#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Basic interface to Amazon MWS
# Based on http://code.google.com/p/amazon-mws-python
# Extended to include finances object
from __future__ import unicode_literals

import base64
import hashlib
import hmac
import re
from urllib.parse import quote

from erpnext.erpnext_integrations.doctype.amazon_mws_settings import xml_utils

try:
	from xml.etree.ElementTree import ParseError as XMLError
except ImportError:
	from xml.parsers.expat import ExpatError as XMLError

from time import gmtime, strftime

from requests import request
from requests.exceptions import HTTPError

__all__ = [
	'Feeds',
	'Inventory',
	'MWSError',
	'Reports',
	'Orders',
	'Products',
	'Recommendations',
	'Sellers',
	'Finances'
]

# See https://images-na.ssl-images-amazon.com/images/G/01/mwsportal/doc/en_US/bde/MWSDeveloperGuide._V357736853_.pdf page 8
# for a list of the end points and marketplace IDs

MARKETPLACES = {
	"CA": "https://mws.amazonservices.ca", #A2EUQ1WTGCTBG2
	"US": "https://mws.amazonservices.com", #ATVPDKIKX0DER",
	"DE": "https://mws-eu.amazonservices.com", #A1PA6795UKMFR9
	"ES": "https://mws-eu.amazonservices.com", #A1RKKUPIHCS9HS
	"FR": "https://mws-eu.amazonservices.com", #A13V1IB3VIYZZH
	"IN": "https://mws.amazonservices.in", #A21TJRUUN4KGV
	"IT": "https://mws-eu.amazonservices.com", #APJ6JRA9NG5V4
	"UK": "https://mws-eu.amazonservices.com", #A1F83G8C2ARO7P
	"JP": "https://mws.amazonservices.jp", #A1VC38T7YXB528
	"CN": "https://mws.amazonservices.com.cn", #AAHKV2X7AFYLW
	"AE": "	https://mws.amazonservices.ae", #A2VIGQ35RCS4UG
	"MX": "https://mws.amazonservices.com.mx", #A1AM78C64UM0Y8
	"BR": "https://mws.amazonservices.com", #A2Q3Y263D00KWC
}


class MWSError(Exception):
	"""
		Main MWS Exception class
	"""
	# Allows quick access to the response object.
	# Do not rely on this attribute, always check if its not None.
	response = None

def calc_md5(string):
	"""Calculates the MD5 encryption for the given string
	"""
	md = hashlib.md5()
	md.update(string)
	return base64.encodebytes(md.digest()).decode().strip()



def remove_empty(d):
	"""
		Helper function that removes all keys from a dictionary (d),
	that have an empty value.
	"""
	for key in list(d):
		if not d[key]:
			del d[key]
	return d

def remove_namespace(xml):
	xml = xml.decode('utf-8')
	regex = re.compile(' xmlns(:ns2)?="[^"]+"|(ns2:)|(xml:)')
	return regex.sub('', xml)

class DictWrapper(object):
	def __init__(self, xml, rootkey=None):
		self.original = xml
		self._rootkey = rootkey
		self._mydict = xml_utils.xml2dict().fromstring(remove_namespace(xml))
		self._response_dict = self._mydict.get(list(self._mydict)[0], self._mydict)

	@property
	def parsed(self):
		if self._rootkey:
			return self._response_dict.get(self._rootkey)
		else:
			return self._response_dict

class DataWrapper(object):
	"""
		Text wrapper in charge of validating the hash sent by Amazon.
	"""
	def __init__(self, data, header):
		self.original = data
		if 'content-md5' in header:
			hash_ = calc_md5(self.original)
			if header['content-md5'] != hash_:
				raise MWSError("Wrong Contentlength, maybe amazon error...")

