# -*- coding: utf-8 -*-
"""
/***************************************************************************
 DsgManagementToolsDialog
                                 A QGIS plugin
 Brazilian Army Cartographic Production Tools
                             -------------------
        begin                : 2015-08-12
        git sha              : $Format:%H$
        copyright            : (C) 2015 by Brazilian Army - Geographic Service Bureau
        email                : suporte.dsgtools@dsg.eb.mil.br
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/
"""
import os

from qgis.core import QgsCoordinateReferenceSystem, QgsMessageLog

from qgis.core import Qgis
from qgis.PyQt import QtWidgets, uic
from qgis.PyQt.QtCore import pyqtSlot, pyqtSignal, QSettings, Qt
from qgis.PyQt.QtSql import QSqlDatabase
from qgis.PyQt.QtWidgets import QApplication, QMessageBox
from qgis.PyQt.QtGui import QCursor

from ....core.Utils.utils import Utils
from ....core.Factories.SqlFactory.sqlGeneratorFactory import SqlGeneratorFactory
from DsgTools.core.Factories.DbFactory.dbFactory import DbFactory
from DsgTools.core.Factories.DbFactory.abstractDb import AbstractDb
from DsgTools.core.dsgEnums import DsgEnums

FORM_CLASS, _ = uic.loadUiType(
    os.path.join(os.path.dirname(__file__), "connectionWidget.ui")
)


class ConnectionWidget(QtWidgets.QWidget, FORM_CLASS):
    connectionChanged = pyqtSignal()
    problemOccurred = pyqtSignal(str)
    dbChanged = pyqtSignal(AbstractDb)
    styleChanged = pyqtSignal(dict)

    def __init__(self, parent=None):
        """Constructor."""
        super(ConnectionWidget, self).__init__(parent)
        # Set up the user interface from Designer.
        # After setupUI you can access any designer object by doing
        # self.<objectname>, and you can use autoconnect slots - see
        # http://qt-project.org/doc/qt-4.8/designer-using-a-ui-file.html
        # #widgets-and-dialogs-with-auto-connect
        self.setupUi(self)
        self.setInitialState()
        self.serverWidget.populateServersCombo()
        self.serverWidget.abstractDbLoaded.connect(self.getDatabasesFromServer)
        self.serverWidget.clearWidgets.connect(self.clearAll)

    def __del__(self):
        """
        Closes the database
        """
        self.closeDatabase()

    def closeDatabase(self):
        """
        Closes the current database
        """
        if self.abstractDb:
            del self.abstractDb
            self.abstractDb = None

    def clearAll(self):
        """
        Resets the initial state
        """
        self.filename = ""
        self.dbLoaded = False
        self.epsg = 0
        self.crs = None

        self.abstractDb = None
        self.isSpatialite = False
        self.abstractDbFactory = DbFactory()
        self.utils = Utils()

        # populating the postgis combobox
        self.comboBoxPostgis.clear()
        self.spatialiteFileEdit.setReadOnly(True)
        self.postGISCrsEdit.setReadOnly(True)
        self.spatialiteCrsEdit.setReadOnly(True)
        self.edgvSpatialiteVersionEdit.setReadOnly(True)
        self.edgvPostgisVersionEdit.setReadOnly(True)

    def setInitialState(self):
        """
        Sets the initial state
        """
        self.filename = ""
        self.dbLoaded = False
        self.epsg = 0
        self.crs = None

        self.abstractDb = None
        self.isSpatialite = False
        self.tabWidget.setCurrentIndex(0)
        self.abstractDbFactory = DbFactory()
        self.utils = Utils()
        self.serverWidget.serversCombo.setCurrentIndex(0)

        # populating the postgis combobox
        self.comboBoxPostgis.clear()
        self.spatialiteFileEdit.setReadOnly(True)
        self.postGISCrsEdit.setReadOnly(True)
        self.spatialiteCrsEdit.setReadOnly(True)
        self.edgvSpatialiteVersionEdit.setReadOnly(True)
        self.edgvPostgisVersionEdit.setReadOnly(True)

    @pyqtSlot(int)
    def on_comboBoxPostgis_currentIndexChanged(self):
        """
        Updates database information when the combo box changes
        """
        if self.comboBoxPostgis.currentIndex() > 0:
            self.postGISCrsEdit.setText("")
            self.postGISCrsEdit.setReadOnly(True)
            self.edgvPostgisVersionEdit.setText("")
            self.edgvPostgisVersionEdit.setReadOnly(True)
            self.loadDatabase()
            self.connectionChanged.emit()

    @pyqtSlot(bool)
    def on_pushButtonOpenFile_clicked(self):
        """
        Loads a spatialite database
        """
        self.loadDatabase()
        if self.isDBConnected():
            self.connectionChanged.emit()

    @pyqtSlot(int)
    def on_tabWidget_currentChanged(self):
        """
        Changes the tab to work with spatialite or postgis databases
        """
        self.filename = ""
        self.comboBoxPostgis.clear()
        self.dbLoaded = False
        self.epsg = 0
        self.crs = None
        self.dbVersion = ""
        self.serverWidget.serversCombo.setCurrentIndex(0)
        self.spatialiteFileEdit.setReadOnly(True)
        self.spatialiteFileEdit.setText(self.filename)
        self.postGISCrsEdit.setText("")
        self.postGISCrsEdit.setReadOnly(True)
        self.spatialiteCrsEdit.setText("")
        self.spatialiteCrsEdit.setReadOnly(True)
        self.edgvSpatialiteVersionEdit.setText("")
        self.edgvSpatialiteVersionEdit.setReadOnly(True)
        self.edgvPostgisVersionEdit.setText("")
        self.edgvPostgisVersionEdit.setReadOnly(True)
        self.mGroupBox.setTitle(self.tr("Database connection"))

