NEW* Transaction

# import the datetime class used to get today's date
import datetime
 
#  This module defines the Transaction class.
#  A class to represent the data elements and methods required to implement a back account transaction.

class Transaction :
   
   _nextTransaction = 100 # A class variable that hold the number of the next transaction
   DEBUG = False # A class constant
   RESET_TNUMBER = True
   
   # Constructs a transaction.
   #  @param tType: the type of this transaction (String: default is an empty string)
   #  @param amount: the amount of this transaction (Floating point: default is 0.0, must be a positive float)
   #  @param date: the date of the transaction (String: default is an empty string)
   
   def __init__(self, tType = "", amount = 0.0, date = "") :
      if Transaction.DEBUG:
         print ("Creating a new transaction")
      self._tNumber = Transaction._nextTransaction
      Transaction._nextTransaction = Transaction._nextTransaction + 1      
      
      # if the tType is an empty string, prompt for the tType
      if tType == "":
         self.setTType()
      else:
         self._tType = tType

      # if the amount is 0.0, prompt for the tType
      if amount == 0:
         self.setAmount()
      else:   
         self._amount = amount
   
      # if the date is an empty string, set the date to today's date
      if date == "":
         self.setDate()
      else:
         self._date = date
      return

   # Checks an transaction to see if it is equal to the second transaction.
   #  @param other: the transaction your are comparing the first transaction with
   #  @return result: True if this two transaction have the same amount and dates, and tNumber
   
   def __eq__(self, other) :
      result = (self._amount == other._amount) and (self._date == other._date) and (self._tNumber == other._tNumber)
      return result 
    
   # Checks an transaction to see if it is equal to the second transaction.
   #  @param other: the transaction your are comparing the first transaction with
   #  @return result: True if this two transaction have the same amount and dates, and tNumber
   
   def __ne__(self, other) :
      result = (self._amount != other._amount) or (self._date != other._date) or (self._tNumber != other._tNumber)
      return result 
  
   # adds an transaction to the second transaction.
   #  @param other: the transaction your are adding the first transaction to
   #  @return result: the sum of the two transaction prices
   
   def __add__(self, other) :
      return Transaction(amount = (self._amount + other._amount), tType = "Calculated")
   
   # adds an transaction to the second transaction.
   #  @param other: the transaction your are adding the first transaction to
   #  @return result: the sum of the two transaction prices
   
   def __sub__(self, other) :
      return Transaction(self._amount - other._amount, tType = "Calculated")

   # implements the sum() function that will sum a list of the Transactions
   def __radd__(self, other):
      return other + self._amount

   # Define the accessor methods
   
   # getAmount returns the amount of the transaction.
   # @return: The amount of the transaction
   def getAmount(self) :
      return self._amount

   # getDate returns the date of the transaction.
   # @return: The date of the transaction.
   def getDate(self) :
      return self._date

   # getTNumber returns the transaction number of the transaction.
   # @return: The transaction number of the transaction
   def getTNumber(self) :
      return self._tNumber
   
   # getTType returns the transaction type of the transaction.
   # @return: The transaction type of the transaction
   def getTType(self) :
      return self._tType

   # Prints all of the transaction instance variables.
   def printTransaction(self):
      print("Transaction # %d, amount $%.2f, date %s type: %s" % (self._tNumber, self._amount, self._date, self._tType))

   # Define the mutator methods
   
   # Mutator method that sets the transaction type for a transaction
   # @ensure tType: must be Deposit, Withdrawal, Interest, Transfer, or Penalty.
   def setTType(self):
      optionSet = {1, 2, 3, 4, 5}
      option = None
      while option not in optionSet:
         print("Please enter the transaction type")
         print("Select from: ")
         print("   1 - Deposit")
         print("   2 - Withdrawl")
         print("   3 - Interest Payment")
         print("   4 - Transfer")
         print("   5 - Penalty", end = "")
         option = int(input(":"))
      if option == 1:
         tType = "deposit"
      elif option == 2:
         tType = "withdrawl"
      elif option == 3:
         tType = "interest"
      elif option == 4:
         tType = "transfer"
      elif option == 5:
         tType = "penalty"
      else:
         print("Invalid input")
         tType = None
      self._tType = tType
      return

   # Mutator method that sets the amount for a transaction
   # @ensure self._amount >= 0
   def setAmount(self):
      amount = int(input("Please enter an amount (positive) for the transaction:"))
      while amount < 0:
         amount = int(input("Please enter an amount (positive) for the transaction:"))
      self._amount = amount
      return 

   # Mutator method that sets the transaction type for a transaction
   def setDate(self):
      self._date = str(datetime.date.today())
      return