#!/bin/bash

# Copyright 2015 The Kubernetes Authors All rights reserved.
#
# Licensed 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 specific language governing permissions and
# limitations under the License.

# Common utilites for kube-up/kube-down

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

KUBE_ROOT=$(dirname "${BASH_SOURCE}")/..

DEFAULT_KUBECONFIG="${HOME}/.kube/config"

# KUBE_RELEASE_VERSION_REGEX matches things like "v1.2.3" or "v1.2.3-alpha.4"
#
# NOTE This must match the version_regex in build/common.sh
# kube::release::parse_and_validate_release_version()
KUBE_RELEASE_VERSION_REGEX="^v(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)(-(beta|alpha)\\.(0|[1-9][0-9]*))?$"

# KUBE_CI_VERSION_REGEX matches things like "v1.2.3-alpha.4.56+abcdefg" This
#
# NOTE This must match the version_regex in build/common.sh
# kube::release::parse_and_validate_ci_version()
KUBE_CI_VERSION_REGEX="^v(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)-(beta|alpha)\\.(0|[1-9][0-9]*)(\\.(0|[1-9][0-9]*)\\+[-0-9a-z]*)?$"


# Generate kubeconfig data for the created cluster.
# Assumed vars:
#   KUBE_USER
#   KUBE_PASSWORD
#   KUBE_MASTER_IP
#   KUBECONFIG
#   CONTEXT
#
# If the apiserver supports bearer auth, also provide:
#   KUBE_BEARER_TOKEN
#
# The following can be omitted for --insecure-skip-tls-verify
#   KUBE_CERT
#   KUBE_KEY
#   CA_CERT
function create-kubeconfig() {
  local kubectl="${KUBE_ROOT}/cluster/kubectl.sh"

  export KUBECONFIG=${KUBECONFIG:-$DEFAULT_KUBECONFIG}
  # KUBECONFIG determines the file we write to, but it may not exist yet
  if [[ ! -e "${KUBECONFIG}" ]]; then
    mkdir -p $(dirname "${KUBECONFIG}")
    touch "${KUBECONFIG}"
  fi
  local cluster_args=(
      "--server=${KUBE_SERVER:-https://${KUBE_MASTER_IP}}"
  )
  if [[ -z "${CA_CERT:-}" ]]; then
    cluster_args+=("--insecure-skip-tls-verify=true")
  else
    cluster_args+=(
      "--certificate-authority=${CA_CERT}"
      "--embed-certs=true"
    )
  fi

  local user_args=()
  if [[ ! -z "${KUBE_BEARER_TOKEN:-}" ]]; then
    user_args+=(
     "--token=${KUBE_BEARER_TOKEN}"
    )
  elif [[ ! -z "${KUBE_USER:-}" && ! -z "${KUBE_PASSWORD:-}" ]]; then
    user_args+=(
     "--username=${KUBE_USER}"
     "--password=${KUBE_PASSWORD}"
    )
  fi
  if [[ ! -z "${KUBE_CERT:-}" && ! -z "${KUBE_KEY:-}" ]]; then
    user_args+=(
     "--client-certificate=${KUBE_CERT}"
     "--client-key=${KUBE_KEY}"
     "--embed-certs=true"
    )
  fi

  "${kubectl}" config set-cluster "${CONTEXT}" "${cluster_args[@]}"
  if [[ -n "${user_args[@]:-}" ]]; then
    "${kubectl}" config set-credentials "${CONTEXT}" "${user_args[@]}"
  fi
  "${kubectl}" config set-context "${CONTEXT}" --cluster="${CONTEXT}" --user="${CONTEXT}"
  "${kubectl}" config use-context "${CONTEXT}"  --cluster="${CONTEXT}"

  # If we have a bearer token, also create a credential entry with basic auth
  # so that it is easy to discover the basic auth password for your cluster
  # to use in a web browser.
  if [[ ! -z "${KUBE_BEARER_TOKEN:-}" && ! -z "${KUBE_USER:-}" && ! -z "${KUBE_PASSWORD:-}" ]]; then
    "${kubectl}" config set-credentials "${CONTEXT}-basic-auth" "--username=${KUBE_USER}" "--password=${KUBE_PASSWORD}"
  fi

   echo "Wrote config for ${CONTEXT} to ${KUBECONFIG}"
}

# Clear kubeconfig data for a context
# Assumed vars:
#   KUBECONFIG
#   CONTEXT
function clear-kubeconfig() {
  export KUBECONFIG=${KUBECONFIG:-$DEFAULT_KUBECONFIG}
  local kubectl="${KUBE_ROOT}/cluster/kubectl.sh"
  "${kubectl}" config unset "clusters.${CONTEXT}"
  "${kubectl}" config unset "users.${CONTEXT}"
  "${kubectl}" config unset "users.${CONTEXT}-basic-auth"
  "${kubectl}" config unset "contexts.${CONTEXT}"

  local cc=$("${kubectl}" config view -o jsonpath='{.current-context}')
  if [[ "${cc}" == "${CONTEXT}" ]]; then
    "${kubectl}" config unset current-context
  fi

  echo "Cleared config for ${CONTEXT} from ${KUBECONFIG}"
}


function tear_down_alive_resources() {
  local kubectl="${KUBE_ROOT}/cluster/kubectl.sh"
  "${kubectl}" delete rc --all || true
  "${kubectl}" delete pods --all || true
  "${kubectl}" delete svc --all || true
  "${kubectl}" delete pvc --all || true
}

