#!/usr/bin/env bash

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# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
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# ----------------------------------------------------------------------------

set -x

K8S_VER=$2
if [[ "${K8S_VER}" == "" ]]; then
    K8S_VER="k8s-v1.15.4"
fi

function waitMinikube() {
  set +e
  kubectl cluster-info
  # This for loop waits until kubectl can access the api server that Minikube has created.
  for _ in {1..24}; do # Timeout for 240 seconds.
    kubectl get po --all-namespaces
    if [ $? -ne 1 ]; then
      break
    fi
    sleep 10
  done
  if ! kubectl get all --all-namespaces; then
    echo "Kubernetes failed to start"
    ps ax
    netstat -an
    docker images
    cat /var/lib/localkube/localkube.err
    printf '\n\n\n'
    kubectl cluster-info dump
    exit 1
  fi

  echo "Minikube is running"

  for _ in {1..6}; do # Timeout for 60 seconds.
    echo "$(sudo -E minikube ip) minikube.local" | sudo tee -a /etc/hosts
    ip=$(cat /etc/hosts | grep minikube.local | cut -d' ' -f1 | xargs)
    if [ -n "$ip" ]; then
      break
    fi
    sleep 10
  done

  ip=$(cat /etc/hosts | grep minikube.local | cut -d' ' -f1 | xargs)
  if [ -n "$ip" ]; then
    echo "minikube.local is mapped to $ip"
  else
    exit 1
  fi
}

# startMinikubeNone starts real kubernetes minikube with none driver. This requires `sudo`.
function startMinikubeNone() {
  export MINIKUBE_WANTUPDATENOTIFICATION=false
  export MINIKUBE_WANTREPORTERRORPROMPT=false
  export MINIKUBE_HOME=$HOME
  export CHANGE_MINIKUBE_NONE_USER=true

  # Troubleshoot problem with Docker build on some CircleCI machines.
  if [ -f /proc/sys/net/ipv4/ip_forward ]; then
    echo "IP forwarding setting: $(cat /proc/sys/net/ipv4/ip_forward)"
    echo "My hostname is:"
    hostname
    echo "My distro is:"
    cat /etc/*-release
    echo "Contents of /etc/sysctl.d/"
    ls -l /etc/sysctl.d/ || true
    echo "Contents of /etc/sysctl.conf"
    grep ip_forward /etc/sysctl.conf
    echo "Config files setting ip_forward"
    find /etc/sysctl.d/ -type f -exec grep ip_forward \{\} \; -print
    if [ "$(cat /proc/sys/net/ipv4/ip_forward)" -eq 0 ]; then
      whoami
      echo "Cannot build images without IPv4 forwarding, attempting to turn on forwarding"
      sudo sysctl -w net.ipv4.ip_forward=1
      if [ "$(cat /proc/sys/net/ipv4/ip_forward)" -eq 0 ]; then
        echo "Cannot build images without IPv4 forwarding"
        exit 1
      fi
    fi
  fi

  sudo -E minikube config set WantUpdateNotification false
  sudo -E minikube config set WantReportErrorPrompt false
  sudo -E minikube start --kubernetes-version=${K8S_VER#k8s-} --vm-driver=none
}

function stopMinikube() {
  sudo minikube stop
}

case "$1" in
  start) startMinikubeNone ;;
  stop) stopMinikube ;;
  wait) waitMinikube ;;
esac