#!/bin/bash
#
# ucolour: Set urxvt (or terminal which understands the same escape sequences)
#          colours.
# Usage: ucolour option <colour> [option <colour> ...]
# Options: -b   Set background.
#          -B   Set highlight background.
#          -c   Set cursor.
#          -d   Set border.
#          -f   Set foreground.
#          -F   Set highlight foreground.
#          -m   Set mouse.
#          -P   Palette index.
#          -p   Set palette reference with -P.
# Notes: Border defaults to background.
#        The -P and -p flags must be used together.
#        Colour spec can be a simple number, to copy the
#        existing palette entry for that index. 
#

PROG=ucolour
tmux_prefix=
[ -n "$TMUX" ] && tmux_prefix="\033Ptmux;\033"

function parse_colour() {
  local arg=$1; shift
  local safe=${arg//[1-9]/}

  if [ "$safe" = "0" -o -z "$safe" ]; then
    # Hack to get existing.
    local index=$(
      local index
      exec < /dev/tty
      local oldstty=$(stty -g)
      stty raw -echo min 0
      echo -en "$tmux_prefix\033]4;$arg;?\007" > /dev/tty
      local ret=1
      local tries=0
      while [ $ret -gt 0 ]; do
        tries=$((tries+1))
        IFS='' read -t 0
        ret=$?
        if [ $tries -gt 2 ]; then
          [ $tries -gt 3 ] && break
          sleep 1
        fi
      done
      IFS='' read -r index
      stty $oldstty
      echo "$index"
    )
    if [ -n "$index" ]; then
      index=${index##*;}
      index=${index%?}
      echo "$index"
      echo >&2 "$PROG: Colour $arg is $index."
      return 0
    fi
  else
    echo "$arg"
    return 0
  fi

  echo ""
  return 1
}

BG=
FG=
bg=
bd=
fg=
cu=
mo=
pc=
ps=
while getopts ":B:F:P:b:c:d:f:m:p:" opt; do
  case $opt in
    B) BG=$(parse_colour $OPTARG);;
    F) FG=$(parse_colour $OPTARG);;
    P) pc=$OPTARG;;
    b) bg=$(parse_colour $OPTARG);;
    c) cu=$(parse_colour $OPTARG);;
    d) bd=$(parse_colour $OPTARG);;
    f) fg=$(parse_colour $OPTARG);;
    m) mo=$(parse_colour $OPTARG);;
    p) ps=$(parse_colour $OPTARG);;
  esac
done
shift $((OPTIND-1))

if [ -n "$pc" -o -n "$ps" ]; then
  if [ -z "$pc" -o -z "$ps" ]; then
    echo >&2 "$PROG: Must use -P and -p together."
    exit 1
  fi
fi
[ -n "$bg" -a -z "$bd" ] && bd=$bg
if [ -z "$BG$FG$bd$bg$cu$fg$mo$pc" ]; then
  echo >&2 "Usage: ucolour option <colour> [option <colour> ...]"
  echo >&2 "Options: -b   Set background."
  echo >&2 "         -B   Set highlight background."
  echo >&2 "         -c   Set cursor."
  echo >&2 "         -d   Set border."
  echo >&2 "         -f   Set foreground."
  echo >&2 "         -F   Set highlight foreground."
  echo >&2 "         -m   Set mouse."
  echo >&2 "         -P   Palette index."
  echo >&2 "         -p   Set palette reference with -P."
  echo >&2 "Notes: Border defaults to background."
  echo >&2 "       The -P and -p flags must be used together."
  exit 1
fi

[ -n "$BG" ] && echo -en "$tmux_prefix\033]17;$BG\007"
[ -n "$FG" ] && echo -en "$tmux_prefix\033]19;$FG\007"
[ -n "$bg" ] && echo -en "$tmux_prefix\033]11;$bg\007"
[ -n "$bd" ] && echo -en "$tmux_prefix\033]708;$bd\007"
[ -n "$cu" ] && echo -en "$tmux_prefix\033]12;$cu\007"
[ -n "$fg" ] && echo -en "$tmux_prefix\033]10;$fg\007"
[ -n "$mo" ] && echo -en "$tmux_prefix\033]13;$mo\007"
[ -n "$pc" ] && echo -en "$tmux_prefix\033]4;$pc;$ps\007"
exit 0