"""
external library imports
"""
import datetime
import time

from datetime import timedelta

"""
django imports
"""
from django.http import  HttpResponseForbidden
from django.utils.timezone import now

"""
regluit imports
"""
from regluit.payment.models import PaymentResponse

class ProcessorError(Exception):
    """An abstraction around payment processor exceptions"""
    def __init__(self, message=None, original_exception=None):
        super(ProcessorError, self).__init__(message)
        self.original_exception = original_exception
        


class BasePaymentRequest:
    '''
       Handles common information incident to payment processing
        
    '''
    
    # Global values for the class
    response = None
    raw_response = None
    errorMessage = None
    status = None
    url = None
            
    def ack( self ):
        return None
        
    def success(self):
        
        if self.errorMessage:
            return False
        else:
            return True 
        
    def error(self):
        if self.errorMessage:
            return True
        else:
            return False
        
    def error_data(self):
        return None
    
    def error_id(self):
        return None
    
    def error_string(self):
        return self.errorMessage
    
    def envelope(self):
        # The envelope is used to store info about this request
        if self.response:
            return str(self.response)
        else:
            return None
      
    def correlation_id(self):
        return None
        
    def timestamp(self):
        return str(datetime.datetime.now())
    
class Processor:
    """a function that returns for the given payment processor"""
    requires_explicit_preapprovals=False
    
    def make_account(self, user=None, token=None):
        """template function for return a payment.Account corresponding to the payment system"""
        return None
    
    def ProcessIPN(self, request):
        return HttpResponseForbidden()
        
  
    class Pay( BasePaymentRequest ):
    
      '''
        The pay function generates a redirect URL to approve the transaction
      '''
        
      def __init__( self, transaction, return_url=None,  amount=None, paymentReason=""):
          self.transaction=transaction
          self.return_url = return_url
          self.amount = amount
          
      def api(self):
          return "null api"
        
      def exec_status( self ):
          return None 
          
      def amount( self ):
          return self.amount
          
      def key( self ):
          return None
    
      def next_url( self ):
          return self.return_url 
      
    class Preapproval(Pay):
        
        def __init__( self, transaction, amount, expiry=None, return_url=None,  paymentReason=""):
          
            # set the expiration date for the preapproval if not passed in.  This is what the paypal library does
            now_val = now()
            if expiry is None:
                expiry = now_val + timedelta( days=settings.PREAPPROVAL_PERIOD )
            transaction.date_authorized = now_val
            transaction.date_expired = expiry
            transaction.save()
              
            # Call into our parent class
            Pay.__init__(self, transaction, return_url=return_url,  amount=amount, paymentReason=paymentReason)
      
      
    class Execute(BasePaymentRequest):
        
        '''
            The Execute function sends an existing token(generated via the URL from the pay operation), and collects
            the money.
        '''
        
        def __init__(self, transaction=None):
            self.transaction = transaction
                
        def api(self):
            return "Base Pay"
        
        def key(self):
            # IN paypal land, our key is updated from a preapproval to a pay key here, just return the existing key
            return self.transaction.pay_key
        
        
    
    class Finish(BasePaymentRequest):
        '''
            The Finish function handles the secondary receiver in a chained payment.  
        '''
        def __init__(self, transaction):
            
            print "Finish"
                
                
    class PaymentDetails(BasePaymentRequest):
        '''
           Get details about executed PAY operation
           
           This api must set the following class variables to work with the code in manager.py
           
           status - one of the global transaction status codes
           transactions -- Not supported for amazon, used by paypal
           
        '''
        def __init__(self, transaction=None):
            self.transaction = transaction
              
                
    
    class CancelPreapproval(BasePaymentRequest):
        '''
            Cancels an exisiting token.  
        '''
        
        def __init__(self, transaction):
            self.transaction = transaction
                
                
    class RefundPayment(BasePaymentRequest):
        
        def __init__(self, transaction):
            self.transaction = transaction
                
                
    
                
                
    class PreapprovalDetails(BasePaymentRequest):
        '''
           Get details about an authorized token
           
           This api must set 4 different class variables to work with the code in manager.py
           
           status - one of the global transaction status codes
           approved - boolean value
           currency - not used in this API, but we can get some more info via other APIs - TODO
           amount - not used in this API, but we can get some more info via other APIs - TODO
           
        '''
        def __init__(self, transaction=None):
            self.transaction = transaction