#!/bin/sh

# shellcheck source=../lib/load-configuration
. "${0%/*}/../lib/load-configuration"

# shellcheck disable=SC2016
usage() {
  >&2 echo ''
  >&2 echo 'manage-slaves $action [parameters]: manage the list of build slaves'
  >&2 echo ''
  >&2 echo 'possible actions:'
  >&2 echo '  add $name $owner $ssh-key-fingerprint'
  >&2 echo '  disable $name'
  >&2 echo '  enable $name'
  exit 1
}

if [ $# -eq 0 ]; then
  usage
fi

if errors=$(
  printf '%s\n' "$@" | \
    grep -vx '[-0-9a-zA-Z=+/]\+'
); then
  >&2 echo 'The following parameters contain invalid characters:'
  printf '%s\n' "${errors}" | \
    sed '
      s/^/"/
      s/$/"/
    ' >&2
  usage
fi

case "$1" in
  'add')
    shift
    if [ $# -ne 3 ]; then
      >&2 printf '"add" expects 3 parameters, %s were given\n' "$#"
      usage
    fi
    person_id=$(
      # shellcheck disable=SC2016
      {
        printf 'SELECT `persons`.`id`'
        printf ' FROM `persons`'
        printf ' WHERE `persons`.`name`="%s"' \
          "${2}"
      } | \
        mysql_run_query
    )
    if [ -z "${person_id}" ]; then
      >&2 printf 'Cannot find person "%s" in the database.\n' \
        "${2}"
      usage
    fi
    duplicate=$(
      # shellcheck disable=SC2016
      {
        printf 'SELECT CONCAT('
          printf '"ssh-key: ",'
          printf '`ssh_keys`.`fingerprint`'
        printf ')'
        printf ' FROM `ssh_keys`'
        printf ' WHERE `ssh_keys`.`fingerprint`="%s";\n' \
          "${3}"
        printf 'SELECT CONCAT('
          printf '"build-slave: ",'
          printf '`build_slaves`.`name`'
        printf ')'
        printf ' FROM `build_slaves`'
        printf ' WHERE `build_slaves`.`name`="%s";\n' \
          "${1}"
      } | \
        mysql_run_query
    )
    if [ -n "${duplicate}" ]; then
      >&2 printf 'Some entry already existed in the database:\n%s\n' \
        "${duplicate}"
      usage
    fi
    # shellcheck disable=SC2016
    {
      printf 'INSERT INTO `ssh_keys`(`owner`,`fingerprint`)'
      printf ' VALUES'
      printf ' (%s,"%s");\n' \
        "${person_id}" \
        "${3}"
      printf 'INSERT INTO `build_slaves`('
        printf '`name`,'
        printf '`ssh_key`,'
        printf '`is_sane`,'
        printf '`access_allowed`'
      printf ') VALUES'
      printf '("%s",LAST_INSERT_ID(),1,1);\n' \
        "${1}"
    } | \
      mysql_run_query
    printf 'command="%s/bin/slave-build-connect %s" ssh-rsa %s %s@%s\n' \
      "${base_dir}" \
      "${1}" \
      "${3}" \
      "${2}" \
      "${1}" >> \
      ~/".ssh/authorized_keys"
  ;;
  'disable'|'enable')
    action="${1}"
    shift
    if [ $# -ne 1 ]; then
      >&2 printf '"%s" expects one parameter, %s were given\n' \
        "${action}" \
        "$#"
      usage
    fi
    infos=$(
      # shellcheck disable=SC2016
      {
        printf 'SELECT'
        printf ' `build_slaves`.`id`,'
        printf 'CONCAT('
          printf '"command=\\\"%s/bin/slave-build-connect ",' \
            "${base_dir}"
          printf '`build_slaves`.`name`,'
          printf '"\\\" ssh-rsa ",'
          printf '`ssh_keys`.`fingerprint`,'
          printf '" ",'
          printf '`persons`.`name`,'
          printf '"@",'
          printf '`build_slaves`.`name`'
        printf ')'
        printf ' FROM `build_slaves`'
        mysql_join_build_slaves_ssh_keys
        mysql_join_ssh_keys_persons
        printf ' WHERE `build_slaves`.`name`="%s"' \
          "${1}"
        printf ' AND `build_slaves`.`access_allowed`='
        if [ "${action}" = 'disable' ]; then
          printf 1
        else
          printf 0
        fi
        printf ';\n'
      } | \
        mysql_run_query | \
        tr '\t' ' '
    )
    if [ -z "${infos}" ]; then
      >&2 printf 'Cannot find build slave "%s" in the database to %s.\n' \
        "${1}" \
        "${action}"
      usage
    fi
    if [ "${action}" = 'disable' ]; then
      grep -vF "$(
        printf '%s\n' "${infos}" | \
          sed '
            s/^\S\+ //
            s/\s\+\S\+$//
          '
      )" ~/".ssh/authorized_keys" | \
        sponge ~/".ssh/authorized_keys"
    else
      printf '%s\n' "${infos}" | \
        sed 's/^\S\+ //' >> \
        ~/".ssh/authorized_keys"
    fi
    # shellcheck disable=SC2016
    {
      printf 'UPDATE `build_slaves`'
      printf ' SET `build_slaves`.`access_allowed`='
      if [ "${action}" = 'disable' ]; then
        printf 0
      else
        printf 1
      fi
      printf ' WHERE `build_slaves`.`id`=%s;\n' \
        "${infos%% *}"
    } | \
      mysql_run_query
  ;;
  *)
    >&2 printf 'unknown action "%s"\n' "$1"
    usage
  ;;
esac