#!/usr/bin/env python

############################################################################
#
# MODULE:       i.spectral
# AUTHOR(S):    Markus Neteler, 18. August 1998
#               Converted to Python by Glynn Clements
# PURPOSE:      displays spectral response at user specified locations in group or images
# COPYRIGHT:    (C) 1999 by the GRASS Development Team
#
#               This program is free software under the GNU General Public
#               License (>=v2). Read the file COPYING that comes with GRASS
#               for details.
#
#############################################################################

# written by Markus Neteler 18. August 1998
#            neteler geog.uni-hannover.de
# 
# bugfix: 25. Nov.98/20. Jan. 1999
# 3 March 2006: Added multiple images and group support by Francesco Pirotti - CIRGEO
# this script needs gnuplot

#%Module
#%  description: Displays spectral response at user specified locations in group or images.
#%  keywords: imagery
#%  keywords: raster
#%  keywords: multispectral
#%End
#%option G_OPT_I_GROUP
#% required : no
#%end
#%option G_OPT_R_INPUTS
#% key: raster
#% required : no
#%end
#%option G_OPT_F_OUTPUT
#% key: output
#% description: Name for output PNG image
#% required : no
#%end
#%option G_OPT_M_EN
#% required : yes
#%end
#%flag 
#%key: c
#%description: Label with coordinates instead of numbering
#%end
#%flag 
#%key: g
#%description: Use gnuplot for display
#%end

import sys
import os
import atexit
import glob
from grass.script import core as grass

def cleanup():
    grass.try_remove('spectrum.gnuplot')
    for name in glob.glob('data_[0-9]*'):
	if name[5:].isdigit():
	   grass.try_remove(name)

    grass.try_remove('data_x')
    for name in glob.glob('data_y_[0-9]*'):
	if name[7:].isdigit():
	   grass.try_remove(name)

def draw_gnuplot(what, xlabels, output, label):
    xrange = 0

    for i, row in enumerate(what):
	outfile = 'data_%d' % i
	outf = file(outfile, 'w')
	xrange = max(xrange, len(row) - 2)
	for j, val in enumerate(row[3:]):
	    outf.write("%d %s\n" % (j + 1, val))
	outf.close()

    # build gnuplot script
    lines = []
    if output:
	lines += [
	    "set term png large",
	    "set output '%s'" % output
	    ]
    lines += [
	"set xtics (%s)" % xlabels,
	"set grid",
	"set title 'Spectral signatures'",
	"set xrange [0:%d]" % xrange,
	"set noclabel",
	"set xlabel 'Bands'",
	"set ylabel 'DN Value'",
	"set style data lines"
	]


    cmd = []
    for i, row in enumerate(what):
	if not label:
	    title = str(i + 1)
	else:
	    title = str(tuple(row[0:2]))
	cmd.append("'data_%d' title '%s'" % (i, title))
    cmd = ','.join(cmd)
    cmd = ' '.join(['plot', cmd, "with linespoints pt 779"])
    lines.append(cmd)

    plotfile = 'spectrum.gnuplot'
    plotf = file(plotfile, 'w')
    for line in lines:
	plotf.write(line + '\n')
    plotf.close()

    if output:
	grass.call(['gnuplot', plotfile])
    else:
	grass.call(['gnuplot', '-persist', plotfile])

def draw_linegraph(what):
    yfiles = []

    xfile = 'data_x'
    xf = file(xfile, 'w')
    for j, val in enumerate(what[0][3:]):
	xf.write("%d\n" % (j + 1))
    xf.close()

    for i, row in enumerate(what):
	yfile = 'data_y_%d' % i
	yf = file(yfile, 'w')
	for j, val in enumerate(row[3:]):
	    yf.write("%s\n" % val)
	yf.close()
	yfiles.append(yfile)

    sienna = '#%02x%02x%02x' % (160,  82,  45)
    coral  = '#%02x%02x%02x' % (255, 127,  80)
    gp_colors = ['red', 'green', 'blue', 'magenta', 'cyan', sienna, 'orange', coral]

    colors = gp_colors
    while len(what) > len(colors):
	colors += gp_colors
    colors = colors[0:len(what)]

    grass.run_command('d.linegraph', x_file = xfile, y_file = yfiles,
		      y_color = colors, title = 'Spectral signatures',
		      x_title = 'Bands', y_title = 'DN Value')


def main():
    group = options['group']
    raster = options['raster']
    output = options['output']
    coords = options['east_north']
    label = flags['c']
    gnuplot = flags['g']

    if not group and not raster:
	grass.fatal(_("Either group= or raster= is required"))

    if group and raster:
	grass.fatal(_("group= and raster= are mutually exclusive"))

    #check if present
    if gnuplot and not grass.find_program('gnuplot', ['-V']):
	grass.fatal(_("gnuplot required, please install first"))

    tmp1 = grass.tempfile()
    tmp2 = grass.tempfile()

    # get y-data for gnuplot-data file
    # get data from group files and set the x-axis labels

    if group:
	# ## PARSES THE GROUP FILES - gets rid of ugly header info from group list output
	s = grass.read_command('i.group', flags='g', group = group, quiet = True)
	rastermaps = s.splitlines()
    else:
	# ## get data from list of files and set the x-axis labels
	rastermaps = raster.split(',')

    xlabels = ["'%s' %d" % (n, i + 1) for i, n in enumerate(rastermaps)]
    xlabels = ','.join(xlabels)
    numbands = len(rastermaps)

    what = []
    s = grass.read_command('r.what', input = rastermaps, coordinates = coords, quiet = True)
    for l in s.splitlines():
	f = l.split('|')
	for i, v in enumerate(f):
	    if v in ['', '*']:
		f[i] = 0
	    else:
		f[i] = float(v)
	what.append(f)

    # build data files
    if gnuplot:
	draw_gnuplot(what, xlabels, output, label)
    else:
	draw_linegraph(what)

if __name__ == "__main__":
    options, flags = grass.parser()
    atexit.register(cleanup)
    main()