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

"""
***************************************************************************
    BatchInputSelectionPanel.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 pathlib import Path

from qgis.PyQt.QtCore import pyqtSignal, QCoreApplication
from qgis.PyQt.QtWidgets import QWidget, QHBoxLayout, QMenu, QPushButton, QLineEdit, QSizePolicy, QAction, QFileDialog
from qgis.PyQt.QtGui import QCursor

from qgis.core import (QgsMapLayer,
                       QgsRasterLayer,
                       QgsSettings,
                       QgsProject,
                       QgsProcessing,
                       QgsProcessingUtils,
                       QgsProcessingParameterMultipleLayers,
                       QgsProcessingParameterRasterLayer,
                       QgsProcessingParameterVectorLayer,
                       QgsProcessingParameterMeshLayer,
                       QgsProcessingParameterFeatureSource)

from processing.gui.MultipleInputDialog import MultipleInputDialog

from processing.gui.ParameterGuiUtils import getFileFilter
from processing.tools import dataobjects


class BatchInputSelectionPanel(QWidget):

    valueChanged = pyqtSignal()

    def __init__(self, param, row, col, dialog):
        super(BatchInputSelectionPanel, self).__init__(None)
        self.param = param
        self.dialog = dialog
        self.row = row
        self.col = col
        self.horizontalLayout = QHBoxLayout(self)
        self.horizontalLayout.setSpacing(0)
        self.horizontalLayout.setMargin(0)
        self.text = QLineEdit()
        self.text.setObjectName('text')
        self.text.setMinimumWidth(300)
        self.setValue('')
        self.text.editingFinished.connect(self.textEditingFinished)
        self.text.setSizePolicy(QSizePolicy.Expanding,
                                QSizePolicy.Expanding)
        self.horizontalLayout.addWidget(self.text)
        self.pushButton = QPushButton()
        self.pushButton.setText('…')
        self.pushButton.clicked.connect(self.showPopupMenu)
        self.horizontalLayout.addWidget(self.pushButton)
        self.setLayout(self.horizontalLayout)

    def _panel(self):
        return self.dialog.mainWidget()

    def _table(self):
        return self._panel().tblParameters

    def showPopupMenu(self):
        popupmenu = QMenu()

        if not (isinstance(self.param, QgsProcessingParameterMultipleLayers)
                and self.param.layerType == dataobjects.TYPE_FILE):
            selectLayerAction = QAction(
                QCoreApplication.translate('BatchInputSelectionPanel', 'Select from Open Layers…'), self.pushButton)
            selectLayerAction.triggered.connect(self.showLayerSelectionDialog)
            popupmenu.addAction(selectLayerAction)

        selectFileAction = QAction(
            QCoreApplication.translate('BatchInputSelectionPanel', 'Select Files…'), self.pushButton)
        selectFileAction.triggered.connect(self.showFileSelectionDialog)
        popupmenu.addAction(selectFileAction)

        selectDirectoryAction = QAction(
            QCoreApplication.translate('BatchInputSelectionPanel', 'Select Directory…'), self.pushButton)
        selectDirectoryAction.triggered.connect(self.showDirectorySelectionDialog)
        popupmenu.addAction(selectDirectoryAction)

        popupmenu.exec_(QCursor.pos())

    def showLayerSelectionDialog(self):
        layers = []
        if (isinstance(self.param, QgsProcessingParameterRasterLayer)
            or (isinstance(self.param, QgsProcessingParameterMultipleLayers) and
                self.param.layerType() == QgsProcessing.TypeRaster)):
            layers = QgsProcessingUtils.compatibleRasterLayers(QgsProject.instance())
        elif isinstance(self.param, QgsProcessingParameterVectorLayer):
            layers = QgsProcessingUtils.compatibleVectorLayers(QgsProject.instance())
        elif (isinstance(self.param, QgsProcessingParameterMeshLayer)
              or (isinstance(self.param, QgsProcessingParameterMultipleLayers) and
                  self.param.layerType() == QgsProcessing.TypeMesh)):
            layers = QgsProcessingUtils.compatibleMeshLayers(QgsProject.instance())
        else:
            datatypes = [QgsProcessing.TypeVectorAnyGeometry]
            if isinstance(self.param, QgsProcessingParameterFeatureSource):
                datatypes = self.param.dataTypes()
            elif isinstance(self.param, QgsProcessingParameterMultipleLayers):
                datatypes = [self.param.layerType()]

