# Copyright (c) 2015, Frappe Technologies Pvt. Ltd. and Contributors
# License: GNU General Public License v3. See license.txt


import json
from datetime import timedelta

import frappe
from frappe import _
from frappe.core.utils import get_parent_doc
from frappe.email.inbox import link_communication_to_document
from frappe.model.document import Document
from frappe.model.mapper import get_mapped_doc
from frappe.query_builder import Interval
from frappe.query_builder.functions import Now
from frappe.utils import date_diff, get_datetime, now_datetime, time_diff_in_seconds
from frappe.utils.user import is_website_user


class Issue(Document):
	def get_feed(self):
		return "{0}: {1}".format(_(self.status), self.subject)

	def validate(self):
		if self.is_new() and self.via_customer_portal:
			self.flags.create_communication = True

		if not self.raised_by:
			self.raised_by = frappe.session.user

		self.set_lead_contact(self.raised_by)

	def on_update(self):
		# Add a communication in the issue timeline
		if self.flags.create_communication and self.via_customer_portal:
			self.create_communication()
			self.flags.communication_created = None

	def set_lead_contact(self, email_id):
		import email.utils

		email_id = email.utils.parseaddr(email_id)[1]
		if email_id:
			if not self.lead:
				self.lead = frappe.db.get_value("Lead", {"email_id": email_id})

			if not self.contact and not self.customer:
				self.contact = frappe.db.get_value("Contact", {"email_id": email_id})

				if self.contact:
					contact = frappe.get_doc("Contact", self.contact)
					self.customer = contact.get_link_for("Customer")

			if not self.company:
				self.company = frappe.db.get_value("Lead", self.lead, "company") or frappe.db.get_default(
					"Company"
				)

	def create_communication(self):
		communication = frappe.new_doc("Communication")
		communication.update(
			{
				"communication_type": "Communication",
				"communication_medium": "Email",
				"sent_or_received": "Received",
				"email_status": "Open",
				"subject": self.subject,
				"sender": self.raised_by,
				"content": self.description,
				"status": "Linked",
				"reference_doctype": "Issue",
				"reference_name": self.name,
			}
		)
		communication.ignore_permissions = True
		communication.ignore_mandatory = True
		communication.save()

	@frappe.whitelist()
	def split_issue(self, subject, communication_id):
		# Bug: Pressing enter doesn't send subject
		from copy import deepcopy

		replicated_issue = deepcopy(self)
		replicated_issue.subject = subject
		replicated_issue.issue_split_from = self.name
		replicated_issue.first_response_time = 0
		replicated_issue.first_responded_on = None
		replicated_issue.creation = now_datetime()

		# Reset SLA
		if replicated_issue.service_level_agreement:
			replicated_issue.service_level_agreement_creation = now_datetime()
			replicated_issue.service_level_agreement = None
			replicated_issue.agreement_status = "First Response Due"
			replicated_issue.response_by = None
			replicated_issue.resolution_by = None
			replicated_issue.reset_issue_metrics()

		frappe.get_doc(replicated_issue).insert()

		# Replicate linked Communications
		# TODO: get all communications in timeline before this, and modify them to append them to new doc
		comm_to_split_from = frappe.get_doc("Communication", communication_id)
		communications = frappe.get_all(
			"Communication",
			filters={
				"reference_doctype": "Issue",
				"reference_name": comm_to_split_from.reference_name,
				"creation": (">=", comm_to_split_from.creation),
			},
		)

		for communication in communications:
			doc = frappe.get_doc("Communication", communication.name)
			doc.reference_name = replicated_issue.name
			doc.save(ignore_permissions=True)

		frappe.get_doc(
			{
				"doctype": "Comment",
				"comment_type": "Info",
				"reference_doctype": "Issue",
				"reference_name": replicated_issue.name,
				"content": " - Split the Issue from <a href='/app/Form/Issue/{0}'>{1}</a>".format(
					self.name, frappe.bold(self.name)
				),
			}
		).insert(ignore_permissions=True)

		return replicated_issue.name

	def reset_issue_metrics(self):
		self.db_set("resolution_time", None)
		self.db_set("user_resolution_time", None)


