#!/bin/sh
#
# This program 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.
#
# This program 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 this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
# or email the author of this code for a copy.
#
# Based on the barchart script by Graham J Williams of Togaware, but 
# largely rewritten.
#
# Copyright (c) 2006 Peter Chubb

# Defaults
#
typeout=x11
ymin=0
heading=1
noxlabel=0
noylabel=0

# This section converted to /bin/sh, but otherwise verbatim from Graham's
# version:
shortmsg ()
{
  echo >&2 "Try \`$0 --help' for more information.\n"
}

usage ()
{
  echo >&2 "Usage: $0 [options] datafile [datafile] > plot.pdf

  -h, --help                    Usage plus extra help
  -t, --trend                   Draw bezier trend line
  -s, --font-size=N             Font size (points) *not all output types*
  -T, --type=[pdf,eps,fig,png]	Output type to generate
  -v, --values                  Include y values with corresponding bar
  -m, --maxy=value		The y axis maximum value
      --auto-miny               Choose min y value from data (0 otherwise)
  -n, --no-heading              Do not include a heading
  -r, --rotate                  Rotate the x axis labels
  -l, --line-at=N               Draw a line parallel to x axis at N
  -g, --log=A                   Use log scale on axis A (x or y or xy)
      --noxlabel,--noylabel     No labels on the x or y axis
" 
}

help ()
{
    cat >&2 <<\EOF
Generates a bar chart of the supplied data. The first line of the
(first) data file is the plot title. The second line contains column
titles (with _ converted to space). The remaining lines contain the x
axis label and the y value on each line, space separated.  Output is 
written to standard out.

If labels or any other entity is poorly placed then generate FIG using
\`-T fig' and modify with xfig then export to PDF.

Sample input file:
  DC 23: Eye and Ear Diseases Aggregate
  Financial_Year Total_Cost
  94/95 12340
  95/96 52.35
  96/97 311361.8
  97/98 450102.8

EOF
}  

#
# Handle command line: getopt reads the command line, checks for errors
# then generates a reformatted, reordered and well formed command line.
# Thus the user can make the command line as ugly as they like :-)
#
command_line=`getopt --options S:s:fg:hl:m:nrtT:v \
    --longoptions scale:,font-size:,force,log:,help,line-at:,maxy:,auto-miny,no-heading,rotate,trend,type,values:,noxlabel,noylabel,noxticlabels,noyticlables \
 --alternative --name "$0" -- "$@"`

if [ $? -gt 0 ] ; then
    usage
    exit 1
fi

#
# Replace old command line with newly parsed command line
#
eval set -- "$command_line"

#
# Now process all arguments
# Note: not all implemented yet.
#
while true ; do
    case "$1" in
	-s|--font-size) font_points="$2" ; shift 2;; 
	-S|--scale)     scale="$2"; shift 2;;
#	-d|--decimals)  decimals="$2" ; shift 2 ;;
	-h|--help) 	usage ; help ; exit 0 ;;
	-f|--force)	force=1 ; shift ;;
	-g|--log)       logscale="$2" ; shift 2 ;;
	-l|--line-at)   lineat="f(x)=$2,f(x) notitle," ; shift 2 ;;
	-m|--maxy)	ymax="$2" ; shift 2 ;;
	--auto-miny)	ymin="" ; shift ;;
	-n|--no-heading) heading=0 ; shift ;; 
	--noxlabel)     noxlabel=1 ; shift ;;
	--noylabel)     noylabel=1 ; shift ;;
	-r|--rotate)    xticsopts="rotate" ; xlabelshift="0,-2" ; shift ;;
	-t|--trend)	trend_line=1 ; shift ;;
        -T|--type)	typeout="$2" ; shift 2 ;;
	-v|--values)	display_values=1 ; shift ;;
	--) 		shift ; break ;;
	*) 		echo "$0: Internal error 1!" ; exit 1 ;;
    esac
done

# From here down is new.
#
# Check supplied arguments
#
case "$typeout" in 
    x11) terminal="x11"
	[ "$font_points" ] && terminal="$terminal font \"Helvetica,$font_points\""
         extra="-persist"
	 ;;
    eps)
         terminal="postscript enhanced color"
	[ "$font_points" ] && terminal="$terminal \"Helvetica\" $font_points"
	 ;;
    fig)
        terminal="fig color"
	[ "$font_points" ] && terminal="$terminal fontsize $font_points"
	;;
    pdf)
        terminal="pdf enhanced"
	[ "$font_points" ] && terminal="$terminal fsize $font_points"
	;;
    png)
       terminal="png"
	[ "$font_points" ] && terminal="$terminal font helvetica $font_points"
       ;;
    *)
    echo >&2 "$0: allowed types are [x11,pdf,eps,fig,png], not: ${typeout}\n"
    shortmsg
    exit 1
    ;;
esac

awk -v ymax="$ymax" -v ymin="$ymin" \
    -v add_heading=$heading \
    -v noxlabel=$noxlabel -v noylabel=$noylabel \
    -v trend=$trend_line -v add_values=${display_values:0} \
    -v "line=$lineat" -v scale="$scale" \
    -v "terminal=$terminal" -v lineat="$lineat" \
    -v logscale=$logscale '