            if QgsProcessing.TypeVectorAnyGeometry not in datatypes:
                layers = QgsProcessingUtils.compatibleVectorLayers(QgsProject.instance(), datatypes)
            else:
                layers = QgsProcessingUtils.compatibleVectorLayers(QgsProject.instance())

        dlg = MultipleInputDialog([layer.name() for layer in layers])
        dlg.exec_()

        def generate_layer_id(layer):
            # prefer layer name if unique
            if len([l for l in layers if l.name().lower() == layer.name().lower()]) == 1:
                return layer.name()
            else:
                # otherwise fall back to layer id
                return layer.id()

        if dlg.selectedoptions is not None:
            selected = dlg.selectedoptions
            if len(selected) == 1:
                self.setValue(generate_layer_id(layers[selected[0]]))
            else:
                if isinstance(self.param, QgsProcessingParameterMultipleLayers):
                    self.text.setText(';'.join(layers[idx].id() for idx in selected))
                else:
                    rowdif = len(selected) - (self._table().rowCount() - self.row)
                    for i in range(rowdif):
                        self._panel().addRow()
                    for i, layeridx in enumerate(selected):
                        self._table().cellWidget(i + self.row,
                                                 self.col).setValue(generate_layer_id(layers[layeridx]))

    def showFileSelectionDialog(self):
        self.showFileDialog(seldir=False)

    def showDirectorySelectionDialog(self):
        self.showFileDialog(seldir=True)

    def showFileDialog(self, seldir):
        settings = QgsSettings()
        text = str(self.text.text())
        if os.path.isdir(text):
            path = text
        elif not seldir and os.path.isdir(os.path.dirname(text)):
            path = os.path.dirname(text)
        elif settings.contains('/Processing/LastInputPath'):
            path = str(settings.value('/Processing/LastInputPath'))
        else:
            path = ''

        if not seldir:
            ret, selected_filter = QFileDialog.getOpenFileNames(
                self, self.tr('Select Files'), path, getFileFilter(self.param)
            )
        else:
            ret = QFileDialog.getExistingDirectory(self, self.tr('Select Directory'), path)

        if ret:
            if seldir:
                settings.setValue('/Processing/LastInputPath', ret)

                files = []
                for pp in Path(ret).rglob("*"):
                    if not pp.is_file():
                        continue

                    p = pp.as_posix()

                    if ((isinstance(self.param, QgsProcessingParameterRasterLayer)
                         or (isinstance(self.param, QgsProcessingParameterMultipleLayers) and self.param.layerType() == QgsProcessing.TypeRaster)) and
                            not QgsRasterLayer.isValidRasterFileName(p)):
                        continue

                    files.append(p)

                if not files:
                    return

            else:
                files = list(ret)
                settings.setValue('/Processing/LastInputPath', os.path.dirname(str(files[0])))

            for i, filename in enumerate(files):
                files[i] = dataobjects.getRasterSublayer(filename, self.param)
            if len(files) == 1:
                self.text.setText(files[0])
                self.textEditingFinished()
            else:
                if isinstance(self.param, QgsProcessingParameterMultipleLayers):
                    self.text.setText(';'.join(str(f) for f in files))
                else:
                    rowdif = len(files) - (self._table().rowCount() - self.row)
                    for i in range(rowdif):
                        self._panel().addRow()
                    for i, f in enumerate(files):
                        self._table().cellWidget(i + self.row,
                                                 self.col).setValue(f)

    def textEditingFinished(self):
        self._value = self.text.text()
        self.valueChanged.emit()

    def getValue(self):
        return self._value if self._value else None

    def setValue(self, value):
        self._value = value
        if isinstance(value, QgsMapLayer):
            self.text.setText(value.name())
        else:  # should be basestring
            self.text.setText(value)
        self.valueChanged.emit()
