#!/usr/bin/env bash

# Copyright 2018-2023 Open Networking Foundation (ONF) and the ONF Contributors
#
# 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.

# helmrepo.sh
# creates or updates a helm repo for publishing on the guide website
# Reference: https://github.com/helm/charts/blob/master/test/repo-sync.sh

set -eu -o pipefail

##-------------------##
##---]  GLOBALS  [---##
##-------------------##

# when not running under Jenkins, use current dir as workspace
WORKSPACE=${WORKSPACE:-.}

# directory to compare against, doesn't need to be present
OLD_REPO_DIR="${OLD_REPO_DIR:-cord-charts-repo}"
NEW_REPO_DIR="${NEW_REPO_DIR:-chart_repo}"

PUBLISH_URL="${PUBLISH_URL:-charts.opencord.org}"

## -----------------------------------------------------------------------
## Intent: Dispay called function with given output
## -----------------------------------------------------------------------
function func_echo()
{
    echo "** ${FUNCNAME[1]}: $*"
    return
}

## -----------------------------------------------------------------------
## Intent: Display given text and exit with shell error status.
## -----------------------------------------------------------------------
function error()
{
    echo "** ${BASH_SOURCE[0]}::${FUNCNAME[1]} ERROR: $*"
    exit 1
}

## -----------------------------------------------------------------------
## Intent: Gather a list of Chart.yaml files from the filesystem.
## -----------------------------------------------------------------------
function get_chart_yaml()
{
    local dir="$1"    ; shift
    declare -n ref=$1 ; shift

    readarray -t _charts < <(find "$dir" -name Chart.yaml -print | sort)
    ref=("${_charts[@]}")
    return
}

## -----------------------------------------------------------------------
## Intent: Update helm package dependencies
## -----------------------------------------------------------------------
function helm_deps_update()
{
    local dest="$1"; shift    # helm --destination

    if [[ -v dry_run ]]; then
	func_echo "helm package --dependency-update --destination $dest $chartdir"
    else
	helm package --dependency-update --destination "$dest" "$chartdir"
    fi
    return
}

## -----------------------------------------------------------------------
## Intent: Update helm package index
## -----------------------------------------------------------------------
function helm_index_publish()
{
    local repo_dir="$1"; shift    # helm --destination

    if [[ -v dry_run ]]; then
	func_echo "helm repo index $repo_dir --url https://${PUBLISH_URL}"
    else
	helm repo index "$repo_dir" --url https://"${PUBLISH_URL}"
    fi
    return
}

## -----------------------------------------------------------------------
## Intent: Update helm package index
## -----------------------------------------------------------------------
function helm_index_merge()
{
    local old_repo="$1" ; shift
    local new_repo="$1" ; shift

    declare -a cmd=()
    cmd+=('helm' 'repo' 'index')
    cmd+=('--url' "https://${PUBLISH_URL}")
    cmd+=('--merge' "${old_repo}/index.yaml" "$new_repo")

    if [[ -v dry_run ]]; then
	func_echo "${cmd[@]}"
    else
	"${cmd[@]}"
    fi
    return
}

## -----------------------------------------------------------------------
## Intent: Given a Chart.yaml file path return test directory where stored
## -----------------------------------------------------------------------
function chart_path_to_test_dir()
{
    local val="$1"    ; shift

# shellcheck disable=SC2178 
   declare -n ref=$1 ; shift # indirect var

    val="${val%/Chart.yaml}"  # dirname: prune /Chart.yaml
    val="${val##*/}"          # basename: test directory

# shellcheck disable=SC2034,SC2178
    ref="$val"                # Return value to caller
    return
}

## -----------------------------------------------------------------------
## Intent: Given a Chart.yaml file path return test directory where stored
## -----------------------------------------------------------------------
function create_helm_repo_new()
{
    local repo_dir="$1"; shift # NEW_REPO_DIR
    local work_dir="$1"; shift # WORKSPACE

    echo "Creating new helm repo: ${repo_dir}"

    declare -a charts=()
    get_chart_yaml "$work_dir" charts

    local chart
    for chart in "${charts[@]}";
    do
	echo
	func_echo "Chart.yaml: $chart"
	
	chartdir=''
	chart_path_to_test_dir "$chart" chartdir
	func_echo " Chart.dir: $chartdir"
	
	helm_deps_update "${repo_dir}"
    done
    
    helm_index_publish "${repo_dir}"
    return
}

##----------------##
##---]  MAIN  [---##
##----------------##

while [ $# -gt 0 ]; do
    arg="$1"; shift

    case "$arg" in
	-*debug) declare -g -i debug=1     ;;
	-*dry*)  declare -g -i dry_run=1   ;;
	-*help)
	    cat <<EOH
Usage: $0
  --debug       Enable debug mode
  --dry-run     Simulate helm calls
EOH
	    ;;	
	
