#  -*- coding: utf-8 -*-
# *****************************************************************************
# Copyright (c) 2015-2016 by the authors, see LICENSE
#
# 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.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Software Foundation, Inc.,
# 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# Module authors:
#   Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
#
# *****************************************************************************


from secop.datatypes import EnumType, FloatRange, IntRange
from secop.gui.qt import QCheckBox, QLabel, QLineEdit, QMessageBox
from secop.gui.qt import QPushButton as QButton
from secop.gui.qt import QSizePolicy, Qt, QWidget, pyqtSignal, pyqtSlot
from secop.gui.util import loadUi
from secop.lib import formatExtendedStack


class ParameterWidget(QWidget):
    setRequested = pyqtSignal(str, str, object)  # module, parameter, target
    plotRequested = pyqtSignal(str, str)  # module, parameter
    cmdRequested = pyqtSignal(str, str, list)  # module, command, args

    def __init__(self,
                 module,
                 paramcmd,
                 datatype=None,
                 initvalue=None,
                 readonly=True,
                 parent=None):
        super(ParameterWidget, self).__init__(parent)
        self._module = module
        self._paramcmd = paramcmd
        self._datatype = datatype
        self._readonly = readonly

        self._load_ui(initvalue)

    def _load_ui(self, initvalue):
        # load ui file, set initvalue to right widget
        pass

    def updateValue(self, value):
        # async !
        pass


class GenericParameterWidget(ParameterWidget):

    def _load_ui(self, initvalue):
        # using two QLineEdits for current and target value
        loadUi(self, 'parambuttons.ui')

        if self._readonly:
            self.setPushButton.setEnabled(False)
            self.setLineEdit.setEnabled(False)
        else:
            self.setLineEdit.returnPressed.connect(
                self.on_setPushButton_clicked)
        self.updateValue(initvalue)

    @pyqtSlot()
    def on_setPushButton_clicked(self):
        self.setRequested.emit(self._module, self._paramcmd,
                               self.setLineEdit.text())

    def updateValue(self, value):
        self.currentLineEdit.setText(str(value))


class EnumParameterWidget(GenericParameterWidget):

    def _load_ui(self, initvalue):
        # using two QLineEdits for current and target value
        loadUi(self, 'parambuttons_select.ui')

        # transfer allowed settings from datatype to comboBoxes
        self._map = {}  # maps index to EnumMember
        self._revmap = {}  # maps Enum.name + Enum.value to index
        for index, member in enumerate(self._datatype._enum.members):
            self.setComboBox.addItem(member.name, member.value)
            self._map[index] = member
            self._revmap[member.name] = self._revmap[member.value] = index
        if self._readonly:
            self.setLabel.setEnabled(False)
            self.setComboBox.setEnabled(False)
            self.setLabel.setHidden(True)
            self.setComboBox.setHidden(True)
        else:
            self.setComboBox.activated.connect(self.on_setPushButton_clicked)

        self.updateValue(initvalue)

    @pyqtSlot()
    def on_setPushButton_clicked(self):
        member = self._map[self.setComboBox.currentIndex()]
        self.setRequested.emit(self._module, self._paramcmd, member)

    def updateValue(self, value):
        self.currentLineEdit.setText(str(value))


class GenericCmdWidget(ParameterWidget):

    def _load_ui(self, initvalue):
        # using two QLineEdits for current and target value
        loadUi(self, 'cmdbuttons.ui')

        self.cmdLineEdit.setText('')
        self.cmdLineEdit.setEnabled(self.datatype.argument is not None)
        self.cmdLineEdit.returnPressed.connect(
            self.on_cmdPushButton_clicked)

    @pyqtSlot()
    def on_cmdPushButton_clicked(self):
        # wait until command complete before retrying
        # since the command is scheduled async: what if an errot happens?
        # XXX: button stays deactivated upon errors in execution of cmd...
        self.cmdPushButton.setEnabled(False)
        self.cmdRequested.emit(
            self._module,
            self._paramcmd,
            self._datatype.from_string(
                self.cmdLineEdit.text()))

    def updateValue(self, value):
        # open dialog and show value, if any.
        # then re-activate the command button
        self.cmdPushButton.setEnabled(True)


def ParameterView(module,
                  paramcmd,
                  datatype=None,
                  initvalue=None,
                  readonly=True,
                  parent=None):
    # depending on datatype returns an initialized widget fit for display and
    # interaction
    if datatype is not None:
        if datatype.IS_COMMAND:
            return GenericCmdWidget(
                module,
                paramcmd,  # name of command
                datatype,
                initvalue,  # not used for comands
                readonly,  # not used for commands
                parent)
        if isinstance(datatype, EnumType):
            return EnumParameterWidget(
                module,
                paramcmd,  # name of parameter
                datatype,
                initvalue,
                readonly,
                parent)

    return GenericParameterWidget(
        module,
        paramcmd,  # name of parameter
        datatype,
        initvalue,
        readonly,
        parent)