# -*- coding: utf-8 -*-

"""
***************************************************************************
    nviz.py
    ---------------------
    Date                 : August 2012
    Copyright            : (C) 2012 by Victor Olaya
    Email                : volayaf at gmail dot com
***************************************************************************
*                                                                         *
*   This program is free software; you can redistribute it and/or modify  *
*   it under the terms of the GNU General Public License as published by  *
*   the Free Software Foundation; either version 2 of the License, or     *
*   (at your option) any later version.                                   *
*                                                                         *
***************************************************************************
"""

__author__ = 'Victor Olaya'
__date__ = 'August 2012'
__copyright__ = '(C) 2012, Victor Olaya'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'

from qgis.core import *
from processing.parameters.ParameterMultipleInput import ParameterMultipleInput
from processing.grass.GrassUtils import GrassUtils
from processing.core.GeoAlgorithm import GeoAlgorithm
from PyQt4 import QtGui
from processing.tools.system import *
from processing.parameters.ParameterExtent import ParameterExtent
from processing.parameters.ParameterNumber import ParameterNumber
from processing.parameters.ParameterRaster import ParameterRaster
from processing.tools import dataobjects

class nviz(GeoAlgorithm):

    ELEVATION = "ELEVATION"
    VECTOR = "VECTOR"
    GRASS_REGION_EXTENT_PARAMETER = "GRASS_REGION_PARAMETER"
    GRASS_REGION_CELLSIZE_PARAMETER = "GRASS_REGION_CELLSIZE_PARAMETER"

    def getIcon(self):
        return  QtGui.QIcon(os.path.dirname(__file__) + "/../images/grass.png")

    def defineCharacteristics(self):
        self.name = "nviz"
        self.group = "Visualization(NVIZ)"
        self.addParameter(ParameterMultipleInput(nviz.ELEVATION, "Elevation layers", ParameterMultipleInput.TYPE_RASTER, True))
        self.addParameter(ParameterMultipleInput(nviz.VECTOR, "Vector layers", ParameterMultipleInput.TYPE_VECTOR_ANY, True))
        self.addParameter(ParameterExtent(nviz.GRASS_REGION_EXTENT_PARAMETER, "GRASS region extent"))
        self.addParameter(ParameterNumber(self.GRASS_REGION_CELLSIZE_PARAMETER, "GRASS region cellsize (leave 0 for default)", 0, None, 0.0))

    def processAlgorithm(self, progress):
        commands = []
        vector = self.getParameterValue(self.VECTOR);
        elevation = self.getParameterValue(self.ELEVATION);

        region = str(self.getParameterValue(self.GRASS_REGION_EXTENT_PARAMETER))
        regionCoords = region.split(",")
        command = "g.region "
        command += "n=" + str(regionCoords[3])
        command +=" s=" + str(regionCoords[2])
        command +=" e=" + str(regionCoords[1])
        command +=" w=" + str(regionCoords[0])
        cellsize = self.getParameterValue(self.GRASS_REGION_CELLSIZE_PARAMETER)
        if cellsize:
            command +=" res=" + str(cellsize);
        else:
            command +=" res=" + str(self.getDefaultCellsize())
        commands.append(command)

        command = "nviz"
        if vector:
            layers = vector.split(";")
            for layer in layers:
                cmd, newfilename = self.exportVectorLayer(layer)
                commands.append(cmd)
                vector = vector.replace(layer, newfilename)
            command += (" vector=" + vector.replace(";", ","))
        if elevation:
            layers = elevation.split(";")
            for layer in layers:
                cmd, newfilename = self.exportRasterLayer(layer)
                commands.append(cmd)
                elevation = elevation.replace(layer, newfilename)
            command += (" elevation=" + elevation.replace(";", ","))
        if elevation is None and vector is None:
            command += " -q"
        commands.append(command)
        GrassUtils.createTempMapset();
        GrassUtils.executeGrass(commands, progress)

    def getTempFilename(self):
        filename =  "tmp" + str(time.time()).replace(".","") + str(getNumExportedLayers())
        return filename

    def exportVectorLayer(self,layer):
        destFilename = self.getTempFilename()
        command = "v.in.ogr"
        command += " min_area=-1"
        command +=" dsn=\"" + os.path.dirname(layer) + "\""
        command +=" layer=" + os.path.basename(layer)[:-4]
        command +=" output=" + destFilename;
        command +=" --overwrite -o"
        return command, destFilename

    def exportRasterLayer(self, layer):
        destFilename = self.getTempFilename()
        command = "r.in.gdal"
        command +=" input=\"" + layer + "\""
        command +=" band=1"
        command +=" out=" + destFilename;
        command +=" --overwrite -o"
        return command, destFilename

    def getDefaultCellsize(self):
        cellsize = 0
        for param in self.parameters:
            if param.value:
                if isinstance(param, ParameterRaster):
                    if isinstance(param.value, QgsRasterLayer):
                        layer = param.value
                    else:
                        layer = dataobjects.getObjectFromUri(param.value)
                    cellsize = max(cellsize, (layer.extent().xMaximum() - layer.extent().xMinimum())/layer.width())

                elif isinstance(param, ParameterMultipleInput):
                    layers = param.value.split(";")
                    for layername in layers:
                        layer = dataobjects.getObjectFromUri(layername)
                        if isinstance(layer, QgsRasterLayer):
                            cellsize = max(cellsize, (layer.extent().xMaximum() - layer.extent().xMinimum())/layer.width())

        if cellsize == 0:
            cellsize = 1
        return cellsize