#!/usr/bin/python

"""
This script is designed to act as assistance in converting shapefiles
to OpenStreetMap data. This file is optimized and tested with MassGIS
shapefiles, converted to EPSG:4326 before being passed to the script.
You can perform this conversion with 

   ogr2ogr -t_srs EPSG:4326 new_file.shp old_file.shp

It is expected that you will modify the fixed_tags, tag_mapping, and
boring_tags attributes of this script before running. You should read,
or at least skim, the code up until it says:

  DO NOT CHANGE AFTER THIS LINE.

to accomodate your own data. 

Modified to support a maximum waylength and multiple outer ways in a
multipolygon relationship

adapted by devemux86
"""

__author__ = "Christopher Schmidt <crschmidt@crschmidt.net>"
__version__ = "$Id: polyshp2osm-WaterBody.py,v 1.3 2009/03/30 20:54:13 tbook Exp $"

gdal_install = """
Installing GDAL depends on your platform. Information is available at:
   
   http://trac.osgeo.org/gdal/wiki/DownloadingGdalBinaries

For Debian-based systems:

   apt-get install python-gdal

will usually suffice. 
"""

# These tags are attached to all exterior ways. You can put any key/value pairs
# in this dictionary. 

fixed_tags = {
  'natural': 'nosea',
  'layer': '-5'
}

# Here are a number of functions: These functions define tag mappings. The API
# For these functions is that they are passed the attributes from a feature,
# and they return a list of two-tuples which match to key/value pairs.

# The following Ftypes are not imported
# 46100 - Submerged Stream
ignoreField = "tile_x"
ignoreValues = []

# The following Ftypes are imported, but don't have any OSM tags attached:
# 36100 - Playa - An area from which water evaporates

def ftype(data):
    """Type of body - From NHD Ftype"""  
    natural = {
        'LakePond': 'water',
        'SwampMarsh': 'wetland'
    }

    if 'ftype' in data:
        if data['ftype'] in natural:
            return [('natural', natural[data['ftype']])]
    return None   

def fcode(data):
    """For features where the ftype is not specific enough"""
    landuse = {
        '43600': 'reservoir', #Reservoir
        '43601': 'reservoir', #Reservoir
        '43602': 'reservoir', #Reservoir
        '43603': 'reservoir', #Reservoir
        '43604': 'reservoir', #Reservoir
        '43605': 'reservoir', #Reservoir
        '43606': 'reservoir', #Reservoir
        '43607': 'reservoir', #Reservoir
        '43609': 'reservoir', #Reservoir
        '43610': 'reservoir', #Reservoir
        '43611': 'reservoir', #Reservoir
        '43612': 'reservoir', #Reservoir
        '43614': 'reservoir', #Reservoir
        '43615': 'reservoir', #Reservoir
        '43616': 'reservoir', #Reservoir
        '43617': 'reservoir', #Reservoir
        '43618': 'reservoir', #Reservoir
        '43619': 'reservoir', #Reservoir
        '43620': 'reservoir' #Reservoir
    }

    manmade = {
	'43613': 'reservoir_covered' #Covered Reservoir
    }

    leisure = {
        '43608': 'swimming_pool' #Swimming Pool
    }

    if 'fcode' in data:
        keys = []
        if data['fcode'] in landuse:
            keys.append( ('landuse', landuse[data['fcode']]) )
        if data['fcode'] in manmade:
            keys.append( ('man_made', manmade[data['fcode']]) )
        if data['fcode'] in leisure:
            keys.append( ('leisure', leisure[data['fcode']]) )
        return keys
    return None

# The most important part of the code: define a set of key/value pairs
# to iterate over to generate keys. This is a list of two-tuples: first
# is a 'key', which is only used if the second value is a string. In
# that case, it is a map of lowercased fieldnames to OSM tag names: so
# fee_owner maps to 'owner' in the OSM output.

# if the latter is callable (has a __call__; is a function), then that
# method is called, passing in a dict of feature attributes with
# lowercased key names. Those functions can then return a list of
# two-tuples to be used as tags, or nothin' to skip the tags.  


tag_mapping = [ 
    ('ftype', ftype),
    ('fcode', fcode),
    ('gnis_name', 'name'),
    ('gnis_id', 'gnis:feature_id'),
    ('elevation', 'ele'),
]    

# These tags are not exported, even with the source data; this should be
# used for tags which are usually calculated in a GIS. AREA and LEN are
# common.

boring_tags = [ 'error', 'tile_x', 'tile_y' ]

# Namespace is used to prefix existing data attributes. If 'None', or 
# '--no-source' is set, then source attributes are not exported, only
# attributes in tag_mapping.

