# Copyright 2019 Camptocamp SA
# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
from odoo import _, api, exceptions, fields, models


class Agreement(models.Model):
    _inherit = 'agreement'

    code = fields.Char(required=False)
    sale_ids = fields.One2many(
        'sale.order', 'agreement_id', string="Sale Orders"
    )
    is_sale_agreement = fields.Boolean(
        'Sale Agreement?', compute='_compute_is_sale_agreement', store=True
    )
    is_customer_requirement = fields.Boolean('Customer requirement?')

    @api.depends('sale_ids')
    def _compute_is_sale_agreement(self):
        for rec in self:
            rec.is_sale_agreement = bool(rec.sale_ids)

    @api.model
    def _get_customer_agreement_fields(self):
        """return a list of field names which are related to customer preferences"""
        # extend the list in modules implementing specific conditions
        return []

    @api.model
    def _get_sale_agreement_fields(self):
        """return a list of field names which are related to sale conditions"""
        # extend the list in modules implementing specific conditions
        return []

    def _get_agreement_fields(self):
        return self._get_sale_agreement_fields() + \
            self._get_customer_agreement_fields()

    def template_prepare_agreement_values(self, sale_order):
        self.ensure_one()
        assert self.is_template, \
            (
                'Programming error: '
                'this method must only be called on a template agreement'
            )
        fields = ['agreement_type_id'] + self._get_sale_agreement_fields()
        tmpl_values = self.read(fields, load='_classic_write')[0]
        del tmpl_values['id']
        tmpl_values.update(
            {
                'name': self.agreement_type_id.name,
                'is_template': False,
                'is_customer_requirement': False
            }
        )
        partner = sale_order.partner_id
        customer_settings = partner.customer_agreement_settings_id
        assert not customer_settings or \
            customer_settings.is_customer_requirement, \
            'customer_settings must be a customer requirement agreement'
        if customer_settings:
            fields = self._get_customer_agreement_fields()
            cust_vals = customer_settings.read(
                fields, load='_classic_write'
            )[0]
            del cust_vals['id']
            tmpl_values.update(cust_vals)
            tmpl_values['name'] = self.agreement_type.name
        return tmpl_values

    @api.multi
    def write(self, values):
        res = super().write(values)
        if values.get('agreement_type_id'):
            self._check_agreement_type_default_agreement()
        return res

    @api.model_create_multi
    @api.returns('self', lambda value: value.id)
    def create(self, vals_list):
        res = super().create(vals_list)
        res._check_agreement_type_default_agreement()
        return res

    def _check_agreement_type_default_agreement(self):
        # if we are setting an agreement type on a template agreement then the
        # template agreement becomes the default agreement of the agreement
        # type
        template_agreements = self.filtered('is_template')
        for template in template_agreements:
            agreement_type = template.agreement_type_id
            if not agreement_type.default_agreement_id:
                agreement_type.default_agreement_id = template
            elif agreement_type.default_agreement_id == template:
                continue
            else:
                raise exceptions.UserError(
                    _('It is forbidden to have 2 templates in the '
                      'same agreement type.')
                )

    def _values_for_clear_defaults(self):
        values = {}
        for field in self._get_customer_agreement_fields():
            values[field] = False
        return values

    @api.onchange('is_template')
    def onchange_is_template(self):
        if self.is_template:
            self.unset_customer_defaults()
            self.partner_id = False

    def unset_customer_defaults(self):
        values = self._values_for_clear_defaults()
        for rec in self:
            rec.update(values)

    @api.onchange('is_customer_requirement')
    def onchange_is_customer(self):
        if self.is_customer_requirement:
            self.is_template = False
            self.set_customer_defaults()

    def _get_customer_defaults_values(self):
        ParameterValue = self.env['agreement.parameter.value']
        values = {}
        for field in self._get_customer_agreement_fields():
            values[field] = ParameterValue.get_default(field)
        return values

    def set_customer_defaults(self):
        values = self._get_customer_defaults_values()
        for rec in self:
            rec.update(values)