# -*- coding: utf-8 -*-
# Copyright (c) 2020, Frappe Technologies Pvt. Ltd. and contributors
# For license information, please see license.txt

import base64
import io
import json
import os
import re
import sys
import traceback

import frappe
import jwt
import requests
from frappe import _, bold
from frappe.core.page.background_jobs.background_jobs import get_info
from frappe.integrations.utils import make_get_request, make_post_request
from frappe.utils.background_jobs import enqueue
from frappe.utils.data import (
	add_to_date,
	cint,
	cstr,
	flt,
	format_date,
	get_link_to_form,
	getdate,
	now_datetime,
	time_diff_in_hours,
	time_diff_in_seconds,
)
from frappe.utils.scheduler import is_scheduler_inactive
from pyqrcode import create as qrcreate

from erpnext.regional.india.utils import get_gst_accounts, get_place_of_supply


@frappe.whitelist()
def validate_eligibility(doc):
	if isinstance(doc, str):
		doc = json.loads(doc)

	invalid_doctype = doc.get("doctype") != "Sales Invoice"
	if invalid_doctype:
		return False

	einvoicing_enabled = cint(frappe.db.get_single_value("E Invoice Settings", "enable"))
	if not einvoicing_enabled:
		return False

	einvoicing_eligible_from = (
		frappe.db.get_single_value("E Invoice Settings", "applicable_from") or "2021-04-01"
	)
	if getdate(doc.get("posting_date")) < getdate(einvoicing_eligible_from):
		return False

	invalid_company = not frappe.db.get_value("E Invoice User", {"company": doc.get("company")})
	invalid_supply_type = doc.get("gst_category") not in [
		"Registered Regular",
		"Registered Composition",
		"SEZ",
		"Overseas",
		"Deemed Export",
	]
	company_transaction = doc.get("billing_address_gstin") == doc.get("company_gstin")

	# if export invoice, then taxes can be empty
	# invoice can only be ineligible if no taxes applied and is not an export invoice
	no_taxes_applied = not doc.get("taxes") and not doc.get("gst_category") == "Overseas"
	has_non_gst_item = any(d for d in doc.get("items", []) if d.get("is_non_gst"))

	if (
		invalid_company
		or invalid_supply_type
		or company_transaction
		or no_taxes_applied
		or has_non_gst_item
	):
		return False

	return True


def validate_einvoice_fields(doc):
	invoice_eligible = validate_eligibility(doc)

	if not invoice_eligible:
		return

	if doc.docstatus == 0 and doc._action == "save":
		if doc.irn:
			frappe.throw(_("You cannot edit the invoice after generating IRN"), title=_("Edit Not Allowed"))
		if len(doc.name) > 16:
			raise_document_name_too_long_error()

		doc.einvoice_status = "Pending"

	elif doc.docstatus == 1 and doc._action == "submit" and not doc.irn:
		frappe.throw(_("You must generate IRN before submitting the document."), title=_("Missing IRN"))

	elif doc.irn and doc.docstatus == 2 and doc._action == "cancel" and not doc.irn_cancelled:
		frappe.throw(
			_("You must cancel IRN before cancelling the document."), title=_("Cancel Not Allowed")
		)


def raise_document_name_too_long_error():
	title = _("Document ID Too Long")
	msg = _("As you have E-Invoicing enabled, to be able to generate IRN for this invoice")
	msg += ", "
	msg += _("document id {} exceed 16 letters.").format(bold(_("should not")))
	msg += "<br><br>"
	msg += _("You must {} your {} in order to have document id of {} length 16.").format(
		bold(_("modify")), bold(_("naming series")), bold(_("maximum"))
	)
	msg += _("Please account for ammended documents too.")
	frappe.throw(msg, title=title)


def read_json(name):
	file_path = os.path.join(os.path.dirname(__file__), "{name}.json".format(name=name))
	with open(file_path, "r") as f:
		return cstr(f.read())


def get_transaction_details(invoice):
	supply_type = ""
	if (
		invoice.gst_category == "Registered Regular" or invoice.gst_category == "Registered Composition"
	):
		supply_type = "B2B"
	elif invoice.gst_category == "SEZ":
		if invoice.export_type == "Without Payment of Tax":
			supply_type = "SEZWOP"
		else:
			supply_type = "SEZWP"
	elif invoice.gst_category == "Overseas":
		if invoice.export_type == "Without Payment of Tax":
			supply_type = "EXPWOP"
		else:
			supply_type = "EXPWP"
	elif invoice.gst_category == "Deemed Export":
		supply_type = "DEXP"

	if not supply_type:
		rr, rc, sez, overseas, export = (
			bold("Registered Regular"),
			bold("Registered Composition"),
			bold("SEZ"),
			bold("Overseas"),
			bold("Deemed Export"),
		)
		frappe.throw(
			_("GST category should be one of {}, {}, {}, {}, {}").format(rr, rc, sez, overseas, export),
			title=_("Invalid Supply Type"),
		)

	return frappe._dict(
		dict(tax_scheme="GST", supply_type=supply_type, reverse_charge=invoice.reverse_charge)
	)


def get_doc_details(invoice):
	if getdate(invoice.posting_date) < getdate("2021-01-01"):
		frappe.throw(
			_("IRN generation is not allowed for invoices dated before 1st Jan 2021"),
			title=_("Not Allowed"),
		)

	if invoice.is_return:
		invoice_type = "CRN"
	elif invoice.is_debit_note:
		invoice_type = "DBN"
	else:
		invoice_type = "INV"

	invoice_name = invoice.name
	invoice_date = format_date(invoice.posting_date, "dd/mm/yyyy")

	return frappe._dict(
		dict(invoice_type=invoice_type, invoice_name=invoice_name, invoice_date=invoice_date)
	)


def validate_address_fields(address, skip_gstin_validation):
	if (
		(not address.gstin and not skip_gstin_validation)
		or not address.city
		or not address.pincode
		or not address.address_title
		or not address.address_line1
		or not address.gst_state_number
	):

		frappe.throw(
			msg=_(
				"Address Lines, City, Pincode, GSTIN are mandatory for address {}. Please set them and try again."
			).format(address.name),
			title=_("Missing Address Fields"),
		)

