#!/usr/bin/env python

"""
Export line (road) geometries from the database to Keyhole Markup
Language (KML). The exported roads should have both a human-readable
name and a globally-unique identifier (gid).
"""

import os
import pgdb
import site
import sys

# Basically, add '../src' to our path.
# Needed for the imports that follow.
site.addsitedir(os.path.dirname(os.path.abspath(sys.argv[0])) + '/../src')

import CLI
import Configuration.Defaults
import ExitCodes
import KML


"""
Parse the command line options. All of these are optional; defaults
are provided for the database information and the output is written
to stdout.
"""

parser = CLI.default_option_parser()

# Use this module's docstring as the description.
parser.description = __doc__.strip()

parser.add_option('-s',
                  '--state',
                  help='The FIPS id of the State whose roads you would like.')

(options, args) = parser.parse_args()


conn = pgdb.connect(host=options.host,
                    database=options.database,
                    user=options.username)


# We'll use this cursor for all of our queries.
cursor = conn.cursor()

# If no state is passed on the command line, we want to select the
# roads for all states.  "... WHERE statefp=statefp ..." will
# accomplish this.
statefp = 'statefp'
if (options.state != None):
    # The statefp column is a string, so we need to add single quotes
    # if we're going to specify it.
    statefp = "'%s'" % options.state

lines_query = """
SELECT gid, tlid, fullname, ST_AsKml(the_geom)
FROM tiger_lines
WHERE statefp=%s
""" % statefp

cursor.execute(lines_query)
rows = cursor.fetchall()
doc = KML.Document()

for row in rows:
    placemark = KML.Placemark()

    # Name = "Street name (tlid)"
    fullname = row[2]
    
    if (fullname == None):
        # Some streets don't have a fullname.
        fullname = 'Unknown'
        
    name = KML.Name(fullname + ' (' + str(row[1]) + ')')
    
    placemark.children.append(name)
    geometry = KML.RawText(row[3])
    placemark.children.append(geometry)    
    doc.children.append(placemark)
    
doc.print_kml()

conn.close()