# Gets username, password for the current-context in kubeconfig, if they exist.
# Assumed vars:
#   KUBECONFIG  # if unset, defaults to global
#   KUBE_CONTEXT  # if unset, defaults to current-context
#
# Vars set:
#   KUBE_USER
#   KUBE_PASSWORD
#
# KUBE_USER,KUBE_PASSWORD will be empty if no current-context is set, or
# the current-context user does not exist or contain basicauth entries.
function get-kubeconfig-basicauth() {
  export KUBECONFIG=${KUBECONFIG:-$DEFAULT_KUBECONFIG}

  local cc=$("${KUBE_ROOT}/cluster/kubectl.sh" config view -o jsonpath="{.current-context}")
  if [[ ! -z "${KUBE_CONTEXT:-}" ]]; then
    cc="${KUBE_CONTEXT}"
  fi
  local user=$("${KUBE_ROOT}/cluster/kubectl.sh" config view -o jsonpath="{.contexts[?(@.name == \"${cc}\")].context.user}")
  KUBE_USER=$("${KUBE_ROOT}/cluster/kubectl.sh" config view -o jsonpath="{.users[?(@.name == \"${user}\")].user.username}")
  KUBE_PASSWORD=$("${KUBE_ROOT}/cluster/kubectl.sh" config view -o jsonpath="{.users[?(@.name == \"${user}\")].user.password}")
}

# Generate basic auth user and password.

# Vars set:
#   KUBE_USER
#   KUBE_PASSWORD
function gen-kube-basicauth() {
    KUBE_USER=admin
    KUBE_PASSWORD=$(python -c 'import string,random; print "".join(random.SystemRandom().choice(string.ascii_letters + string.digits) for _ in range(16))')
}

# Get the bearer token for the current-context in kubeconfig if one exists.
# Assumed vars:
#   KUBECONFIG  # if unset, defaults to global
#   KUBE_CONTEXT  # if unset, defaults to current-context
#
# Vars set:
#   KUBE_BEARER_TOKEN
#
# KUBE_BEARER_TOKEN will be empty if no current-context is set, or the
# current-context user does not exist or contain a bearer token entry.
function get-kubeconfig-bearertoken() {
  export KUBECONFIG=${KUBECONFIG:-$DEFAULT_KUBECONFIG}

  local cc=$("${KUBE_ROOT}/cluster/kubectl.sh" config view -o jsonpath="{.current-context}")
  if [[ ! -z "${KUBE_CONTEXT:-}" ]]; then
    cc="${KUBE_CONTEXT}"
  fi
  local user=$("${KUBE_ROOT}/cluster/kubectl.sh" config view -o jsonpath="{.contexts[?(@.name == \"${cc}\")].context.user}")
  KUBE_BEARER_TOKEN=$("${KUBE_ROOT}/cluster/kubectl.sh" config view -o jsonpath="{.users[?(@.name == \"${user}\")].user.token}")
}

# Generate bearer token.
#
# Vars set:
#   KUBE_BEARER_TOKEN
function gen-kube-bearertoken() {
    KUBE_BEARER_TOKEN=$(dd if=/dev/urandom bs=128 count=1 2>/dev/null | base64 | tr -d "=+/" | dd bs=32 count=1 2>/dev/null)
}


function load-or-gen-kube-basicauth() {
  if [[ ! -z "${KUBE_CONTEXT:-}" ]]; then
    get-kubeconfig-basicauth
  fi

  if [[ -z "${KUBE_USER:-}" || -z "${KUBE_PASSWORD:-}" ]]; then
    gen-kube-basicauth
  fi
}

function load-or-gen-kube-bearertoken() {
  if [[ ! -z "${KUBE_CONTEXT:-}" ]]; then
    get-kubeconfig-bearertoken
  fi
  if [[ -z "${KUBE_BEARER_TOKEN:-}" ]]; then
    gen-kube-bearertoken
  fi
}

