"""

 This module houses the GEOS ctypes prototype functions for the 

 unary and binary predicate operations on geometries.

"""

from ctypes import c_char, c_char_p, c_double

from django.contrib.gis.geos.libgeos import lgeos, GEOM_PTR

from django.contrib.gis.geos.prototypes.errcheck import check_predicate

## Binary & unary predicate functions ##

def binary_predicate(func, *args):

    "For GEOS binary predicate functions."

    argtypes = [GEOM_PTR, GEOM_PTR]

    if args: argtypes += args

    func.argtypes = argtypes

    func.restype = c_char

    func.errcheck = check_predicate

    return func

def unary_predicate(func):

    "For GEOS unary predicate functions."

    func.argtypes = [GEOM_PTR]

    func.restype = c_char

    func.errcheck = check_predicate

    return func

## Unary Predicates ##

geos_hasz = unary_predicate(lgeos.GEOSHasZ)

geos_isempty = unary_predicate(lgeos.GEOSisEmpty)

geos_isring = unary_predicate(lgeos.GEOSisRing)

geos_issimple = unary_predicate(lgeos.GEOSisSimple)

geos_isvalid = unary_predicate(lgeos.GEOSisValid)

## Binary Predicates ##

geos_contains = binary_predicate(lgeos.GEOSContains)

geos_crosses = binary_predicate(lgeos.GEOSCrosses)

geos_disjoint = binary_predicate(lgeos.GEOSDisjoint)

geos_equals = binary_predicate(lgeos.GEOSEquals)

geos_equalsexact = binary_predicate(lgeos.GEOSEqualsExact, c_double)

geos_intersects = binary_predicate(lgeos.GEOSIntersects)

geos_overlaps = binary_predicate(lgeos.GEOSOverlaps)

geos_relatepattern = binary_predicate(lgeos.GEOSRelatePattern, c_char_p)

geos_touches = binary_predicate(lgeos.GEOSTouches)

geos_within = binary_predicate(lgeos.GEOSWithin)