#------------------------------------------------------------------------
# grd2xyz.py - This script converts an ESRI ascii grid into XYZ triplets
#              Values are centered in the cell.
#              Download Python free from www.python.org
#
#              Thanks to Leo Kreymborg for some pointers on speeding this
#              script up.
#
# David Finlayson
# February 3, 2004
# dfinlays@u.washington.edu
#------------------------------------------------------------------------

# Directions: Edit the filenames below, save the script in the directory
# with your ascii grid, and run (double-click) this script.

# --------------------- Make your changes here --------------------------

#infile = "S1870565.asc"               # ESRI ASCII Grid filename
#outfile = "output.xyz"             # output filename for x,y,z triplets

#  added by Alan Edmonds
#  Tk modules for selecting input file
#  10/25/2009
# import Tk modules

from Tkinter import *
import tkFileDialog
import tkMessageBox

# Open file for read

infile = tkFileDialog.askopenfilename(filetypes = [('Grid Filename', '*.asc'), ('Grid text file', '*.txt'), ('All Files', '*')],title='Select Input File')
outfile = infile[:-4] + '.xyz'
#

if tkMessageBox.askokcancel("Convert this file?",infile):
      
# end of Alan Edmonds additions
#
# --------------------- Below here, leave alone -------------------------
    def float2str(number):
        """ strips off trailing zeros from coordinates """
        s = "%f" % number
        if "." in s:
            s = s.rstrip("0").rstrip(".")
        return s

    # Load the grid files
    fin = open(infile, 'r')
    fout = open(outfile, 'w')

    # Read the header     
    line = fin.readline().split()
    ncol = int(line[1])

    line = fin.readline().split()
    nrow = int(line[1])

    line = fin.readline().split()
    xllcorner = float(line[1])

    line = fin.readline().split()
    yllcorner = float(line[1])

    line = fin.readline().split()
    cellsize = float(line[1])

    line = fin.readline().split()
    NODATA_value = float(line[1])

    # Pre-calculate the x and y coordinates

    xcoords = []
    for col in range(ncol):
        xcoords.append(float2str(xllcorner + (0.5 * cellsize) + (col * cellsize)))

    ycoords = []
    for row in range(nrow):
        ycoords.append(float2str(yllcorner - (0.5 * cellsize) + (nrow - row) * cellsize))

    # Process the file
    print "Converting %s to X,Y,Z triplets...\n" % (infile)
    for row in range(nrow):
        if (row % 100) == 0: print ".",
        for col in range(ncol):
            # Get new data if necessary
            if col == 0: line = fin.readline().split()
            #print xcoords[col], ycoords[col], line[col]                        
            fout.write("%s,%s,%s\n" % (xcoords[col], ycoords[row], line[col]))
            
    # Exit
    print "\nOutput file %s created" % (outfile)
    fin.close()
    fout.close()

    print "\nConversion complete.\n"
    # raw_input("Press ENTER to exit.\n")
    
# Alan Edmonds addition
# close input file
else:  
    exit