath='{range .items[*]}{.metadata.namespace}{"/"}{.metadata.name}{" "}{range .spec.containers[*]}{.name}{":cpuReq="}{.resources.requests.cpu}{",memReq="}{.resources.requests.memory}{",memLimit="}{.resources.limits.memory}{" "}{end}{"\n"}{end}' 2>/dev/null |
        awk '/cpuReq=,|memReq=,|memLimit=,/ { print }' || true
}

pimox_capacity() {
    local pimox_host="${LAB_PIMOX_HOST:-${TF_VAR_pimox_host:-192.168.100.80}}"
    local pimox_user="${LAB_PIMOX_USER:-${TF_VAR_pimox_user:-jv}}"
    local pimox_key="${LAB_PIMOX_SSH_KEY_PATH:-${TF_VAR_pimox_ssh_key_path:-${HOME}/.ssh/id_ed25519}}"

    section "Pimox"
    ssh -i "${pimox_key}" -o BatchMode=yes -o ConnectTimeout=10 -o StrictHostKeyChecking=accept-new "${pimox_user}@${pimox_host}" '
set +e
echo "-- host memory"
free -h
echo
echo "-- storage"
df -h / /data 2>/dev/null || df -h
echo
echo "-- pvesm"
sudo pvesm status 2>/dev/null || true
echo
echo "-- VMs"
sudo qm list 2>/dev/null || true
echo
echo "-- running VM configs"
for vmid in $(sudo qm list 2>/dev/null | awk "NR > 1 {print \$1}"); do
  echo "VM ${vmid}"
  sudo qm config "${vmid}" 2>/dev/null | awk "/^(memory|cores|sockets|scsi|virtio|sata|ide)[0-9]*:|^memory:|^cores:|^sockets:/"
done
' || printf 'unable to reach Pimox host %s@%s\n' "${pimox_user}" "${pimox_host}"
}

rpi_capacity() {
    local rpi_host="${LAB_RPI_HOST:-${LAB_RASPBERRY_HOST:-192.168.100.89}}"
    local rpi_user="${LAB_RPI_USER:-${LAB_RASPBERRY_USER:-jv}}"
    local rpi_key="${LAB_RPI_SSH_KEY_PATH:-${LAB_RASPBERRY_SSH_KEY_PATH:-${HOME}/.ssh/id_ed25519}}"

    section "RPi4"
    ssh -i "${rpi_key}" -o BatchMode=yes -o ConnectTimeout=10 -o StrictHostKeyChecking=accept-new "${rpi_user}@${rpi_host}" '
set +e
echo "-- memory"
free -h
echo
echo "-- disk"
df -h / /nvme-storage /var/lib/docker 2>/dev/null || df -h
echo
echo "-- docker root"
sudo docker info --format "{{.DockerRootDir}}" 2>/dev/null || true
echo
echo "-- docker disk usage"
sudo docker system df 2>/dev/null || true
' || printf 'unable to reach RPi host %s@%s\n' "${rpi_user}" "${rpi_host}"
}

summary() {
    section "Capacity Guidance"
    cat <<'EOF'
Use this report to decide placement:
- Prefer Kubernetes app workloads on Pimox workers with SSD-backed storage.
- Keep Debian control-plane headroom for Docker, Gitea, registry, Ollama, and kubeadm.
- Treat Orange Pi VM disks as rebuildable capacity, not durable backup storage.
- Keep RPi4 focused on DNS/Uptime Kuma/light services until NVMe stability is proven.
- Add capacity only when CPU, memory, and disk all have margin; storage alone is not enough.
EOF
}

main() {
    host_capacity
    kubernetes_capacity
    pimox_capacity
    rpi_capacity
    summary
}

main "$@"