#!/usr/bin/env bash
# This script only fits for Linux, macOS adaptation will come soon

set -o errexit
set -o nounset
set -o pipefail

function usage() {
  echo "This script starts a kube cluster by kind."
  echo "Usage: hack/create-cluster.sh <CLUSTER_NAME> [KUBECONFIG]"
  echo "Example: hack/create-cluster.sh host /root/.kube/karmada.config"
}

CLUSTER_VERSION=${CLUSTER_VERSION:-"kindest/node:v1.23.4"}

if [[ $# -lt 1 ]]; then
  usage
  exit 1
fi

CLUSTER_NAME=$1
if [[ -z "${CLUSTER_NAME}" ]]; then
  usage
  exit 1
fi

if [[ -z "${2-}" ]]; then
  KUBECONFIG=$KUBECONFIG
else
  KUBECONFIG=$2
fi

if [[ -z "${KUBECONFIG}" ]]; then
  usage
  exit 1
fi

# check kind
REPO_ROOT=$(dirname "${BASH_SOURCE[0]}")/..
# shellcheck source=util.sh
source "${REPO_ROOT}"/hack/util.sh
util::cmd_must_exist "kind"

if [ -f "${KUBECONFIG}" ];then
  echo "kubeconfig file is existed, new config will append to it."
  if kubectl config get-contexts "${CLUSTER_NAME}" --kubeconfig="${KUBECONFIG}"> /dev/null 2>&1;
  then
    echo "ERROR: failed to create new cluster for context '${CLUSTER_NAME}' existed in ${KUBECONFIG}. please remove it (use 'kubectl config delete-context') if your want to overwrite it."
    exit 1
  fi
fi

function rand() {
    min=$1
    max=$(($2-$min+1))
    num=$(date +%s%N)
    echo $(($num%$max+$min))
}

function generate_cidr() {
    local val=$(rand 1 254)
    echo "$1.${val}.0.0/16"
}

POD_CIDR=${POD_CIDR:-""}
if [[ -z "${POD_CIDR}" ]]; then
    POD_CIDR=$(generate_cidr 10)
fi

SERVICE_CIDR=${SERVICE_CIDR:-""}
if [[ -z "${SERVICE_CIDR}" ]]; then
    SERVICE_CIDR=$(generate_cidr 100)
fi

function deploy_weave_cni() {
  echo "Applying weave network..."
  kubectl --kubeconfig=$1 apply -f "https://cloud.weave.works/k8s/net?k8s-version=$(kubectl --kubeconfig=$1 version | base64 | tr -d '\n')&env.IPALLOC_RANGE=$2"
  echo "Waiting for weave-net pods to be ready..."
  kubectl --kubeconfig=$1 wait --for=condition=Ready pods -l name=weave-net -n kube-system --timeout=10m
  echo "Waiting for core-dns deployment to be ready..."
  kubectl --kubeconfig=$1 -n kube-system rollout status deploy/coredns --timeout=5m
}

#generate for kindClusterConfig
TEMP_PATH=$(mktemp -d)
cp -rf "${REPO_ROOT}"/artifacts/kindClusterConfig/general-config.yaml "${TEMP_PATH}"/"${CLUSTER_NAME}"-config.yaml
sed -i'' -e "s#{{disable_cni}}#true#g" "${TEMP_PATH}"/"${CLUSTER_NAME}"-config.yaml
sed -i'' -e "s#{{pod_cidr}}#${POD_CIDR}#g" "${TEMP_PATH}"/"${CLUSTER_NAME}"-config.yaml
sed -i'' -e "s#{{service_cidr}}#${SERVICE_CIDR}#g" "${TEMP_PATH}"/"${CLUSTER_NAME}"-config.yaml

kind create cluster --name "${CLUSTER_NAME}" --kubeconfig="${KUBECONFIG}" --image="${CLUSTER_VERSION}" --config="${TEMP_PATH}"/"${CLUSTER_NAME}"-config.yaml

# Kind cluster's context name contains a "kind-" prefix by default.
# Change context name to cluster name.
kubectl config rename-context "kind-${CLUSTER_NAME}" "${CLUSTER_NAME}" --kubeconfig="${KUBECONFIG}"

# Kind cluster uses `127.0.0.1` as kube-apiserver endpoint by default, thus kind clusters can't reach each other.
# So we need to update endpoint with container IP.
container_ip=$(docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' "${CLUSTER_NAME}-control-plane")
kubectl config set-cluster "kind-${CLUSTER_NAME}" --server="https://${container_ip}:6443" --kubeconfig="${KUBECONFIG}"

deploy_weave_cni "${KUBECONFIG}" "${POD_CIDR}"

echo "cluster \"${CLUSTER_NAME}\" is created successfully!"