#!/bin/sh 
#
#       @(#)plotcurves 1997/02/13 Anne Bennett
#
# Use gnuplot to print graphs of the data of interest,
# i.e. principal remaining to pay on mortgage, actual and 
# projected.
#
# If an argument is given, it is assumed to be the name of
# the output file; if no argument, graph should be plotted
# to the terminal.
#
# Mortgage data will be found in files whose format is
#     728854 19950715 10577535  blah blah
#     date-1 date-2   amount-1  label
# where
#  date-1 = date in days-since-epoch
#  date-2 = human-usable date in YYYYMMDD
#  amount-1 = amount of capital remaining to pay, in cents
#  label  = optional field(s) to identify curve.

thisprog=mortgage-plotcurves
PATH=/local/bin:/anne/accounting/bin:/bin:/usr/bin
export PATH

# Directory containing files of data
datadir=/anne/accounting/mortgage/data
# Prefix name of files containing data to be plotted:
prefix=curve.

# Path to gnuplot
gnuplot=`which gnuplot`

# Path to ndate
ndate=`which ndate`

# Need a tmp file for gnuplot commands:
cmd_file=/tmp/mortgage-plotcurves-cmd.$$
# And a bunch of tmp files for massaged data:
tmp_prefix=/tmp/mortgage-plotcurves-tmp.$$


# ============== Parse arguments

if   [ $# -eq 1 ]; then
    to_file=yes
    ps_file="$1"
    echo "${thisprog}: sending output to file '${ps_file}'."
elif [ $# -eq 0 ]; then
    to_file=no
else
    echo "usage: ${thisprog} [outfile]"
    exit 1
fi

# Go to directory with files to be graphed.
cd ${datadir}

# Make list of those files
files="${prefix}*"


# ============== Build the command file for gnuplot, preface.

# General settings to send output to PostScript file
# (if appropriate) and to graph with lines.

touch     ${cmd_file}
chmod 755 ${cmd_file}
echo >> ${cmd_file}  '#!'${gnuplot}
echo >> ${cmd_file}  '#'
echo >> ${cmd_file}  '# Automatically generated by '${thisprog}' on '`date`
echo >> ${cmd_file}  ''
if [ "${to_file}" = "yes" ]; then
   echo >> ${cmd_file}  'set terminal postscript'
   echo >> ${cmd_file}  'set output "'${ps_file}'"'
fi
echo >> ${cmd_file}  'set data style lines'
#echo >> ${cmd_file}  'set grid'
echo >> ${cmd_file}  ''
echo >> ${cmd_file}  ''

# Graph title
echo    >> ${cmd_file}  'set title "Mortgage repayment, actual and predicted"'


# ============== Build the command file for gnuplot, data and curve labels.

fnames=""
for f in ${files} ; do
   # massage the data to keep only days-since-epoch date 
   # and convert amount to dollars; also, keep the *last*
   # "label" field found in each file, and use it for the
   # curve identifier.
   filename=`echo ${f} | tr -dc '[A-Za-z0-9]'`
   fnames="${fnames} ${filename}"
   < ${f} awk '
                  {
                  printf("%d  %.2f\n", $1 , $3 / 100 );
                  }
             ' >> ${tmp_prefix}.${filename}
   < ${f}  awk '
                  BEGIN { label="original" }
                  { if ( NF > 3 ) {
                      $1 = "";
                      $2 = "";
                      $3 = "";
                      label=$0;
                    }
                  }
                  END { printf("%s",label) }
             ' >> ${tmp_prefix}.${filename}.label
done


# ============== Build the command file for gnuplot, axes and ranges.

# Figure out x (time) minimum and maximum, and y (amount) maximum (in dollars).
set `cat ${files} | awk '
   BEGIN { xmin=10000000;
           xmax=0;
           ymax=0;
         }
         { if ($1 < xmin) { xmin=$1 };
           if ($1 > xmax) { xmax=$1 };
           if ($3 > ymax) { ymax=$3 };
         }
     END { printf("%.0f  %.0f  %.0f", xmin, xmax, ymax/100);
         }
'`
xmin=$1
xmax=$2
ymax=$3

# Set graph ranges in consequence:
echo >> ${cmd_file} 'set xrange ['${xmin}':'${xmax}']'
echo >> ${cmd_file} 'set yrange ['0':'${ymax}']'


# Graph axes:  TRY TO MAKE THIS MORE GENERAL
now=`${ndate} -eo`
cat >> ${cmd_file} <<'HERE'
set format y "%.0f"
set ytics 0,10000,150000
set xtics (           \
    "1995" 728840 ,   \
    ""     729206 ,   \
    ""     729571 ,   \
    ""     729936 ,   \
    ""     730301 ,   \
    "2000" 730667 ,   \
    ""     731032 ,   \
    ""     731397 ,   \
    ""     731762 ,   \
    ""     732128 ,   \
    "2005" 732493 ,   \
    ""     732858 ,   \
    ""     733223 ,   \
    ""     733589 ,   \
    ""     733954 ,   \
    "2010" 734319 ,   \
    ""     734684 ,   \
    ""     735050 ,   \
    ""     735415 ,   \
    ""     735780 ,   \
    "2015" 736145 ,   \
    ""     736511 ,   \
    ""     736876 ,   \
    ""     737241 ,   \
    ""     737606 ,   \
    "2020" 737972 ,   \
HERE
cat >> ${cmd_file} <<HERE
    "*"    ${now} )
HERE


# ============== Build the command file for gnuplot, plot commands.

# commands to plot the massaged data with its labels
echo    >> ${cmd_file} ''
echo -n >> ${cmd_file} 'plot '
first="yes"
for f in ${fnames} ; do
   if [ "${first}" = "no" ]; then
      echo    >> ${cmd_file} ', \'
      echo -n >> ${cmd_file} '     '
   else
      first=no
   fi
   echo -n >> ${cmd_file}  '"'${tmp_prefix}.${f}'" using 1:2 '
   echo -n >> ${cmd_file}  'title "'
   cat     >> ${cmd_file}  ${tmp_prefix}.${f}.label
   echo -n >> ${cmd_file}  '"'
done


echo    >> ${cmd_file} ''
echo    >> ${cmd_file} ''

# Pause to display result if we're using a terminal
if [ "${to_file}" = "no" ]; then
   echo >> ${cmd_file}  'pause -1 "Press <CR> to dismiss plot."'
fi

# Now that the command file is ready, execute it:
${cmd_file} 

#rm -f ${cmd_file}
rm -f ${tmp_prefix}*