BilgehanZekiOzaytac-TODO.py

class Todo:
    todos = []
    selectedIndex = None
    FILENAME = "todos.txt"

    def addJob(self, job):
        self.todos.append(job)

    def removeJob(self, index=None):
        self.todos.pop((index or self.selectedIndex) - 1)

    def printJobs(self):
        for i, job in enumerate(self.todos):
            print(f"{i + 1}. {job}")

    def printJob(self, index=None):
        i = (index or self.selectedIndex) - 1
        job = self.todos[i]
        print(f"{i + 1}. {job}")

    def updateJob(self, job, index=None):
        self.todos[(index or self.selectedIndex) - 1] = job

    def printCommands(self):

        if self.selectedIndex:
            self.printJob()
            print("-" * 5)
            print("E. Edit Note")
            print("D. Delete Note")
            print("L. List Notes")

        else:
            self.printJobs()
            print("-" * 5)
            print("A. Add Note")
            print("C. Clear Notes")
            print("S. Save Notes")

        print("-" * 5)
        print("X. Exit")

    def loadJobs(self):
        self.todos = []
        with open(self.FILENAME, "a+") as f:
            for line in f:
                self.todos.append(line.strip())

    def saveJobs(self):
        with open(self.FILENAME, "w+") as f:
            f.writelines("%s\n" % job for job in self.todos)

    def clearJobs(self):
        self.todos = []

    def command(self, cmd):
        if self.selectedIndex:
            if cmd == "e":
                self.updateJob(input("Enter your note: "))
                print("Note updated")
            elif cmd == "d":
                self.removeJob()
                self.selectedIndex = None
            elif cmd == "l":
                self.selectedIndex = None
            elif cmd == "x":
                return True

            else:
                print("Unknown command")
        else:
            if cmd == "a":
                self.addJob(input("Enter your note: "))
            elif cmd == "c":
                self.clearJobs()
            elif cmd == "s":
                self.saveJobs()
            elif cmd.isdigit():
                i = int(cmd)
                if len(self.todos) >= i > 0:
                    self.selectedIndex = i
                else:
                    print("Invalid note number")
            elif cmd == "x":
                return True
            else:
                print("Unknown command or index")
        return False


tl = Todo()
tl.loadJobs()
tl.printCommands()
while not tl.command(input()):
    tl.printCommands()
tl.saveJobs()