# Copyright (c) 2022, Frappe Technologies Pvt. Ltd. and contributors
# For license information, please see license.txt

import frappe
import requests
from frappe import _
from frappe.model.document import Document
from frappe.utils import nowdate


class CurrencyExchangeSettings(Document):
	# begin: auto-generated types
	# This code is auto-generated. Do not modify anything in this block.

	from typing import TYPE_CHECKING

	if TYPE_CHECKING:
		from frappe.types import DF

		from erpnext.accounts.doctype.currency_exchange_settings_details.currency_exchange_settings_details import (
			CurrencyExchangeSettingsDetails,
		)
		from erpnext.accounts.doctype.currency_exchange_settings_result.currency_exchange_settings_result import (
			CurrencyExchangeSettingsResult,
		)

		access_key: DF.Data | None
		api_endpoint: DF.Data
		disabled: DF.Check
		req_params: DF.Table[CurrencyExchangeSettingsDetails]
		result_key: DF.Table[CurrencyExchangeSettingsResult]
		service_provider: DF.Literal["frankfurter.dev", "exchangerate.host", "frankfurter.dev - v2", "Custom"]
		url: DF.Data | None
		use_http: DF.Check
	# end: auto-generated types

	def validate(self):
		self.set_parameters_and_result()
		if frappe.in_test or frappe.flags.in_install or frappe.flags.in_setup_wizard:
			return
		response, value = self.validate_parameters()
		self.validate_result(response, value)

	def set_parameters_and_result(self):
		if self.service_provider == "exchangerate.host":
			if not self.access_key:
				frappe.throw(
					_("Access Key is required for Service Provider: {0}").format(
						frappe.bold(self.service_provider)
					)
				)

			self.set("result_key", [])
			self.set("req_params", [])

			self.api_endpoint = get_api_endpoint(self.service_provider, self.use_http)
			self.append("result_key", {"key": "result"})
			self.append("req_params", {"key": "access_key", "value": self.access_key})
			self.append("req_params", {"key": "amount", "value": "1"})
			self.append("req_params", {"key": "date", "value": "{transaction_date}"})
			self.append("req_params", {"key": "from", "value": "{from_currency}"})
			self.append("req_params", {"key": "to", "value": "{to_currency}"})
		elif self.service_provider in ("frankfurter.dev", "frankfurter.app"):
			self.set("result_key", [])
			self.set("req_params", [])

			self.api_endpoint = get_api_endpoint(self.service_provider, self.use_http)
			self.append("result_key", {"key": "rates"})
			self.append("result_key", {"key": "{to_currency}"})
			self.append("req_params", {"key": "base", "value": "{from_currency}"})
			self.append("req_params", {"key": "symbols", "value": "{to_currency}"})

		elif self.service_provider == "frankfurter.dev - v2":
			self.set("result_key", [])
			self.set("req_params", [])

			self.api_endpoint = get_api_endpoint(self.service_provider, self.use_http)
			self.append("result_key", {"key": "rate"})
			self.append("req_params", {"key": "date", "value": "{transaction_date}"})

	def validate_parameters(self):
		params = {}
		for row in self.req_params:
			params[row.key] = row.value.format(
				transaction_date=nowdate(), to_currency="INR", from_currency="USD"
			)

		api_url = self.api_endpoint.format(transaction_date=nowdate(), to_currency="INR", from_currency="USD")

		try:
			response = requests.get(api_url, params=params)
		except requests.exceptions.RequestException as e:
			frappe.throw("Error: " + str(e))

		response.raise_for_status()
		value = response.json()

		return response, value

	def validate_result(self, response, value):
		try:
			for key in self.result_key:
				value = value[
					str(key.key).format(transaction_date=nowdate(), to_currency="INR", from_currency="USD")
				]
		except Exception:
			frappe.throw(_("Invalid result key. Response:") + " " + response.text)
		if not isinstance(value, int | float):
			frappe.throw(_("Returned exchange rate is neither integer not float."))

		self.url = response.url


@frappe.whitelist()
def get_api_endpoint(service_provider: str | None = None, use_http: bool = False):
	if service_provider and service_provider in [
		"exchangerate.host",
		"frankfurter.dev",
		"frankfurter.app",
		"frankfurter.dev - v2",
	]:
		if service_provider == "exchangerate.host":
			api = "api.exchangerate.host/convert"
		elif service_provider == "frankfurter.app":
			api = "api.frankfurter.app/{transaction_date}"
		elif service_provider == "frankfurter.dev":
			api = "api.frankfurter.dev/v1/{transaction_date}"
		elif service_provider == "frankfurter.dev - v2":
			api = "api.frankfurter.dev/v2/rate/{from_currency}/{to_currency}"

		protocol = "https://"
		if use_http:
			protocol = "http://"

		return protocol + api
	return None