	if address.address_line2 and len(address.address_line2) < 2:
		# to prevent "The field Address 2 must be a string with a minimum length of 3 and a maximum length of 100"
		address.address_line2 = ""


def get_party_details(address_name, skip_gstin_validation=False):
	addr = frappe.get_doc("Address", address_name)

	validate_address_fields(addr, skip_gstin_validation)

	if addr.gst_state_number == 97:
		# according to einvoice standard
		addr.pincode = 999999

	party_address_details = frappe._dict(
		dict(
			legal_name=sanitize_for_json(addr.address_title),
			location=sanitize_for_json(addr.city),
			pincode=addr.pincode,
			gstin=addr.gstin,
			state_code=addr.gst_state_number,
			address_line1=sanitize_for_json(addr.address_line1),
			address_line2=sanitize_for_json(addr.address_line2),
		)
	)

	return party_address_details


def get_overseas_address_details(address_name):
	address_title, address_line1, address_line2, city = frappe.db.get_value(
		"Address", address_name, ["address_title", "address_line1", "address_line2", "city"]
	)

	if not address_title or not address_line1 or not city:
		frappe.throw(
			msg=_(
				"Address lines and city is mandatory for address {}. Please set them and try again."
			).format(get_link_to_form("Address", address_name)),
			title=_("Missing Address Fields"),
		)

	return frappe._dict(
		dict(
			gstin="URP",
			legal_name=sanitize_for_json(address_title),
			location=city,
			address_line1=sanitize_for_json(address_line1),
			address_line2=sanitize_for_json(address_line2),
			pincode=999999,
			state_code=96,
			place_of_supply=96,
		)
	)


def get_item_list(invoice):
	item_list = []

	for d in invoice.items:
		einvoice_item_schema = read_json("einv_item_template")
		item = frappe._dict({})
		item.update(d.as_dict())

		item.sr_no = d.idx
		item.description = sanitize_for_json(d.item_name)

		item.qty = abs(item.qty)
		if flt(item.qty) != 0.0:
			item.unit_rate = abs(item.taxable_value / item.qty)
		else:
			item.unit_rate = abs(item.taxable_value)
		item.gross_amount = abs(item.taxable_value)
		item.taxable_value = abs(item.taxable_value)
		item.discount_amount = 0

		item.is_service_item = "Y" if item.gst_hsn_code and item.gst_hsn_code[:2] == "99" else "N"
		item.serial_no = ""

		item = update_item_taxes(invoice, item)

		item.total_value = abs(
			item.taxable_value
			+ item.igst_amount
			+ item.sgst_amount
			+ item.cgst_amount
			+ item.cess_amount
			+ item.cess_nadv_amount
			+ item.other_charges
		)
		einv_item = einvoice_item_schema.format(item=item)
		item_list.append(einv_item)

	return ", ".join(item_list)


def update_item_taxes(invoice, item):
	gst_accounts = get_gst_accounts(invoice.company)
	gst_accounts_list = [d for accounts in gst_accounts.values() for d in accounts if d]

	for attr in [
		"tax_rate",
		"cess_rate",
		"cess_nadv_amount",
		"cgst_amount",
		"sgst_amount",
		"igst_amount",
		"cess_amount",
		"cess_nadv_amount",
		"other_charges",
	]:
		item[attr] = 0

	for t in invoice.taxes:
		is_applicable = t.tax_amount and t.account_head in gst_accounts_list
		if is_applicable:
			# this contains item wise tax rate & tax amount (incl. discount)
			item_tax_detail = json.loads(t.item_wise_tax_detail).get(item.item_code or item.item_name)

			item_tax_rate = item_tax_detail[0]
			# item tax amount excluding discount amount
			item_tax_amount = (item_tax_rate / 100) * item.taxable_value

			if t.account_head in gst_accounts.cess_account:
				item_tax_amount_after_discount = item_tax_detail[1]
				if t.charge_type == "On Item Quantity":
					item.cess_nadv_amount += abs(item_tax_amount_after_discount)
				else:
					item.cess_rate += item_tax_rate
					item.cess_amount += abs(item_tax_amount_after_discount)

			for tax_type in ["igst", "cgst", "sgst", "utgst"]:
				if t.account_head in gst_accounts[f"{tax_type}_account"]:
					item.tax_rate += item_tax_rate
					if tax_type == "utgst":
						# utgst taxes are reported same as sgst tax
						item["sgst_amount"] += abs(item_tax_amount)
					else:
						item[f"{tax_type}_amount"] += abs(item_tax_amount)
		else:
			# TODO: other charges per item
			pass

	return item


def get_invoice_value_details(invoice):
	invoice_value_details = frappe._dict(dict())
	invoice_value_details.base_total = abs(sum([i.taxable_value for i in invoice.get("items")]))
	invoice_value_details.invoice_discount_amt = 0

	invoice_value_details.round_off = invoice.base_rounding_adjustment
	invoice_value_details.base_grand_total = abs(invoice.base_rounded_total) or abs(
		invoice.base_grand_total
	)
	invoice_value_details.grand_total = abs(invoice.rounded_total) or abs(invoice.grand_total)

	invoice_value_details = update_invoice_taxes(invoice, invoice_value_details)

	return invoice_value_details


def update_invoice_taxes(invoice, invoice_value_details):
	gst_accounts = get_gst_accounts(invoice.company)
	gst_accounts_list = [d for accounts in gst_accounts.values() for d in accounts if d]

	invoice_value_details.total_cgst_amt = 0
	invoice_value_details.total_sgst_amt = 0
	invoice_value_details.total_igst_amt = 0
	invoice_value_details.total_cess_amt = 0
	invoice_value_details.total_other_charges = 0
	considered_rows = []

	for t in invoice.taxes:
		tax_amount = t.base_tax_amount_after_discount_amount
		if t.account_head in gst_accounts_list:
			if t.account_head in gst_accounts.cess_account:
				# using after discount amt since item also uses after discount amt for cess calc
				invoice_value_details.total_cess_amt += abs(t.base_tax_amount_after_discount_amount)

