import json

def menu():
    selection = int(input("1-create file, 2-read file, 3-add to file, 4-quit  "))
    while selection!=1 and selection!=2 and selection!=3 and selection!=4:
        print("You made an invalid selection, please try again")
        selection = int(input("1-create file, 2-read file, 3-add to file, 4-quit  "))
    return selection

def print_menu():
    selection = int(input("1-rivers and countries, 2-rivers, 3-countries  "))
    while selection!=1 and selection!=2 and selection!=3:
        print("You made an invalid selection, please try again")
        selection = int(input("1-rivers and countries, 2-rivers, 3-countries  "))
    return selection

def create(object):
    overwrite = input("You are about to create a new file, existing data will be overwritten (q to quit, any key to continue) ")
    if overwrite !="q":
        with open("rivers.json", "w") as write_file:
            json.dump(object, write_file, indent=4, sort_keys=True)
            print("rivers.json has been created")

def append(new_item):
    with open("rivers.json", "r+") as add_file:
        riverDictionary = json.load(add_file)
        riverDictionary.update(new_item)
        add_file.seek(0)
        json.dump(riverDictionary, add_file, indent=4, sort_keys=True)
        print("Data has been added to rivers.json")

def read():
    try:
        with open("rivers.json") as read_file:
            riverDictionary = json.load(read_file)
    except FileNotFoundError:
        print("The file doesn't exist or cannot be found.")
        print("Please make a different menu selection")      
    else:        
        choice = print_menu()
        if choice==1:
            print_all(riverDictionary)
        elif choice==2:
            print_key(riverDictionary)
        else:
            print_value(riverDictionary)        

def print_all(object):
    print("-----------------Rivers and Countries--------------------------------")
    for key, value in object.items():
       if type(value)==list:
           print(f"The {key.title()} river flows through: ")
           for v in value:
               print("\t\t\t\t",v)
       else:  
           if value.lower()=="united states" or value.lower=="united kingdom":  
               print(f"The {key.title()} river is in the {value.title()}")
           else:
               print(f"The {key.title()} river is in the country of {value.title()}")

def print_key(object):
    print("-----------------Rivers-------------------------------")
    for key in rivers.keys():
       print(key.title())

def print_value(object):
    print("------------------Countries-------------------------------")
    for value in rivers.values():
        if type(value)==list:
           for v in value:
               print(v)
        else:
           print(value)   

def get_key():
    river=input("Enter the name of the river ")
    return river

def get_value():
    multiple=input("Does the river flow through multiple countries (y for yes)? ")
    if multiple=="y" or multiple == "Y":
        country=[]
        new_country=input("Enter the name of a country the river flows through (q to quit)")
        while new_country !="q":
            country.append(new_country)
            new_country=input("Enter the name of a country the river flows through (q to quit)")
    else:
        country = input("Enter the name of the country the river is in ")
    return country
#  initial dictionary
rivers={
    "Danube":["Germany","Austria","Slovakia","Hungary", "Coratia", "Serbia","Romania","Bulgaria", "Moldova", "Ukraine"],
    "Mississippi":"United States",
    "Amazon":["Brazil","Bolivia","Peru","Ecuador","Colombia","Venezuela","Guyana", "Suriname", "French Guiana"]
}
#  manually adding to the dictionary
rivers["Boardman"]="United States"

choice=menu()
while choice != 4:
    if choice == 1:
        create(rivers)
    elif choice == 2:
        read()
    elif choice == 3:
        new_river=get_key()
        new_country=get_value()
        new_dictionary_entry={new_river:new_country}
        append(new_dictionary_entry)
    else:
        print("The option you selected is not available, please try again")        
    choice=menu()