namespace = "NHD"
#namespace = None 

# Uncomment the "DONT_RUN = False" line to get started. 

#DONT_RUN = True
DONT_RUN = False

# Set the maximum length of a way (in nodes) before it is split into
# shorter ways

Max_Waylength = 1500000

# =========== DO NOT CHANGE AFTER THIS LINE. ===========================
# Below here is regular code, part of the file. This is not designed to
# be modified by users.
# ======================================================================

import sys

try:
    try:
        from osgeo import ogr
    except ImportError:
        import ogr
except ImportError:
    __doc__ += gdal_install 
    if DONT_RUN:
        print __doc__
        sys.exit(2)
    print "OGR Python Bindings not installed.\n%s" % gdal_install
    sys.exit(1)

def close_file():
    """ Internal. Close an open file."""
    global open_file
    if not open_file.closed: 
        open_file.write("</osm>")
        open_file.close()

def start_new_file():
    """ Internal. Open a new file, closing existing file if neccesary."""
    global open_file, file_counter
    file_counter += 1
    if open_file:
        close_file()
    open_file = open("%s%s.osm" % (file_name, file_counter), "w")
    print >>open_file, "<osm version='0.6'>"

def clean_attr(val):
    """Internal. Hacky way to make attribute XML safe."""
    val = str(val)
    val = val.replace("&", "&amp;").replace("'", "&quot;").replace("<", "&lt;").replace(">", "&gt;").strip()
    return val

def add_ring_nodes(ring):
    """Internal. Write the outer ring nodes."""
    global open_file, id_counter
    ringways = []
    ids = []
    firstnode = id_counter
    if range(ring.GetPointCount() - 1) == 0 or ring.GetPointCount() == 0:
        print >>sys.stderr, "Degenerate ring." 
        return    
    for count in range(ring.GetPointCount() - 1):
        ids.append(id_counter)
        print >>open_file, "<node timestamp='1969-12-31T23:59:59Z' changeset='-1' id='%s' version='1' lon='%s' lat='%s' />" % (id_counter, ring.GetX(count), ring.GetY(count))
        id_counter += 1
        if (count > 0) and ((count % (Max_Waylength - 1)) == 0):
            ringways.append(ids)
            ids = []
	    ids.append(id_counter - 1)
    ids.append(firstnode)
    ringways.append(ids)
    return ringways    

def add_ring_way(ring): 
    """Internal. write out the 'holes' in a polygon."""
    global open_file, id_counter
    ids = []
    ringways = []
    for count in range(ring.GetPointCount() - 1):
        ids.append(id_counter)
        print >>open_file, "<node timestamp='1969-12-31T23:59:59Z' changeset='-1' version='1' id='%s' lon='%s' lat='%s' />" % (id_counter, ring.GetX(count), ring.GetY(count))
        id_counter += 1
    if len(ids) == 0:
        return None
    print >>open_file, "<way timestamp='1969-12-31T23:59:59Z' changeset='-1' id='%s' version='1'>" % id_counter
    way_id = id_counter
    id_counter += 1
    count = 0
    for i in ids:
        print >>open_file, "<nd ref='%s' />" % i
        count += 1
        if count >= Max_Waylength - 1:
            count = 0
            print >>open_file, "</way>"
            ringways.append(way_id)
            print >>open_file, "<way timestamp='1969-12-31T23:59:59Z' changeset='-1'id='%s' version='1'>" % id_counter
            way_id = id_counter
            id_counter += 1
            print >>open_file, "<nd ref='%s' />" % i
    print >>open_file, "<nd ref='%s' />" % ids[0]
    print >>open_file, "</way>"
    ringways.append(way_id)

    return ringways

open_file = None

file_name = None 

id_counter = 22951459320

file_counter = 0
counter = 0

class AppError(Exception): pass

def run(filename, slice_count=1, obj_count=100000000, output_location=None, no_source=False):
    """Run the converter. Requires open_file, file_name, id_counter,
    file_counter, counter to be defined in global space; not really a very good
    singleton."""
    global id_counter, file_counter, counter, file_name, open_file, namespace
    
    if no_source:
        namespace=None

    if output_location:
       file_name = output_location

    ds = ogr.Open(filename)
    if not ds:
        raise AppError("OGR Could not open the file %s" % filename)
    l = ds.GetLayer(0)
   
    max_objs_per_file = obj_count 

    extent = l.GetExtent()
    if extent[0] < -180 or extent[0] > 180 or extent[2] < -90 or extent[2] > 90:
        raise AppError("Extent does not look like degrees; are you sure it is? \n(%s, %s, %s, %s)" % (extent[0], extent[2], extent[1], extent[3]))  
    slice_width = (extent[1] - extent[0]) / slice_count

    seen = {}

    print "Running %s slices with %s base filename against shapefile %s" % (
            slice_count, file_name, filename)

    for i in range(slice_count): 

        l.ResetReading()
        l.SetSpatialFilterRect(extent[0] + slice_width * i, extent[2], extent[0] + (slice_width * (i + 1)), extent[3])

        start_new_file()
        f = l.GetNextFeature()
        
        obj_counter = 0
        last_obj_split = 0

        while f:
            start_id_counter = id_counter
            if f.GetFID() in seen:
                f = l.GetNextFeature()
                continue
            seen[f.GetFID()] = True             

