from osgeo.osr import SpatialReference, CoordinateTransformation
import shapefile

epsg28992 = SpatialReference()
epsg28992.ImportFromEPSG(28992)

epsg28992.SetTOWGS84(565.237 ,50.0087 ,465.658 ,-0.406857 ,0.350733 ,-1.87035 ,4.0812)

epsg4326 = SpatialReference()
epsg4326.ImportFromEPSG(4326)

rd2latlon = CoordinateTransformation(epsg28992, epsg4326)


def rd_to_longlat(rd_multipolygon):
    if len(rd_multipolygon) == 2 and tuple(map(type, rd_multipolygon)) == (float, float):
        return list(rd2latlon.TransformPoint(*rd_multipolygon)[:2])
    return [
        rd_to_longlat(element)
        for element in rd_multipolygon
    ]


def shapefiles_to_geojson(filename):
    shape_file = shapefile.Reader(filename)
    fields = shape_file.fields[1:]
    field_names = [field[0] for field in fields]

    buffer = []
    for shape_record in shape_file.shapeRecords():
        properties = dict(zip(field_names, shape_record.record))
        geometry = shape_record.shape.__geo_interface__
        geometry['coordinates'] = rd_to_longlat(geometry['coordinates'])

        buffer.append({
            'type': "Feature",
            'geometry': geometry,
            'properties': properties
        })
    return {
        "type": "FeatureCollection",
        "features": buffer
    }