calculate.py

import json
from collections import defaultdict
from Classes import customer,siteVisit,image,order
from datetime import datetime, timedelta


def Ingest(data,dict):

	for i in data:
		if i['type']=='CUSTOMER':
					
			key=i['key']
			verb=i['verb']
			event_time=i['event_time']
			last_name=i['last_name']
			adr_city=i['adr_city']
			adr_state=i['adr_state']
			cust_details=customer(key,verb,event_time,last_name,adr_city,adr_state)
			if key not in dict:
				dict[key]=defaultdict(list)  #adding customer details to dictionary with list 
			dict[key]['CUSTOMER'].append(cust_details)

		elif i['type']=='SITE_VISIT':
			
			key=i['key']
			verb=i['verb']
			event_time=i['event_time']
			customer_id=i['customer_id']
			tags=i['tags']
			site_details=siteVisit(key,verb,event_time,customer_id,tags)
			dict[customer_id]['SITE_VISIT'].append(site_details) #appending site visit  details to dictionary
	
		elif i['type']=='IMAGE':
			
			key=i['key']
			verb=i['verb']
			event_time=i['event_time']
			customer_id=i['customer_id']
			camera_make=i['camera_make']
			camera_model=i['camera_model']
			image_details=image(key,verb,event_time,customer_id,camera_make,camera_model)
			dict[customer_id]['IMAGE'].append(image_details) #appending image upload details to dictionary 
			
		elif i['type']=='ORDER':
			
			key=i['key']
                	verb=i['verb']
                	event_time=i['event_time']
                	customer_id=i['customer_id']
			total_amount=i['total_amount']
			order_details=order(key,verb,event_time,customer_id,total_amount)
			dict [customer_id]['ORDER'].append(order_details) #appending order details to dictionary
		else:
			print 'Input Type is Wrong'
			exit(1)
	return dict


#Function to claculate top X customers
def topXSimpleLTVCustomers(top_Customer,dict):
	cust_ltv={} #dictionary to hold customer id and LTV value for top X customer
	t=10 
	ltv=0
	
	for c in dict.keys(): #going through the dictionary which has all the details loaded
		
		no_of_visit=0
		total_amount=0
		#total amount spent by customer
		order=dict[c].get('ORDER',None)
		if order is not None:
			for o in order:
				total_amount=total_amount+float(o.total_amount.split(' ')[0].strip())
	
		#total number of visits
		
		visit=dict[c].get('SITE_VISIT',None)
		if visit is not None:
			no_of_visit=len(visit)
		
		#Logic to get the number of weeks
		curr=dict[c].get('CUSTOMER')[0].event_time
		curr = datetime.strptime(curr, '%Y-%m-%dT%H:%M:%S.%fZ').date()
    		first_week =curr - timedelta(days=curr.weekday())#Assuming the given date in the file as start week and taking the starting week of the customer 
		this_week=datetime.now().date()-timedelta(days=datetime.now().date().weekday())#Current week 
		total_weeks=int(abs((first_week-this_week).days))/7 
		if total_weeks==0: #check if visit is current week
			total_weeks=1
 

		#calculating the avaerage part 'a'
		if no_of_visit>0: #checking this inorder to avoid divide by zero error caused by no_of_visit
			avg_cust_amount=total_amount/no_of_visit
			site_visit_per_week=no_of_visit/total_weeks
			a=avg_cust_amount*site_visit_per_week
			ltv=52*a*t
		else:
			ltv=0
		
		cust_ltv[c]=ltv
	
	#sorting the dictionary and printing the top X customers
	result=[]
	if top_Customer >  len(dict):
		print 'X is greater than number of customers in the input file,however printing all the customers in the file'
		top_Customer=len(dict)
	for i in  sorted(cust_ltv,key=cust_ltv.get,reverse=True):
		result.append((i,cust_ltv.get(i)))
	print 'Customer ID     LTV'
	for k in range(0,top_Customer):
		print str(result[k][0])+'                '+ str(result[k][1])