#            done = False
#            while f.GetField(ignoreField) in ignoreValues:
#                if l.GetNextFeature() == None:
#                    done = True
#                    break
#                f = l.GetNextFeature()
#            if done == True:
#                break
            
            outerways = []
	    innerways = []
        
            geom = f.GetGeometryRef()
            ring = geom.GetGeometryRef(0)

            objcount = ring.GetPointCount()
            for i in range(1, geom.GetGeometryCount()):
	        objcount += geom.GetGeometryRef(i).GetPointCount()
	        objcount += 1

            if (obj_counter - last_obj_split + objcount) > max_objs_per_file:
                print "Splitting file with %s objs" % (obj_counter - last_obj_split)
                start_new_file()
                last_obj_split = obj_counter

            if objcount > max_objs_per_file:
                print "Warning: a feature contains %i objects which is more than the %i object limit.  It will be placed in a file by itself." % (objcount, max_objs_per_file)

            ringways = add_ring_nodes(ring)
            if not ringways or len(ringways) == 0:
                f = l.GetNextFeature()
                continue
# Write out the outer ways in the relation
            for count in range( len(ringways) ):
                ids = ringways[count]
                if ids and len(ids) > 1: 
                    print >>open_file, "<way timestamp='1969-12-31T23:59:59Z' changeset='-1' id='%s' version='1'>" % id_counter
                    outerways.append(id_counter) 
                    id_counter += 1
                    for i in ids:
                        print >>open_file, "<nd ref='%s' />" % i
#Write out the fields for the way
                    field_count = f.GetFieldCount()
                    fields  = {}
                    for field in range(field_count):
                        value = f.GetFieldAsString(field)
                        name = f.GetFieldDefnRef(field).GetName()
                        if namespace and name and value and name not in boring_tags:
                            print >>open_file, "<tag k='%s:%s' v='%s' />" % (namespace, name, clean_attr(value))
                        fields[name.lower()] = value
                    tags={}
#Perform the specified field mappting
                    for tag_name, map_value in tag_mapping:
                        if hasattr(map_value, '__call__'):
                            tag_values = map_value(fields)
                            if tag_values:
                                for tag in tag_values:
                                    tags[tag[0]] = tag[1]
                        else:
                            if tag_name in fields:
                                tags[map_value] = fields[tag_name].title()
                    for key, value in tags.items():
                        if key and value:
                            print >>open_file, "<tag k='%s' v='%s' />" % (key, clean_attr(value))
#Write fixed tabs                    
                    for name, value in fixed_tags.items():
                        print >>open_file, "<tag k='%s' v='%s' />" % (name, clean_attr(value))
                    print >>open_file, "</way>"
            if (geom.GetGeometryCount() > 1) or (len(ringways) > 1):
#add the inner ways
                for i in range(1, geom.GetGeometryCount()):
                    ringways = add_ring_way(geom.GetGeometryRef(i)) 
                    for way in ringways:
                        innerways.append(way)
                print >>open_file, "<relation timestamp='1969-12-31T23:59:59Z' changeset='-1' id='%s' version='1' ><tag k='type' v='multipolygon' />" % id_counter
                id_counter += 1
                for way in outerways:
                    print >>open_file, '<member type="way" ref="%s" role="outer" />' % way
                for way in innerways:
                    print >>open_file, '<member type="way" ref="%s" role="inner" />' % way 
                print >>open_file, "</relation>"    
                
            counter += 1
            f = l.GetNextFeature()
            obj_counter += (id_counter - start_id_counter)
        
        close_file()

if __name__ == "__main__":
    if DONT_RUN:
        print __doc__
        sys.exit(2)
    
    from optparse import OptionParser
    
    parse = OptionParser(usage="%prog [args] filename.shp", version=__version__)
    parse.add_option("-s", "--slice-count", dest="slice_count", 
                     help="Number of horizontal slices of data", default=1, 
                     action="store", type="int")
    parse.add_option("-o", "--obj-count", 
                     dest="obj_count", 
                     help="Maximum number of objects in a single .osm file", 
                     default=1000000, type="int")
    parse.add_option("-n", "--no-source", dest="no_source", 
                     help="Do not store source attributes as tags.",
                     action="store_true", default=False)
    parse.add_option("-l", "--output-location", 
                        dest="output_location", help="base filepath for output files.", 
                        default="poly_output") 
    (options, args) = parse.parse_args()
    
    if not len(args):
        print "No shapefile name given!"
        parse.print_help()
        sys.exit(3)

    kw = {}
    for key in  ('slice_count', 'obj_count', 'output_location', 'no_source'):
        kw[key] = getattr(options, key)
    
    try:
        run(args[0], **kw)   
    except AppError, E:
        print "An error occurred: \n%s" % E