#!/usr/bin/env bash

set -euo pipefail

# init_kerberos_test.sh
# Purpose:
# - Run Kerberos authentication checks inside a Kubernetes pod
# - Uses the prole-krb5-conf ConfigMap for krb5.conf

# Initialize SCRIPT_DIR
SCRIPT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)

ACTION=${1:-test}

# Load env
if [[ -n "${PROLE_HOME:-}" && -f "$PROLE_HOME/env.sh" ]]; then
  set --
  # shellcheck disable=SC1090
  source "$PROLE_HOME/env.sh"
elif [[ -f "$HOME/.prole/env.sh" ]]; then
  set --
  # shellcheck disable=SC1090
  source "$HOME/.prole/env.sh"
fi

NAMESPACE=${NAMESPACE:-default}
KRB5_REALM=${KRB5_REALM:-${REALM:-}}
KRB5_KDC=${KRB5_KDC:-}
KRB5_USER=${KRB5_USER:-${KRB5_USERNAME:-}}
KRB5_PASSWORD=${KRB5_PASSWORD:-}
KRB5_TEST_IMAGE=${KRB5_TEST_IMAGE:-${PROLE_KRB_TEST_IMAGE:-}}
KEEP_POD=${KEEP_POD:-0}
KRB5_TEST_HOST_NETWORK=${KRB5_TEST_HOST_NETWORK:-0}
KRB5_TEST_DNS_POLICY=${KRB5_TEST_DNS_POLICY:-}

ensure_tools() {
  for t in kubectl; do
    command -v "$t" >/dev/null || { echo "Missing required tool: $t" >&2; exit 1; }
  done
}

ensure_namespace() {
  if ! kubectl get namespace "$NAMESPACE" >/dev/null 2>&1; then
    echo "Creating namespace '$NAMESPACE' ..."
    kubectl create namespace "$NAMESPACE" >/dev/null 2>&1 || true
  fi
}

detect_image() {
  if [[ -n "$KRB5_TEST_IMAGE" ]]; then
    echo "$KRB5_TEST_IMAGE"
    return
  fi
  local version_file
  if [[ -n "${PROLE_HOME:-}" && -f "$PROLE_HOME/conf/postgresql/.version" ]]; then
    version_file="$PROLE_HOME/conf/postgresql/.version"
  elif [[ -f "$SCRIPT_DIR/../conf/postgresql/.version" ]]; then
    version_file="$SCRIPT_DIR/../conf/postgresql/.version"
  else
    version_file=""
  fi

  if [[ -n "$version_file" && -f "$version_file" ]]; then
    echo "prole-db:$(cat "$version_file" | tr -d '[:space:]')"
  else
    echo "prole-db:latest"
  fi
}

ensure_configmap() {
  if kubectl -n "$NAMESPACE" get configmap prole-krb5-conf >/dev/null 2>&1; then
    return
  fi
  echo "ConfigMap prole-krb5-conf not found. Running init_openbao.sh update..."
  if [[ -x "$SCRIPT_DIR/init_openbao.sh" ]]; then
    KRB5_REALM="$KRB5_REALM" KRB5_KDC="$KRB5_KDC" "$SCRIPT_DIR/init_openbao.sh" update || true
  fi
}

create_test_pod() {
  local pod_name="$1"
  local image="$2"
  local host_net_block=""
  if [[ "$KRB5_TEST_HOST_NETWORK" == "1" ]]; then
    local dns_policy
    dns_policy=${KRB5_TEST_DNS_POLICY:-Default}
    host_net_block=$'  hostNetwork: true\n  dnsPolicy: '"$dns_policy"$'\n'
  fi
  cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Pod
metadata:
  name: ${pod_name}
  namespace: ${NAMESPACE}
  labels:
    app: prole-kerberos-test
spec:
${host_net_block}  restartPolicy: Never
  containers:
    - name: kerberos-test
      image: ${image}
      command: ["sleep","3600"]
      volumeMounts:
        - name: krb5-conf
          mountPath: /etc/krb5.conf
          subPath: krb5.conf
  volumes:
    - name: krb5-conf
      configMap:
        name: prole-krb5-conf
        items:
          - key: krb5.conf
            path: krb5.conf
EOF
}