			for tax_type in ["igst", "cgst", "sgst", "utgst"]:
				if t.account_head in gst_accounts[f"{tax_type}_account"]:
					if tax_type == "utgst":
						invoice_value_details["total_sgst_amt"] += abs(tax_amount)
					else:
						invoice_value_details[f"total_{tax_type}_amt"] += abs(tax_amount)

				update_other_charges(t, invoice_value_details, gst_accounts_list, invoice, considered_rows)

		else:
			invoice_value_details.total_other_charges += abs(tax_amount)

	return invoice_value_details


def update_other_charges(
	tax_row, invoice_value_details, gst_accounts_list, invoice, considered_rows
):
	prev_row_id = cint(tax_row.row_id) - 1
	if tax_row.account_head in gst_accounts_list and prev_row_id not in considered_rows:
		if tax_row.charge_type == "On Previous Row Amount":
			amount = invoice.get("taxes")[prev_row_id].tax_amount_after_discount_amount
			invoice_value_details.total_other_charges -= abs(amount)
			considered_rows.append(prev_row_id)
		if tax_row.charge_type == "On Previous Row Total":
			amount = invoice.get("taxes")[prev_row_id].base_total - invoice.base_net_total
			invoice_value_details.total_other_charges -= abs(amount)
			considered_rows.append(prev_row_id)


def get_payment_details(invoice):
	payee_name = invoice.company
	mode_of_payment = ""
	paid_amount = invoice.base_paid_amount
	outstanding_amount = invoice.outstanding_amount

	return frappe._dict(
		dict(
			payee_name=payee_name,
			mode_of_payment=mode_of_payment,
			paid_amount=paid_amount,
			outstanding_amount=outstanding_amount,
		)
	)


def get_return_doc_reference(invoice):
	invoice_date = frappe.db.get_value("Sales Invoice", invoice.return_against, "posting_date")
	return frappe._dict(
		dict(invoice_name=invoice.return_against, invoice_date=format_date(invoice_date, "dd/mm/yyyy"))
	)


def get_eway_bill_details(invoice):
	if invoice.is_return:
		frappe.throw(
			_(
				"E-Way Bill cannot be generated for Credit Notes & Debit Notes. Please clear fields in the Transporter Section of the invoice."
			),
			title=_("Invalid Fields"),
		)

	mode_of_transport = {"": "", "Road": "1", "Air": "2", "Rail": "3", "Ship": "4"}
	vehicle_type = {"Regular": "R", "Over Dimensional Cargo (ODC)": "O"}

	return frappe._dict(
		dict(
			gstin=invoice.gst_transporter_id,
			name=invoice.transporter_name,
			mode_of_transport=mode_of_transport[invoice.mode_of_transport or ""] or None,
			distance=invoice.distance or 0,
			document_name=invoice.lr_no,
			document_date=format_date(invoice.lr_date, "dd/mm/yyyy"),
			vehicle_no=invoice.vehicle_no,
			vehicle_type=vehicle_type[invoice.gst_vehicle_type],
		)
	)


def validate_mandatory_fields(invoice):
	if not invoice.company_address:
		frappe.throw(
			_(
				"Company Address is mandatory to fetch company GSTIN details. Please set Company Address and try again."
			),
			title=_("Missing Fields"),
		)
	if not invoice.customer_address:
		frappe.throw(
			_(
				"Customer Address is mandatory to fetch customer GSTIN details. Please set Company Address and try again."
			),
			title=_("Missing Fields"),
		)
	if not frappe.db.get_value("Address", invoice.company_address, "gstin"):
		frappe.throw(
			_(
				"GSTIN is mandatory to fetch company GSTIN details. Please enter GSTIN in selected company address."
			),
			title=_("Missing Fields"),
		)
	if invoice.gst_category != "Overseas" and not frappe.db.get_value(
		"Address", invoice.customer_address, "gstin"
	):
		frappe.throw(
			_(
				"GSTIN is mandatory to fetch customer GSTIN details. Please enter GSTIN in selected customer address."
			),
			title=_("Missing Fields"),
		)


def validate_totals(einvoice):
	item_list = einvoice["ItemList"]
	value_details = einvoice["ValDtls"]

	total_item_ass_value = 0
	total_item_cgst_value = 0
	total_item_sgst_value = 0
	total_item_igst_value = 0
	total_item_value = 0
	for item in item_list:
		total_item_ass_value += flt(item["AssAmt"])
		total_item_cgst_value += flt(item["CgstAmt"])
		total_item_sgst_value += flt(item["SgstAmt"])
		total_item_igst_value += flt(item["IgstAmt"])
		total_item_value += flt(item["TotItemVal"])

		if (
			abs(flt(item["AssAmt"]) * flt(item["GstRt"]) / 100)
			- (flt(item["CgstAmt"]) + flt(item["SgstAmt"]) + flt(item["IgstAmt"]))
			> 1
		):
			frappe.throw(
				_(
					"Row #{}: GST rate is invalid. Please remove tax rows with zero tax amount from taxes table."
				).format(item.idx)
			)

	if abs(flt(value_details["AssVal"]) - total_item_ass_value) > 1:
		frappe.throw(
			_(
				"Total Taxable Value of the items is not equal to the Invoice Net Total. Please check item taxes / discounts for any correction."
			)
		)

	if (
		abs(
			flt(value_details["CgstVal"])
			+ flt(value_details["SgstVal"])
			- total_item_cgst_value
			- total_item_sgst_value
		)
		> 1
	):
		frappe.throw(
			_(
				"CGST + SGST value of the items is not equal to total CGST + SGST value. Please review taxes for any correction."
			)
		)

	if abs(flt(value_details["IgstVal"]) - total_item_igst_value) > 1:
		frappe.throw(
			_(
				"IGST value of all items is not equal to total IGST value. Please review taxes for any correction."
			)
		)

	if (
		abs(
			flt(value_details["TotInvVal"])
			+ flt(value_details["Discount"])
			- flt(value_details["OthChrg"])
			- flt(value_details["RndOffAmt"])
			- total_item_value
		)
		> 1
	):
		frappe.throw(
			_(
				"Total Value of the items is not equal to the Invoice Grand Total. Please check item taxes / discounts for any correction."
			)
		)

