#!/usr/bin/python

# *****  Program to perform various CLI utility functions for Amazon S3 Access
# *****  Written by Gary Morris

import boto3
import argparse
import json
import hashlib
from botocore.client import Config
from pprint import pprint

# Default bucket and region
bucket_name = "vps-testbucket"
region = "us-east-1"

# Function to create client connection object
def client_connect():
    s3client = boto3.client('s3', region)
    return s3client

def delete_objects(key):
    client = client_connect()
    result = client.delete_objects(Bucket=bucket_name, Delete={'Objects': [
                                                                { 'Key': key }
                                                            ] })
    pprint(result)

# Function to return a pre-signed URL given a key.  This is a pre-configured stub for now
def get_presigned_url():
	client = client_connect()
	url = client.generate_presigned_url (
		ClientMethod='get_object',
		Params={
			'Bucket': bucket_name,
			'Key': '063e5e33ba13a97b2f9fe1ae8be524f6-121/20170101/bill10.pdf'
            
			}
		)
        print url	
    	
# List objects given a Prefix        
def get_objects(key):
    client = client_connect()
    response = client.list_objects(Bucket=bucket_name, Prefix=key)
    for content in response["Contents"]:
        print content["Key"]
        
# List buckets        
def list_buckets():
	
	s3 = boto3.resource('s3')
	s3client = boto3.client('s3', region)

	response = s3client.list_buckets()
	for bucket in response["Buckets"]:
		print(bucket['Name'])
	#	for key in bucket.objects.all():
	#		print(key.key)

# Upload a JSON-serialized file of bill data.  customer_id is stubbed and for future should add for validation to prevent overwriting a customer accidentally
def upload_file(filename,customer_id):
	with open(filename) as data_file:
		data = json.load(data_file)
#	pprint(data)	
	
	client = client_connect()

	for customer in data["customers"]:
		
		## Upload file in format s3.upload_file ("tmp.txt", "bucket-name", "key-name",
		##                                         ExtraArgs={"Metadata": {"mykey": "myvalue"}} )
		#

# Key is created using hash of customer_id-client_account_number
		hashval=hashlib.md5(customer["id"] + customer["client_account_number"]).hexdigest() + "-" + customer["id"]
		client.upload_file(customer["filename"], 
			bucket_name, 
			hashval + "/" + customer["statement_date"] + "/" + customer["filename"],
			ExtraArgs={"Metadata": {"customer_id": customer["id"], "current_amount": customer["current_amount"], "client_account_number": customer["client_account_number"]}} )		

## Include tagging, which is required to get bill information for display or filtering
		response = client.put_object_tagging(
			Bucket=bucket_name, 
			Key=hashval + "/" + customer["statement_date"] + "/" + customer["filename"],
			Tagging={
				'TagSet': [
					{
						'Key': 'customer_id',
						'Value': customer["id"]
					},
					{
						'Key': 'current_amount',
						'Value': customer["current_amount"]
					},
					{
						'Key': 'client_account_number',
						'Value': customer["client_account_number"]
					},
					{
						'Key': 'statement_date',
						'Value': customer["statement_date"]
					}
				]
			}
		)
	pprint(response)	

if __name__ == "__main__":

    parser = argparse.ArgumentParser(description='AWS S3 API Utility')
    parser.add_argument('--list', action='store_true', help="List Buckets")
    parser.add_argument('--upload-file', dest='upload_file', help="Upload a file.")
    parser.add_argument('--customer', dest='customer_id', help="Customer ID")
    parser.add_argument('--get-url', dest='get_url', action='store_true', help="Get Presigned URL")
    parser.add_argument('--get-objects', dest='get_objects', action='store_true', help="List Objects, requires --key")
    parser.add_argument('--delete-objects', dest="delete_objects", action='store_true', help="Delete objets, requires --key")
    parser.add_argument('--key', dest='key', help='Lookup Key')

    args = parser.parse_args()

    if (args.list):
        list_buckets()
    elif (args.upload_file):
        upload_file(args.upload_file,args.customer_id)
    elif (args.get_url):
        get_presigned_url()
    elif (args.get_objects):
        get_objects(args.key)
    elif (args.delete_objects):
        delete_objects(args.key)
    else:
        print parser.print_help()