import grass.script as grass 
try:
    from owslib.wfs import WebFeatureService
    from owslib.util import ServiceException
except:
    grass.fatal(_("OSWLib can not be found. Install OSWLib (http://geopython.github.com/OWSLib/) or use GRASS driver."))

from wfs_base import WFSBase

class WFSOwsLibDrv(WFSBase):
    def _download(self):
        """!Downloads data from WFS server using OSWlLib driver
        
        @return temp_map with downloaded data
        """ 
        grass.message(_("Downloading data from WFS server..."))

        if self.bbox:
            query_bbox = (self.bbox['minx'],  self.bbox['miny'],  self.bbox['maxx'],  self.bbox['maxy'])
        else:
            query_bbox = self.bbox

        wfs = WebFeatureService(url = self.o_url, version= self.o_wfs_version)
  
        try:
            wfs_data = wfs.getfeature( typename = [self.o_layers],
                                       srsname =  "EPSG:" + str(self.o_srs),
                                       maxfeatures = self.o_maximum_features,
                                       bbox = query_bbox)   
        #TODO do it better                                         
        except ServiceException as e:
            grass.fatal(_("Server returned exception"))

        grass.debug(url)

        temp_map = self._temp()
                
        # download data into temporary file
        try:
            temp_map_opened = open(temp_map, 'w')
            temp_map_opened.write(wfs_data.read())
            temp_map_opened
        except IOError:
            grass.fatal(_("Unable to write data into tempfile"))
        finally:
            temp_map_opened.close()

        return temp_map