#!/usr/bin/env python
# -*- coding: utf-8 -*-

import pdb

import logging as mod_logging
import argparse as mod_argparse
import gpxpy as mod_gpxpy

import srtm as mod_srtm

parser = mod_argparse.ArgumentParser(
         description='Adds elevation to GPX files')

parser.add_argument('-o', '--overwrite', action='store_true', default=False,
                    help='Overwrite existing elevations (otherwise will add elevations only where not yet present)')
parser.add_argument('-p', '--approximate', action='store_true', default=False,
                    help='Approximate elevations with neighbour point elevations')
parser.add_argument('-s', '--smooth', action='store_true', default=False,
                    help='Smooth elevations')
parser.add_argument('-c', '--calculate', action='store_true', default=False,
                    help='Calculate elevations (but don\'t change the GPX file')
parser.add_argument('-f', '--file', default=None, type=str,
                    help='Output filename')
parser.add_argument('-v', '--verbose', action='store_true', default=False,
                    help='Verbose output')
parser.add_argument('gpx_files', nargs='*', help='GPX files')

args = parser.parse_args()

if args.verbose:
    mod_logging.basicConfig(level=mod_logging.DEBUG,
                            format='%(asctime)s %(name)-12s %(levelname)-8s %(message)s')

geo_elevation_data = mod_srtm.get_data()

def update_gpx(gpx):
    geo_elevation_data.add_elevations(gpx, only_missing=not args.overwrite, smooth=args.approximate)

for gpx_file in args.gpx_files:
    with open(gpx_file) as f:
        gpx = mod_gpxpy.parse(f.read())
        update_gpx(gpx)

        if args.smooth:
            print 'Smoothing...'
            gpx.smooth(vertical=True, horizontal=False)
            gpx.smooth(vertical=True, horizontal=False)
            print 'Smoothing... done'

        file_name = args.file
        if not file_name:
            if gpx_file.lower().endswith('.gpx' ):
                file_name = gpx_file[:-4] + '_with_elevations.gpx'
            else:
                file_name = 'gpx_with_elevations.gpx'

        with open(file_name, 'w') as output_f:
            output_f.write(gpx.to_xml())

            print
            print 'Written to %s' % file_name