# -*- coding: utf-8 -*-

# Copyright (c) 2010 - 2021 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing the chat dialog.
"""

from PyQt5.QtCore import Qt, pyqtSlot, pyqtSignal, QDateTime, QPoint, QFileInfo
from PyQt5.QtGui import QColor
from PyQt5.QtWidgets import QWidget, QListWidgetItem, QMenu, QApplication

from E5Gui.E5Application import e5App
from E5Gui import E5MessageBox, E5FileDialog

from Globals import recentNameHosts

from .CooperationClient import CooperationClient

from .Ui_ChatWidget import Ui_ChatWidget

import Preferences
import Utilities
import UI.PixmapCache


class ChatWidget(QWidget, Ui_ChatWidget):
    """
    Class implementing the chat dialog.
    
    @signal connected(connected) emitted to signal a change of the connected
            state (bool)
    @signal editorCommand(hashStr, filename, message) emitted when an editor
            command has been received (string, string, string)
    @signal shareEditor(share) emitted to signal a share is requested (bool)
    @signal startEdit() emitted to start a shared edit session
    @signal sendEdit() emitted to send a shared edit session
    @signal cancelEdit() emitted to cancel a shared edit session
    """
    connected = pyqtSignal(bool)
    editorCommand = pyqtSignal(str, str, str)
    
    shareEditor = pyqtSignal(bool)
    startEdit = pyqtSignal()
    sendEdit = pyqtSignal()
    cancelEdit = pyqtSignal()
    
    def __init__(self, ui, port=-1, parent=None):
        """
        Constructor
        
        @param ui reference to the user interface object (UserInterface)
        @param port port to be used for the cooperation server (integer)
        @param parent reference to the parent widget (QWidget)
        """
        super(ChatWidget, self).__init__(parent)
        self.setupUi(self)
        
        self.shareButton.setIcon(
            UI.PixmapCache.getIcon("sharedEditDisconnected"))
        self.startEditButton.setIcon(
            UI.PixmapCache.getIcon("sharedEditStart"))
        self.sendEditButton.setIcon(
            UI.PixmapCache.getIcon("sharedEditSend"))
        self.cancelEditButton.setIcon(
            UI.PixmapCache.getIcon("sharedEditCancel"))
        
        self.__ui = ui
        self.__client = CooperationClient(self)
        self.__myNickName = self.__client.nickName()
        
        self.__initChatMenu()
        self.__initUsersMenu()
        
        self.messageEdit.returnPressed.connect(self.__handleMessage)
        self.sendButton.clicked.connect(self.__handleMessage)
        self.__client.newMessage.connect(self.appendMessage)
        self.__client.newParticipant.connect(self.__newParticipant)
        self.__client.participantLeft.connect(self.__participantLeft)
        self.__client.connectionError.connect(self.__showErrorMessage)
        self.__client.cannotConnect.connect(self.__initialConnectionRefused)
        self.__client.editorCommand.connect(self.__editorCommandMessage)
        
        self.serverButton.setText(self.tr("Start Server"))
        self.serverLed.setColor(QColor(Qt.red))
        if port == -1:
            port = Preferences.getCooperation("ServerPort")
        
        self.serverPortSpin.setValue(port)
        
        self.__setConnected(False)
        
        if Preferences.getCooperation("AutoStartServer"):
            self.on_serverButton_clicked()
        
        self.recent = []
        self.__loadHostsHistory()
    
    def __loadHostsHistory(self):
        """
        Private method to load the recently connected hosts.
        """
        self.__recent = []
        Preferences.Prefs.rsettings.sync()
        rh = Preferences.Prefs.rsettings.value(recentNameHosts)
        if rh is not None:
            self.__recent = rh[:20]
            self.hostEdit.clear()
            self.hostEdit.addItems(self.__recent)
            self.hostEdit.clearEditText()
    
    def __saveHostsHistory(self):
        """
        Private method to save the list of recently connected hosts.
        """
        Preferences.Prefs.rsettings.setValue(recentNameHosts, self.__recent)
        Preferences.Prefs.rsettings.sync()
    
    def __setHostsHistory(self, host):
        """
        Private method to remember the given host as the most recent entry.
        
