import json
import sys
from PySide6 import QtWidgets, QtGui, QtCore
from Highlighter import Highlighter, Rule
from MainWindow_ui import Ui_MainWindow
from SettingsDialog import SettingsWindow
from TextFormat import TextFormat

def loadSettingsFromFile() -> dict:
    try:
        with open("settings.json", 'r') as f:
            return json.load(f)
    except IOError:
        return None

def saveSettingsToFile(settings: dict) -> None:
    with open("settings.json", 'w') as f:
        json.dump(settings, f, indent=4)

        
class CommandStack:
    def __init__(self) -> None:
        self.__stack = list()
        self.__curIndex = -1

    def add(self, cmd: str) -> None:
        self.__stack.append(cmd)
        self.__curIndex = len(self.__stack) 
        # print("lenght: ", len(self.__stack))

    def hasPrevious(self) -> bool:
        return self.__curIndex > 0

    def hasNext(self) -> bool:
        return (self.__curIndex + 1 < len(self.__stack)) and (len(self.__stack) != 0)

    def getPrevious(self) -> str:
        if len(self.__stack) < 1:
            return ""

        self.__curIndex -= 1
        if self.__curIndex < 0:
            self.__curIndex = 0

        # print("index: ", self.__curIndex)
        return self.__stack[self.__curIndex]

    def getNext(self):
        if len(self.__stack) < 1:
            return ""
        
        self.__curIndex =  min(self.__curIndex + 1, len(self.__stack))
        if self.__curIndex == len(self.__stack):
            return self.__stack[self.__curIndex-1]

        return self.__stack[self.__curIndex]



class MainWindow(QtWidgets.QMainWindow):
    def __init__(self) -> None:
        super().__init__()
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)

        settings = loadSettingsFromFile()
        self.ui_settings = SettingsWindow(settings=settings)

        self.stack = CommandStack()
        self.highlighter = Highlighter(self.ui.txtEdit_mainTerminal.document())

        self.setup()

        self.ruleItemList = []

    def setup(self):
        # header buttons
        self.ui.btn_settings.clicked.connect(self.on_settingsClicked)
        self.ui.btn_connect.clicked.connect(self.on_connectClicked)

        # left side
        self.ui.btn_addPattern.clicked.connect(self.on_addPaternClicked)
        # self.ui.btn_removePattern.clicked.connect(self.on_removePatternClicked)
        self.ui.lst_regex.model().rowsMoved.connect(self.on_item_move)
        
        # right side

        # main side
        self.ui.lineEdit.returnPressed.connect(self.on_returnPressed)
        self.ui.lineEdit.installEventFilter(self)

    def on_connectClicked(self):
        pass

    def on_settingsClicked(self):
        if self.ui_settings.exec():
            self.setTerminalFont(**self.ui_settings.fontsOption["terminal"])
            self.setCommandFont(**self.ui_settings.fontsOption["echo"])

            saveSettingsToFile(self.ui_settings.getSettings())

    def on_addPaternClicked(self):
        item = QtWidgets.QListWidgetItem(f"regex{str(self.ui.lst_regex.count())}")
        item.setFlags(item.flags() | QtGui.Qt.ItemIsUserCheckable)
        item.setCheckState(QtGui.Qt.Unchecked)
        self.ui.lst_regex.addItem(item)

        textFormat = TextFormat()
        regex = QtCore.QRegularExpression()
        rule = Rule(item.text(), True, textFormat, regex)
        self.ruleItemList.append((item, rule))
        print( [ ( i.text(), r.name )for i, r in self.ruleItemList ] )
        self.highlighter.setListOfRules([ r for i, r in self.ruleItemList])

    def on_item_move(self):
        itemList = [self.ui.lst_regex.item(row) for row in range(self.ui.lst_regex.count())]
        self.ruleItemList.sort(key=lambda t: itemList.index(t[0]))
        print( [ ( i.text(), r.name )for i, r in self.ruleItemList ] )
        self.highlighter.setListOfRules([ r for i, r in self.ruleItemList])

    def on_returnPressed(self):
        cmd = self.ui.lineEdit.text()
        self.stack.add(cmd)
        self.ui.txtEdit_mainTerminal.appendPlainText(cmd)
        self.ui.lineEdit.clear()

    def setTerminalFont(self, font_family: str, font_size: str, bold: bool, italic: bool, underline: bool, fg_color: tuple, bg_color: tuple):
        font = list()
        font.append(f'font-family: "{font_family}"')
        font.append(f"font-size: {font_size}pt")
        font.append(f'font-weight: {"bold" if bold else "normal"}')
        font.append(f'font-style: {"italic" if italic else "normal"}')
        font.append(f'text-decoration: {"underline" if underline else "none"}')
        font.append(f"color: rgb({fg_color[0]}, {fg_color[1]}, {fg_color[2]})")
        font.append(f"background-color: rgb({bg_color[0]}, {bg_color[1]}, {bg_color[2]})")
        self.ui.txtEdit_mainTerminal.setStyleSheet(";".join(font))
        self.ui.lbl_examplePattern.setStyleSheet(";".join(font))

    def setCommandFont(self, font_family: str, font_size: str, bold: bool, italic: bool, underline: bool, fg_color: tuple, enable: bool):
        textFormat = TextFormat(font_family, font_size, bold, italic, underline, fg_color)
        regex = QtCore.QRegularExpression(r"^<<[\s]*(.*)")
        rule = Rule("command", enable, textFormat, regex)
        self.highlighter.addRule(rule)
        self.highlighter.rehighlight()

    def eventFilter(self, watched: QtCore.QObject, event: QtCore.QEvent) -> bool:
        if watched is self.ui.lineEdit:
            if event.type() == QtCore.QEvent.KeyPress:
                keyEvent = QtGui.QKeyEvent(event)
                if keyEvent.key() == QtCore.Qt.Key_Up:
                    self.on_upArrow()
                if keyEvent.key() == QtCore.Qt.Key_Down:
                    self.on_downArrow()

        return super().eventFilter(watched, event)

    def on_upArrow(self):
        if self.stack.hasPrevious():
            self.ui.lineEdit.setText(self.stack.getPrevious())

    def on_downArrow(self):
        if self.stack.hasNext():
            self.ui.lineEdit.setText(self.stack.getNext())

def main():
    app = QtWidgets.QApplication(sys.argv)

    window = MainWindow()
    window.show()

    sys.exit(app.exec())

if __name__ == "__main__":
    main()