import pickle
class Item(object):
    def __init__(self,D,P,DD):
        self.description = D
        self.priority = p
        self.dueDate = DD

    def Update(self, num, info):
        if num == 1 :
            self.description = info
        elif num == 2:
            self.priority = info
        elif num == 3:
            self.dueDate = info
        else:
            print("no valid")


def printList():
    count = 1;
    for i in toDoList:
        print(str(count) + ". " + i.description + " priority is " + i.priority + " due on :" + i.dueDate)
        count += 1;


filename = "todolist2.pickle"

#==== Open To Do List File and Load into memory ===
try:
    f = open(filename, 'rb')
    toDoList = pickle.load(f)
    f.close()
except:
    print("Creating new file..")
    toDoList = []

#=== Run Program ===

runFlag = True
while runFlag:
    #=== Main program selection ===
    response = input("""What do you want to do?
    C: Create a new to do item
    S: Display your to do list
    U: UPdate Item in List
    D: Delete an item from your to do list
    E: Exit program\n>>""")

    #=== Create new to do ===
    if response == "C":

        d = input("What u wan do? \n");
        p = input("What is the priority? \n");
        dd = input("What is the due date? \n");
        newItem = Item(d,p,dd)
        toDoList.append(newItem)
        printList()


    #=== Show to do list ===
    elif response == "S":
        printList()

    #=== Delete To Do Item ===
    elif response == "D":
        i = int(input("What num to delete? \n" ))
        toDoList.pop(i-1)
        printList()

    elif response == "U":
        i = int(input("What item to update? \n"))
        j = int(input("What do you want to update? \n 1. Description \n 2. Priority \n 3. DueDate \n" ))
        info = input("Update to wat? \n" )
        toU = toDoList[i-1]
        toU.Update(j,info)
        toDoList[i-1] = toU
        printList()

    #=== Exit Program ===
    elif response == "E":
        f = open(filename, 'wb')
        pickle.dump(toDoList, f)
        f.close()
        runFlag = False

    else:
        print("Invalid input. Please try again\n")