path: root/functions/utilities.zsh

# vim:ft=zsh ts=2 sw=2 sts=2 et fenc=utf-8
################################################################
# Utility functions
# This file holds some utility-functions for
# the powerlevel9k-ZSH-theme
# https://github.com/bhilburn/powerlevel9k
################################################################

# Usage: set_default [OPTION]... NAME [VALUE]...
#
# Options are the same as in `typeset`.
function set_default() {
  local -a flags=(-g)
  while true; do
    case $1 in
      --) shift; break;;
      -*) flags+=$1; shift;;
      *) break;
    esac
  done

  local varname=$1
  shift
  if [[ -v $varname ]]; then
    typeset $flags $varname
  elif [[ "$flags" == *[aA]* ]]; then
    eval "typeset ${(@q)flags} ${(q)varname}=(${(qq)@})"
  else
    typeset $flags $varname="$*"
  fi
}

# Converts large memory values into a human-readable unit (e.g., bytes --> GB)
# Takes two arguments:
#   * $size - The number which should be prettified
#   * $base - The base of the number (default Bytes)
printSizeHumanReadable() {
  typeset -F 2 size
  size="$1"+0.00001
  local extension
  extension=('B' 'K' 'M' 'G' 'T' 'P' 'E' 'Z' 'Y')
  local index=1

  # if the base is not Bytes
  if [[ -n $2 ]]; then
    local idx
    for idx in "${extension[@]}"; do
      if [[ "$2" == "$idx" ]]; then
        break
      fi
      index=$(( index + 1 ))
    done
  fi

  while (( (size / 1024) > 0.1 )); do
    size=$(( size / 1024 ))
    index=$(( index + 1 ))
  done

  echo "$size${extension[$index]}"
}

# Determine if the passed segment is used in the prompt
#
# Pass the name of the segment to this function to test for its presence in
# either the LEFT or RIGHT prompt arrays.
#    * $1: The segment to be tested.
segment_in_use() {
  local key=$1
  [[ -n "${POWERLEVEL9K_LEFT_PROMPT_ELEMENTS[(r)$key]}" ||
     -n "${POWERLEVEL9K_RIGHT_PROMPT_ELEMENTS[(r)$key]}" ]]
}

################################################################
# Given a directory path, truncate it according to the settings.
# Parameters:
#   * $1 Path: string - the directory path to be truncated
#   * $2 Length: integer - length to truncate to
#   * $3 Delimiter: string - the delimiter to use
#   * $4 From: string - "right" | "middle". If omited, assumes right.
function truncatePath() {
  # if the current path is not 1 character long (e.g. "/" or "~")
  if (( ${#1} > 1 )); then
    # convert $2 from string to integer
    2=$(( $2 ))
    # set $3 to "" if not defined
    [[ -z $3 ]] && 3="" || 3=$(echo -n $3)
    # set $4 to "right" if not defined
    [[ -z $4 ]] && 4="right"
    # create a variable for the truncated path.
    local trunc_path
    # if the path is in the home folder, add "~/" to the start otherwise "/"
    [[ $1 == "~"* ]] && trunc_path='~/' || trunc_path='/'
    # split the path into an array using "/" as the delimiter
    local paths=$1
    paths=(${(s:/:)${paths//"~\/"/}})
    # declare locals for the directory being tested and its length
    local test_dir test_dir_length
    # do the needed truncation
    case $4 in
      right)
        # include the delimiter length in the threshhold
        local threshhold=$(( $2 + ${#3} ))
        # loop through the paths
        for (( i=1; i<${#paths}; i++ )); do
          # get the current directory value
          test_dir=$paths[$i]
          test_dir_length=${#test_dir}
          # only truncate if the resulting truncation will be shorter than
          # the truncation + delimiter length and at least 3 characters
          if (( $test_dir_length > $threshhold )) && (( $test_dir_length > 3 )); then
            # use the first $2 characters and the delimiter
            trunc_path+="${test_dir:0:$2}$3/"
          else
            # use the full path
            trunc_path+="${test_dir}/"
          fi
        done
      ;;
      middle)
        # we need double the length for start and end truncation + delimiter length
        local threshhold=$(( $2 * 2 ))
        # create a variable for the start of the end truncation
        local last_pos
        # loop through the paths
        for (( i=1; i<${#paths}; i++ )); do
          # get the current directory value
          test_dir=$paths[$i]
          test_dir_length=${#test_dir}
          # only truncate if the resulting truncation will be shorter than
          # the truncation + delimiter length
          if (( $test_dir_length > $threshhold )); then
            # use the first $2 characters, the delimiter and the last $2 characters
            last_pos=$(( $test_dir_length - $2 ))
            trunc_path+="${test_dir:0:$2}$3${test_dir:$last_pos:$test_dir_length}/"
          else
            # use the full path
            trunc_path+="${test_dir}/"
          fi
        done
      ;;
    esac
    # return the truncated path + the current directory
    echo $trunc_path${1:t}
  else # current path is 1 character long (e.g. "/" or "~")
    echo $1
  fi
}

# Search recursively in parent folders for given file.
function upsearch () {
  if [[ "$PWD" == "$HOME" || "$PWD" == "/" ]]; then
    echo "$PWD"
  elif test -e "$1"; then
    pushd .. > /dev/null
    upsearch "$1"
    popd > /dev/null
    echo "$PWD"
  else
    pushd .. > /dev/null
    upsearch "$1"
    popd > /dev/null
  fi
}

# Parse IP address from ifconfig on OSX and from IP on Linux
# Parameters:
#  $1 - string The desired Interface
#  $2 - string A root prefix for testing purposes
function p9k::parseIp() {
  local desiredInterface="${1}"

  if [[ -z "${desiredInterface}" ]]; then
    desiredInterface="^[^ ]+"
  fi

  local ROOT_PREFIX="${2}"
  if [[ "$OS" == "OSX" ]]; then
    # Get a plain list of all interfaces
    local rawInterfaces="$(${ROOT_PREFIX}/sbin/ifconfig -l 2>/dev/null)"
    # Parse into array (split by whitespace)
    local -a interfaces
    interfaces=(${=rawInterfaces})
    # Parse only relevant interface names
    local pattern="${desiredInterface}[^ ]?"
    local -a relevantInterfaces
    for rawInterface in $interfaces; do
      [[ "$rawInterface" =~ $pattern ]] && relevantInterfaces+=( $MATCH )
    done
    local newline=$'\n'
    for interfaceName in $relevantInterfaces; do
      local interface="$(${ROOT_PREFIX}/sbin/ifconfig $interfaceName 2>/dev/null)"
      if [[ "${interface}" =~ "lo[0-9]*" ]]; then
        continue
      fi
      # Check if interface is UP.
      if [[ "${interface//${newline}/}" =~ "<([^>]*)>(.*)inet[ ]+([^ ]*)" ]]; then
        local ipFound="${match[3]}"
        local -a interfaceStates=(${(s:,:)match[1]})
        if [[ "${interfaceStates[(r)UP]}" == "UP" ]]; then
          echo "${ipFound}"
          return 0
        fi
      fi
    done
  else
    local -a interfaces
    interfaces=( "${(f)$(${ROOT_PREFIX}/sbin/ip -brief -4 a show 2>/dev/null)}" )
    local pattern="^${desiredInterface}[ ]+UP[ ]+([^/ ]+)"
    for interface in "${(@)interfaces}"; do
      if [[ "$interface" =~ $pattern ]]; then
        echo "${match[1]}"
        return 0
      fi
    done
  fi

  return 1
}