# -*- coding: utf-8 -*-
"""
/***************************************************************************
 DsgTools
                                 A QGIS plugin
 Brazilian Army Cartographic Production Tools
                              -------------------
        begin                : 2017-01-09
        git sha              : $Format:%H$
        copyright            : (C) 2017 by Philipe Borba - Cartographic Engineer @ Brazilian Army
        email                : borba.philipe@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 QgsMessageLog

# Qt imports
from PyQt4 import QtGui, uic, QtCore
from PyQt4.QtCore import pyqtSlot, pyqtSignal, QSettings, Qt
from PyQt4.QtSql import QSqlQuery

# DSGTools imports
from DsgTools.PostgisCustomization.CustomJSONTools.customJSONBuilder import CustomJSONBuilder

FORM_CLASS, _ = uic.loadUiType(os.path.join(
    os.path.dirname(__file__), 'changeNullityWidget.ui'))

class ChangeNullityWidget(QtGui.QWidget, FORM_CLASS):
    def __init__(self, abstractDb, uiParameterJsonDict = None, parent = None):
        """Constructor."""
        super(self.__class__, self).__init__(parent)
        self.abstractDb = abstractDb
        self.setupUi(self)
        self.jsonBuilder = CustomJSONBuilder()
        self.populateSchemaCombo()
        self.populateFromUiParameterJsonDict(uiParameterJsonDict)
    
    def populateFromUiParameterJsonDict(self, uiParameterJsonDict):
        """
        builds a dict with the following format:
        {
            'schemaComboBox': --current text of schemaComboBox --
            'tableComboBox': --current text of tableComboBox--
            'allAttributesCheckBox': --state of allAttributesCheckBox--
            'allTablesCheckBox': --state of allTablesCheckBox--
            'attributeComboBox': --current text of attributeComboBox--
            'actionComboBoxIdx': --current index of actionComboBox--
        }
        """
        if uiParameterJsonDict:
            if uiParameterJsonDict['allTablesCheckBox']:
                self.allTablesCheckBox.setCheckState(Qt.Checked)
            else:
                schemaIdx = self.schemaComboBox.findText(uiParameterJsonDict['schemaComboBox'], flags = Qt.MatchExactly)
                self.schemaComboBox.setCurrentIndex(schemaIdx)
                tableIdx = self.tableComboBox.findText(uiParameterJsonDict['tableComboBox'], flags = Qt.MatchExactly)
                self.tableComboBox.setCurrentIndex(tableIdx)
                if uiParameterJsonDict['allAttributesCheckBox']:
                    self.allAttributesCheckBox.setCheckState(Qt.Checked)
                else:
                    attributeIdx = self.attributeComboBox.findText(uiParameterJsonDict['attributeComboBox'], flags = Qt.MatchExactly)
                    self.attributeComboBox.setCurrentIndex(attributeIdx)
                self.actionComboBox.setCurrentIndex(uiParameterJsonDict['actionComboBoxIdx'])
    
    def populateSchemaCombo(self):
        self.schemaComboBox.clear()
        self.schemaComboBox.addItem(self.tr('Select a schema'))
        schemaList = self.abstractDb.getGeometricSchemaList()
        for schema in schemaList:
            if schema not in ['views', 'validation']:
                self.schemaComboBox.addItem(schema)

    @pyqtSlot(int)
    def on_schemaComboBox_currentIndexChanged(self, idx):
        if idx == 0:
            self.tableComboBox.clear()
            self.tableComboBox.setEnabled(False)
            self.attributeComboBox.clear()
            self.attributeComboBox.setEnabled(False)
        else:
            schema = self.schemaComboBox.currentText()
            self.tableComboBox.setEnabled(True)
            self.tableComboBox.clear()
            self.tableComboBox.addItem(self.tr('Select a table'))
            tableList = self.abstractDb.getGeometricTableListFromSchema(schema)
            for table in tableList:
                self.tableComboBox.addItem(table)
    
    @pyqtSlot(int)
    def on_tableComboBox_currentIndexChanged(self, idx):
        if idx == 0:
            self.attributeComboBox.clear()
            self.attributeComboBox.setEnabled(False)
        else:
            schema = self.schemaComboBox.currentText()
            tableName = self.tableComboBox.currentText()
            self.attributeComboBox.setEnabled(True)
            self.attributeComboBox.clear()
            self.attributeComboBox.addItem(self.tr('Select an attribute'))
            attributeList = self.abstractDb.getAttributeListFromTable(schema, tableName)
            for attribute in attributeList:
                self.attributeComboBox.addItem(attribute)
    