	calculated_invoice_value = (
		flt(value_details["AssVal"])
		+ flt(value_details["CgstVal"])
		+ flt(value_details["SgstVal"])
		+ flt(value_details["IgstVal"])
		+ flt(value_details["CesVal"])
		+ flt(value_details["OthChrg"])
		+ flt(value_details["RndOffAmt"])
		- flt(value_details["Discount"])
	)

	if abs(flt(value_details["TotInvVal"]) - calculated_invoice_value) > 1:
		frappe.throw(
			_(
				"Total Item Value + Taxes - Discount is not equal to the Invoice Grand Total. Please check taxes / discounts for any correction."
			)
		)


def make_einvoice(invoice):
	validate_mandatory_fields(invoice)

	schema = read_json("einv_template")

	transaction_details = get_transaction_details(invoice)
	item_list = get_item_list(invoice)
	doc_details = get_doc_details(invoice)
	invoice_value_details = get_invoice_value_details(invoice)
	seller_details = get_party_details(invoice.company_address)

	if invoice.gst_category == "Overseas":
		buyer_details = get_overseas_address_details(invoice.customer_address)
	else:
		buyer_details = get_party_details(invoice.customer_address)
		place_of_supply = get_place_of_supply(invoice, invoice.doctype)
		if place_of_supply:
			place_of_supply = place_of_supply.split("-")[0]
		else:
			place_of_supply = sanitize_for_json(invoice.billing_address_gstin)[:2]
		buyer_details.update(dict(place_of_supply=place_of_supply))

	seller_details.update(dict(legal_name=invoice.company))
	buyer_details.update(dict(legal_name=invoice.customer_name or invoice.customer))

	shipping_details = payment_details = prev_doc_details = eway_bill_details = frappe._dict({})
	if invoice.shipping_address_name and invoice.customer_address != invoice.shipping_address_name:
		if invoice.gst_category == "Overseas":
			shipping_details = get_overseas_address_details(invoice.shipping_address_name)
		else:
			shipping_details = get_party_details(invoice.shipping_address_name, skip_gstin_validation=True)

	dispatch_details = frappe._dict({})
	if invoice.dispatch_address_name:
		dispatch_details = get_party_details(invoice.dispatch_address_name, skip_gstin_validation=True)

	if invoice.is_pos and invoice.base_paid_amount:
		payment_details = get_payment_details(invoice)

	if invoice.is_return and invoice.return_against:
		prev_doc_details = get_return_doc_reference(invoice)

	if invoice.transporter and not invoice.is_return:
		eway_bill_details = get_eway_bill_details(invoice)

	# not yet implemented
	period_details = export_details = frappe._dict({})

	einvoice = schema.format(
		transaction_details=transaction_details,
		doc_details=doc_details,
		dispatch_details=dispatch_details,
		seller_details=seller_details,
		buyer_details=buyer_details,
		shipping_details=shipping_details,
		item_list=item_list,
		invoice_value_details=invoice_value_details,
		payment_details=payment_details,
		period_details=period_details,
		prev_doc_details=prev_doc_details,
		export_details=export_details,
		eway_bill_details=eway_bill_details,
	)

	try:
		einvoice = safe_json_load(einvoice)
		einvoice = santize_einvoice_fields(einvoice)
	except json.JSONDecodeError:
		raise
	except Exception:
		show_link_to_error_log(invoice, einvoice)

	try:
		validate_totals(einvoice)
	except Exception:
		log_error(einvoice)
		raise

	return einvoice


def show_link_to_error_log(invoice, einvoice):
	err_log = log_error(einvoice)
	link_to_error_log = get_link_to_form("Error Log", err_log.name, "Error Log")
	frappe.throw(
		_(
			"An error occurred while creating e-invoice for {}. Please check {} for more information."
		).format(invoice.name, link_to_error_log),
		title=_("E Invoice Creation Failed"),
	)


def log_error(data=None):
	if isinstance(data, str):
		data = json.loads(data)

	seperator = "--" * 50
	err_tb = traceback.format_exc()
	err_msg = str(sys.exc_info()[1])
	data = json.dumps(data, indent=4)

	message = "\n".join(["Error", err_msg, seperator, "Data:", data, seperator, "Exception:", err_tb])
	return frappe.log_error(title=_("E Invoice Request Failed"), message=message)


def santize_einvoice_fields(einvoice):
	int_fields = ["Pin", "Distance", "CrDay"]
	float_fields = [
		"Qty",
		"FreeQty",
		"UnitPrice",
		"TotAmt",
		"Discount",
		"PreTaxVal",
		"AssAmt",
		"GstRt",
		"IgstAmt",
		"CgstAmt",
		"SgstAmt",
		"CesRt",
		"CesAmt",
		"CesNonAdvlAmt",
		"StateCesRt",
		"StateCesAmt",
		"StateCesNonAdvlAmt",
		"OthChrg",
		"TotItemVal",
		"AssVal",
		"CgstVal",
		"SgstVal",
		"IgstVal",
		"CesVal",
		"StCesVal",
		"Discount",
		"OthChrg",
		"RndOffAmt",
		"TotInvVal",
		"TotInvValFc",
		"PaidAmt",
		"PaymtDue",
		"ExpDuty",
	]
	copy = einvoice.copy()
	for key, value in copy.items():
		if isinstance(value, list):
			for idx, d in enumerate(value):
				santized_dict = santize_einvoice_fields(d)
				if santized_dict:
					einvoice[key][idx] = santized_dict
				else:
					einvoice[key].pop(idx)

			if not einvoice[key]:
				einvoice.pop(key, None)

		elif isinstance(value, dict):
			santized_dict = santize_einvoice_fields(value)
			if santized_dict:
				einvoice[key] = santized_dict
			else:
				einvoice.pop(key, None)

		elif not value or value == "None":
			einvoice.pop(key, None)

		elif key in float_fields:
			einvoice[key] = flt(value, 2)

		elif key in int_fields:
			einvoice[key] = cint(value)

	return einvoice


def safe_json_load(json_string):
	try:
		return json.loads(json_string)
	except json.JSONDecodeError as e:
		# print a snippet of 40 characters around the location where error occured
		pos = e.pos
		start, end = max(0, pos - 20), min(len(json_string) - 1, pos + 20)
		snippet = json_string[start:end]
		frappe.throw(
			_(
				"Error in input data. Please check for any special characters near following input: <br> {}"
			).format(snippet),
			title=_("Invalid JSON"),
			exc=e,
		)


class RequestFailed(Exception):
	pass


class CancellationNotAllowed(Exception):
	pass


class GSPConnector:
	def __init__(self, doctype=None, docname=None):
		self.doctype = doctype
		self.docname = docname

		self.set_invoice()
		self.set_credentials()