        @param host host entry to remember (string)
        """
        if host in self.__recent:
            self.__recent.remove(host)
        self.__recent.insert(0, host)
        self.__saveHostsHistory()
        self.hostEdit.clear()
        self.hostEdit.addItems(self.__recent)
    
    def __clearHostsHistory(self):
        """
        Private slot to clear the hosts history.
        """
        self.__recent = []
        self.__saveHostsHistory()
        self.hostEdit.clear()
        self.hostEdit.addItems(self.__recent)
    
    def __handleMessage(self):
        """
        Private slot handling the Return key pressed in the message edit.
        """
        text = self.messageEdit.text()
        if text == "":
            return
        
        if text.startswith("/"):
            self.__showErrorMessage(
                self.tr("! Unknown command: {0}\n")
                    .format(text.split()[0]))
        else:
            self.__client.sendMessage(text)
            self.appendMessage(self.__myNickName, text)
        
        self.messageEdit.clear()
    
    def __newParticipant(self, nick):
        """
        Private slot handling a new participant joining.
        
        @param nick nick name of the new participant (string)
        """
        if nick == "":
            return
        
        color = self.chatEdit.textColor()
        self.chatEdit.setTextColor(Qt.gray)
        self.chatEdit.append(
            QDateTime.currentDateTime().toString(Qt.SystemLocaleLongDate) +
            ":")
        self.chatEdit.append(self.tr("* {0} has joined.\n").format(nick))
        self.chatEdit.setTextColor(color)
        
        QListWidgetItem(
            UI.PixmapCache.getIcon(
                "chatUser{0}".format(1 + self.usersList.count() % 6)),
            nick, self.usersList)
        
        if not self.__connected:
            self.__setConnected(True)
        
        if not self.isVisible():
            self.__ui.showNotification(
                UI.PixmapCache.getPixmap("cooperation48"),
                self.tr("New User"), self.tr("{0} has joined.")
                    .format(nick))

    def __participantLeft(self, nick):
        """
        Private slot handling a participant leaving the session.
        
        @param nick nick name of the participant (string)
        """
        if nick == "":
            return
        
        items = self.usersList.findItems(nick, Qt.MatchExactly)
        for item in items:
            self.usersList.takeItem(self.usersList.row(item))
            del item
            
            color = self.chatEdit.textColor()
            self.chatEdit.setTextColor(Qt.gray)
            self.chatEdit.append(
                QDateTime.currentDateTime().toString(Qt.SystemLocaleLongDate) +
                ":")
            self.chatEdit.append(self.tr("* {0} has left.\n").format(nick))
            self.chatEdit.setTextColor(color)
        
        if not self.__client.hasConnections():
            self.__setConnected(False)
        
        if not self.isVisible():
            self.__ui.showNotification(
                UI.PixmapCache.getPixmap("cooperation48"),
                self.tr("User Left"), self.tr("{0} has left.")
                    .format(nick))
    
    def appendMessage(self, from_, message):
        """
        Public slot to append a message to the display.
        
        @param from_ originator of the message (string)
        @param message message to be appended (string)
        """
        if from_ == "" or message == "":
            return
        
        self.chatEdit.append(
            QDateTime.currentDateTime().toString(Qt.SystemLocaleLongDate) +
            " <" + from_ + ">:")
        self.chatEdit.append(message + "\n")
        bar = self.chatEdit.verticalScrollBar()
        bar.setValue(bar.maximum())
        
        if not self.isVisible():
            self.__ui.showNotification(
                UI.PixmapCache.getPixmap("cooperation48"),
                self.tr("Message from <{0}>").format(from_), message)
    
    @pyqtSlot(str)
    def on_hostEdit_editTextChanged(self, host):
        """
        Private slot handling the entry of a host to connect to.
        
        @param host host to connect to (string)
        """
        if not self.__connected:
            self.connectButton.setEnabled(host != "")
    
    def __getConnectionParameters(self):
        """
        Private method to determine the connection parameters.
        
        @return tuple with hostname and port (string, integer)
        """
        hostEntry = self.hostEdit.currentText()
        if "@" in hostEntry:
            host, port = hostEntry.split("@")
            try:
                port = int(port)
            except ValueError:
                port = Preferences.getCooperation("ServerPort")
                self.hostEdit.setEditText("{0}@{1}".format(host, port))
        else:
            host = hostEntry
            port = Preferences.getCooperation("ServerPort")
            self.hostEdit.setEditText("{0}@{1}".format(host, port))
        return host, port
    
    @pyqtSlot()
    def on_connectButton_clicked(self):
        """
        Private slot initiating the connection.
        """
        if not self.__connected:
            host, port = self.__getConnectionParameters()
            self.__setHostsHistory(self.hostEdit.currentText())
            if not self.__client.isListening():
                self.on_serverButton_clicked()
            if self.__client.isListening():
                self.__client.connectToHost(host, port)
                self.__setConnected(True)
        else:
            self.__client.disconnectConnections()
            self.__setConnected(False)
    
