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

"""
***************************************************************************
    SagaAlgorithm.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.                                   *
*                                                                         *
***************************************************************************
"""
from future import standard_library
standard_library.install_aliases()
from builtins import str
from builtins import range


__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__ = '$Format:%H$'

import os
import importlib
from qgis.PyQt.QtCore import QCoreApplication
from qgis.PyQt.QtGui import QIcon
from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.ProcessingConfig import ProcessingConfig
from processing.core.ProcessingLog import ProcessingLog
from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException
from processing.core.parameters import (getParameterFromString,
                                        ParameterExtent,
                                        ParameterRaster,
                                        ParameterVector,
                                        ParameterTable,
                                        ParameterMultipleInput,
                                        ParameterBoolean,
                                        ParameterFixedTable,
                                        ParameterNumber,
                                        ParameterSelection)
from processing.core.outputs import (getOutputFromString,
                                     OutputVector,
                                     OutputRaster)
from processing.tools import dataobjects
from processing.tools.system import getTempFilename, getTempFilenameInTempFolder
from processing.algs.saga.SagaNameDecorator import decoratedAlgorithmName, decoratedGroupName
from . import SagaUtils

pluginPath = os.path.normpath(os.path.join(
    os.path.split(os.path.dirname(__file__))[0], os.pardir))

sessionExportedLayers = {}


class SagaAlgorithm(GeoAlgorithm):

    OUTPUT_EXTENT = 'OUTPUT_EXTENT'

    def __init__(self, descriptionfile):
        GeoAlgorithm.__init__(self)
        self.hardcodedStrings = []
        self.allowUnmatchingGridExtents = False
        self.descriptionFile = descriptionfile
        self.defineCharacteristicsFromFile()
        self._icon = None

    def getCopy(self):
        newone = SagaAlgorithm(self.descriptionFile)
        newone.provider = self.provider
        return newone

    def getIcon(self):
        if self._icon is None:
            self._icon = QIcon(os.path.join(pluginPath, 'images', 'saga.png'))
        return self._icon

    def defineCharacteristicsFromFile(self):
        with open(self.descriptionFile) as lines:
            line = lines.readline().strip('\n').strip()
            self.name = line
            if '|' in self.name:
                tokens = self.name.split('|')
                self.name = tokens[0]
                #cmdname is the name of the algorithm in SAGA, that is, the name to use to call it in the console
                self.cmdname = tokens[1]

            else:
                self.cmdname = self.name
                self.i18n_name = QCoreApplication.translate("SAGAAlgorithm", str(self.name))
            #_commandLineName is the name used in processing to call the algorithm
            #Most of the time will be equal to the cmdname, but in same cases, several processing algorithms
            #call the same SAGA one
            self._commandLineName = self.createCommandLineName(self.name)
            self.name = decoratedAlgorithmName(self.name)
            self.i18n_name = QCoreApplication.translate("SAGAAlgorithm", str(self.name))
            line = lines.readline().strip('\n').strip()
            self.undecoratedGroup = line
            self.group = decoratedGroupName(self.undecoratedGroup)
            self.i18n_group = QCoreApplication.translate("SAGAAlgorithm", self.group)
            line = lines.readline().strip('\n').strip()
            while line != '':
                if line.startswith('Hardcoded'):
                    self.hardcodedStrings.append(line[len('Hardcoded|'):])
                elif line.startswith('Parameter'):
                    self.addParameter(getParameterFromString(line))
                elif line.startswith('AllowUnmatching'):
                    self.allowUnmatchingGridExtents = True
                elif line.startswith('Extent'):
                    # An extent parameter that wraps 4 SAGA numerical parameters
                    self.extentParamNames = line[6:].strip().split(' ')
                    self.addParameter(ParameterExtent(self.OUTPUT_EXTENT,
                                                      'Output extent'))
                else:
                    self.addOutput(getOutputFromString(line))
                line = lines.readline().strip('\n').strip()

    def processAlgorithm(self, progress):
        commands = list()
        self.exportedLayers = {}

        self.preProcessInputs()

