#!/usr/bin/env python

#   Copyright ©Dave Pawson 2007
#    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 3 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, see <http://www.gnu.org/licenses/>.


import sys
import codecs
import string
import os
from   optparse import OptionParser
from   decimal import Decimal
import fpformat

#
# Module function: 
#
function ="""This program does the following things
0. Assumes you have processed an image containing exif metadata, using
 $exiftool -a -u -g1 -s -t <infile>
1. reads input params for filename(s)
2. Parses the file(s)
3. Converts to N3 rdf
5. Re-writes the files in N3, with extension @@FIXME


"""
version="1.2"
date ="2007-08-17"
outfile=""
out=None
infile=""
prog ="exifrdf"
copyright="Copyrght (C) 2007 Dave Pawson"
requiredArgs=2
description=False # don't add dc:title, dc:description
geo=False # don't add geo data
setOpt = False # command line boolean
debug=0

#
#Metadata globals
#
filename=''   # filename
path=''       # path to filename
width=0       # Image width, px?
height=0      # Image height, px?



def mainProg():
    global infile,outfile
    global out
    header()
    if (debug >5):
        print "Processing %s to %s" % (infile, outfile) 
    inp = codecs.open(infile,"r","utf-8")
    for line in inp:
        processLine(line)
    if (debug == 4):
        print "Meta: path %s\n file %s\n width %s\n Height %s" % (path, filename, width, height)
    inp.close()
    tail()
    out.close()
    return


#
#Process a single line of the exif data
#
def processLine(line):
    if line[0:4] =="----":
        if debug > 3:
         print "*****************Section %s" % line[4:-4]
        out.write("# %s\n" % line[4:-4])
    else:
        tag= line.split('\t')[0]
        value=line.split('\t')[1]
        value=value[0:-1]
        out.write("exif:%s \"%s\";\n" %(tag,value))
        extractMeta(tag, value)
    return



#
#Extract @@FIXME values from exif data
#
def extractMeta(tag, value):
    global filename, path, width, height
    if (tag=='FileName'):
        filename=value
    if (tag =='Directory'):
        if (value=='.'):
            path=os.getcwd() # replace . by actual directory
        else:
            path=value
        path = path + os.sep
    if (tag =='ImageWidth'):
        width=value
    if (tag == 'ImageHeight'):
        height=value
        
        

#
# Select a geo position from a list
# returns the geo string e.g. geo:lat 52.2345; \n geo:long -93.1234
# E.g. see http://www.realestate3d.com/gps/world-latlong.htm    
def selectGeo():
    geos =  {
        'home' : "00.00 -1.00",
        'hitchin' : "51.54 -0.14",
        'karachi' : "24.85 67.033"
        }
    l = []
    #input = raw_input("Select geo tags? Hit any key to select or Return to skip > ")
    key = 0
    for nm,loc in geos.iteritems():
        print "%i %s" %(key, nm)
        l.append(nm)
        key +=1
    while 1:
        input = raw_input("Enter a number, Rtn to skip >")
        if input:
            idx = string.atoi(input,0)
            if idx < len(l):
                input = l[idx ]
                if geos.has_key(input):
                    (lat,lon) = string.split(geos[input]," ")
                    #print "Using Name, %s Lat %s, Long %s " % (input, lat, lon)
                    return "geo:lat %s;\ngeo:long %s;" % (lat, lon)
                    break
                else:
                    print "Entry not found, try again"
        break


#
#See if user wants to enter actual coordinates, or select 
# from an existing position.
#
def trygeo():
    while 1:
        print("Enter position of photo?  ")
        resp = raw_input("e to enter values, s to select from list, Rtn to skip ")
        if resp:
            if resp=="e":
                return getPos()
            if resp=="s":
                return selectGeo()
            else:
                print "Invalid selection"
        else:
            return ""
            

