# -*- coding: utf-8 -*-
# This file is part of the cashbook-module from m-ds for Tryton.
# The COPYRIGHT file at the top level of this repository contains the
# full copyright notices and license terms.

from decimal import Decimal
from trytond.model import fields
from trytond.pool import PoolMeta
from trytond.pyson import Eval, Or, If
from trytond.modules.cashbook.line import STATES, DEPENDS


class Line(metaclass=PoolMeta):
    __name__ = 'cashbook.line'

    quantity = fields.Numeric(string='Quantity',
        digits=(16, Eval('quantity_digits', 4)),
        states={
            'required': Or(
                    Eval('feature', '') == 'asset',
                    Eval('booktransf_feature', '') == 'asset',
                ),
            'invisible': ~Or(
                    Eval('feature', '') == 'asset',
                    Eval('booktransf_feature', '') == 'asset',
                ),
            'readonly': Or(
                STATES['readonly'],
                Eval('bookingtype', '').in_(['spin', 'spout']),
                ),
        }, depends=DEPENDS+['feature', 'booktransf_feature',
            'quantity_digits', 'bookingtype'])
    quantity_digits = fields.Function(fields.Integer(string='Digits',
        readonly=True, states={'invisible': True}),
        'on_change_with_quantity_digits')
    quantity_uom = fields.Function(fields.Many2One(string='Symbol',
        readonly=True, model_name='product.uom'),
        'on_change_with_quantity_uom')
    asset_rate = fields.Function(fields.Numeric(string='Rate',
        readonly=True,
        digits=(16, If(
            Eval('currency_digits', 2) > Eval('quantity_digits', 2),
            Eval('currency_digits', 2), Eval('quantity_digits', 2))),
        states={
            'invisible': Eval('feature', '') != 'asset',
        }, depends=['currency_digits', 'quantity_digits', 'feature']),
        'on_change_with_asset_rate')

    @classmethod
    def get_counterpart_values(cls, line, values={}):
        """ add quantity to counterpart
        """
        result = super(Line, cls).get_counterpart_values(line, values)
        result['quantity'] = line.quantity
        return result

    @fields.depends('quantity', 'amount', 'currency_digits', 'quantity_digits')
    def on_change_with_asset_rate(self, name=None):
        """ get rate
        """
        if (self.quantity is None) or (self.amount is None):
            return
        digit = max(
            self.currency_digits if self.currency_digits is not None else 2,
            self.quantity_digits if self.quantity_digits is not None else 4)
        if self.quantity != Decimal('0.0'):
            return (
                    self.amount / self.quantity
                ).quantize(Decimal(str(1/10**digit)))

    @fields.depends('cashbook', '_parent_cashbook.quantity_uom')
    def on_change_with_quantity_uom(self, name=None):
        """ get quantity-unit of asset
        """
        if self.cashbook:
            if self.cashbook.quantity_uom:
                return self.cashbook.quantity_uom.id

    @fields.depends('cashbook', '_parent_cashbook.quantity_digits')
    def on_change_with_quantity_digits(self, name=None):
        """ get digits from cashbook
        """
        if self.cashbook:
            return self.cashbook.quantity_digits
        return 4

# end LineContext