functions

################################################################################
#      This file is part of LibreELEC - http://www.libreelec.tv
#      Copyright (C) 2016 Neil MacLeod ([email protected])
#
#  LibreELEC is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 2 of the License, or
#  (at your option) any later version.
#
#  LibreELEC is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with LibreELEC.  If not, see <http://www.gnu.org/licenses/>.
################################################################################

# Need a read/write location, as tmp may not always be available
mkdir -p /dev/.progress
rm -f /dev/.progress/*

# Show frame-buffer cursor
showcursor() {
  echo -en "\033[?25h"

  # show cursor
  if [ -f /sys/devices/virtual/graphics/fbcon/cursor_blink ] ; then
    echo 1 > /sys/devices/virtual/graphics/fbcon/cursor_blink
  fi
}

# Hide frame-buffer cursor
hidecursor() {
  echo -en "\033[?25l"

  if [ -f /sys/devices/virtual/graphics/fbcon/cursor_blink ] ; then
    echo 0 > /sys/devices/virtual/graphics/fbcon/cursor_blink
  fi
}

# Start a progress meter
# $1: spinner, percent, countdown
# $2: message to display
# [spinner]
#   $3: optional command to execute
#   $4: optional success completion message (nothing if not specified)
#   $5: optional failure completion message ($4 if not specified)
# [percent]
#   $3: name of filename to be progress monitored
#   $4: terminal size (in bytes) of $3 when progress is complete
#   $5: optional command to execute
#   $6: optional success message (100% if not specified)
#   $7: optional failure message ($6 if not specified)
# [countdown]
#   $3: number of seconds to start counting down from
#   $4: optional completion message, default is nothing
StartProgress() {
  local cmdresult=0

  # Use files for inter-process communication.
  # This file is used to indicate a metter is running/active

  echo > /dev/.progress/run

  case "$1" in
    spinner)
      ProgressTask_Spinner "$2" &
      if [ -n "$3" ]; then
        eval "$3"
        cmdresult=$?
        [ $cmdresult -eq 0 ] && StopProgress "${4}" || StopProgress "${5:-$4}"
      fi
      ;;
    percent)
      ProgressTask_Percent "$2" "$3" $4 &
      if [ -n "$5" ]; then
        eval "$5"
        cmdresult=$?
        [ $cmdresult -eq 0 ] && StopProgress "${6}" || StopProgress "${7:-$6}"
      fi
      ;;
    countdown)
      ProgressTask_Countdown "$2" $3 "$4"
      ;;
    *)
      echo "Unknown spinner type: $1"
      return 1
      ;;
  esac

  return $cmdresult
}

# Stop a progress meter, displaying optional completion message
# $1: optional completion message (appropriate default used if not specified)
StopProgress() {
  # Instruct running progress meter to end, showing specified completion message
  echo "${1}" > /dev/.progress/stop

  # Wait for progress meter to stop running
  while [ -f /dev/.progress/run ]; do
    usleep 250000
  done

  # Clean up
  rm -f /dev/.progress/stop
  return 0
}

# Use this task for processes of indeterminate duration
ProgressTask_Spinner() {
  local msg="$1"
  local spinner="|/-\\|/-\\"
  local count=0 donemsg

  echo -n "${msg} "

  while [ ! -f /dev/.progress/stop ]; do
    echo -en "\b${spinner:$count:1}"
    usleep 500000
    count=$(((count + 1) % 8))
  done

  donemsg="$(cat /dev/.progress/stop)"
  echo -e "\b${donemsg:-done}"

  rm -f /dev/.progress/run

  exit 0
}

# Use this task when transferring a file of known size
ProgressTask_Percent() {
  local msg="$1" filename="$2" fsize=$3 csize donemsg

  echo -n "${msg}    "

  while [ ! -f /dev/.progress/stop ]; do
    [ -f ${filename} ] && csize=$(stat -t "${filename}" | awk '{print $2}') || csize=0
    echo $csize $fsize | awk '{ printf "\b\b\b\b%3d%%", ($1 * 100 / $2) }'
    usleep 250000
  done

  donemsg="$(cat /dev/.progress/stop)"
  echo -e "\b\b\b\b${donemsg:-100%}"

  rm -f /dev/.progress/run

  exit 0
}

# Use this task to countdown a number of seconds
# (needs more work for durations > 99 seconds)
ProgressTask_Countdown() {
  local msg="$1" countfrom=$2 donemsg="$3"

  echo -n "${msg}  "

  while [ ${countfrom} -gt 0 ]; do
    echo ${countfrom} | awk '{ printf "\b\b%2d", $1 }'
    sleep 1
    countfrom=$((countfrom - 1))
  done

  echo -e "\b\b${donemsg:-  }"

  rm -f /dev/.progress/run

  return 0
}