#!/usr/local/bin/python
#================================================================
# routebox:  What is the bounding box of a specific route?
#       $Revision: 1.5 $  $Date: 2009/10/04 20:25:22 $
#----------------------------------------------------------------
# Usage:
#   routebox wayfile [route-id]
# where:
#   wayfile     Names a waypoint file in XML conforming to
#               waypoints.dtd
#   route-id    Is the `id=' attribute of a route in that file;
#               default is all routes
# Output:  A range of latitudes and longitudes that covers all
# the waypoints in that route.
#----------------------------------------------------------------


#================================================================
# Imports
#----------------------------------------------------------------

import sys                  # Standard Python system interface
import waypointset          # Represents the waypoints file


# - - -   l a t L o n F o r m a t   - - -

def latLonFormat ( latLon ):
    """Formats a lat-long in the way expected by `buildmapbase'.

      [ latLon is a terrapos.TerraPosition object ->
          return latLon as a string with `n/s' and `e/w' directions ]
    """
    #-- 1 --
    # [ ns  :=  latitude as "n" for north, "s" for south
    #   ew  :=  longitude as "e" for east, "w" for west ]
    if  latLon.latDeg < 0:  ns  =  "s"
    else:                   ns  =  "n"

    if  latLon.lonDeg < 0:  ew  =  "w"
    else:                   ew  =  "e"

    #-- 2 --
    # [ return (abs(latLon.latDeg) + ns + abs(latLon.lonDeg) + ew ]
    return "%.5f%s%.5f%s" % ( abs(latLon.latDeg), ns,
                              abs(latLon.lonDeg), ew )


# - - - - -   m a i n   - - - - -

#-- 1 --
# [ if the command line arguments are valid ->
#     wayFileName  :=  name of the waypoints file
#     routeId      :=  the route-id, or None if omitted
#   else ->
#     sys.stderr  +:=  error message
#     stop execution ]
argList  =  sys.argv[1:]
if  not ( 1 <= len(argList) <= 2 ):
    sys.stderr.write ( "*** Arguments: wayfile route-id\n" )
    sys.exit(1)
else:
    wayFileName  =  argList[0]
    if  len(argList) > 1:
        routeId  =  argList[1]
    else:
        routeId  =  None

#-- 2 --
# [ if wayFileName names a readable, valid waypoints file ->
#     waypointSet  :=  a WaypointSet object representing that file
#   else ->
#     sys.stderr  +:=  error message
#     stop execution ]
try:
    waypointSet  =  waypointset.WaypointSet ( wayFileName )
except IOError, detail:
    sys.stderr.write ( "*** Can't read the waypoint file '%s': %s\n" %
                       (wayFileName, detail) )
    sys.exit(1)

#-- 3 --
# [ if routeId is None ->
#     geoBox  :=  bounding box of waypointSet
#   else if routeId matches a route id in waypointSet ->
#     geoBox  :=  bounding box of that route in waypointSet
#   else ->
#     sys.stderr  +:=  error message
#     stop execution ]
if  routeId is None:
    geoBox  =  waypointSet.geoBox
else:
    try:
        route  =  waypointSet.getRoute ( routeId )
        geoBox  =  route.geoBox
    except KeyError:
        sys.stderr.write ( "*** No such route: %s\n" % routeId )
        sys.exit(1)

#-- 4 --
# [ sys.stdout  +:=  geoBox ]
print latLonFormat ( geoBox.sw )
print latLonFormat ( geoBox.ne )