from datetime import date
from decimal import Decimal, InvalidOperation

from django.db.models import Sum
from django.template.loader import render_to_string
from liveview import liveview_handler, send

from app.monthly.services import update_budget
from app.monthly.models import Income


def _render_income_table(year, month, editing_id=None):
	incomes = Income.objects.filter(
		date__year=year,
		date__month=month,
	)
	total = incomes.aggregate(total=Sum("amount"))["total"] or Decimal("0")
	return render_to_string(
		"pages/monthly/partials/income_table.html",
		{
			"incomes": incomes,
			"total": total,
			"year": year,
			"month": month,
			"today": date.today().isoformat(),
			"editing_id": editing_id,
		},
	)


@liveview_handler("add_income")
def add_income(consumer, content):
	form = content.get("form", {})
	year = int(form.get("year", 0))
	month = int(form.get("month", 0))
	concept = form.get("income_concept", "").strip()
	amount_raw = form.get("income_amount", "").replace(",", ".")
	date_raw = form.get("income_date", "")

	if not concept or not amount_raw or not date_raw or not year or not month:
		return

	try:
		amount = Decimal(amount_raw)
		income_date = date.fromisoformat(date_raw)
	except (InvalidOperation, ValueError):
		return

	Income.objects.create(
		date=income_date,
		concept=concept,
		amount=amount,
	)

	html = _render_income_table(year, month)
	send(consumer, {"target": "#income-table", "html": html})
	update_budget(consumer, year, month)


@liveview_handler("delete_income")
def delete_income(consumer, content):
	data = content.get("data", {})
	income_id = data.get("data_id", "")
	year = int(data.get("data_year", 0))
	month = int(data.get("data_month", 0))

	if not income_id or not year or not month:
		return

	Income.objects.filter(id=income_id).delete()

	html = _render_income_table(year, month)
	send(consumer, {"target": "#income-table", "html": html})
	update_budget(consumer, year, month)


@liveview_handler("edit_income")
def edit_income(consumer, content):
	data = content.get("data", {})
	income_id = data.get("data_id", "")
	year = int(data.get("data_year", 0))
	month = int(data.get("data_month", 0))

	if not income_id:
		return

	try:
		income = Income.objects.get(id=income_id)
	except Income.DoesNotExist:
		return

	html = _render_income_table(year, month, editing_id=income.id)
	send(consumer, {"target": "#income-table", "html": html})


@liveview_handler("cancel_edit_income")
def cancel_edit_income(consumer, content):
	data = content.get("data", {})
	year = int(data.get("data_year", 0))
	month = int(data.get("data_month", 0))

	if not year or not month:
		return

	html = _render_income_table(year, month)
	send(consumer, {"target": "#income-table", "html": html})


@liveview_handler("save_income")
def save_income(consumer, content):
	form = content.get("form", {})
	income_id = form.get("income_id", "")
	year = int(form.get("year", 0))
	month = int(form.get("month", 0))
	concept = form.get("income_concept", "").strip()
	amount_raw = form.get("income_amount", "").replace(",", ".")
	date_raw = form.get("income_date", "")

	if not income_id or not concept or not amount_raw or not date_raw:
		return

	try:
		amount = Decimal(amount_raw)
		income_date = date.fromisoformat(date_raw)
		income = Income.objects.get(id=income_id)
	except (InvalidOperation, ValueError, Income.DoesNotExist):
		return

	income.date = income_date
	income.concept = concept
	income.amount = amount
	income.save()

	html = _render_income_table(year, month)
	send(consumer, {"target": "#income-table", "html": html})
	update_budget(consumer, year, month)


@liveview_handler("clone_income")
def clone_income(consumer, content):
	form = content.get("form", {})
	source = form.get("clone_source", "")
	year = int(form.get("year", 0))
	month = int(form.get("month", 0))

	if not source or not year or not month:
		return

	try:
		src_year, src_month = source.split("-")
		src_year, src_month = int(src_year), int(src_month)
	except ValueError:
		return

	source_incomes = Income.objects.filter(
		date__year=src_year,
		date__month=src_month,
	)

	today = date.today()
	for inc in source_incomes:
		Income.objects.create(
			date=today,
			concept=inc.concept,
			amount=inc.amount,
		)

	html = _render_income_table(year, month)
	send(consumer, {"target": "#income-table", "html": html})
	update_budget(consumer, year, month)