"""App setup: custom fields created/synced on migrate."""

import frappe
from frappe.custom.doctype.custom_field.custom_field import create_custom_fields
from frappe.custom.doctype.property_setter.property_setter import make_property_setter

from ns_app.api.statements import BILLED_UPTO_FIELD, LATE_FEE_NAMING_SERIES

# Fee schedule/amounts live on ERPNext's Dunning Type; this adds the one thing
# it lacks — the Item used to bill a late fee as a Sales Invoice.
CUSTOM_FIELDS = {
    "Dunning Type": [
        {
            "fieldname": "custom_late_fee_item",
            "label": "Late Fee Item",
            "fieldtype": "Link",
            "options": "Item",
            "insert_after": "income_account",
            "description": (
                "Item used to bill a late-payment fee as a Sales Invoice when "
                "customer statements are generated."
            ),
        }
    ],
    "Sales Invoice": [
        {
            "fieldname": BILLED_UPTO_FIELD,
            "label": "Late Fee Billed Upto",
            "fieldtype": "Date",
            "insert_after": "due_date",
            "read_only": 1,
            "print_hide": 1,
            # Must survive frappe.copy_doc() when the invoice is amended to add
            # another period's interest — it is what stops that period being
            # billed twice.
            "no_copy": 0,
            "description": (
                "On a late-fee invoice, the date interest was last charged. The "
                "next statement run accrues interest from here."
            ),
        }
    ],
}


def _register_late_fee_naming_series():
    """Add the late-fee series to Sales Invoice's naming_series options."""
    field = frappe.get_meta("Sales Invoice").get_field("naming_series")
    options = [o for o in (field.options or "").split("\n")] if field else []
    if LATE_FEE_NAMING_SERIES not in options:
        options.append(LATE_FEE_NAMING_SERIES)
        make_property_setter(
            "Sales Invoice",
            "naming_series",
            "options",
            "\n".join(options),
            "Text",
            validate_fields_for_doctype=False,
        )


def after_migrate():
    create_custom_fields(CUSTOM_FIELDS)
    _register_late_fee_naming_series()