#python deploy function - copy files from github source to customers s3 bucket
#note, only supporting region us-east-1
from crhelper import CfnResource
import urllib.request
import shutil
import boto3
from botocore.exceptions import ClientError
import mimetypes
import json
from pathlib import Path
import sys
import re

helper = CfnResource()
#create s3 client interface:
s3 = boto3.client('s3')

amazonConnectInstanceAliasToReplace = "myamazonconnect"
tmpfolder = "/tmp/"	#note: "/tmp/" for production

def DoInstanceAliasSubstitution(relativePathAndFileName, amazonConnectInstanceAlias):
	print("DoInstanceAliasSubstitution called for file: " + tmpfolder + relativePathAndFileName + ". doing instance name substitution...")
	print("looking for: " + amazonConnectInstanceAliasToReplace + " to replace with: " + amazonConnectInstanceAlias)

	# 1. read all file lines into an array
	with open(tmpfolder + relativePathAndFileName, mode="r", encoding="utf-8") as f:
		lines = f.readlines()
	print("read in " + str(len(lines)) + " lines")
	# 2. do a search and replace in it for
	#    global static amazonConnectInstanceAliasToReplace and replace it with the value in amazonConnectInstanceAlias
	lines2 = []
	for line in lines:
		if amazonConnectInstanceAliasToReplace.upper() in line.upper():
			print("found a line containing it")
			pattern = re.compile(amazonConnectInstanceAliasToReplace, re.IGNORECASE)		
			tmpline = pattern.sub(amazonConnectInstanceAlias, line)
			lines2.append(tmpline)
		else:
			lines2.append(line)
	print("post processed line count: " + str(len(lines2)))

	print("lets write them back to: " + tmpfolder + relativePathAndFileName)
	# 3. write all the file lines back to /tmp/index.html
	try:
		with open(tmpfolder + relativePathAndFileName, mode="w", encoding="utf-8") as f:
			f.writelines(lines2)
	except:
		print("ERROR: when attempting bucket create with instance alias substitution, error: ")

def dodeployfile(bucketNameTemp, instanceAliasTemp, key, url):
	print('Key: ' + key)
	print('Url: ' + url)
	print('')
	try:
		#lets get the relative folder name we need to write to and create it under /tmp
		pos = key.rfind("/");
		#note: limitation here for now, will only support file downloads 1 folder deep! TODO fix later
		if pos > 0:
			subfolder = key[0:pos]
			if len(subfolder) > 0:
				#make the folder
				p = Path(tmpfolder + subfolder)
				if not(p.exists()):
					p.mkdir()
		#lets try downloading 1 file: "https://raw.githubusercontent.com/plantronics/pdc/master/Amazon%20Connect%20Sample/index.html"
		# Download the file from `url` and save it locally under `file_name`:
		with urllib.request.urlopen(url) as response, open(tmpfolder+key, 'wb') as out_file:
			shutil.copyfileobj(response, out_file)

		if (key == "index.html"):
			DoInstanceAliasSubstitution(key, instanceAliasTemp)

		#now copy to bucket
		content_type = mimetypes.guess_type(tmpfolder+key)[0]
		s3.upload_file(
			tmpfolder+key, bucketNameTemp, key,
			ExtraArgs={'ACL': 'public-read', 'ContentType': content_type}
		)	
	except:
		print("An exception occurred downloading file: " + key + " from bucket: aws-quickstart") 

def dodeletefile(bucketNameTemp, key, url):
	print('Key: ' + key)
	print('Url: ' + url)
	print('')
	try:
		s3.delete_object(Bucket=bucketNameTemp, Key=key)
	
		#lets get the relative folder name we need to write to and create it under /tmp
		pos = key.rfind("/");
		#note: limitation here for now, will only support file downloads 1 folder deep! TODO fix later
		if pos > 0:
			subfolder = key[0:pos]
			if len(subfolder) > 0:
				#delete the folder
				s3.delete_object(Bucket=bucketNameTemp, Key=subfolder)
	except:
		print("An exception occurred deleting file: " + key + " from bucket: " + bucketNameTemp)
		type, value, traceback = sys.exc_info()
		print('Error opening %s: %s' % (value.filename, value.strerror))
		
@helper.create
@helper.update
def deploy_files(event, _):
	print('deploy_files (create/updated) lambda function was invoked.')	
	bucketNameTemp = event['ResourceProperties']['BUCKET_NAME']
	instanceAliasTemp = event['ResourceProperties']['AMAZON_CONNECT_INSTANCE_ALIAS']
	regionNameTemp = 'us-east-1'
	print("bucketNameTemp = " + bucketNameTemp)
	print("instanceAliasTemp = " + instanceAliasTemp)
	print("regionNameTemp = " + regionNameTemp)
	
	#if bucketname has full domain, just chop out the prefix: polystack13-s3bucket-11zoq3n2g7132.s3.amazonaws.com
	pos = bucketNameTemp.find(".");
	if pos > 0:
		bucketNameTemp = bucketNameTemp[0:pos]
		print("bucketNameTemp (prefix) = " + bucketNameTemp)
	
	#load the deploy file list
	s3.download_file(
		"aws-quickstart", "deployfilelist.json", tmpfolder + "deployfilelist.json")
		
	print('deploying to : ' + bucketNameTemp)
	print('substituting alias : ' + instanceAliasTemp)

	numFiles = 0
	#open and iterate the json data in deploy file list
	with open(tmpfolder + "deployfilelist.json") as json_file:
		data = json.load(json_file)
		for deployfile in data["deployfilelist"]:
			for key, url in deployfile.items():
				dodeployfile(bucketNameTemp, instanceAliasTemp, key, url)
				numFiles = numFiles + 1
	
	helper.Data['NumberOfFilesDeployed'] = numFiles

@helper.delete
def delete_files(event, _):
	#todo: make sure you delete all your s3 files here so cloudformation stack can delete
	print('delete_files (delete) lambda function was invoked.')	
	bucketNameTemp = event['ResourceProperties']['BUCKET_NAME']
	instanceAliasTemp = event['ResourceProperties']['AMAZON_CONNECT_INSTANCE_ALIAS']
	regionNameTemp = 'us-east-1'
	print("bucketNameTemp = " + bucketNameTemp)
	print("instanceAliasTemp = " + instanceAliasTemp)
	print("regionNameTemp = " + regionNameTemp)
	
	#if bucketname has full domain, just chop out the prefix: polystack13-s3bucket-11zoq3n2g7132.s3.amazonaws.com
	pos = bucketNameTemp.find(".");
	if pos > 0:
		bucketNameTemp = bucketNameTemp[0:pos]
		print("bucketNameTemp (prefix) = " + bucketNameTemp)
	
	#load the deploy file list
	s3.download_file(
		"aws-quickstart", "deployfilelist.json", tmpfolder + "deployfilelist.json")
		
	print('deleting files in : ' + bucketNameTemp)
	numFiles = 0
	#open and iterate the json data in deploy file list
	with open(tmpfolder + "deployfilelist.json") as json_file:
		data = json.load(json_file)
		for deployfile in data["deployfilelist"]:
			for key, url in deployfile.items():
				dodeletefile(bucketNameTemp, key, url)
				numFiles = numFiles + 1
	
	helper.Data['NumberOfFilesDeployed'] = numFiles

def handler(event, context):
    helper(event, context)