#!/bin/sh
#
# text2img_fixed [options] output_image  < textfile
#
# Given a text file of characters (utf-8) convert each character into
# an image, and join them together into a table of 'fixed width' character
# cells.  That is convert the text keeping the results tabular as if using a
# 'monospace' font, even if the font used is proportional.
#
# Options:
#    -font {im_font}      Font to use to 'draw the characters
#    -pointsize {points}  Pointsize of characters
#    -box {color}         Use this colored undercolor box
#    -line                Characters per line (Max) (default = 70)
#
# Examples
#   echo 'This is a \ @ # ? test! . ' | text2img_fixed x:
#   graphics_utf -n | text2img_fixed -font Dingbats -line 16 x:
#
# Known Problem...
#   As each character is trimmed, the character is centered in the final
# string!  The trim was added to prevent very large proportional space
# characters making the resulting line overly long.  A better method is
# needed, prehaps just a 'horizontal trim'   Can you improve this script?
#
####
#
# WARNING: Input arguments are NOT tested for correctness.
# This script represents a security risk if used ONLINE.
# I accept no responsiblity for misuse. Use at own risk.
#
# Anthony Thyssen    December 2006
#
PROGNAME=`type $0 | awk '{print $3}'`  # search for executable on path
PROGDIR=`dirname $PROGNAME`            # extract directory of program
PROGNAME=`basename $PROGNAME`          # base name of program
Usage() {                              # output the script comments as docs
  echo >&2 "$PROGNAME:" "$@"
  sed >&2 -n '/^###/q; /^#/!q; s/^#//; s/^ //; 3s/^/Usage: /; 2,$ p' \
          "$PROGDIR/$PROGNAME"
  exit 10;
} 

# defaults
font=arial
pointsize=18
box=white      # undercolor box white will dissappear into background
line=70        # default line length for output.

while [ $# -gt 0 ]; do
  case "$1" in
  --help|--doc*) Usage ;;
  -font)      shift; font="$1" ;;        # font to use
  -f)         shift; font="$1" ;;        # font to use
  -pointsize) shift; pointsize="$1" ;;   # character size
  -p)         shift; pointsize="$1" ;;   # character size
  -box)       shift; box="$1" ;;         # undercolor box color
  -line)      shift; line="$1" ;;
  -l)         shift; line="$1" ;;

  --) shift; break ;;    # end of user options
  -*) Usage "Unknown option \"$1\"" ;;
  *)  break ;;           # end of user options

  esac
  shift   # next option
done

[ $# -lt 1 ] && Usage "Missing output image Argument"
[ $# -gt 1 ] && Usage "Too many arguments."

output="$1"

# use a locale
LC_CTYPE=en_AU.utf8
export LC_CTYPE

#------------------------------------------------------------------------------

# use perl to read in a line (as unicode), and convert each character
# to the special 'fixed width' format, as a IM command.
#
perl -e '
  $line='"'$line'"';
  $quote=chr(0x27);
  binmode(STDIN,  ":utf8");
  binmode(STDOUT, ":utf8");

  # Output a character string.
  # I use a file input so as to avoid problems such as
  #    * with handling a string starting with "@"
  #    * backslashes
  # This currently needs some method of horizontal only trim
  sub output_string {
    $s = shift;
    print "convert -quiet -font '"'$font'"' -pointsize '"'$pointsize'"' ";
    print "label:$s -set label \"\" -trim +repage miff:-;\n";
  }

  # Handle various characters special to Shell or IM
  # character is wrapped into single quotes for the "echo" command above
  sub output_char {
    output_string $quote . pack("U", shift) . $quote;
  }
  sub blank  { print "convert xc: miff:-;\n"; }    # empty character
  sub quote  { output_string "\"$quote\""; }       # quote the single quote
  sub at     { output_string $quote."\\\@".$quote; }  # excape the at symbol
  sub bslash { output_string $quote."\\\\".$quote; } # excape the backslash

  while(<>) {
    $i=0;
    foreach $c ( unpack("U*", $_ ) ) {
      $i++; last if $i > $line;
      if( $c <  0x0020 ) { next; }         # skip control characters
     #if( $c == 0x0020 ) { blank; next; }  # substitute space (doesnt trim)
      if( $c == 0x0027 ) { quote; next; }  # substutite single quote
      if( $c == 0x0040 ) { at; next; }     # escape the "@"
      if( $c == 0x005C ) { bslash; next; } # escape the "\"
     #if( $c == 0x00A0 ) { blank; next; }  # meta-space - substitute space
      output_char($c);
    }
    for( ; $i <= $line ; $i++ ) {
      blank;
    }
  }
' |
#cat; exit
sh |
#identify miff:-; exit 0
montage miff:- -tile "$line"x -geometry +2+2 \
        -bordercolor white "$output"