    @pyqtSlot()
    def on_clearHostsButton_clicked(self):
        """
        Private slot to clear the hosts list.
        """
        self.__clearHostsHistory()
    
    @pyqtSlot()
    def on_serverButton_clicked(self):
        """
        Private slot to start the server.
        """
        if self.__client.isListening():
            self.__client.close()
            self.serverButton.setText(self.tr("Start Server"))
            self.serverPortSpin.setEnabled(True)
            if (self.serverPortSpin.value() !=
                    Preferences.getCooperation("ServerPort")):
                self.serverPortSpin.setValue(
                    Preferences.getCooperation("ServerPort"))
            self.serverLed.setColor(QColor(Qt.red))
        else:
            res, port = self.__client.startListening(
                self.serverPortSpin.value())
            if res:
                self.serverButton.setText(self.tr("Stop Server"))
                self.serverPortSpin.setValue(port)
                self.serverPortSpin.setEnabled(False)
                self.serverLed.setColor(QColor(Qt.green))
            else:
                self.__showErrorMessage(
                    self.tr("! Server Error: {0}\n").format(
                        self.__client.errorString())
                )
    
    def __setConnected(self, connected):
        """
        Private slot to set the connected state.
        
        @param connected new connected state (boolean)
        """
        if connected:
            self.connectButton.setText(self.tr("Disconnect"))
            self.connectButton.setEnabled(True)
            self.connectionLed.setColor(QColor(Qt.green))
        else:
            self.connectButton.setText(self.tr("Connect"))
            self.connectButton.setEnabled(self.hostEdit.currentText() != "")
            self.connectionLed.setColor(QColor(Qt.red))
            self.on_cancelEditButton_clicked()
            self.shareButton.setChecked(False)
            self.on_shareButton_clicked(False)
        self.__connected = connected
        self.hostEdit.setEnabled(not connected)
        self.serverButton.setEnabled(not connected)
        self.sharingGroup.setEnabled(connected)
        
        if connected:
            vm = e5App().getObject("ViewManager")
            aw = vm.activeWindow()
            if aw:
                self.checkEditorActions(aw)
    
    def __showErrorMessage(self, message):
        """
        Private slot to show an error message.
        
        @param message error message to show (string)
        """
        color = self.chatEdit.textColor()
        self.chatEdit.setTextColor(Qt.red)
        self.chatEdit.append(
            QDateTime.currentDateTime().toString(Qt.SystemLocaleLongDate) +
            ":")
        self.chatEdit.append(message + "\n")
        self.chatEdit.setTextColor(color)
    
    def __initialConnectionRefused(self):
        """
        Private slot to handle the refusal of the initial connection.
        """
        self.__setConnected(False)
    
    def preferencesChanged(self):
        """
        Public slot to handle a change of preferences.
        """
        if not self.__client.isListening():
            self.serverPortSpin.setValue(
                Preferences.getCooperation("ServerPort"))
            if Preferences.getCooperation("AutoStartServer"):
                self.on_serverButton_clicked()
    
    def getClient(self):
        """
        Public method to get a reference to the cooperation client.
        
        @return reference to the cooperation client (CooperationClient)
        """
        return self.__client
    
    def __editorCommandMessage(self, hashStr, fileName, message):
        """
        Private slot to handle editor command messages from the client.
        
        @param hashStr hash of the project (string)
        @param fileName project relative file name of the editor (string)
        @param message command message (string)
        """
        self.editorCommand.emit(hashStr, fileName, message)
        
        from QScintilla.Editor import Editor
        if (message.startswith(Editor.StartEditToken + Editor.Separator) or
                message.startswith(Editor.EndEditToken + Editor.Separator)):
            vm = e5App().getObject("ViewManager")
            aw = vm.activeWindow()
            if aw:
                self.checkEditorActions(aw)
    
    @pyqtSlot(bool)
    def on_shareButton_clicked(self, checked):
        """
        Private slot to share the current editor.
        
        @param checked flag indicating the button state (boolean)
        """
        if checked:
            self.shareButton.setIcon(
                UI.PixmapCache.getIcon("sharedEditConnected"))
        else:
            self.shareButton.setIcon(
                UI.PixmapCache.getIcon("sharedEditDisconnected"))
        self.startEditButton.setEnabled(checked)
        
        self.shareEditor.emit(checked)
    
    @pyqtSlot(bool)
    def on_startEditButton_clicked(self, checked):
        """
        Private slot to start a shared edit session.
        