	@property
	def parsed(self):
		return self.original

class MWS(object):
	""" Base Amazon API class """

	# This is used to post/get to the different uris used by amazon per api
	# ie. /Orders/2011-01-01
	# All subclasses must define their own URI only if needed
	URI = "/"

	# The API version varies in most amazon APIs
	VERSION = "2009-01-01"

	# There seem to be some xml namespace issues. therefore every api subclass
	# is recommended to define its namespace, so that it can be referenced
	# like so AmazonAPISubclass.NS.
	# For more information see http://stackoverflow.com/a/8719461/389453
	NS = ''

	# Some APIs are available only to either a "Merchant" or "Seller"
	# the type of account needs to be sent in every call to the amazon MWS.
	# This constant defines the exact name of the parameter Amazon expects
	# for the specific API being used.
	# All subclasses need to define this if they require another account type
	# like "Merchant" in which case you define it like so.
	# ACCOUNT_TYPE = "Merchant"
	# Which is the name of the parameter for that specific account type.
	ACCOUNT_TYPE = "SellerId"

	def __init__(self, access_key, secret_key, account_id, region='US', domain='', uri="", version=""):
		self.access_key = access_key
		self.secret_key = secret_key
		self.account_id = account_id
		self.version = version or self.VERSION
		self.uri = uri or self.URI

		if domain:
			self.domain = domain
		elif region in MARKETPLACES:
			self.domain = MARKETPLACES[region]
		else:
			error_msg = "Incorrect region supplied ('%(region)s'). Must be one of the following: %(marketplaces)s" % {
				"marketplaces" : ', '.join(MARKETPLACES.keys()),
				"region" : region,
			}
			raise MWSError(error_msg)

	def make_request(self, extra_data, method="GET", **kwargs):
		"""Make request to Amazon MWS API with these parameters
		"""

		# Remove all keys with an empty value because
		# Amazon's MWS does not allow such a thing.
		extra_data = remove_empty(extra_data)

		params = {
			'AWSAccessKeyId': self.access_key,
			self.ACCOUNT_TYPE: self.account_id,
			'SignatureVersion': '2',
			'Timestamp': self.get_timestamp(),
			'Version': self.version,
			'SignatureMethod': 'HmacSHA256',
		}
		params.update(extra_data)
		request_description = '&'.join(['%s=%s' % (k, quote(params[k], safe='-_.~')) for k in sorted(params)])
		signature = self.calc_signature(method, request_description)
		url = '%s%s?%s&Signature=%s' % (self.domain, self.uri, request_description, quote(signature))
		headers = {'User-Agent': 'python-amazon-mws/0.0.1 (Language=Python)'}
		headers.update(kwargs.get('extra_headers', {}))

		try:
			# Some might wonder as to why i don't pass the params dict as the params argument to request.
			# My answer is, here i have to get the url parsed string of params in order to sign it, so
			# if i pass the params dict as params to request, request will repeat that step because it will need
			# to convert the dict to a url parsed string, so why do it twice if i can just pass the full url :).
			response = request(method, url, data=kwargs.get('body', ''), headers=headers)
			response.raise_for_status()
			# When retrieving data from the response object,
			# be aware that response.content returns the content in bytes while response.text calls
			# response.content and converts it to unicode.
			data = response.content

			# I do not check the headers to decide which content structure to server simply because sometimes
			# Amazon's MWS API returns XML error responses with "text/plain" as the Content-Type.
			try:
				parsed_response = DictWrapper(data, extra_data.get("Action") + "Result")
			except XMLError:
				parsed_response = DataWrapper(data, response.headers)

		except HTTPError as e:
			error = MWSError(str(e))
			error.response = e.response
			raise error

		# Store the response object in the parsed_response for quick access
		parsed_response.response = response
		return parsed_response

	def get_service_status(self):
		"""
			Returns a GREEN, GREEN_I, YELLOW or RED status.
			Depending on the status/availability of the API its being called from.
		"""

		return self.make_request(extra_data=dict(Action='GetServiceStatus'))

	def calc_signature(self, method, request_description):
		"""Calculate MWS signature to interface with Amazon
		"""
		sig_data = method + '\n' + self.domain.replace('https://', '').lower() + '\n' + self.uri + '\n' + request_description
		sig_data = sig_data.encode('utf-8')
		secret_key = self.secret_key.encode('utf-8')
		digest = hmac.new(secret_key, sig_data, hashlib.sha256).digest()
		return base64.b64encode(digest).decode('utf-8')

