import csv
import inspect
import os
from typing import Iterable, List

from PyQt5 import QtCore, QtGui, QtWidgets


class BetterTable(QtWidgets.QTableWidget):

    filepath = os.path.dirname(inspect.getfile(inspect.currentframe()))

    def __init__(self, datafile=None):
        super().__init__()
        self.datafile = datafile
        self.table_headers = []
        self.setSizePolicy(QtWidgets.QSizePolicy.Minimum, QtWidgets.QSizePolicy.Expanding)

    def setItem(self, row: int, column: int, item: str):
        item = QtWidgets.QTableWidgetItem(item)
        super().setItem(row, column, item)

    def setRow(self, rowindex: int, items: Iterable):
        '''
        sets Items to specified row
        '''
        if rowindex >= self.rowCount():
            rowindex = self.rowCount()  # Appending at the end of the rows
        items = list(map(str, items))

        for index in range(self.columnCount()):
            try:
                self.setItem(rowindex, index, items[index])
            except IndexError:
                break  # breaks loop because there are no more items

    def setColumn(self, columnindex: int, items: Iterable):
        '''
        sets items to specified column
        '''
        if columnindex >= self.columnCount():
            columnindex = self.columnCount()  # Appending at the end of the columns
        items = list(map(str, items))

        for index in range(self.rowCount()):
            try:
                self.setItem(index, columnindex, items[index])
            except IndexError:
                break  # breaks loop because there are no more items

    def addRow(self, index: int=None):
        '''Inserts column at the end'''
        if not index:
            index = self.rowCount()
        self.insertRow(index)

    def addColumn(self, index: int=None):
        '''Inserts column at the end'''
        if not index:
            index = self.columnCount()
        # show Dialog which asks for header name
        dialog = HeaderDialog()
        dialog.exec_()
        if dialog.result():
            self.insertColumn(index)

            header = dialog.header.text()
            new_header = QtWidgets.QTableWidgetItem(header)
            self.setHorizontalHeaderItem(index, new_header)
            self.table_headers.append(header)

    def alignColumn(self, columnindex: int, alignment: QtCore.Qt.Alignment):
        '''
        aligns a whole column
        '''
        for index in range(self.rowCount()):
            self.item(index, columnindex).setTextAlignment(alignment)

    def populate(self, data: List[List], headers: List[str]=None):
        '''
        Populates the table from a 2 dimensional array
        '''
        if not headers:
            # set headers to first row of data
            headers = data.pop(0)
        self.table_headers.extend(headers)

        self.setRowCount(len(data))
        if data:
            self.setColumnCount(max([len(row) for row in data]))
        else:
            self.setColumnCount(len(self.table_headers))

        for rowindex, row in enumerate(data):
            self.setRow(rowindex, row)

        self.setHorizontalHeaderLabels(headers)
        self.resizeRowsToContents()
        self.resizeColumnsToContents()

    def getRow(self, rowindex: int) -> List:
        '''
        returns a list with the Items of the row
        '''
        lst = []

        for index in range(self.columnCount()):
            lst.append(self.item(rowindex, index).text())

        return lst

    def getColumn(self, columnindex: int) -> List:
        '''
        returns a list with the Items of the column
        '''
        lst = []

        for index in range(self.rowCount()):
            lst.append(self.item(index, columnindex).text())

        return lst

    def closeEvent(self, event: QtCore.QEvent):
        self.save()
        event.accept()

    def save(self):
        if not bool(self.datafile):
            filedialog = QtWidgets.QFileDialog()
            filedata = filedialog.getSaveFileName(caption="Save file",
                                                directory=self.filepath,
                                                filter="Character Seperated Values(*.csv)"
                                                )

            if filedata[0]:  # bool('') == False / canceling Filedata will return ('','')
                filepath = filedata[0]
        else:
            filepath = os.path.join(self.filepath, self.datafile)

        table = []
        table.append(self.table_headers)

        for rowindex in range(self.rowCount()):
            table.append(self.getRow(rowindex))

        if filepath and table:
            # newline is required because csv will add blank line
            with open(filepath, 'w', newline='', encoding='utf-8') as file:
                writer = csv.writer(file)
                writer.writerows(table)

        else:
            print("either table or filepath is nonexistend")

class HeaderDialog(QtWidgets.QDialog):

    def __init__(self):
        # removes Icon, Help and Close Buttons
        super().__init__(None,
                         QtCore.Qt.CustomizeWindowHint | QtCore.Qt.WindowTitleHint
                        )
        self.setWindowTitle("Spalten Name")
        self.layout = QtWidgets.QHBoxLayout()
        self.buttonBox = QtWidgets.QDialogButtonBox()

        self.desclabel = QtWidgets.QLabel("Spalten Name:")
        self.header = QtWidgets.QLineEdit()

        self.ok_btn = QtWidgets.QPushButton("Ok")
        self.cancel_btn = QtWidgets.QPushButton("Abbrechen")
        self.cancel_btn.setToolTip("Name der Spalte wird zum Index")
        self.buttonBox.addButton(self.ok_btn, self.buttonBox.YesRole)
        self.buttonBox.addButton(self.cancel_btn, self.buttonBox.RejectRole)
        self.ok_btn.clicked.connect(self.accept)
        self.cancel_btn.clicked.connect(self.reject)

        self.layout.addWidget(self.desclabel)
        self.layout.addWidget(self.header)
        self.layout.addWidget(self.buttonBox)

        self.setLayout(self.layout)