#
#Obtain Lat and Long from user
#
def getPos():
    while 1:
        lat =raw_input("Enter latitude, -90 ... +90 ")
        if lat:
            latn = float(lat)
            if (-90.0 < latn) and (latn < 90.):
                break
            else:
                print "Invalid"
    while 1:
        lon =raw_input("Enter longitudeitude, -90 ... +90 ")
        if lon:
            lonn = float(lon)
            if (-180.0 < lonn) and (lonn < 180.):
                break
            else:
                print "Invalid"
    return "geo:lat %s;\ngeo:long %s;" % (latn, lonn)


#
#Print out the header
#
def header():
    headertxt="""
# -*- N3 -*-
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix log: <http://www.w3.org/2000/10/log#>.
@prefix xs: <http://www.w3.org/2001/XMLSchema#> .
@prefix exif: <http://exif.org/ns#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix dc: <http://purl.org/dc/elements/1.1#> .
@prefix dcterms: <http://dublincore.org/documents/2005/06/13/dcmi-terms/>.
@prefix foaf: <http://xmlns.com/foaf/0.1/20050603.rdf>.
@prefix wordnet: <http://xmlns.com/wordnet/1.6/ontology/>.
@prefix geo: <http://www.w3.org/2003/01/geo/wgs84_pos#>.
@prefix lang: <http://downlode.org/rdf/iso-639/#>.
@prefix : <#> .
"""
    out.write(headertxt)
    out.write ("exif:data a exif:dataset;\n")
    out.write ("dc:date \"%s\";\n" % date)
    

#
#Output the tail of the piece
#
def tail():
    if description:
        input = raw_input("Enter dc:title >")
        if input:
            out.write( "dc:title \"%s\";\n" % input)
            input = raw_input("Enter dc:description >")
        if input:
            out.write("dc:description \"%s\";\n" % input)
    if geo:
        out.write(trygeo())
    out.write(".\n\n")


#
# Print usage instructions
#
def usage():
    str="""
%s.py, Version %s Date %s %s
Assumes you have processed an image containing exif metadata, using

 $exiftool -a -u -g1 -s -t <infile>

This program processes the output of that tool. 

$> python %s.py -i infile -o outfile  [options]
for console output set -o -

""" % (prog, version, date, copyright, prog)
    return str


#
# Main program entry
#

def main():
    global infile, outfile, description, out, geo
    parser = OptionParser(usage=usage())
    parser.add_option("-i","--input",dest="infilenm",
                      help="Input file to process")
    parser.add_option("-o","--output",dest="outfilenm",
                      default="-",
                      help="Output filename for results")
    parser.add_option("-d", action="store_true", dest="description",
                      help="set to add title and description"
                      )
    parser.add_option("-g", action="store_true", dest="geo",
                      help="set to add geographical data, lat and long")
    (options, args) = parser.parse_args()
    if not (options.infilenm ):
        parser.print_help()
        sys.exit(2)
    infile =options.infilenm
    if options.outfilenm=="" :
        outfile=sys.stdout
    else:
        outfile=options.outfilenm
    description = options.description
    geo = options.geo
    #Now validate parameters
    #if not( os.path.isdir(directory)):
    #    sys.stderr.write ("\t\t Error, '%s' is not a directory\n" % directory) 
    #    sys.exit(2)
    if not(os.path.isfile(infile)):
        sys.stderr.write ("\t\t Error, %s should be a file\n" % infile) 
        sys.exit(2)
    try:
        if (outfile <>"-"):
            out = open(outfile,'w')
        else:
            out = sys.stdout
    except EnvironmentError:
        sys.stderr.write("%s not writable, Quitting" %outfile)
        sys.exit(2)    
    if debug > 5:
        print "%s.main: %s Version %s, Processing %s to %s" % (prog,prog,version,infile,outfile)
    mainProg()
    if (debug > 5): sys.stderr.write("%s.main, Finished" % (prog))
 


if __name__ == '__main__':
    main()