	def get_timestamp(self):
		"""
			Returns the current timestamp in proper format.
		"""
		return strftime("%Y-%m-%dT%H:%M:%SZ", gmtime())

	def enumerate_param(self, param, values):
		"""
			Builds a dictionary of an enumerated parameter.
			Takes any iterable and returns a dictionary.
			ie.
			enumerate_param('MarketplaceIdList.Id', (123, 345, 4343))
			returns
			{
				MarketplaceIdList.Id.1: 123,
				MarketplaceIdList.Id.2: 345,
				MarketplaceIdList.Id.3: 4343
			}
		"""
		params = {}
		if values is not None:
			if not param.endswith('.'):
				param = "%s." % param
			for num, value in enumerate(values):
				params['%s%d' % (param, (num + 1))] = value
		return params


class Feeds(MWS):
	""" Amazon MWS Feeds API """

	ACCOUNT_TYPE = "Merchant"

	def submit_feed(self, feed, feed_type, marketplaceids=None,
					content_type="text/xml", purge='false'):
		"""
		Uploads a feed ( xml or .tsv ) to the seller's inventory.
		Can be used for creating/updating products on Amazon.
		"""
		data = dict(Action='SubmitFeed',
					FeedType=feed_type,
					PurgeAndReplace=purge)
		data.update(self.enumerate_param('MarketplaceIdList.Id.', marketplaceids))
		md = calc_md5(feed)
		return self.make_request(data, method="POST", body=feed,
								extra_headers={'Content-MD5': md, 'Content-Type': content_type})

	def get_feed_submission_list(self, feedids=None, max_count=None, feedtypes=None,
								processingstatuses=None, fromdate=None, todate=None):
		"""
		Returns a list of all feed submissions submitted in the previous 90 days.
		That match the query parameters.
		"""

		data = dict(Action='GetFeedSubmissionList',
					MaxCount=max_count,
					SubmittedFromDate=fromdate,
					SubmittedToDate=todate,)
		data.update(self.enumerate_param('FeedSubmissionIdList.Id', feedids))
		data.update(self.enumerate_param('FeedTypeList.Type.', feedtypes))
		data.update(self.enumerate_param('FeedProcessingStatusList.Status.', processingstatuses))
		return self.make_request(data)

	def get_submission_list_by_next_token(self, token):
		data = dict(Action='GetFeedSubmissionListByNextToken', NextToken=token)
		return self.make_request(data)

	def get_feed_submission_count(self, feedtypes=None, processingstatuses=None, fromdate=None, todate=None):
		data = dict(Action='GetFeedSubmissionCount',
					SubmittedFromDate=fromdate,
					SubmittedToDate=todate)
		data.update(self.enumerate_param('FeedTypeList.Type.', feedtypes))
		data.update(self.enumerate_param('FeedProcessingStatusList.Status.', processingstatuses))
		return self.make_request(data)

	def cancel_feed_submissions(self, feedids=None, feedtypes=None, fromdate=None, todate=None):
		data = dict(Action='CancelFeedSubmissions',
					SubmittedFromDate=fromdate,
					SubmittedToDate=todate)
		data.update(self.enumerate_param('FeedSubmissionIdList.Id.', feedids))
		data.update(self.enumerate_param('FeedTypeList.Type.', feedtypes))
		return self.make_request(data)

	def get_feed_submission_result(self, feedid):
		data = dict(Action='GetFeedSubmissionResult', FeedSubmissionId=feedid)
		return self.make_request(data)

class Reports(MWS):
	""" Amazon MWS Reports API """

	ACCOUNT_TYPE = "Merchant"