#
# Given nf data files,
# What is the offset of the x values for the nth one?
# Shift by from x-0.25 to x+0.25
#
function calc_offset(n, nf)
{
	if (nf == 1)
		return 0;
	return (n-1)/(2*(nf-1)) - 0.25;
}

BEGIN {count = 1
    # guard against non-numeric scale
    if (scale+0 == 0) {
	    print "Bad scale " scale ", resetting to 1" >/dev/stderr
	    scale=1
    }
}

FILENAME != oldfilename {
	oldfilename = FILENAME;
	nf++;
	filenames[nf] = FILENAME;
}

FNR==1 { 
	split($0, a);
	# Merge titles from each file
	if (title[1] == "")
		split($0, title);
	else  {
		for (i = 1; title[i] != ""; i++) {
			if (a[i] != title[i])
				break;
		}
		for (j = i+1; title[j] != ""; j++)
			;
		for (k=1 ; a[i] != ""; i++) {
			title[j++] = a[i];
			name[nf] = name[nf] " " a[i]
		}			
	}
}

FNR==2 && $1 != "" && $2 != "" { 
	xlabel[nf]=$1; ylabel[nf]=$2; 
}

FNR > 2 { # At last.. a data point.
        if (!($1 in idx)) {
		labels[count] = $1;
		idx[$1] = count++;
	}
	$2 *= scale;
	values[idx[$1], nf] = $2;
	if ($2 > max)
		max = $2;
}

END {
	boxwidth = nf > 1 ? 0.25 : 0.5;


	if (add_heading) {
		printf "set title \""
		for (i = 1; i <= length(title); i++)
			printf "%s ", title[i];
		printf "\"\n"
	}

	print "set terminal " terminal

       if (logscale != "") {
	       ymin=""
	       print "set logscale y"
       }
	
	print "set xrange [0:" count+1 "]"
	if (ymax == "")
	    ymax = max;
	print "set yrange [" ymin ":"  ymax "]"
	print "set grid noxtics ytics"
	print "set style fill solid"
	print "set boxwidth " boxwidth " relative"

	if (!force_labels)
	    for (i = 2; i <= nf; i++) {
		    if (xlabel[i] != xlabel[1]) {
			    print "Xlabels don'"'"'t match in files " i" and 1" > "/dev/stderr"
			    exit(1);
			}
		    if (ylabel[i] != ylabel[1]) {
			    print "Ylabels don'"'"'t match in files " i" and 1" > "/dev/stderr"
			    exit(1);
		    }
	}

	if (!noxlabel)
	    print "set xlabel \"" xlabel[1] "\""
	if (!noylabel)
	    print "set ylabel \"" ylabel[1] "\""

	#
	# Set up the X-axis labels
	#
	printf "set xtics ("
	between=""
	for (i = 1; i < count; i++) {
		printf "%s \"%s\" %d", between, labels[i], i;
		between = ","
	}
	print ")"

	# 
	# Add the values at the top of each bar.
	#
        if (add_values)
		for (i = 1; i <= nf; i++) {
		    offset=calc_offset(i, nf);
		    for (j=1; j < count; j++)
			    printf "set label \"%g\" at %g,%g center\n", values[j, i], j+offset, values[j,i];
		}

	#
	# And finally the plot commands themselves.
	#
	printf "plot " lineat
	for (i = 1; i <= nf; i++) {
		if (name[i] == "")
			name[i] = filenames[i];
		printf " \"-\" title \"" name[i] "\"  with boxes";
		if (i < nf || trend)
		    printf ", "
	}
	if (trend)
	    for (i = 1; i <= nf; i++) {
		printf " \"-\" smooth bezier notitle";
		if (i < nf)
		    printf ", "
	}
        printf "\n"

	# And the data.
	# Order is the same as that in the first data file.
        #
	for (i=1; i <= nf; i++) {
	       offset=calc_offset(i, nf)
	       for (j = 1; j < count; j++)
		   print j + offset, values[j, i];
	       print "e"
	}
	if (trend)
	    for (i=1; i <= nf; i++) {
		offset=calc_offset(i, nf)
		for (j = 1; j < count; j++)
			print j + offset, values[j, i];
		print "e"
	    }

}' "$@"  | gnuplot $extra