import os
filename = 'addbook.dat'

def readbook(book):
    if os.path.exists(filename):
        store = open(filename,'r')
        for line in store:
            name = line.rstrip()
            entry = store.next().rstrip()
            book[name] = entry
        store.close()


def saveBook(book):
    store = open(filename,'w')
    for name,entry in book.items():
        store.write(name + '\n')
        store.write(entry + '\n')
    store.close()


def getChoice(menu, length):
    print(menu)
    prompt = 'Select a choice(1 - %d): ' % length
    choice = int(input(prompt))
    return choice


def addEntry(book):
    name = input('Enter a name: ')
    entry = input('Enter street, town and phone number: ')
    book[name] = entry


def removeEntry(book):
    name = input('Enter a name: ')
    del (book[name])


def findEntry(book):
    name = input('Enter a name: ')
    if name in book:
        print(name,book[name])
    else:
        print('Sorry, no entry for: ',name)


def main():
    theMenu = '''
    1) Add Entry
    2) Remove Entry
    3) Find Entry
    4) Quit and save
    '''
    theBook = {}
    readBook(theBook)
    choice = getChoice(theMenu, 4)
    while choice != 4:
        if choice == 1:
            addEntry(theBook)
        elif choice == 2:
            removeEntry(theBook)
        elif choice == 3:
            findEntry(theBook)
        else: print( "Invalid choice, try again" )
        choice = getChoice(theMenu, 4)
    saveBook(theBook)

if __name__ == "__main__":
    main()