		# authenticate url is same for sandbox & live
		self.authenticate_url = "https://gsp.adaequare.com/gsp/authenticate?grant_type=token"
		self.base_url = (
			"https://gsp.adaequare.com"
			if not self.e_invoice_settings.sandbox_mode
			else "https://gsp.adaequare.com/test"
		)

		self.cancel_irn_url = self.base_url + "/enriched/ei/api/invoice/cancel"
		self.irn_details_url = self.base_url + "/enriched/ei/api/invoice/irn"
		self.generate_irn_url = self.base_url + "/enriched/ei/api/invoice"
		self.gstin_details_url = self.base_url + "/enriched/ei/api/master/gstin"
		# cancel_ewaybill_url will only work if user have bought ewb api from adaequare.
		self.cancel_ewaybill_url = self.base_url + "/enriched/ewb/ewayapi?action=CANEWB"
		self.generate_ewaybill_url = self.base_url + "/enriched/ei/api/ewaybill"
		self.get_qrcode_url = self.base_url + "/enriched/ei/others/qr/image"

	def set_invoice(self):
		self.invoice = None
		if self.doctype and self.docname:
			self.invoice = frappe.get_cached_doc(self.doctype, self.docname)

	def set_credentials(self):
		self.e_invoice_settings = frappe.get_cached_doc("E Invoice Settings")

		if not self.e_invoice_settings.enable:
			frappe.throw(
				_("E-Invoicing is disabled. Please enable it from {} to generate e-invoices.").format(
					get_link_to_form("E Invoice Settings", "E Invoice Settings")
				)
			)

		if self.invoice:
			gstin = self.get_seller_gstin()
			credentials_for_gstin = [d for d in self.e_invoice_settings.credentials if d.gstin == gstin]
			if credentials_for_gstin:
				self.credentials = credentials_for_gstin[0]
			else:
				frappe.throw(
					_(
						"Cannot find e-invoicing credentials for selected Company GSTIN. Please check E-Invoice Settings"
					)
				)
		else:
			self.credentials = (
				self.e_invoice_settings.credentials[0] if self.e_invoice_settings.credentials else None
			)

	def get_seller_gstin(self):
		gstin = frappe.db.get_value("Address", self.invoice.company_address, "gstin")
		if not gstin:
			frappe.throw(
				_("Cannot retrieve Company GSTIN. Please select company address with valid GSTIN.")
			)
		return gstin

	def get_auth_token(self):
		if time_diff_in_seconds(self.e_invoice_settings.token_expiry, now_datetime()) < 150.0:
			self.fetch_auth_token()

		return self.e_invoice_settings.auth_token

	def make_request(self, request_type, url, headers=None, data=None):
		try:
			if request_type == "post":
				res = make_post_request(url, headers=headers, data=data)
			else:
				res = make_get_request(url, headers=headers, data=data)

		except requests.exceptions.HTTPError as e:
			if e.response.status_code in [401, 403] and not hasattr(self, "token_auto_refreshed"):
				self.auto_refresh_token()
				headers = self.get_headers()
				return self.make_request(request_type, url, headers, data)

		self.log_request(url, headers, data, res)
		return res

	def auto_refresh_token(self):
		self.token_auto_refreshed = True
		self.fetch_auth_token()

	def log_request(self, url, headers, data, res):
		headers.update({"password": self.credentials.password})
		request_log = frappe.get_doc(
			{
				"doctype": "E Invoice Request Log",
				"user": frappe.session.user,
				"reference_invoice": self.invoice.name if self.invoice else None,
				"url": url,
				"headers": json.dumps(headers, indent=4) if headers else None,
				"data": json.dumps(data, indent=4) if isinstance(data, dict) else data,
				"response": json.dumps(res, indent=4) if res else None,
			}
		)
		request_log.save(ignore_permissions=True)
		frappe.db.commit()

	def get_client_credentials(self):
		if self.e_invoice_settings.client_id and self.e_invoice_settings.client_secret:
			return self.e_invoice_settings.client_id, self.e_invoice_settings.get_password("client_secret")

		return frappe.conf.einvoice_client_id, frappe.conf.einvoice_client_secret

	def fetch_auth_token(self):
		client_id, client_secret = self.get_client_credentials()
		headers = {"gspappid": client_id, "gspappsecret": client_secret}
		res = {}
		try:
			res = self.make_request("post", self.authenticate_url, headers)
			self.e_invoice_settings.auth_token = "{} {}".format(
				res.get("token_type"), res.get("access_token")
			)
			self.e_invoice_settings.token_expiry = add_to_date(None, seconds=res.get("expires_in"))
			self.e_invoice_settings.save(ignore_permissions=True)
			self.e_invoice_settings.reload()

		except Exception:
			log_error(res)
			self.raise_error(True)

	def get_headers(self):
		return {
			"content-type": "application/json",
			"user_name": self.credentials.username,
			"password": self.credentials.get_password(),
			"gstin": self.credentials.gstin,
			"authorization": self.get_auth_token(),
			"requestid": str(base64.b64encode(os.urandom(18))),
		}

	def fetch_gstin_details(self, gstin):
		headers = self.get_headers()

		try:
			params = "?gstin={gstin}".format(gstin=gstin)
			res = self.make_request("get", self.gstin_details_url + params, headers)
			if res.get("success"):
				return res.get("result")
			else:
				log_error(res)
				raise RequestFailed

		except RequestFailed:
			self.raise_error()

		except Exception:
			log_error()
			self.raise_error(True)

