mapnik/bindings/python/mapnik_feature.cpp

/*****************************************************************************
 * 
 * This file is part of Mapnik (c++ mapping toolkit)
 *
 * Copyright (C) 2006 Artem Pavlenko, Jean-Francois Doyon
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 *****************************************************************************/
//$Id$

// boost
#include <boost/python/suite/indexing/indexing_suite.hpp>
#include <boost/python/iterator.hpp>
#include <boost/python/call_method.hpp>
#include <boost/python/tuple.hpp>
#include <boost/python.hpp>
#include <boost/scoped_array.hpp>
// mapnik
#include <mapnik/feature.hpp>
#include <mapnik/datasource.hpp>

mapnik::geometry2d & (mapnik::Feature::*get_geom1)(unsigned) = &mapnik::Feature::get_geometry;

namespace boost { namespace python {
struct value_converter : public boost::static_visitor<PyObject*>
{
    PyObject * operator() (int val) const
    {
	return ::PyInt_FromLong(val);
    }
            
    PyObject * operator() (double val) const
    {
	return ::PyFloat_FromDouble(val);
    }
            
    PyObject * operator() (UnicodeString const& s) const
    {
	std::string buffer;
	mapnik::to_utf8(s,buffer);
	PyObject *obj = Py_None;
	obj = ::PyUnicode_DecodeUTF8(buffer.c_str(),implicit_cast<ssize_t>(buffer.length()),0);                
	return obj;
    }
            
    PyObject * operator() (mapnik::value_null const& s) const
    {
	return NULL;
    }
};
      
struct mapnik_value_to_python
{
    static PyObject* convert(mapnik::value const& v)
    {
	return boost::apply_visitor(value_converter(),v.base());
    }
};
      
// Forward declaration
template <class Container, bool NoProxy, class DerivedPolicies>
class map_indexing_suite2;

namespace detail
{
template <class Container, bool NoProxy>
class final_map_derived_policies
    : public map_indexing_suite2<Container,
				 NoProxy, final_map_derived_policies<Container, NoProxy> > {};
}
    
template <
class Container,
bool NoProxy = false,
class DerivedPolicies
= detail::final_map_derived_policies<Container, NoProxy> >
class map_indexing_suite2
    : public indexing_suite<
Container
, DerivedPolicies
, NoProxy
, true
, typename Container::value_type::second_type
, typename Container::key_type
, typename Container::key_type
>
{
public:

    typedef typename Container::value_type value_type;
    typedef typename Container::value_type::second_type data_type;
    typedef typename Container::key_type key_type;
    typedef typename Container::key_type index_type;
    typedef typename Container::size_type size_type;
    typedef typename Container::difference_type difference_type;

    template <class Class>
    static void
    extension_def(Class& cl)
    {
               
    }

    static data_type&
    get_item(Container& container, index_type i_)
    {
	typename Container::iterator i = container.props().find(i_);
	if (i == container.end())
	{
	    PyErr_SetString(PyExc_KeyError, "Invalid key");
	    throw_error_already_set();
	}
	return i->second;
    }
            
    static void
    set_item(Container& container, index_type i, data_type const& v)
    {
	container[i] = v;
    }
            
    static void
    delete_item(Container& container, index_type i)
    {
	container.props().erase(i);
    }
	  
    static size_t
    size(Container& container)
    {
	return container.props().size();
    }
	  
    static bool
    contains(Container& container, key_type const& key)
    {
	return container.props().find(key) != container.end();
    }
            
    static bool
    compare_index(Container& container, index_type a, index_type b)
    {
	return container.props().key_comp()(a, b);
    }
            
    static index_type
    convert_index(Container& /*container*/, PyObject* i_)
    {
	extract<key_type const&> i(i_);
	if (i.check())
	{
	    return i();
	}
	else
	{
	    extract<key_type> i(i_);
	    if (i.check())
		return i();
	}
               
	PyErr_SetString(PyExc_TypeError, "Invalid index type");
	throw_error_already_set();
	return index_type();
    }
};
      

template <typename T1, typename T2>
struct std_pair_to_tuple
{
    static PyObject* convert(std::pair<T1, T2> const& p)
    {
	return boost::python::incref(
	    boost::python::make_tuple(p.first, p.second).ptr());
    }
};
      
template <typename T1, typename T2>
struct std_pair_to_python_converter
{
    std_pair_to_python_converter()
    {
	boost::python::to_python_converter<
	std::pair<T1, T2>,
	    std_pair_to_tuple<T1, T2> >();
    }
};
}
}

mapnik::feature_ptr create_feature_(int id)
{
    return mapnik::feature_ptr(new mapnik::Feature(id));
}

struct UnicodeString_from_python_str
{
    UnicodeString_from_python_str()
    {
	boost::python::converter::registry::push_back(
	    &convertible,
	    &construct,
	    boost::python::type_id<UnicodeString>());
    }

    static void* convertible(PyObject* obj_ptr)
    {
	if (!PyString_Check(obj_ptr)) return 0;
	return obj_ptr;
    }

    static void construct(
	PyObject* obj_ptr,
	boost::python::converter::rvalue_from_python_stage1_data* data)
    {
	const char* value = PyString_AsString(obj_ptr);
	if (value == 0) boost::python::throw_error_already_set();
	void* storage = (
	    (boost::python::converter::rvalue_from_python_storage<UnicodeString>*)
	    data)->storage.bytes;
	new (storage) UnicodeString(value);
	data->convertible = storage;
    }
};

void export_feature()
{
    using namespace boost::python;
    using mapnik::Feature;
      
    implicitly_convertible<int,mapnik::value>();
    implicitly_convertible<double,mapnik::value>();
    implicitly_convertible<UnicodeString,mapnik::value>();
    implicitly_convertible<bool,mapnik::value>();

    std_pair_to_python_converter<std::string const,mapnik::value>();
    to_python_converter<mapnik::value,mapnik_value_to_python>();
    UnicodeString_from_python_str();
   
    class_<Feature,boost::shared_ptr<Feature>,
	boost::noncopyable>("Feature",no_init)
	.def("id",&Feature::id)
	.def("__str__",&Feature::to_string)
//	.add_property("properties", 
//		      make_function(&Feature::props,return_value_policy<reference_existing_object>()))
    //      .def("add_geometry", // TODO define more mapnik::Feature methods
	.def("num_geometries",&Feature::num_geometries)
	.def("get_geometry", make_function(get_geom1,return_value_policy<reference_existing_object>()))
	.def("envelope", &Feature::envelope)
	.def("create",create_feature_)
	.staticmethod("create")
	.def(map_indexing_suite2<Feature, true >())
	.def("iteritems",iterator<Feature> ())
	;
   
//def("Feature", &create_feature_);
   
//class_<std::map<std::string, mapnik::value> >("Properties")
//   .def(map_indexing_suite2<std::map<std::string, mapnik::value>, true >())
//  .def("iteritems",iterator<std::map<std::string,mapnik::value> > ())
//     ;
}