    @pyqtSlot(int)
    def on_allTablesCheckBox_stateChanged(self, state):
        if state == 0:
            self.allAttributesCheckBox.setEnabled(True)
            self.schemaComboBox.setCurrentIndex(0)
            self.schemaComboBox.setEnabled(True)
        elif state == 2:
            self.allAttributesCheckBox.setEnabled(False)
            self.allAttributesCheckBox.setCheckState(0)
            self.schemaComboBox.setCurrentIndex(0)
            self.schemaComboBox.setEnabled(False)
            
    
    @pyqtSlot(int)
    def on_allAttributesCheckBox_stateChanged(self, state):
        if state == 2:
            self.allTablesCheckBox.setEnabled(False)
            self.allTablesCheckBox.setCheckState(0)
            self.attributeComboBox.setCurrentIndex(0)
            self.attributeComboBox.setEnabled(False)
        if state == 0:
            self.allTablesCheckBox.setEnabled(True)
            self.attributeComboBox.setEnabled(True)
    
    def getTitle(self):
        return self.title
    
    def setTitle(self, title):
        self.title = title
    
    def validate(self):
        if self.actionComboBox.currentIndex() == 0:
            return False
        if self.allTablesCheckBox.checkState() == 2:
            return True
        if self.schemaComboBox.currentIndex() == 0:
            return False
        if self.tableComboBox.currentIndex() == 0:
            return False
        if self.allAttributesCheckBox.checkState() == 2:
            return True
        elif self.attributeComboBox.currentIndex() == 0:
            return False
        return True

    def validateDiagnosis(self):
        invalidatedReason = ''
        if self.schemaComboBox.currentIndex() == 0:
            invalidatedReason += self.tr('A schema must be chosen.\n')
        if self.tableComboBox.currentIndex() == 0:
            invalidatedReason += self.tr('A table must be chosen.\n')
        if self.actionComboBox.currentIndex() == 0:
            invalidatedReason += self.tr('An action be chosen.\n')
        if self.allAttributesCheckBox.checkState() <> 2 and self.attributeComboBox.currentIndex() == 0:
            invalidatedReason += self.tr('An attribute must be chosen.\n')
        return invalidatedReason
    
    def getJSONTag(self):
        if not self.validate():
            raise Exception(self.tr('Error in change nullity customization ')+ self.title + ' : ' + self.validateDiagnosis())
        if self.actionComboBox.currentIndex() == 1:
            notNull = True
        elif self.actionComboBox.currentIndex() == 2:
            notNull = False
        jsonList = []
        if self.allTablesCheckBox.checkState() == 2:
            attributeJsonList = self.abstractDb.getAttributeJsonFromDb()
            for attributeJson in attributeJsonList:
                schema = attributeJson['table_schema']
                table = attributeJson['table_name']
                for attrName in attributeJson['attributelist']:
                    jsonList.append(self.jsonBuilder.buildChangeNullityElement(schema, table, attrName, notNull))
        else:
            schema = self.schemaComboBox.currentText()
            table = self.tableComboBox.currentText()
            if self.allAttributesCheckBox.checkState() == 2:
                attrList = self.abstractDb.getAttributeListFromTable(schema, table)
                for attrName in attrList:
                    jsonList.append(self.jsonBuilder.buildChangeNullityElement(schema, table, attrName, notNull))
            else:
                attrName = self.attributeComboBox.currentText()
                jsonList.append(self.jsonBuilder.buildChangeNullityElement(schema, table, attrName, notNull))
        return jsonList

    def getUiParameterJsonDict(self):
        """
        builds a dict with the following format:
        {
            'schemaComboBox': --current text of schemaComboBox --
            'tableComboBox': --current text of tableComboBox--
            'allAttributesCheckBox': --state of allAttributesCheckBox--
            'allTablesCheckBox': --state of allTablesCheckBox--
            'attributeComboBox': --current text of attributeComboBox--
            'actionComboBoxIdx': --current index of actionComboBox--
        }
        """
        uiParameterJsonDict = dict()
        uiParameterJsonDict['schemaComboBox'] = self.schemaComboBox.currentText()
        uiParameterJsonDict['tableComboBox'] = self.tableComboBox.currentText()
        uiParameterJsonDict['allAttributesCheckBox'] = self.allAttributesCheckBox.isChecked()
        uiParameterJsonDict['allTablesCheckBox'] = self.allTablesCheckBox.isChecked()
        uiParameterJsonDict['attributeComboBox'] = self.attributeComboBox.currentText()
        uiParameterJsonDict['actionComboBoxIdx'] = self.actionComboBox.currentIndex()
        return uiParameterJsonDict