	@staticmethod
	def get_gstin_details(gstin):
		"""fetch and cache GSTIN details"""
		if not hasattr(frappe.local, "gstin_cache"):
			frappe.local.gstin_cache = {}

		key = gstin
		gsp_connector = GSPConnector()
		details = gsp_connector.fetch_gstin_details(gstin)

		frappe.local.gstin_cache[key] = details
		frappe.cache().hset("gstin_cache", key, details)
		return details

	def generate_irn(self):
		data = {}
		try:
			headers = self.get_headers()
			einvoice = make_einvoice(self.invoice)
			data = json.dumps(einvoice, indent=4)
			res = self.make_request("post", self.generate_irn_url, headers, data)

			if res.get("success"):
				self.set_einvoice_data(res.get("result"))

			elif "2150" in res.get("message"):
				# IRN already generated but not updated in invoice
				# Extract the IRN from the response description and fetch irn details
				irn = res.get("result")[0].get("Desc").get("Irn")
				irn_details = self.get_irn_details(irn)
				if irn_details:
					self.set_einvoice_data(irn_details)
				else:
					raise RequestFailed(
						"IRN has already been generated for the invoice but cannot fetch details for the it. \
						Contact ERPNext support to resolve the issue."
					)

			else:
				raise RequestFailed

		except RequestFailed:
			errors = self.sanitize_error_message(res.get("message"))
			self.set_failed_status(errors=errors)
			self.raise_error(errors=errors)

		except Exception as e:
			self.set_failed_status(errors=str(e))
			log_error(data)
			self.raise_error(True)

	@staticmethod
	def bulk_generate_irn(invoices):
		gsp_connector = GSPConnector()
		gsp_connector.doctype = "Sales Invoice"

		failed = []

		for invoice in invoices:
			try:
				gsp_connector.docname = invoice
				gsp_connector.set_invoice()
				gsp_connector.set_credentials()
				gsp_connector.generate_irn()

			except Exception as e:
				failed.append({"docname": invoice, "message": str(e)})

		return failed

	def fetch_and_attach_qrcode_from_irn(self):
		is_qrcode_file_attached = self.invoice.qrcode_image and frappe.db.exists(
			"File",
			{
				"attached_to_doctype": "Sales Invoice",
				"attached_to_name": self.invoice.name,
				"file_url": self.invoice.qrcode_image,
				"attached_to_field": "qrcode_image",
			},
		)
		if not is_qrcode_file_attached:
			if self.invoice.signed_qr_code:
				self.attach_qrcode_image()
				frappe.db.set_value(
					"Sales Invoice", self.invoice.name, "qrcode_image", self.invoice.qrcode_image
				)
				frappe.msgprint(_("QR Code attached to the invoice."), alert=True)
			else:
				qrcode = self.get_qrcode_from_irn(self.invoice.irn)
				if qrcode:
					qrcode_file = self.create_qr_code_file(qrcode)
					frappe.db.set_value("Sales Invoice", self.invoice.name, "qrcode_image", qrcode_file.file_url)
					frappe.msgprint(_("QR Code attached to the invoice."), alert=True)
				else:
					frappe.msgprint(_("QR Code not found for the IRN"), alert=True)
		else:
			frappe.msgprint(_("QR Code is already Attached"), indicator="green", alert=True)

	def get_qrcode_from_irn(self, irn):
		import requests

		headers = self.get_headers()
		headers.update({"width": "215", "height": "215", "imgtype": "jpg", "irn": irn})

		try:
			# using requests.get instead of make_request to avoid parsing the response
			res = requests.get(self.get_qrcode_url, headers=headers)
			self.log_request(self.get_qrcode_url, headers, None, None)
			if res.status_code == 200:
				return res.content
			else:
				raise RequestFailed(str(res.content, "utf-8"))

		except RequestFailed as e:
			self.raise_error(errors=str(e))

		except Exception:
			log_error()
			self.raise_error()

	def get_irn_details(self, irn):
		headers = self.get_headers()

		try:
			params = "?irn={irn}".format(irn=irn)
			res = self.make_request("get", self.irn_details_url + params, headers)
			if res.get("success"):
				return res.get("result")
			else:
				raise RequestFailed

		except RequestFailed:
			errors = self.sanitize_error_message(res.get("message"))
			self.raise_error(errors=errors)

		except Exception:
			log_error()
			self.raise_error(True)

	def cancel_irn(self, irn, reason, remark):
		data, res = {}, {}
		try:
			# validate cancellation
			if time_diff_in_hours(now_datetime(), self.invoice.ack_date) > 24:
				frappe.throw(
					_("E-Invoice cannot be cancelled after 24 hours of IRN generation."),
					title=_("Not Allowed"),
					exc=CancellationNotAllowed,
				)
			if not irn:
				frappe.throw(
					_("IRN not found. You must generate IRN before cancelling."),
					title=_("Not Allowed"),
					exc=CancellationNotAllowed,
				)

			headers = self.get_headers()
			data = json.dumps({"Irn": irn, "Cnlrsn": reason, "Cnlrem": remark}, indent=4)

			res = self.make_request("post", self.cancel_irn_url, headers, data)
			if res.get("success") or "9999" in res.get("message"):
				self.invoice.irn_cancelled = 1
				self.invoice.irn_cancel_date = res.get("result")["CancelDate"] if res.get("result") else ""
				self.invoice.einvoice_status = "Cancelled"
				self.invoice.flags.updater_reference = {
					"doctype": self.invoice.doctype,
					"docname": self.invoice.name,
					"label": _("IRN Cancelled - {}").format(remark),
				}
				self.update_invoice()

			else:
				raise RequestFailed

		except RequestFailed:
			errors = self.sanitize_error_message(res.get("message"))
			self.set_failed_status(errors=errors)
			self.raise_error(errors=errors)

		except CancellationNotAllowed as e:
			self.set_failed_status(errors=str(e))
			self.raise_error(errors=str(e))

		except Exception as e:
			self.set_failed_status(errors=str(e))
			log_error(data)
			self.raise_error(True)