def get_list_context(context=None):
	return {
		"title": _("Issues"),
		"get_list": get_issue_list,
		"row_template": "templates/includes/issue_row.html",
		"show_sidebar": True,
		"show_search": True,
		"no_breadcrumbs": True,
	}


def get_issue_list(doctype, txt, filters, limit_start, limit_page_length=20, order_by=None):
	from frappe.www.list import get_list

	user = frappe.session.user
	contact = frappe.db.get_value("Contact", {"user": user}, "name")
	customer = None

	if contact:
		contact_doc = frappe.get_doc("Contact", contact)
		customer = contact_doc.get_link_for("Customer")

	ignore_permissions = False
	if is_website_user():
		if not filters:
			filters = {}

		if customer:
			filters["customer"] = customer
		else:
			filters["raised_by"] = user

		ignore_permissions = True

	return get_list(
		doctype, txt, filters, limit_start, limit_page_length, ignore_permissions=ignore_permissions
	)


@frappe.whitelist()
def set_multiple_status(names, status):

	for name in json.loads(names):
		frappe.db.set_value("Issue", name, "status", status)


@frappe.whitelist()
def set_status(name, status):
	frappe.db.set_value("Issue", name, "status", status)


def auto_close_tickets():
	"""Auto-close replied support tickets after 7 days"""
	auto_close_after_days = (
		frappe.db.get_value("Support Settings", "Support Settings", "close_issue_after_days") or 7
	)

	table = frappe.qb.DocType("Issue")
	issues = (
		frappe.qb.from_(table)
		.select(table.name)
		.where(
			(table.modified < (Now() - Interval(days=auto_close_after_days))) & (table.status == "Replied")
		)
	).run(pluck=True)

	for issue in issues:
		doc = frappe.get_doc("Issue", issue)
		doc.status = "Closed"
		doc.flags.ignore_permissions = True
		doc.flags.ignore_mandatory = True
		doc.save()


def has_website_permission(doc, ptype, user, verbose=False):
	from erpnext.controllers.website_list_for_contact import has_website_permission

	permission_based_on_customer = has_website_permission(doc, ptype, user, verbose)

	return permission_based_on_customer or doc.raised_by == user


def update_issue(contact, method):
	"""Called when Contact is deleted"""
	frappe.db.sql("""UPDATE `tabIssue` set contact='' where contact=%s""", contact.name)


@frappe.whitelist()
def make_task(source_name, target_doc=None):
	return get_mapped_doc("Issue", source_name, {"Issue": {"doctype": "Task"}}, target_doc)


@frappe.whitelist()
def make_issue_from_communication(communication, ignore_communication_links=False):
	"""raise a issue from email"""

	doc = frappe.get_doc("Communication", communication)
	issue = frappe.get_doc(
		{
			"doctype": "Issue",
			"subject": doc.subject,
			"communication_medium": doc.communication_medium,
			"raised_by": doc.sender or "",
			"raised_by_phone": doc.phone_no or "",
		}
	).insert(ignore_permissions=True)

	link_communication_to_document(doc, "Issue", issue.name, ignore_communication_links)

	return issue.name


def get_time_in_timedelta(time):
	"""
	Converts datetime.time(10, 36, 55, 961454) to datetime.timedelta(seconds=38215)
	"""
	return timedelta(hours=time.hour, minutes=time.minute, seconds=time.second)


def set_first_response_time(communication, method):
	if communication.get("reference_doctype") == "Issue":
		issue = get_parent_doc(communication)
		if is_first_response(issue) and issue.service_level_agreement:
			first_response_time = calculate_first_response_time(
				issue, get_datetime(issue.first_responded_on)
			)
			issue.db_set("first_response_time", first_response_time)


def is_first_response(issue):
	responses = frappe.get_all(
		"Communication", filters={"reference_name": issue.name, "sent_or_received": "Sent"}
	)
	if len(responses) == 1:
		return True
	return False


def calculate_first_response_time(issue, first_responded_on):
	issue_creation_date = issue.service_level_agreement_creation or issue.creation
	issue_creation_time = get_time_in_seconds(issue_creation_date)
	first_responded_on_in_seconds = get_time_in_seconds(first_responded_on)
	support_hours = frappe.get_cached_doc(
		"Service Level Agreement", issue.service_level_agreement
	).support_and_resolution

	if issue_creation_date.day == first_responded_on.day:
		if is_work_day(issue_creation_date, support_hours):
			start_time, end_time = get_working_hours(issue_creation_date, support_hours)