	## REPORTS ###

	def get_report(self, report_id):
		data = dict(Action='GetReport', ReportId=report_id)
		return self.make_request(data)

	def get_report_count(self, report_types=(), acknowledged=None, fromdate=None, todate=None):
		data = dict(Action='GetReportCount',
					Acknowledged=acknowledged,
					AvailableFromDate=fromdate,
					AvailableToDate=todate)
		data.update(self.enumerate_param('ReportTypeList.Type.', report_types))
		return self.make_request(data)

	def get_report_list(self, requestids=(), max_count=None, types=(), acknowledged=None,
						fromdate=None, todate=None):
		data = dict(Action='GetReportList',
					Acknowledged=acknowledged,
					AvailableFromDate=fromdate,
					AvailableToDate=todate,
					MaxCount=max_count)
		data.update(self.enumerate_param('ReportRequestIdList.Id.', requestids))
		data.update(self.enumerate_param('ReportTypeList.Type.', types))
		return self.make_request(data)

	def get_report_list_by_next_token(self, token):
		data = dict(Action='GetReportListByNextToken', NextToken=token)
		return self.make_request(data)

	def get_report_request_count(self, report_types=(), processingstatuses=(), fromdate=None, todate=None):
		data = dict(Action='GetReportRequestCount',
					RequestedFromDate=fromdate,
					RequestedToDate=todate)
		data.update(self.enumerate_param('ReportTypeList.Type.', report_types))
		data.update(self.enumerate_param('ReportProcessingStatusList.Status.', processingstatuses))
		return self.make_request(data)

	def get_report_request_list(self, requestids=(), types=(), processingstatuses=(),
								max_count=None, fromdate=None, todate=None):
		data = dict(Action='GetReportRequestList',
					MaxCount=max_count,
					RequestedFromDate=fromdate,
					RequestedToDate=todate)
		data.update(self.enumerate_param('ReportRequestIdList.Id.', requestids))
		data.update(self.enumerate_param('ReportTypeList.Type.', types))
		data.update(self.enumerate_param('ReportProcessingStatusList.Status.', processingstatuses))
		return self.make_request(data)

	def get_report_request_list_by_next_token(self, token):
		data = dict(Action='GetReportRequestListByNextToken', NextToken=token)
		return self.make_request(data)

	def request_report(self, report_type, start_date=None, end_date=None, marketplaceids=()):
		data = dict(Action='RequestReport',
					ReportType=report_type,
					StartDate=start_date,
					EndDate=end_date)
		data.update(self.enumerate_param('MarketplaceIdList.Id.', marketplaceids))
		return self.make_request(data)

	### ReportSchedule ###

	def get_report_schedule_list(self, types=()):
		data = dict(Action='GetReportScheduleList')
		data.update(self.enumerate_param('ReportTypeList.Type.', types))
		return self.make_request(data)

	def get_report_schedule_count(self, types=()):
		data = dict(Action='GetReportScheduleCount')
		data.update(self.enumerate_param('ReportTypeList.Type.', types))
		return self.make_request(data)


class Orders(MWS):
	""" Amazon Orders API """

	URI = "/Orders/2013-09-01"
	VERSION = "2013-09-01"
	NS = '{https://mws.amazonservices.com/Orders/2011-01-01}'

	def list_orders(self, marketplaceids, created_after=None, created_before=None, lastupdatedafter=None,
					lastupdatedbefore=None, orderstatus=(), fulfillment_channels=(),
					payment_methods=(), buyer_email=None, seller_orderid=None, max_results='100'):

		data = dict(Action='ListOrders',
					CreatedAfter=created_after,
					CreatedBefore=created_before,
					LastUpdatedAfter=lastupdatedafter,
					LastUpdatedBefore=lastupdatedbefore,
					BuyerEmail=buyer_email,
					SellerOrderId=seller_orderid,
					MaxResultsPerPage=max_results,
					)
		data.update(self.enumerate_param('OrderStatus.Status.', orderstatus))
		data.update(self.enumerate_param('MarketplaceId.Id.', marketplaceids))
		data.update(self.enumerate_param('FulfillmentChannel.Channel.', fulfillment_channels))
		data.update(self.enumerate_param('PaymentMethod.Method.', payment_methods))
		return self.make_request(data)

	def list_orders_by_next_token(self, token):
		data = dict(Action='ListOrdersByNextToken', NextToken=token)
		return self.make_request(data)

	def get_order(self, amazon_order_ids):
		data = dict(Action='GetOrder')
		data.update(self.enumerate_param('AmazonOrderId.Id.', amazon_order_ids))
		return self.make_request(data)

	def list_order_items(self, amazon_order_id):
		data = dict(Action='ListOrderItems', AmazonOrderId=amazon_order_id)
		return self.make_request(data)

	def list_order_items_by_next_token(self, token):
		data = dict(Action='ListOrderItemsByNextToken', NextToken=token)
		return self.make_request(data)


class Products(MWS):
	""" Amazon MWS Products API """