	@staticmethod
	def bulk_cancel_irn(invoices, reason, remark):
		gsp_connector = GSPConnector()
		gsp_connector.doctype = "Sales Invoice"

		failed = []

		for invoice in invoices:
			try:
				gsp_connector.docname = invoice
				gsp_connector.set_invoice()
				gsp_connector.set_credentials()
				irn = gsp_connector.invoice.irn
				gsp_connector.cancel_irn(irn, reason, remark)

			except Exception as e:
				failed.append({"docname": invoice, "message": str(e)})

		return failed

	def generate_eway_bill(self, **kwargs):
		args = frappe._dict(kwargs)

		headers = self.get_headers()
		eway_bill_details = get_eway_bill_details(args)
		data = json.dumps(
			{
				"Irn": args.irn,
				"Distance": cint(eway_bill_details.distance),
				"TransMode": eway_bill_details.mode_of_transport,
				"TransId": eway_bill_details.gstin,
				"TransName": eway_bill_details.name,
				"TrnDocDt": eway_bill_details.document_date,
				"TrnDocNo": eway_bill_details.document_name,
				"VehNo": eway_bill_details.vehicle_no,
				"VehType": eway_bill_details.vehicle_type,
			},
			indent=4,
		)

		try:
			res = self.make_request("post", self.generate_ewaybill_url, headers, data)
			if res.get("success"):
				self.invoice.ewaybill = res.get("result").get("EwbNo")
				self.invoice.eway_bill_validity = res.get("result").get("EwbValidTill")
				self.invoice.eway_bill_cancelled = 0
				self.invoice.update(args)
				if res.get("info"):
					info = res.get("info")
					# when we have more features (responses) in eway bill, we can add them using below forloop.
					for msg in info:
						if msg.get("InfCd") == "EWBPPD":
							pin_to_pin_distance = int(re.search(r"\d+", msg.get("Desc")).group())
							frappe.msgprint(
								_("Auto Calculated Distance is {} KM.").format(str(pin_to_pin_distance)),
								title="Notification",
								indicator="green",
								alert=True,
							)
							self.invoice.distance = flt(pin_to_pin_distance)
				self.invoice.flags.updater_reference = {
					"doctype": self.invoice.doctype,
					"docname": self.invoice.name,
					"label": _("E-Way Bill Generated"),
				}
				self.update_invoice()

			else:
				raise RequestFailed

		except RequestFailed:
			errors = self.sanitize_error_message(res.get("message"))
			self.raise_error(errors=errors)

		except Exception:
			log_error(data)
			self.raise_error(True)

	def cancel_eway_bill(self, eway_bill, reason, remark):
		headers = self.get_headers()
		data = json.dumps({"ewbNo": eway_bill, "cancelRsnCode": reason, "cancelRmrk": remark}, indent=4)
		headers["username"] = headers["user_name"]
		del headers["user_name"]
		try:
			res = self.make_request("post", self.cancel_ewaybill_url, headers, data)
			if res.get("success"):
				self.invoice.ewaybill = ""
				self.invoice.eway_bill_cancelled = 1
				self.invoice.flags.updater_reference = {
					"doctype": self.invoice.doctype,
					"docname": self.invoice.name,
					"label": _("E-Way Bill Cancelled - {}").format(remark),
				}
				self.update_invoice()

			else:
				raise RequestFailed

		except RequestFailed:
			errors = self.sanitize_error_message(res.get("message"))
			self.raise_error(errors=errors)

		except Exception:
			log_error(data)
			self.raise_error(True)

	def sanitize_error_message(self, message):
		"""
		On validation errors, response message looks something like this:
		message = '2174 : For inter-state transaction, CGST and SGST amounts are not applicable; only IGST amount is applicable,
		                        3095 : Supplier GSTIN is inactive'
		we search for string between ':' to extract the error messages
		errors = [
		        ': For inter-state transaction, CGST and SGST amounts are not applicable; only IGST amount is applicable, 3095 ',
		        ': Test'
		]
		then we trim down the message by looping over errors
		"""
		if not message:
			return []

		errors = re.findall(": [^:]+", message)
		for idx, e in enumerate(errors):
			# remove colons
			errors[idx] = errors[idx].replace(":", "").strip()
			# if not last
			if idx != len(errors) - 1:
				# remove last 7 chars eg: ', 3095 '
				errors[idx] = errors[idx][:-6]

		return errors

	def raise_error(self, raise_exception=False, errors=None):
		title = _("E Invoice Request Failed")
		if errors:
			frappe.throw(errors, title=title, as_list=1)
		else:
			link_to_error_list = '<a href="/app/error-log" target="_blank">Error Log</a>'
			frappe.msgprint(
				_(
					"An error occurred while making e-invoicing request. Please check {} for more information."
				).format(link_to_error_list),
				title=title,
				raise_exception=raise_exception,
				indicator="red",
			)

	def set_einvoice_data(self, res):
		enc_signed_invoice = res.get("SignedInvoice")
		dec_signed_invoice = jwt.decode(enc_signed_invoice, options={"verify_signature": False})["data"]

		self.invoice.irn = res.get("Irn")
		self.invoice.ewaybill = res.get("EwbNo")
		self.invoice.eway_bill_validity = res.get("EwbValidTill")
		self.invoice.ack_no = res.get("AckNo")
		self.invoice.ack_date = res.get("AckDt")
		self.invoice.signed_einvoice = dec_signed_invoice
		self.invoice.ack_no = res.get("AckNo")
		self.invoice.ack_date = res.get("AckDt")
		self.invoice.signed_qr_code = res.get("SignedQRCode")
		self.invoice.einvoice_status = "Generated"

		self.attach_qrcode_image()

		self.invoice.flags.updater_reference = {
			"doctype": self.invoice.doctype,
			"docname": self.invoice.name,
			"label": _("IRN Generated"),
		}
		self.update_invoice()

	def attach_qrcode_image(self):
		qrcode = self.invoice.signed_qr_code
		qr_image = io.BytesIO()
		url = qrcreate(qrcode, error="L")
		url.png(qr_image, scale=2, quiet_zone=1)
		qrcode_file = self.create_qr_code_file(qr_image.getvalue())
		self.invoice.qrcode_image = qrcode_file.file_url

	def create_qr_code_file(self, qr_image):
		doctype = self.invoice.doctype
		docname = self.invoice.name
		filename = "QRCode_{}.png".format(docname).replace(os.path.sep, "__")

