from PySide2 import QtCore, QtGui, QtWidgets

from datetime import datetime


class Report(QtWidgets.QDialog):
    def __init__(self, parent, *args, **kwargs):
        super().__init__(parent, *args, **kwargs)
        self._report = None
        self._report_data = None
        self._changing_items = False

        self.setWindowTitle("Report")

        self.tableWidget = QtWidgets.QTableWidget()
        self.tableWidget.verticalHeader().hide()
        self.tableWidget.setColumnCount(3)
        self.tableWidget.setHorizontalHeaderLabels(["Task", "Start time", "Duration"])
        self.tableWidget.cellChanged.connect(self.cell_changed)
        self.header = QtWidgets.QHeaderView(QtCore.Qt.Orientation.Horizontal)
        self.tableWidget.setHorizontalHeader(self.header)

        self.previous_button = QtWidgets.QPushButton()
        self.previous_button.setText("Previous")
        self.previous_button.setIcon(QtGui.QIcon.fromTheme("arrow-left"))
        self.previous_button.pressed.connect(self.previous)

        self.next_button = QtWidgets.QPushButton()
        self.next_button.setText("Next")
        self.next_button.setIcon(QtGui.QIcon.fromTheme("arrow-right"))
        self.next_button.pressed.connect(self.next)

        del_button = QtWidgets.QPushButton()
        del_button.setText("Delete item")
        del_button.setIcon(QtGui.QIcon.fromTheme("list-remove"))
        del_button.pressed.connect(self.del_log)

        ok_button = QtWidgets.QPushButton()
        ok_button.setText("OK")
        ok_button.setIcon(QtGui.QIcon.fromTheme("dialog-ok-apply"))
        ok_button.pressed.connect(self._accept)

        blayout = QtWidgets.QHBoxLayout()
        blayout.addWidget(self.previous_button)
        blayout.addWidget(self.next_button)
        blayout.addWidget(del_button)
        blayout.addWidget(ok_button)

        layout = QtWidgets.QVBoxLayout(self)
        layout.addWidget(self.tableWidget)
        layout.addLayout(blayout)
        self.setLayout(layout)

    def set_data(self, data):
        self._report = data
        self._report_data = self._report.report()
        self.refresh_table()
        self.update_prev_next()

    def refresh_table(self):
        self.tableWidget.setRowCount(len(self._report_data))

        self._changing_items = True
        for row, _ in enumerate(self._report_data):
            item0 = QtWidgets.QTableWidgetItem(self._report_data[row][0])
            self.tableWidget.setItem(row, 0, item0)
            item1 = QtWidgets.QTableWidgetItem(self._report_data[row][1])
            self.tableWidget.setItem(row, 1, item1)
            item2 = QtWidgets.QTableWidgetItem(self._report_data[row][2])
            self.tableWidget.setItem(row, 2, item2)
            item0.setFlags(item0.flags() & QtCore.Qt.ItemIsEnabled)
            item2.setFlags(item2.flags() & QtCore.Qt.ItemIsEnabled)
            if row > len(self._report_data) - 4:
                item1.setFlags(item1.flags() & QtCore.Qt.ItemIsEnabled)
        self._changing_items = False

        self.tableWidget.resizeColumnsToContents()

        min_width = 0
        for i in range(3):
            min_width += self.header.sectionSize(i)
        self.tableWidget.setMinimumWidth(min_width * 1.33)
        self.header.setSectionResizeMode(QtWidgets.QHeaderView.Stretch)
        if self.tableWidget.rowCount() > 4:
            self.tableWidget.setMinimumHeight(min((self.tableWidget.rowCount() + 2) * self.tableWidget.rowHeight(0),
                                                  self.tableWidget.screen().size().height() * 0.8))

    def update_prev_next(self):
        prev, _next = self._report.prev_next_avail()
        self.previous_button.setEnabled(prev)
        self.next_button.setEnabled(_next)

    @QtCore.Slot()
    def del_log(self):
        row = self.tableWidget.currentRow()
        if row > len(self._report_data) - 4:
            return
        del self._report_data[row]
        self.refresh_table()

    @QtCore.Slot()
    def _accept(self):
        self._report.save(self._report_data)
        self.accept()

    @QtCore.Slot()
    def previous(self):
        self._report.save(self._report_data)
        self._report.previous()
        self._report_data = self._report.report()
        self.refresh_table()
        self.update_prev_next()

    @QtCore.Slot()
    def next(self):
        self._report.save(self._report_data)
        self._report.next()
        self._report_data = self._report.report()
        self.refresh_table()
        self.update_prev_next()

    @QtCore.Slot()
    def cell_changed(self, row, column):
        if self._changing_items:
            return
        item = self.tableWidget.item(row, column)
        try:
            new_time = datetime.strptime(item.text(), "%H:%M").time()
        except ValueError:
            item.setText(self._report_data[row][column])
            return
        self._report_data[row][column] = new_time.strftime("%H:%M")
        self._report.save(self._report_data)
        self._report_data = self._report.report()
        self.refresh_table()