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

"""
***************************************************************************
    merge.py
    ---------------------
    Date                 : October 2014
    Copyright            : (C) 2014 by Radoslaw Guzinski
    Email                : rmgu at dhi-gras 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__ = 'Radoslaw Guzinski'
__date__ = 'October 2014'
__copyright__ = '(C) 2014, Radoslaw Guzinski'

# This will get replaced with a git SHA1 when you do a git archive

__revision__ = '$Format:%H$'


from processing.algs.gdal.GdalAlgorithm import GdalAlgorithm
from processing.core.outputs import OutputRaster
from processing.core.parameters import ParameterBoolean
from processing.core.parameters import ParameterMultipleInput
from processing.core.parameters import ParameterSelection
from processing.tools.system import *
from processing.algs.gdal.GdalUtils import GdalUtils
import os

class buildvrt(GdalAlgorithm):

    INPUT = 'INPUT'
    OUTPUT = 'OUTPUT'
    RESOLUTION = 'RESOLUTION'
    SEPARATE = 'SEPARATE'
    PROJ_DIFFERENCE = 'PROJ_DIFFERENCE'

    RESOLUTION_OPTIONS = ['average', 'highest', 'lowest']

    def defineCharacteristics(self):
        self.name = 'Build Virtual Raster'
        self.group = '[GDAL] Miscellaneous'
        self.addParameter(ParameterMultipleInput(buildvrt.INPUT, 'Input layers', ParameterMultipleInput.TYPE_RASTER))
        self.addParameter(ParameterSelection(buildvrt.RESOLUTION, 'Resolution', buildvrt.RESOLUTION_OPTIONS, 0))
        self.addParameter(ParameterBoolean(buildvrt.SEPARATE, 'Layer stack', True))
        self.addParameter(ParameterBoolean(buildvrt.PROJ_DIFFERENCE, 'Allow projection difference', False))
        self.addOutput(OutputRaster(buildvrt.OUTPUT, 'Output layer'))

    def processAlgorithm(self, progress):
        arguments = []
        arguments.append('-resolution')
        arguments.append(self.RESOLUTION_OPTIONS[self.getParameterValue(self.RESOLUTION)])
        if self.getParameterValue(buildvrt.SEPARATE):
            arguments.append('-separate')
        if self.getParameterValue(buildvrt.PROJ_DIFFERENCE):
            arguments.append('-allow_projection_difference')
        # Always write input files to a text file in case there are many of them and the
        # length of the command will be longer then allowed in command prompt
        listFile = os.path.join(tempFolder(), 'buildvrtInputFiles.txt')
        with open(listFile, 'w') as f:
            f.write(self.getParameterValue(buildvrt.INPUT).replace(';', '\n'))
        arguments.append('-input_file_list')
        arguments.append(listFile)
        out = self.getOutputValue(buildvrt.OUTPUT)
        # Ideally the file extensions should be limited to just .vrt but I'm not sure how
        # to do it simply so instead a check is performed.
        _, ext = os.path.splitext(out)
        if not ext.lower() == '.vrt':
            out = out.replace(ext, '.vrt')
            self.setOutputValue(self.OUTPUT, out)
        arguments.append(out)


        GdalUtils.runGdal(['gdalbuildvrt', GdalUtils.escapeAndJoin(arguments)], progress)