"""
***************************************************************************
    merge.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"

import os

from qgis.PyQt.QtGui import QIcon

from qgis.core import (
    QgsRasterFileWriter,
    QgsProcessing,
    QgsProcessingException,
    QgsProcessingParameterDefinition,
    QgsProcessingParameterMultipleLayers,
    QgsProcessingParameterEnum,
    QgsProcessingParameterString,
    QgsProcessingParameterBoolean,
    QgsProcessingParameterNumber,
    QgsProcessingParameterRasterDestination,
)
from processing.algs.gdal.GdalAlgorithm import GdalAlgorithm
from processing.algs.gdal.GdalUtils import GdalUtils

from processing.tools.system import isWindows

pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]


class merge(GdalAlgorithm):
    INPUT = "INPUT"
    PCT = "PCT"
    SEPARATE = "SEPARATE"
    OPTIONS = "OPTIONS"
    CREATION_OPTIONS = "CREATION_OPTIONS"
    EXTRA = "EXTRA"
    DATA_TYPE = "DATA_TYPE"
    NODATA_INPUT = "NODATA_INPUT"
    NODATA_OUTPUT = "NODATA_OUTPUT"
    OUTPUT = "OUTPUT"

    TYPES = [
        "Byte",
        "Int16",
        "UInt16",
        "UInt32",
        "Int32",
        "Float32",
        "Float64",
        "CInt16",
        "CInt32",
        "CFloat32",
        "CFloat64",
        "Int8",
    ]

    def __init__(self):
        super().__init__()

    def initAlgorithm(self, config=None):
        self.addParameter(
            QgsProcessingParameterMultipleLayers(
                self.INPUT, self.tr("Input layers"), QgsProcessing.SourceType.TypeRaster
            )
        )
        self.addParameter(
            QgsProcessingParameterBoolean(
                self.PCT,
                self.tr("Grab pseudocolor table from first layer"),
                defaultValue=False,
            )
        )
        self.addParameter(
            QgsProcessingParameterBoolean(
                self.SEPARATE,
                self.tr("Place each input file into a separate band"),
                defaultValue=False,
            )
        )

        nodata_param = QgsProcessingParameterNumber(
            self.NODATA_INPUT,
            self.tr("Input pixel value to treat as NoData"),
            type=QgsProcessingParameterNumber.Type.Double,
            defaultValue=None,
            optional=True,
        )
        nodata_param.setFlags(
            nodata_param.flags() | QgsProcessingParameterDefinition.Flag.FlagAdvanced
        )
        self.addParameter(nodata_param)

        nodata_out_param = QgsProcessingParameterNumber(
            self.NODATA_OUTPUT,
            self.tr("Assign specified NoData value to output"),
            type=QgsProcessingParameterNumber.Type.Double,
            defaultValue=None,
            optional=True,
        )
        nodata_out_param.setFlags(
            nodata_out_param.flags()
            | QgsProcessingParameterDefinition.Flag.FlagAdvanced
        )
        self.addParameter(nodata_out_param)

        # backwards compatibility parameter
        # TODO QGIS 4: remove parameter and related logic
        options_param = QgsProcessingParameterString(
            self.OPTIONS,
            self.tr("Additional creation options"),
            defaultValue="",
            optional=True,
        )
        options_param.setFlags(
            options_param.flags() | QgsProcessingParameterDefinition.Flag.Hidden
        )
        options_param.setMetadata({"widget_wrapper": {"widget_type": "rasteroptions"}})
        self.addParameter(options_param)

        creation_options_param = QgsProcessingParameterString(
            self.CREATION_OPTIONS,
            self.tr("Additional creation options"),
            defaultValue="",
            optional=True,
        )
        creation_options_param.setFlags(
            creation_options_param.flags()
            | QgsProcessingParameterDefinition.Flag.FlagAdvanced
        )
        creation_options_param.setMetadata(
            {"widget_wrapper": {"widget_type": "rasteroptions"}}
        )
        self.addParameter(creation_options_param)