	URI = '/Products/2011-10-01'
	VERSION = '2011-10-01'
	NS = '{http://mws.amazonservices.com/schema/Products/2011-10-01}'

	def list_matching_products(self, marketplaceid, query, contextid=None):
		""" Returns a list of products and their attributes, ordered by
			relevancy, based on a search query that you specify.
			Your search query can be a phrase that describes the product
			or it can be a product identifier such as a UPC, EAN, ISBN, or JAN.
		"""
		data = dict(Action='ListMatchingProducts',
					MarketplaceId=marketplaceid,
					Query=query,
					QueryContextId=contextid)
		return self.make_request(data)

	def get_matching_product(self, marketplaceid, asins):
		""" Returns a list of products and their attributes, based on a list of
			ASIN values that you specify.
		"""
		data = dict(Action='GetMatchingProduct', MarketplaceId=marketplaceid)
		data.update(self.enumerate_param('ASINList.ASIN.', asins))
		return self.make_request(data)

	def get_matching_product_for_id(self, marketplaceid, type, id):
		""" Returns a list of products and their attributes, based on a list of
			product identifier values (asin, sellersku, upc, ean, isbn and JAN)
			Added in Fourth Release, API version 2011-10-01
		"""
		data = dict(Action='GetMatchingProductForId',
					MarketplaceId=marketplaceid,
					IdType=type)
		data.update(self.enumerate_param('IdList.Id', id))
		return self.make_request(data)

	def get_competitive_pricing_for_sku(self, marketplaceid, skus):
		""" Returns the current competitive pricing of a product,
			based on the SellerSKU and MarketplaceId that you specify.
		"""
		data = dict(Action='GetCompetitivePricingForSKU', MarketplaceId=marketplaceid)
		data.update(self.enumerate_param('SellerSKUList.SellerSKU.', skus))
		return self.make_request(data)

	def get_competitive_pricing_for_asin(self, marketplaceid, asins):
		""" Returns the current competitive pricing of a product,
			based on the ASIN and MarketplaceId that you specify.
		"""
		data = dict(Action='GetCompetitivePricingForASIN', MarketplaceId=marketplaceid)
		data.update(self.enumerate_param('ASINList.ASIN.', asins))
		return self.make_request(data)

	def get_lowest_offer_listings_for_sku(self, marketplaceid, skus, condition="Any", excludeme="False"):
		data = dict(Action='GetLowestOfferListingsForSKU',
					MarketplaceId=marketplaceid,
					ItemCondition=condition,
					ExcludeMe=excludeme)
		data.update(self.enumerate_param('SellerSKUList.SellerSKU.', skus))
		return self.make_request(data)

	def get_lowest_offer_listings_for_asin(self, marketplaceid, asins, condition="Any", excludeme="False"):
		data = dict(Action='GetLowestOfferListingsForASIN',
					MarketplaceId=marketplaceid,
					ItemCondition=condition,
					ExcludeMe=excludeme)
		data.update(self.enumerate_param('ASINList.ASIN.', asins))
		return self.make_request(data)

	def get_product_categories_for_sku(self, marketplaceid, sku):
		data = dict(Action='GetProductCategoriesForSKU',
					MarketplaceId=marketplaceid,
					SellerSKU=sku)
		return self.make_request(data)

	def get_product_categories_for_asin(self, marketplaceid, asin):
		data = dict(Action='GetProductCategoriesForASIN',
					MarketplaceId=marketplaceid,
					ASIN=asin)
		return self.make_request(data)

	def get_my_price_for_sku(self, marketplaceid, skus, condition=None):
		data = dict(Action='GetMyPriceForSKU',
					MarketplaceId=marketplaceid,
					ItemCondition=condition)
		data.update(self.enumerate_param('SellerSKUList.SellerSKU.', skus))
		return self.make_request(data)

	def get_my_price_for_asin(self, marketplaceid, asins, condition=None):
		data = dict(Action='GetMyPriceForASIN',
					MarketplaceId=marketplaceid,
					ItemCondition=condition)
		data.update(self.enumerate_param('ASINList.ASIN.', asins))
		return self.make_request(data)


class Sellers(MWS):
	""" Amazon MWS Sellers API """