        @param checked flag indicating the button state (boolean)
        """
        if checked:
            self.sendEditButton.setEnabled(True)
            self.cancelEditButton.setEnabled(True)
            self.shareButton.setEnabled(False)
            self.startEditButton.setEnabled(False)
            
            self.startEdit.emit()
    
    @pyqtSlot()
    def on_sendEditButton_clicked(self):
        """
        Private slot to end a shared edit session and send the changes.
        """
        self.sendEditButton.setEnabled(False)
        self.cancelEditButton.setEnabled(False)
        self.shareButton.setEnabled(True)
        self.startEditButton.setEnabled(True)
        self.startEditButton.setChecked(False)
        
        self.sendEdit.emit()
    
    @pyqtSlot()
    def on_cancelEditButton_clicked(self):
        """
        Private slot to cancel a shared edit session.
        """
        self.sendEditButton.setEnabled(False)
        self.cancelEditButton.setEnabled(False)
        self.shareButton.setEnabled(True)
        self.startEditButton.setEnabled(True)
        self.startEditButton.setChecked(False)
        
        self.cancelEdit.emit()
    
    def checkEditorActions(self, editor):
        """
        Public slot to set action according to an editor's state.
        
        @param editor reference to the editor (Editor)
        """
        shareable, sharing, editing, remoteEditing = editor.getSharingStatus()
        
        self.shareButton.setChecked(sharing)
        if sharing:
            self.shareButton.setIcon(
                UI.PixmapCache.getIcon("sharedEditConnected"))
        else:
            self.shareButton.setIcon(
                UI.PixmapCache.getIcon("sharedEditDisconnected"))
        self.startEditButton.setChecked(editing)
        
        self.shareButton.setEnabled(shareable and not editing)
        self.startEditButton.setEnabled(
            sharing and not editing and not remoteEditing)
        self.sendEditButton.setEnabled(editing)
        self.cancelEditButton.setEnabled(editing)
    
    def __initChatMenu(self):
        """
        Private slot to initialize the chat edit context menu.
        """
        self.__chatMenu = QMenu(self)
        self.__copyChatAct = self.__chatMenu.addAction(
            UI.PixmapCache.getIcon("editCopy"),
            self.tr("Copy"), self.__copyChat)
        self.__chatMenu.addSeparator()
        self.__cutAllChatAct = self.__chatMenu.addAction(
            UI.PixmapCache.getIcon("editCut"),
            self.tr("Cut all"), self.__cutAllChat)
        self.__copyAllChatAct = self.__chatMenu.addAction(
            UI.PixmapCache.getIcon("editCopy"),
            self.tr("Copy all"), self.__copyAllChat)
        self.__chatMenu.addSeparator()
        self.__clearChatAct = self.__chatMenu.addAction(
            UI.PixmapCache.getIcon("editDelete"),
            self.tr("Clear"), self.__clearChat)
        self.__chatMenu.addSeparator()
        self.__saveChatAct = self.__chatMenu.addAction(
            UI.PixmapCache.getIcon("fileSave"),
            self.tr("Save"), self.__saveChat)
        
        self.on_chatEdit_copyAvailable(False)
    
    @pyqtSlot(bool)
    def on_chatEdit_copyAvailable(self, yes):
        """
        Private slot to react to text selection/deselection of the chat edit.
        
        @param yes flag signaling the availability of selected text (boolean)
        """
        self.__copyChatAct.setEnabled(yes)
    
    @pyqtSlot(QPoint)
    def on_chatEdit_customContextMenuRequested(self, pos):
        """
        Private slot to show the context menu for the chat.
        
        @param pos the position of the mouse pointer (QPoint)
        """
        enable = self.chatEdit.toPlainText() != ""
        self.__saveChatAct.setEnabled(enable)
        self.__copyAllChatAct.setEnabled(enable)
        self.__cutAllChatAct.setEnabled(enable)
        self.__chatMenu.popup(self.chatEdit.mapToGlobal(pos))
    
    def __clearChat(self):
        """
        Private slot to clear the contents of the chat display.
        """
        self.chatEdit.clear()
    
    def __saveChat(self):
        """
        Private slot to save the contents of the chat display.
        """
        txt = self.chatEdit.toPlainText()
        if txt:
            fname, selectedFilter = E5FileDialog.getSaveFileNameAndFilter(
                self,
                self.tr("Save Chat"),
                "",
                self.tr("Text Files (*.txt);;All Files (*)"),
                None,
                E5FileDialog.Options(E5FileDialog.DontConfirmOverwrite))
            if fname:
                ext = QFileInfo(fname).suffix()
                if not ext:
                    ex = selectedFilter.split("(*")[1].split(")")[0]
                    if ex:
                        fname += ex
                if QFileInfo(fname).exists():
                    res = E5MessageBox.yesNo(
                        self,
                        self.tr("Save Chat"),
                        self.tr("<p>The file <b>{0}</b> already exists."
                                " Overwrite it?</p>").format(fname),
                        icon=E5MessageBox.Warning)
                    if not res:
                        return
                    fname = Utilities.toNativeSeparators(fname)
                
