#!/usr/local/bin/python2.7
###############################################################################
# $Id: get_soundg.py 54587021942e38164ce1cd8009e74933fd328f38 2018-04-18 03:01:56 +1000 Ben Elliston $
#
# Project:  OGR Python samples
# Purpose:  Extract SOUNDGings from an S-57 dataset, and write them to
#           Shapefile format, creating one feature for each sounding, and
#           adding the elevation as an attribute for easier use.
# Author:   Frank Warmerdam, warmerdam@pobox.com
#
###############################################################################
# Copyright (c) 2003, Frank Warmerdam <warmerdam@pobox.com>
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
# DEALINGS IN THE SOFTWARE.
###############################################################################

import sys

from osgeo import ogr

#############################################################################


def Usage():
    print('Usage: get_soundg.py <s57file> <shapefile>')
    print('')
    sys.exit(1)

#############################################################################
# Argument processing.


if len(sys.argv) != 3:
    Usage()

s57filename = sys.argv[1]
shpfilename = sys.argv[2]

# -
# Open the S57 file, and find the SOUNDG layer.

ds = ogr.Open(s57filename)
src_soundg = ds.GetLayerByName('SOUNDG')

# -
# Create the output shapefile.

shp_driver = ogr.GetDriverByName('ESRI Shapefile')
shp_driver.DeleteDataSource(shpfilename)

shp_ds = shp_driver.CreateDataSource(shpfilename)

shp_layer = shp_ds.CreateLayer('out', geom_type=ogr.wkbPoint25D)

src_defn = src_soundg.GetLayerDefn()
field_count = src_defn.GetFieldCount()

# -
# Copy the SOUNDG schema, and add an ELEV field.

out_mapping = []
for fld_index in range(field_count):
    src_fd = src_defn.GetFieldDefn(fld_index)

    fd = ogr.FieldDefn(src_fd.GetName(), src_fd.GetType())
    fd.SetWidth(src_fd.GetWidth())
    fd.SetPrecision(src_fd.GetPrecision())
    if shp_layer.CreateField(fd) != 0:
        out_mapping.append(-1)
    else:
        out_mapping.append(shp_layer.GetLayerDefn().GetFieldCount() - 1)

fd = ogr.FieldDefn('ELEV', ogr.OFTReal)
fd.SetWidth(12)
fd.SetPrecision(4)
shp_layer.CreateField(fd)

#############################################################################
# Process all SOUNDG features.

feat = src_soundg.GetNextFeature()
while feat is not None:

    multi_geom = feat.GetGeometryRef()

    for iPnt in range(multi_geom.GetGeometryCount()):
        pnt = multi_geom.GetGeometryRef(iPnt)

        feat2 = ogr.Feature(feature_def=shp_layer.GetLayerDefn())

        for fld_index in range(field_count):
            feat2.SetField(out_mapping[fld_index], feat.GetField(fld_index))

        feat2.SetField('ELEV', pnt.GetZ(0))
        feat2.SetGeometry(pnt)
        shp_layer.CreateFeature(feat2)
        feat2.Destroy()

    feat.Destroy()

    feat = src_soundg.GetNextFeature()

#############################################################################
# Cleanup

shp_ds.Destroy()
ds.Destroy()