# Get the master IP for the current-context in kubeconfig if one exists.
#
# Assumed vars:
#   KUBECONFIG  # if unset, defaults to global
#   KUBE_CONTEXT  # if unset, defaults to current-context
#
# Vars set:
#   KUBE_MASTER_URL
#
# KUBE_MASTER_URL will be empty if no current-context is set, or the
# current-context user does not exist or contain a server entry.
function detect-master-from-kubeconfig() {
  export KUBECONFIG=${KUBECONFIG:-$DEFAULT_KUBECONFIG}

  local cc=$("${KUBE_ROOT}/cluster/kubectl.sh" config view -o jsonpath="{.current-context}")
  if [[ ! -z "${KUBE_CONTEXT:-}" ]]; then
    cc="${KUBE_CONTEXT}"
  fi
  local cluster=$("${KUBE_ROOT}/cluster/kubectl.sh" config view -o jsonpath="{.contexts[?(@.name == \"${cc}\")].context.cluster}")
  KUBE_MASTER_URL=$("${KUBE_ROOT}/cluster/kubectl.sh" config view -o jsonpath="{.clusters[?(@.name == \"${cluster}\")].cluster.server}")
}

# Sets KUBE_VERSION variable to the proper version number (e.g. "v1.0.6",
# "v1.2.0-alpha.1.881+376438b69c7612") or a version' publication of the form
# <bucket>/<version> (e.g. "release/stable",' "ci/latest-1").
#
# See the docs on getting builds for more information about version
# publication.
#
# Args:
#   $1 version string from command line
# Vars set:
#   KUBE_VERSION
function set_binary_version() {
  if [[ "${1}" =~ "/" ]]; then
    KUBE_VERSION=$(gsutil cat gs://kubernetes-release/${1}.txt)
  else
    KUBE_VERSION=${1}
  fi
}

# Figure out which binary use on the server and assure it is available.
# If KUBE_VERSION is specified use binaries specified by it, otherwise
# use local dev binaries.
#
# Assumed vars:
#   KUBE_VERSION
#   KUBE_RELEASE_VERSION_REGEX
#   KUBE_CI_VERSION_REGEX
# Vars set:
#   KUBE_TAR_HASH
#   SERVER_BINARY_TAR_URL
#   SERVER_BINARY_TAR_HASH
#   SALT_TAR_URL
#   SALT_TAR_HASH
function tars_from_version() {
  if [[ -z "${KUBE_VERSION-}" ]]; then
    find-release-tars
    upload-server-tars
  elif [[ ${KUBE_VERSION} =~ ${KUBE_RELEASE_VERSION_REGEX} ]]; then
    SERVER_BINARY_TAR_URL="https://storage.googleapis.com/kubernetes-release/release/${KUBE_VERSION}/kubernetes-server-linux-amd64.tar.gz"
    SALT_TAR_URL="https://storage.googleapis.com/kubernetes-release/release/${KUBE_VERSION}/kubernetes-salt.tar.gz"
  elif [[ ${KUBE_VERSION} =~ ${KUBE_CI_VERSION_REGEX} ]]; then
    SERVER_BINARY_TAR_URL="https://storage.googleapis.com/kubernetes-release/ci/${KUBE_VERSION}/kubernetes-server-linux-amd64.tar.gz"
    SALT_TAR_URL="https://storage.googleapis.com/kubernetes-release/ci/${KUBE_VERSION}/kubernetes-salt.tar.gz"
  else
    echo "Version doesn't match regexp" >&2
    exit 1
  fi
  if ! SERVER_BINARY_TAR_HASH=$(curl -Ss --fail "${SERVER_BINARY_TAR_URL}.sha1"); then
    echo "Failure trying to curl release .sha1"
  fi
  if ! SALT_TAR_HASH=$(curl -Ss --fail "${SALT_TAR_URL}.sha1"); then
    echo "Failure trying to curl Salt tar .sha1"
  fi

  if ! curl -Ss --head "${SERVER_BINARY_TAR_URL}" >&/dev/null; then
    echo "Can't find release at ${SERVER_BINARY_TAR_URL}" >&2
    exit 1
  fi
  if ! curl -Ss --head "${SALT_TAR_URL}" >&/dev/null; then
    echo "Can't find Salt tar at ${SALT_TAR_URL}" >&2
    exit 1
  fi
}

# Verify and find the various tar files that we are going to use on the server.
#
# Assumed vars:
#   KUBE_ROOT
# Vars set:
#   SERVER_BINARY_TAR
#   SALT_TAR
function find-release-tars() {
  SERVER_BINARY_TAR="${KUBE_ROOT}/server/kubernetes-server-linux-amd64.tar.gz"
  if [[ ! -f "$SERVER_BINARY_TAR" ]]; then
    SERVER_BINARY_TAR="${KUBE_ROOT}/_output/release-tars/kubernetes-server-linux-amd64.tar.gz"
  fi
  if [[ ! -f "$SERVER_BINARY_TAR" ]]; then
    echo "!!! Cannot find kubernetes-server-linux-amd64.tar.gz" >&2
    exit 1
  fi

  SALT_TAR="${KUBE_ROOT}/server/kubernetes-salt.tar.gz"
  if [[ ! -f "$SALT_TAR" ]]; then
    SALT_TAR="${KUBE_ROOT}/_output/release-tars/kubernetes-salt.tar.gz"
  fi
  if [[ ! -f "$SALT_TAR" ]]; then
    echo "!!! Cannot find kubernetes-salt.tar.gz" >&2
    exit 1
  fi
}