                try:
                    with open(fname, "w", encoding="utf-8") as f:
                        f.write(txt)
                except OSError as err:
                    E5MessageBox.critical(
                        self,
                        self.tr("Error saving Chat"),
                        self.tr("""<p>The chat contents could not be"""
                                """ written to <b>{0}</b></p>"""
                                """<p>Reason: {1}</p>""") .format(
                            fname, str(err)))
    
    def __copyChat(self):
        """
        Private slot to copy the contents of the chat display to the clipboard.
        """
        self.chatEdit.copy()
    
    def __copyAllChat(self):
        """
        Private slot to copy the contents of the chat display to the clipboard.
        """
        txt = self.chatEdit.toPlainText()
        if txt:
            cb = QApplication.clipboard()
            cb.setText(txt)
    
    def __cutAllChat(self):
        """
        Private slot to cut the contents of the chat display to the clipboard.
        """
        txt = self.chatEdit.toPlainText()
        if txt:
            cb = QApplication.clipboard()
            cb.setText(txt)
        self.chatEdit.clear()
    
    def __initUsersMenu(self):
        """
        Private slot to initialize the users list context menu.
        """
        self.__usersMenu = QMenu(self)
        self.__kickUserAct = self.__usersMenu.addAction(
            UI.PixmapCache.getIcon("chatKickUser"),
            self.tr("Kick User"), self.__kickUser)
        self.__banUserAct = self.__usersMenu.addAction(
            UI.PixmapCache.getIcon("chatBanUser"),
            self.tr("Ban User"), self.__banUser)
        self.__banKickUserAct = self.__usersMenu.addAction(
            UI.PixmapCache.getIcon("chatBanKickUser"),
            self.tr("Ban and Kick User"), self.__banKickUser)
    
    @pyqtSlot(QPoint)
    def on_usersList_customContextMenuRequested(self, pos):
        """
        Private slot to show the context menu for the users list.
        
        @param pos the position of the mouse pointer (QPoint)
        """
        itm = self.usersList.itemAt(pos)
        self.__kickUserAct.setEnabled(itm is not None)
        self.__banUserAct.setEnabled(itm is not None)
        self.__banKickUserAct.setEnabled(itm is not None)
        self.__usersMenu.popup(self.usersList.mapToGlobal(pos))
    
    def __kickUser(self):
        """
        Private slot to disconnect a user.
        """
        itm = self.usersList.currentItem()
        self.__client.kickUser(itm.text())
        
        color = self.chatEdit.textColor()
        self.chatEdit.setTextColor(Qt.darkYellow)
        self.chatEdit.append(
            QDateTime.currentDateTime().toString(Qt.SystemLocaleLongDate) +
            ":")
        self.chatEdit.append(self.tr("* {0} has been kicked.\n").format(
            itm.text().split("@")[0]))
        self.chatEdit.setTextColor(color)
    
    def __banUser(self):
        """
        Private slot to ban a user.
        """
        itm = self.usersList.currentItem()
        self.__client.banUser(itm.text())
        
        color = self.chatEdit.textColor()
        self.chatEdit.setTextColor(Qt.darkYellow)
        self.chatEdit.append(
            QDateTime.currentDateTime().toString(Qt.SystemLocaleLongDate) +
            ":")
        self.chatEdit.append(self.tr("* {0} has been banned.\n").format(
            itm.text().split("@")[0]))
        self.chatEdit.setTextColor(color)
    
    def __banKickUser(self):
        """
        Private slot to ban and kick a user.
        """
        itm = self.usersList.currentItem()
        self.__client.banKickUser(itm.text())
        
        color = self.chatEdit.textColor()
        self.chatEdit.setTextColor(Qt.darkYellow)
        self.chatEdit.append(
            QDateTime.currentDateTime().toString(Qt.SystemLocaleLongDate) +
            ":")
        self.chatEdit.append(
            self.tr("* {0} has been banned and kicked.\n")
                .format(itm.text().split("@")[0]))
        self.chatEdit.setTextColor(color)
    
    def shutdown(self):
        """
        Public method to shut down the cooperation system.
        """
        self.__client.disconnectConnections()
        self.__setConnected(False)