        extra_param = QgsProcessingParameterString(
            self.EXTRA,
            self.tr("Additional command-line parameters"),
            defaultValue=None,
            optional=True,
        )
        extra_param.setFlags(
            extra_param.flags() | QgsProcessingParameterDefinition.Flag.FlagAdvanced
        )
        self.addParameter(extra_param)

        self.addParameter(
            QgsProcessingParameterEnum(
                self.DATA_TYPE,
                self.tr("Output data type"),
                self.TYPES,
                allowMultiple=False,
                defaultValue=5,
            )
        )

        self.addParameter(
            QgsProcessingParameterRasterDestination(self.OUTPUT, self.tr("Merged"))
        )

    def name(self):
        return "merge"

    def displayName(self):
        return self.tr("Merge")

    def group(self):
        return self.tr("Raster miscellaneous")

    def groupId(self):
        return "rastermiscellaneous"

    def icon(self):
        return QIcon(os.path.join(pluginPath, "images", "gdaltools", "merge.png"))

    def commandName(self):
        return "gdal_merge"

    def getConsoleCommands(self, parameters, context, feedback, executing=True):
        out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)
        self.setOutputValue(self.OUTPUT, out)

        arguments = []
        if self.parameterAsBoolean(parameters, self.PCT, context):
            arguments.append("-pct")

        if self.parameterAsBoolean(parameters, self.SEPARATE, context):
            arguments.append("-separate")

        if (
            self.NODATA_INPUT in parameters
            and parameters[self.NODATA_INPUT] is not None
        ):
            nodata_input = self.parameterAsDouble(
                parameters, self.NODATA_INPUT, context
            )
            arguments.append("-n")
            arguments.append(str(nodata_input))

        if (
            self.NODATA_OUTPUT in parameters
            and parameters[self.NODATA_OUTPUT] is not None
        ):
            nodata_output = self.parameterAsDouble(
                parameters, self.NODATA_OUTPUT, context
            )
            arguments.append("-a_nodata")
            arguments.append(str(nodata_output))

        data_type = self.parameterAsEnum(parameters, self.DATA_TYPE, context)
        if self.TYPES[data_type] == "Int8" and GdalUtils.version() < 3070000:
            raise QgsProcessingException(
                self.tr("Int8 data type requires GDAL version 3.7 or later")
            )

        arguments.append("-ot " + self.TYPES[data_type])

        output_format = QgsRasterFileWriter.driverForExtension(os.path.splitext(out)[1])
        if not output_format:
            raise QgsProcessingException(self.tr("Output format is invalid"))

        arguments.append("-of")
        arguments.append(output_format)

        options = self.parameterAsString(parameters, self.CREATION_OPTIONS, context)
        # handle backwards compatibility parameter OPTIONS
        if self.OPTIONS in parameters and parameters[self.OPTIONS] not in (None, ""):
            options = self.parameterAsString(parameters, self.OPTIONS, context)
        if options:
            arguments.extend(GdalUtils.parseCreationOptions(options))

        if self.EXTRA in parameters and parameters[self.EXTRA] not in (None, ""):
            extra = self.parameterAsString(parameters, self.EXTRA, context)
            arguments.append(extra)

        arguments.append("-o")
        arguments.append(out)

        # 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
        list_file = GdalUtils.writeLayerParameterToTextFile(
            filename="mergeInputFiles.txt",
            alg=self,
            parameters=parameters,
            parameter_name=self.INPUT,
            context=context,
            quote=True,
            executing=executing,
        )
        arguments.append("--optfile")
        arguments.append(list_file)

        return [
            self.commandName() + merge.command_ext(),
            GdalUtils.escapeAndJoin(arguments),
        ]

    @staticmethod
    def command_ext() -> str:
        """
        Returns the gdal_merge command extension
        """
        if isWindows():
            return ".bat"

        if GdalUtils.version() < 3090000:
            return ".py"

        return ""