        # 1: Export rasters to sgrd and vectors to shp
        # Tables must be in dbf format. We check that.
        for param in self.parameters:
            if isinstance(param, ParameterRaster):
                if param.value is None:
                    continue
                if param.value.endswith('sdat'):
                    param.value = param.value[:-4] + "sgrd"
                elif not param.value.endswith('sgrd'):
                    exportCommand = self.exportRasterLayer(param.value)
                    if exportCommand is not None:
                        commands.append(exportCommand)
            if isinstance(param, ParameterVector):
                if param.value is None:
                    continue
                layer = dataobjects.getObjectFromUri(param.value, False)
                if layer:
                    filename = dataobjects.exportVectorLayer(layer)
                    self.exportedLayers[param.value] = filename
                elif not param.value.endswith('shp'):
                    raise GeoAlgorithmExecutionException(
                        self.tr('Unsupported file format'))
            if isinstance(param, ParameterTable):
                if param.value is None:
                    continue
                table = dataobjects.getObjectFromUri(param.value, False)
                if table:
                    filename = dataobjects.exportTable(table)
                    self.exportedLayers[param.value] = filename
                elif not param.value.endswith('shp'):
                    raise GeoAlgorithmExecutionException(
                        self.tr('Unsupported file format'))
            if isinstance(param, ParameterMultipleInput):
                if param.value is None:
                    continue
                layers = param.value.split(';')
                if layers is None or len(layers) == 0:
                    continue
                if param.datatype == dataobjects.TYPE_RASTER:
                    for i, layerfile in enumerate(layers):
                        if layerfile.endswith('sdat'):
                            layerfile = param.value[:-4] + "sgrd"
                            layers[i] = layerfile
                        elif not layerfile.endswith('sgrd'):
                            exportCommand = self.exportRasterLayer(layerfile)
                            if exportCommand is not None:
                                commands.append(exportCommand)
                        param.value = ";".join(layers)
                elif param.datatype in [dataobjects.TYPE_VECTOR_ANY,
                                        dataobjects.TYPE_VECTOR_LINE,
                                        dataobjects.TYPE_VECTOR_POLYGON,
                                        dataobjects.TYPE_VECTOR_POINT]:
                    for layerfile in layers:
                        layer = dataobjects.getObjectFromUri(layerfile, False)
                        if layer:
                            filename = dataobjects.exportVectorLayer(layer)
                            self.exportedLayers[layerfile] = filename
                        elif not layerfile.endswith('shp'):
                            raise GeoAlgorithmExecutionException(
                                self.tr('Unsupported file format'))

        # 2: Set parameters and outputs
        command = self.undecoratedGroup + ' "' + self.cmdname + '"'
        command += ' ' + ' '.join(self.hardcodedStrings)

        for param in self.parameters:
            if param.value is None:
                continue
            if isinstance(param, (ParameterRaster, ParameterVector, ParameterTable)):
                value = param.value
                if value in list(self.exportedLayers.keys()):
                    command += ' -' + param.name + ' "' \
                        + self.exportedLayers[value] + '"'
                else:
                    command += ' -' + param.name + ' "' + value + '"'
            elif isinstance(param, ParameterMultipleInput):
                s = param.value
                for layer in list(self.exportedLayers.keys()):
                    s = s.replace(layer, self.exportedLayers[layer])
                command += ' -' + param.name + ' "' + s + '"'
            elif isinstance(param, ParameterBoolean):
                if param.value:
                    command += ' -' + param.name.strip() + " true"
                else:
                    command += ' -' + param.name.strip() + " false"
            elif isinstance(param, ParameterFixedTable):
                tempTableFile = getTempFilename('txt')
                with open(tempTableFile, 'w') as f:
                    f.write('\t'.join([col for col in param.cols]) + '\n')
                    values = param.value.split(',')
                    for i in range(0, len(values), 3):
                        s = values[i] + '\t' + values[i + 1] + '\t' + values[i + 2] + '\n'
                        f.write(s)
                command += ' -' + param.name + ' "' + tempTableFile + '"'
            elif isinstance(param, ParameterExtent):
                # 'We have to substract/add half cell size, since SAGA is
                # center based, not corner based
                halfcell = self.getOutputCellsize() / 2
                offset = [halfcell, -halfcell, halfcell, -halfcell]
                values = param.value.split(',')
                for i in range(4):
                    command += ' -' + self.extentParamNames[i] + ' ' \
                        + str(float(values[i]) + offset[i])
            elif isinstance(param, (ParameterNumber, ParameterSelection)):
                command += ' -' + param.name + ' ' + str(param.value)
            else:
                command += ' -' + param.name + ' "' + str(param.value) + '"'

        for out in self.outputs:
            command += ' -' + out.name + ' "' + out.getCompatibleFileName(self) + '"'

        commands.append(command)

