#!/bin/sh

# Boilerplate
_root="$(dirname "${0}")"; . "${_root}/lib/env.sh"

# Load needed modules
want ansi log progress
printf "${a_normal}"

pebkac() {
  echo "Insert help here"
}

# Parse command line options
while getopts "n:h" opt
do
  case "${opt}" in
    n) name="${OPTARG}" ;;
    h) pebkac ;;
    [?]) pebkac "Unrecognized option ${opt}" ;;
  esac
done
shift $(( $OPTIND - 1 ))

src="${1}"
out="${2}"

[ -r "${src}" ] || err "${src}: no such file or directory"
[ ! -f "${out}" ] || err "${out}: file exists"

# mkisofs switch meanings
# -v            Verbose
# -gui          GUI-suitable status messages
# -D            No deep directory relocation (and no RR_MOVED)
# -R            Include rock-ridge extensions
# -no-pad       Don't pad to 150 sectors
# -iso-level 4  iso8859:1999 standard
# -p CyberLeo   Set preparer string
# -V <volname>  Set volume label
# -o splat      output filename
command="/usr/local/bin/mkisofs -v -gui -D -R -no-pad -iso-level 4 -p CyberLeo -V '${name}' -o '${out}' '${src}' 2>&1"

time_start="$(date +%s)"

eval ${command} | sed -l -e '/^Writing: *The File(s).*$/s/^.*$/started=1 total=10000/; s/^\([ 0-9.%]*\) done.*$/count=\1/; /^[0-9]* extents written/s/^.*$/finished=1/; /=/!d; /^count=/s/[ .%]//g' | while read line
do
  # initialization
  count="${count:-0}"

  # Read in values
  eval ${line}

  # Compute aggregates
  iter="$(( ${iter:-0} + 1 ))"
  
  if [ -n "${finished}" -o "$(( ${iter} % ${limit_break:-16} ))" -eq 0 ] && \
    [ -n "${finished}" -o "$(date +%s)" != "${time_last}" ]
  then
    time="$(date +%s)"
    
    iter_diff="$(( ${iter:-0} - ${iter_last:-0} ))"
    time_diff="$(( ${time} - ${time_last:-0} ))"
    
    # Adjust last iteration length as a rolling average of half the last per-second cluster count
    [ -z "${finished}" ] && limit_break="$(( ( ${limit_break:-16} + ( ( ${iter_diff} / ${time_diff} ) / 2 ) ) / 2 ))"
    [ "${limit_break}" -eq 0 ] && limit_break=1 # Avoid divide-by-zero errors

    iter_last="${iter:-0}"
    time_last="${time}"

    [ -n "${finished}" ] && count="${total}"

    printf "\r %s\033[K" "$(progress "${count}" "${total}")"

    [ -n "${finished}" ] && printf "\n"
  fi
done