run_test() {
  ensure_tools
  ensure_namespace

  if [[ -z "$KRB5_REALM" || -z "$KRB5_USER" || -z "$KRB5_PASSWORD" || -z "$KRB5_KDC" ]]; then
    echo "ERROR: Missing Kerberos configuration. Ensure KRB5_REALM, KRB5_KDC, KRB5_USER, KRB5_PASSWORD are set." >&2
    exit 1
  fi

  ensure_configmap

  local image pod_name
  image=$(detect_image)
  pod_name="prole-krb-test-$(date +%s)"

  echo "Creating Kerberos test pod '$pod_name' in namespace '$NAMESPACE' using image '$image'..."
  create_test_pod "$pod_name" "$image"

  echo "Waiting for pod to become ready..."
  if ! kubectl -n "$NAMESPACE" wait --for=condition=Ready pod/"$pod_name" --timeout=90s; then
    echo "Pod did not become ready. Describing pod:"
    kubectl -n "$NAMESPACE" describe pod "$pod_name" || true
    if [[ "$KEEP_POD" != "1" ]]; then
      kubectl -n "$NAMESPACE" delete pod "$pod_name" --ignore-not-found
    fi
    exit 1
  fi

  echo "Checking for kinit in pod..."
  if ! kubectl -n "$NAMESPACE" exec "$pod_name" -- sh -c 'command -v kinit >/dev/null 2>&1'; then
    echo "ERROR: kinit not found in test pod image '$image'." >&2
    if [[ "$KEEP_POD" != "1" ]]; then
      kubectl -n "$NAMESPACE" delete pod "$pod_name" --ignore-not-found
    fi
    exit 1
  fi

  echo "Running kinit for ${KRB5_USER}@${KRB5_REALM} ..."
  if ! printf '%s\n' "$KRB5_PASSWORD" | kubectl -n "$NAMESPACE" exec -i "$pod_name" -- kinit "${KRB5_USER}@${KRB5_REALM}"; then
    echo "ERROR: kinit failed for ${KRB5_USER}@${KRB5_REALM}." >&2
    if [[ "$KEEP_POD" != "1" ]]; then
      kubectl -n "$NAMESPACE" delete pod "$pod_name" --ignore-not-found
    fi
    exit 1
  fi

  echo "Kerberos ticket cache:"
  kubectl -n "$NAMESPACE" exec "$pod_name" -- klist || true

  if [[ "${REALM_JOIN:-0}" == "1" ]]; then
    echo "Attempting realm join inside test pod..."
    if kubectl -n "$NAMESPACE" exec "$pod_name" -- sh -c 'command -v realm >/dev/null 2>&1'; then
      printf '%s\n' "$KRB5_PASSWORD" | kubectl -n "$NAMESPACE" exec -i "$pod_name" -- realm join --user "$KRB5_USER" "$KRB5_REALM" || true
    else
      echo "realm command not found in image; skipping realm join."
    fi
  fi

  if [[ "$KEEP_POD" != "1" ]]; then
    kubectl -n "$NAMESPACE" delete pod "$pod_name" --ignore-not-found
  else
    echo "KEEP_POD=1 set; leaving test pod running: $pod_name"
  fi
}

case "$ACTION" in
  test)
    run_test
    ;;
  cleanup)
    ensure_tools
    echo "Deleting kerberos test pods in namespace '$NAMESPACE'..."
    kubectl -n "$NAMESPACE" delete pod -l app=prole-kerberos-test --ignore-not-found
    ;;
  *)
    echo "Usage: $0 {test|cleanup}" >&2
    exit 2
    ;;
esac