        # Setting the database type
        if self.tabWidget.currentIndex() == 1:
            self.isSpatialite = True
        else:
            self.isSpatialite = False

    def loadDatabase(self):
        """
        Loads the selected database
        """
        self.closeDatabase()
        try:
            if self.isSpatialite:
                self.abstractDb = self.abstractDbFactory.createDbFactory(
                    DsgEnums.DriverSpatiaLite
                )
                self.abstractDb.connectDatabase()
                self.spatialiteFileEdit.setText(self.abstractDb.db.databaseName())
                self.edgvSpatialiteVersionEdit.setText(
                    self.abstractDb.getDatabaseVersion()
                )

            else:
                self.abstractDb = self.abstractDbFactory.createDbFactory(
                    DsgEnums.DriverPostGIS
                )
                (host, port, user, password) = self.serverWidget.getServerParameters()
                dbName = self.comboBoxPostgis.currentText()
                self.abstractDb.connectDatabaseWithParameters(
                    host, port, dbName, user, password
                )
                self.edgvPostgisVersionEdit.setText(
                    self.abstractDb.getDatabaseVersion()
                )
                serverName = self.serverWidget.serversCombo.currentText()
                newText = dbName + self.tr(" on ") + serverName
                self.mGroupBox.setToolTip(newText)
                # self.mGroupBox.setTitle(newText)

            self.abstractDb.checkAndOpenDb()
            self.dbLoaded = True
            self.dbVersion = self.abstractDb.getDatabaseVersion()
            self.abstractDb.checkAndCreateStyleTable()
            self.styles = self.abstractDb.getStyleDict(self.dbVersion)
            self.styleChanged.emit(self.styles)
            self.dbChanged.emit(self.abstractDb)
            if self.dbVersion == "-1":
                self.problemOccurred.emit(
                    self.tr("This is not a valid DsgTools database!")
                )
            else:
                self.setCRS()
        except Exception as e:
            self.problemOccurred.emit(
                self.tr("A problem occurred! Check log for details.")
            )
            QgsMessageLog.logMessage(
                ":".join(e.args), "DSGTools Plugin", Qgis.MessageLevel.Critical
            )

    def setCRS(self):
        """
        Sets the CRS information
        """
        try:
            self.epsg = self.abstractDb.findEPSG()
            if self.epsg == -1:
                self.problemOccurred.emit(
                    self.tr("Coordinate Reference System not set or invalid!")
                )
            else:
                self.crs = QgsCoordinateReferenceSystem(
                    self.epsg, QgsCoordinateReferenceSystem.EpsgCrsId
                )
                if self.isSpatialite:
                    self.spatialiteCrsEdit.setText(self.crs.description())
                    self.spatialiteCrsEdit.setReadOnly(True)
                else:
                    self.postGISCrsEdit.setText(self.crs.description())
                    self.postGISCrsEdit.setReadOnly(True)
        except Exception as e:
            self.problemOccurred.emit(
                self.tr("A problem occurred! Check log for details.")
            )
            QgsMessageLog.logMessage(
                ":".join(e.args), "DSGTools Plugin", Qgis.MessageLevel.Critical
            )

    def isDBConnected(self):
        """
        Checks if the database is already loaded
        """
        return self.dbLoaded

    def getDBVersion(self):
        """
        Gets the database version
        """
        ret = ""
        try:
            ret = self.abstractDb.getDatabaseVersion()
        except Exception as e:
            self.problemOccurred.emit(
                self.tr("A problem occurred! Check log for details.")
            )
            QgsMessageLog.logMessage(
                ":".join(e.args), "DSGTools Plugin", Qgis.MessageLevel.Critical
            )
        return ret

    def getQmlPath(self):
        """
        Gets the QML path
        """
        ret = ""
        try:
            ret = self.abstractDb.getQmlDir()
        except Exception as e:
            self.problemOccurred.emit(
                self.tr("A problem occurred! Check log for details.")
            )
            QgsMessageLog.logMessage(
                ":".join(e.args), "DSGTools Plugin", Qgis.MessageLevel.Critical
            )
        return ret

    def getDatabasesFromServer(self):
        """
        Gets databases from server
        """
        QApplication.setOverrideCursor(QCursor(Qt.CursorShape.WaitCursor))
        try:
            if self.serverWidget.abstractDb:
                dbList = self.serverWidget.abstractDb.getEDGVDbsFromServer(
                    parentWidget=self
                )
                dbList.sort()
                self.comboBoxPostgis.clear()
                self.comboBoxPostgis.addItem(self.tr("Select Database"))
                for db, version in dbList:
                    self.comboBoxPostgis.addItem(db)

            else:
                self.setInitialState()
                QApplication.restoreOverrideCursor()
                return
        except Exception as e:
            QApplication.restoreOverrideCursor()
            QMessageBox.critical(self, self.tr("Critical!"), ":".join(e.args))
            self.setInitialState()
        QApplication.restoreOverrideCursor()