			# issue creation and response on the same day during working hours
			if is_during_working_hours(issue_creation_date, support_hours) and is_during_working_hours(
				first_responded_on, support_hours
			):
				return get_elapsed_time(issue_creation_date, first_responded_on)

			# issue creation is during working hours, but first response was after working hours
			elif is_during_working_hours(issue_creation_date, support_hours):
				return get_elapsed_time(issue_creation_time, end_time)

			# issue creation was before working hours but first response is during working hours
			elif is_during_working_hours(first_responded_on, support_hours):
				return get_elapsed_time(start_time, first_responded_on_in_seconds)

			# both issue creation and first response were after working hours
			else:
				return 1.0  # this should ideally be zero, but it gets reset when the next response is sent if the value is zero

		else:
			return 1.0

	else:
		# response on the next day
		if date_diff(first_responded_on, issue_creation_date) == 1:
			first_response_time = 0
		else:
			first_response_time = calculate_initial_frt(
				issue_creation_date, date_diff(first_responded_on, issue_creation_date) - 1, support_hours
			)

		# time taken on day of issue creation
		if is_work_day(issue_creation_date, support_hours):
			start_time, end_time = get_working_hours(issue_creation_date, support_hours)

			if is_during_working_hours(issue_creation_date, support_hours):
				first_response_time += get_elapsed_time(issue_creation_time, end_time)
			elif is_before_working_hours(issue_creation_date, support_hours):
				first_response_time += get_elapsed_time(start_time, end_time)

		# time taken on day of first response
		if is_work_day(first_responded_on, support_hours):
			start_time, end_time = get_working_hours(first_responded_on, support_hours)

			if is_during_working_hours(first_responded_on, support_hours):
				first_response_time += get_elapsed_time(start_time, first_responded_on_in_seconds)
			elif not is_before_working_hours(first_responded_on, support_hours):
				first_response_time += get_elapsed_time(start_time, end_time)

		if first_response_time:
			return first_response_time
		else:
			return 1.0


def get_time_in_seconds(date):
	return timedelta(hours=date.hour, minutes=date.minute, seconds=date.second)


def get_working_hours(date, support_hours):
	if is_work_day(date, support_hours):
		weekday = frappe.utils.get_weekday(date)
		for day in support_hours:
			if day.workday == weekday:
				return day.start_time, day.end_time


def is_work_day(date, support_hours):
	weekday = frappe.utils.get_weekday(date)
	for day in support_hours:
		if day.workday == weekday:
			return True
	return False


def is_during_working_hours(date, support_hours):
	start_time, end_time = get_working_hours(date, support_hours)
	time = get_time_in_seconds(date)
	if time >= start_time and time <= end_time:
		return True
	return False


def get_elapsed_time(start_time, end_time):
	return round(time_diff_in_seconds(end_time, start_time), 2)


def calculate_initial_frt(issue_creation_date, days_in_between, support_hours):
	initial_frt = 0
	for i in range(days_in_between):
		date = issue_creation_date + timedelta(days=(i + 1))
		if is_work_day(date, support_hours):
			start_time, end_time = get_working_hours(date, support_hours)
			initial_frt += get_elapsed_time(start_time, end_time)

	return initial_frt


def is_before_working_hours(date, support_hours):
	start_time, end_time = get_working_hours(date, support_hours)
	time = get_time_in_seconds(date)
	if time < start_time:
		return True
	return False


def get_holidays(holiday_list_name):
	holiday_list = frappe.get_cached_doc("Holiday List", holiday_list_name)
	holidays = [holiday.holiday_date for holiday in holiday_list.holidays]
	return holidays