        # special treatment for RGB algorithm
        #TODO: improve this and put this code somewhere else
        for out in self.outputs:
            if isinstance(out, OutputRaster):
                filename = out.getCompatibleFileName(self)
                filename2 = filename + '.sgrd'
                if self.cmdname == 'RGB Composite':
                    commands.append('io_grid_image 0 -IS_RGB -GRID:"' + filename2
                                    + '" -FILE:"' + filename + '"')

        # 3: Run SAGA
        commands = self.editCommands(commands)
        SagaUtils.createSagaBatchJobFileFromSagaCommands(commands)
        loglines = []
        loglines.append(self.tr('SAGA execution commands'))
        for line in commands:
            progress.setCommand(line)
            loglines.append(line)
        if ProcessingConfig.getSetting(SagaUtils.SAGA_LOG_COMMANDS):
            ProcessingLog.addToLog(ProcessingLog.LOG_INFO, loglines)
        SagaUtils.executeSaga(progress)

        if self.crs is not None:
            for out in self.outputs:
                if isinstance(out, (OutputVector, OutputRaster)):
                    prjFile = os.path.splitext(out.getCompatibleFileName(self))[0] + ".prj"
                    with open(prjFile, "w") as f:
                        f.write(self.crs.toWkt())

    def preProcessInputs(self):
        name = self.commandLineName().replace('.', '_')[len('saga:'):]
        try:
            module = importlib.import_module('processing.algs.saga.ext.' + name)
        except ImportError:
            return
        if hasattr(module, 'preProcessInputs'):
            func = getattr(module, 'preProcessInputs')
            func(self)

    def editCommands(self, commands):
        name = self.commandLineName()[len('saga:'):]
        try:
            module = importlib.import_module('processing.algs.saga.ext.' + name)
        except ImportError:
            return commands
        if hasattr(module, 'editCommands'):
            func = getattr(module, 'editCommands')
            return func(commands)
        else:
            return commands

    def getOutputCellsize(self):
        """Tries to guess the cell size of the output, searching for
        a parameter with an appropriate name for it.
        """

        cellsize = 0
        for param in self.parameters:
            if param.value is not None and param.name == 'USER_SIZE':
                cellsize = float(param.value)
                break
        return cellsize

    def exportRasterLayer(self, source):
        global sessionExportedLayers
        if source in sessionExportedLayers:
            exportedLayer = sessionExportedLayers[source]
            if os.path.exists(exportedLayer):
                self.exportedLayers[source] = exportedLayer
                return None
            else:
                del sessionExportedLayers[source]
        layer = dataobjects.getObjectFromUri(source, False)
        if layer:
            filename = str(layer.name())
        else:
            filename = os.path.basename(source)
        validChars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789:'
        filename = ''.join(c for c in filename if c in validChars)
        if len(filename) == 0:
            filename = 'layer'
        destFilename = getTempFilenameInTempFolder(filename + '.sgrd')
        self.exportedLayers[source] = destFilename
        sessionExportedLayers[source] = destFilename
        return 'io_gdal 0 -TRANSFORM 1 -RESAMPLING 3 -GRIDS "' + destFilename + '" -FILES "' + source + '"'

    def checkParameterValuesBeforeExecuting(self):
        """
        We check that there are no multiband layers, which are not
        supported by SAGA, and that raster layers have the same grid extent
        """
        extent = None
        for param in self.parameters:
            files = []
            if isinstance(param, ParameterRaster):
                files = [param.value]
            elif (isinstance(param, ParameterMultipleInput) and
                    param.datatype == ParameterMultipleInput.TYPE_RASTER):
                if param.value is not None:
                    files = param.value.split(";")
            for f in files:
                layer = dataobjects.getObjectFromUri(f)
                if layer is None:
                    continue
                if layer.bandCount() > 1:
                    return self.tr('Input layer %s has more than one band.\n'
                                   'Multiband layers are not supported by SAGA' % str(layer.name()))
                if not self.allowUnmatchingGridExtents:
                    if extent is None:
                        extent = (layer.extent(), layer.height(), layer.width())
                    else:
                        extent2 = (layer.extent(), layer.height(), layer.width())
                        if extent != extent2:
                            return self.tr("Input layers do not have the same grid extent.")

    def createCommandLineName(self, name):
        validChars = \
            'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789:'
        return 'saga:' + ''.join(c for c in name if c in validChars).lower()

    def commandLineName(self):
        return self._commandLineName