	URI = '/Sellers/2011-07-01'
	VERSION = '2011-07-01'
	NS = '{http://mws.amazonservices.com/schema/Sellers/2011-07-01}'

	def list_marketplace_participations(self):
		"""
			Returns a list of marketplaces a seller can participate in and
			a list of participations that include seller-specific information in that marketplace.
			The operation returns only those marketplaces where the seller's account is in an active state.
		"""

		data = dict(Action='ListMarketplaceParticipations')
		return self.make_request(data)

	def list_marketplace_participations_by_next_token(self, token):
		"""
			Takes a "NextToken" and returns the same information as "list_marketplace_participations".
			Based on the "NextToken".
		"""
		data = dict(Action='ListMarketplaceParticipations', NextToken=token)
		return self.make_request(data)

#### Fulfillment APIs ####

class InboundShipments(MWS):
	URI = "/FulfillmentInboundShipment/2010-10-01"
	VERSION = '2010-10-01'

	# To be completed


class Inventory(MWS):
	""" Amazon MWS Inventory Fulfillment API """

	URI = '/FulfillmentInventory/2010-10-01'
	VERSION = '2010-10-01'
	NS = "{http://mws.amazonaws.com/FulfillmentInventory/2010-10-01}"

	def list_inventory_supply(self, skus=(), datetime=None, response_group='Basic'):
		""" Returns information on available inventory """

		data = dict(Action='ListInventorySupply',
					QueryStartDateTime=datetime,
					ResponseGroup=response_group,
					)
		data.update(self.enumerate_param('SellerSkus.member.', skus))
		return self.make_request(data, "POST")

	def list_inventory_supply_by_next_token(self, token):
		data = dict(Action='ListInventorySupplyByNextToken', NextToken=token)
		return self.make_request(data, "POST")


class OutboundShipments(MWS):
	URI = "/FulfillmentOutboundShipment/2010-10-01"
	VERSION = "2010-10-01"
	# To be completed


class Recommendations(MWS):

	""" Amazon MWS Recommendations API """

	URI = '/Recommendations/2013-04-01'
	VERSION = '2013-04-01'
	NS = "{https://mws.amazonservices.com/Recommendations/2013-04-01}"

	def get_last_updated_time_for_recommendations(self, marketplaceid):
		"""
		Checks whether there are active recommendations for each category for the given marketplace, and if there are,
		returns the time when recommendations were last updated for each category.
		"""

		data = dict(Action='GetLastUpdatedTimeForRecommendations',
					MarketplaceId=marketplaceid)
		return self.make_request(data, "POST")

	def list_recommendations(self, marketplaceid, recommendationcategory=None):
		"""
		Returns your active recommendations for a specific category or for all categories for a specific marketplace.
		"""

		data = dict(Action="ListRecommendations",
					MarketplaceId=marketplaceid,
					RecommendationCategory=recommendationcategory)
		return self.make_request(data, "POST")

	def list_recommendations_by_next_token(self, token):
		"""
		Returns the next page of recommendations using the NextToken parameter.
		"""

		data = dict(Action="ListRecommendationsByNextToken",
					NextToken=token)
		return self.make_request(data, "POST")

class Finances(MWS):
	""" Amazon Finances API"""
	URI = '/Finances/2015-05-01'
	VERSION = '2015-05-01'
	NS = "{https://mws.amazonservices.com/Finances/2015-05-01}"

	def list_financial_events(self , posted_after=None, posted_before=None,
		 					amazon_order_id=None, max_results='100'):

		data = dict(Action='ListFinancialEvents',
					PostedAfter=posted_after,
					PostedBefore=posted_before,
					AmazonOrderId=amazon_order_id,
					MaxResultsPerPage=max_results,
					)
		return self.make_request(data)
