#!/usr/bin/env python
# coding=utf-8

from OWS import OWS
import mapscript
from osgeo import gdal
from osgeo import ogr
from osgeo import osr
import os
import logging
import re

class WMS(OWS):

    service = "WMS"
    request = '' # GetCapabilies, ...
    parser = None
    version = None

    def __init__(self,url=None,qstring=None,configFile=None):
        OWS.__init__(self,url,qstring,configFile)

    def makeMap(self,mapfilename=None):
        """Create mapscript.mapObj"""

        mapobj = self.getMapObj(mapfilename)


        params = self.getParams()


        self.version = params["VERSION"][0]

        # create layer
        logging.debug("Creating layer %s" % params["LAYERS"][0]) 
        lyrobj = mapscript.layerObj(mapobj)
        lyrobj.name = params["LAYERS"][0]
        lyrobj.type = mapscript.MS_LAYER_RASTER
        lyrobj.connection = params["OWSURL"][0]
        lyrobj.status = mapscript.MS_DEFAULT
        lyrobj.setConnectionType(mapscript.MS_WMS,None)
        lyrobj.setMetaData("wms_srs",params["FROMCRS"][0])
        lyrobj.setMetaData("wms_name",params["LAYERS"][0])
        lyrobj.setMetaData("wms_server_version",params["VERSION"][0])
        lyrobj.setMetaData("wms_exceptions_format",params["EXCEPTIONS"][0])
        lyrobj.setMetaData("wms_formatlist",params["FORMAT"][0])
        lyrobj.setMetaData("wms_style",params["STYLES"][0])
        lyrobj.setMetaData("wms_transparent",params["TRANSPARENT"][0])
        lyrobj.setMetaData("gml_include_items","all")
        lyrobj.template = "foo"

        self.saveMapfile(mapobj,mapfilename)
        return mapobj

    def getTime(self,ds,lyrobj):
        """Generate time index file, set approripate layer metadata"""

        # make time index file
        drv = ogr.GetDriverByName("ESRI Shapefile")
        tindex = '%s.%s.%s'%(lyrobj.name,self.service.lower(),"tindex")
        logging.info("Creating time index definition file %s.shp in %s" % (tindex,self.cachedir))
        tds = drv.CreateDataSource(os.path.join(self.cachedir,tindex))
        lyr = tds.CreateLayer(tindex)
        tile_field = ogr.FieldDefn("location", ogr.OFTString )
        tile_field.SetWidth( 256 )
        lyr.CreateField(tile_field)

        time_field = ogr.FieldDefn("time", ogr.OFTString )
        time_field.SetWidth( 256 )
        lyr.CreateField(time_field)

        timeMetadata = ""
        for sds in ds.GetSubDatasets():
            if sds[0].find('time') > -1:
                # crate mapfile metadata
                sdsname = sds[0].split(",")[0]
                sdsvalue = re.findall(r'".*"',sdsname)[0].replace('"',"")
                timeMetadata = timeMetadata+","+sdsvalue

                # create OGR tindex vector feature
                feature = ogr.Feature(lyr.GetLayerDefn())

                # feature geometry
                geotransform = ds.GetGeoTransform()
                w = ds.RasterXSize
                h = ds.RasterYSize
                bbox = {"minx":geotransform[0],"miny":geotransform[5]*h+geotransform[3],"maxx":geotransform[1]*w+geotransform[0],"maxy":geotransform[3]}
                poly = ogr.CreateGeometryFromWkt("""POLYGON((%(minx)s %(miny)s, %(maxx)s %(miny)s, %(maxx)s %(maxy)s, %(minx)s %(maxy)s, %(minx)s %(miny)s))""" % bbox)
                feature.SetGeometry(poly)

                # set time attribute
                feature.SetField("time","%s" % (sdsvalue))
                feature.SetField("location",sds[0])
                lyr.CreateFeature(feature)

        if timeMetadata.endswith(","):
            timeMetadata = re.sub(r",$","",timeMetadata)
        if timeMetadata.startswith(","):
            timeMetadata = re.sub(r"^,","",timeMetadata)

        if timeMetadata:
            logging.info("Setting %s to %s layer" % (timeMetadata, lyrobj.name))

            lyrobj.setMetaData("wms_timeextent", timeMetadata) 
            lyrobj.setMetaData("wms_timeitem", "time") 

            # NOTE: lyrobj.data will not be the wcs definition file
            # anymore, BUT the time index shapefile
            logging.info("Setting layer data to %s" %
                    (os.path.join(tindex,tindex+".shp")))
            lyrobj.data = None
            lyrobj.tileindex = os.path.join(tindex,tindex+".shp")
        else:
            logging.info("No time subset found")