		_file = frappe.get_doc(
			{
				"doctype": "File",
				"file_name": filename,
				"attached_to_doctype": doctype,
				"attached_to_name": docname,
				"attached_to_field": "qrcode_image",
				"is_private": 0,
				"content": qr_image,
			}
		)
		_file.save()
		frappe.db.commit()
		return _file

	def update_invoice(self):
		self.invoice.flags.ignore_validate_update_after_submit = True
		self.invoice.flags.ignore_validate = True
		self.invoice.save()

	def set_failed_status(self, errors=None):
		frappe.db.rollback()
		self.invoice.einvoice_status = "Failed"
		self.invoice.failure_description = self.get_failure_message(errors) if errors else ""
		self.update_invoice()
		frappe.db.commit()

	def get_failure_message(self, errors):
		if isinstance(errors, list):
			errors = ", ".join(errors)
		return errors


def sanitize_for_json(string):
	"""Escape JSON specific characters from a string."""

	# json.dumps adds double-quotes to the string. Indexing to remove them.
	return json.dumps(string)[1:-1]


@frappe.whitelist()
def get_einvoice(doctype, docname):
	invoice = frappe.get_doc(doctype, docname)
	return make_einvoice(invoice)


@frappe.whitelist()
def generate_irn(doctype, docname):
	gsp_connector = GSPConnector(doctype, docname)
	gsp_connector.generate_irn()


@frappe.whitelist()
def cancel_irn(doctype, docname, irn, reason, remark):
	gsp_connector = GSPConnector(doctype, docname)
	gsp_connector.cancel_irn(irn, reason, remark)


@frappe.whitelist()
def generate_qrcode(doctype, docname):
	gsp_connector = GSPConnector(doctype, docname)
	gsp_connector.fetch_and_attach_qrcode_from_irn()


@frappe.whitelist()
def generate_eway_bill(doctype, docname, **kwargs):
	gsp_connector = GSPConnector(doctype, docname)
	gsp_connector.generate_eway_bill(**kwargs)


@frappe.whitelist()
def cancel_eway_bill(doctype, docname):
	# NOTE: cancel_eway_bill api is disabled by Adequare.
	# gsp_connector = GSPConnector(doctype, docname)
	# gsp_connector.cancel_eway_bill(eway_bill, reason, remark)

	frappe.db.set_value(doctype, docname, "ewaybill", "")
	frappe.db.set_value(doctype, docname, "eway_bill_cancelled", 1)


@frappe.whitelist()
def generate_einvoices(docnames):
	docnames = json.loads(docnames) or []

	if len(docnames) < 10:
		failures = GSPConnector.bulk_generate_irn(docnames)
		frappe.local.message_log = []

		if failures:
			show_bulk_action_failure_message(failures)

		success = len(docnames) - len(failures)
		frappe.msgprint(
			_("{} e-invoices generated successfully").format(success),
			title=_("Bulk E-Invoice Generation Complete"),
		)

	else:
		enqueue_bulk_action(schedule_bulk_generate_irn, docnames=docnames)


def schedule_bulk_generate_irn(docnames):
	failures = GSPConnector.bulk_generate_irn(docnames)
	frappe.local.message_log = []

	frappe.publish_realtime(
		"bulk_einvoice_generation_complete",
		{"user": frappe.session.user, "failures": failures, "invoices": docnames},
	)


def show_bulk_action_failure_message(failures):
	for doc in failures:
		docname = '<a href="sales-invoice/{0}">{0}</a>'.format(doc.get("docname"))
		message = doc.get("message").replace("'", '"')
		if message[0] == "[":
			errors = json.loads(message)
			error_list = "".join(["<li>{}</li>".format(err) for err in errors])
			message = """{} has following errors:<br>
				<ul style="padding-left: 20px; padding-top: 5px">{}</ul>""".format(
				docname, error_list
			)
		else:
			message = "{} - {}".format(docname, message)

		frappe.msgprint(message, title=_("Bulk E-Invoice Generation Complete"), indicator="red")


@frappe.whitelist()
def cancel_irns(docnames, reason, remark):
	docnames = json.loads(docnames) or []

	if len(docnames) < 10:
		failures = GSPConnector.bulk_cancel_irn(docnames, reason, remark)
		frappe.local.message_log = []

		if failures:
			show_bulk_action_failure_message(failures)

		success = len(docnames) - len(failures)
		frappe.msgprint(
			_("{} e-invoices cancelled successfully").format(success),
			title=_("Bulk E-Invoice Cancellation Complete"),
		)
	else:
		enqueue_bulk_action(schedule_bulk_cancel_irn, docnames=docnames, reason=reason, remark=remark)


def schedule_bulk_cancel_irn(docnames, reason, remark):
	failures = GSPConnector.bulk_cancel_irn(docnames, reason, remark)
	frappe.local.message_log = []

	frappe.publish_realtime(
		"bulk_einvoice_cancellation_complete",
		{"user": frappe.session.user, "failures": failures, "invoices": docnames},
	)


def enqueue_bulk_action(job, **kwargs):
	check_scheduler_status()

	enqueue(
		job,
		**kwargs,
		queue="long",
		timeout=10000,
		event="processing_bulk_einvoice_action",
		now=frappe.conf.developer_mode or frappe.flags.in_test,
	)

	if job == schedule_bulk_generate_irn:
		msg = _("E-Invoices will be generated in a background process.")
	else:
		msg = _("E-Invoices will be cancelled in a background process.")

	frappe.msgprint(msg, alert=1)


def check_scheduler_status():
	if is_scheduler_inactive() and not frappe.flags.in_test:
		frappe.throw(_("Scheduler is inactive. Cannot enqueue job."), title=_("Scheduler Inactive"))


def job_already_enqueued(job_name):
	enqueued_jobs = [d.get("job_name") for d in get_info()]
	if job_name in enqueued_jobs:
		return True