	-*) echo "[SKIP] unknown switch [$arg]" ;;
	*) echo "[SKIP] unknown argument [$arg]" ;;
    esac
done


echo "# helmrepo.sh, using helm: $(helm version -c) #"

# create and clean NEW_REPO_DIR
mkdir -p "${NEW_REPO_DIR}"
rm -f "${NEW_REPO_DIR}"/*

# if OLD_REPO_DIR doesn't exist, generate packages and index in NEW_REPO_DIR
if [ ! -d "${OLD_REPO_DIR}" ]
then
    create_helm_repo_new "$NEW_REPO_DIR" "$WORKSPACE"
    echo
    echo "# helmrepo.sh Success! Generated new repo index in ${NEW_REPO_DIR}"

else
  # OLD_REPO_DIR exists, check for new charts and update only with changes
  echo "Found existing helm repo: ${OLD_REPO_DIR}, attempting update"

  # Loop and create chart packages, only if changed
  declare -a charts=()
  get_chart_yaml "$WORKSPACE" charts

  for chart in "${charts[@]}";
  do
      echo
      func_echo "Chart.yaml: $chart"

      chartdir=''
      chart_path_to_test_dir "$chart" chartdir
      func_echo " Chart.dir: $chartdir"

      # See if chart version changed from previous HEAD commit
      readarray -t chart_yaml_diff < <(git diff -p HEAD^ -- "$chart")
      
      if [[ ! -v chart_yaml_diff ]]; then
	  echo "Chart unchanged, not packaging: '${chartdir}'"

      elif [ ${#chart_yaml_diff} -gt 0 ]; then
	  # assumes that helmlint.sh and chart_version_check.sh have been run
	  # pre-merge, which ensures that all charts are valid and have their
	  # version updated in Chart.yaml

	  [[ -v new_version_string ]] && unset new_version_string

	  for line in "${chart_yaml_diff[@]}";
	  do
	      [[ -v debug ]] && func_echo "$line"

	      case "$line" in
		  # "-version: \"1.0.3\""
		  -version:*)
		      [[ ! -v debug ]] && func_echo "$line"
		      ;;

		  # "+version: \"1.0.4\""
		  +version:*)
		      [[ ! -v debug ]] && func_echo "$line"

		      readarray -d':' -t _fields <<<"$line" # split on delimiter
		      val="${_fields[1]}"
		      val="${val//[[:blank:]]}"
		      
		      # error detection: only assign when we have a value.
		      [ ${#val} -gt 0 ] && new_version_string="$val"
		      break
		      ;;
	      esac
	  done

	  [[ ! -v new_version_string ]] && error "Failed to detect version: in $chart"

	  echo "New version of chart ${chartdir}, creating package: ${new_version_string}"

	  helm_deps_update "1${NEW_REPO_DIR}"

      else
	  echo "Chart unchanged, not packaging: '${chartdir}'"
      fi    
  done

  ## -----------------------------------------------------------------------
  ## -----------------------------------------------------------------------
  readarray -t package_paths < <(find "${NEW_REPO_DIR}" -name '*.tgz' -print)
  declare -p package_paths
  
  # Check for collisions between old/new packages
  #  while IFS= read -r -d '' package_path
  for package_path in "${package_paths[@]}";
  do
      package="${package_path##*/}" # basename

      [ -f "${OLD_REPO_DIR}/${package}" ] \
	  && error "Package: ${package} with same version already exists in ${OLD_REPO_DIR}"
  done
  
  ## -----------------------------------------------------------------------
  ## -----------------------------------------------------------------------
  # only update index when new charts are added
  if [ ${#package_paths[@]} -gt 0 ]; then

      # Create updated index.yaml (new version created in NEW_REPO_DIR)
      helm_index_merge "${OLD_REPO_DIR}" "${NEW_REPO_DIR}"

      # move over packages and index.yaml
      mv "${NEW_REPO_DIR}"/*.tgz "${OLD_REPO_DIR}/"
      mv "${NEW_REPO_DIR}/index.yaml" "${OLD_REPO_DIR}/index.yaml"

      echo "# helmrepo.sh Success! Updated existing repo index in ${OLD_REPO_DIR}"

  else
    echo "# helmrepo.sh Success! No new charts added."
  fi
fi

exit 0