# This file is part of Tryton.  The COPYRIGHT file at the toplevel of this
# repository contains the full copyright notices and license terms.
import json
from sql import Query, Expression

from .field import Field, SQLType
from ...protocols.jsonrpc import JSONDecoder, JSONEncoder
from ...pool import Pool
from ...tools import grouped_slice


class Dict(Field):
    'Define dict field.'
    _type = 'dict'

    def __init__(self, schema_model, string='', help='', required=False,
            readonly=False, domain=None, states=None, select=False,
            on_change=None, on_change_with=None, depends=None,
            context=None, loading='lazy'):
        super(Dict, self).__init__(string, help, required, readonly, domain,
            states, select, on_change, on_change_with, depends, context,
            loading)
        self.schema_model = schema_model

    def get(self, ids, model, name, values=None):
        dicts = dict((id, None) for id in ids)
        for value in values or []:
            if value[name]:
                dicts[value['id']] = json.loads(value[name],
                    object_hook=JSONDecoder())
        return dicts

    @staticmethod
    def sql_format(value):
        if isinstance(value, (Query, Expression)):
            return value
        if value is None:
            return None
        assert isinstance(value, dict)
        return json.dumps(value, cls=JSONEncoder)

    def sql_type(self):
        return SQLType('TEXT', 'TEXT')

    def translated(self, name=None, type_='values'):
        "Return a descriptor for the translated value of the field"
        if name is None:
            name = self.name
        if name is None:
            raise ValueError('Missing name argument')
        return TranslatedDict(name, type_)


class TranslatedDict(object):
    'A descriptor for translated values of Dict field'

    def __init__(self, name, type_):
        assert type_ in ['keys', 'values']
        self.name = name
        self.type_ = type_

    def __get__(self, inst, cls):
        if inst is None:
            return self
        pool = Pool()
        schema_model = getattr(cls, self.name).schema_model
        SchemaModel = pool.get(schema_model)

        value = getattr(inst, self.name)
        if not value:
            return value

        domain = []
        if self.type_ == 'values':
            domain = [('type_', '=', 'selection')]

        records = []
        for key_names in grouped_slice(value.keys()):
            records += SchemaModel.search([
                    ('name', 'in', key_names),
                    ] + domain)
        keys = SchemaModel.get_keys(records)

        if self.type_ == 'keys':
            return {k['name']: k['string'] for k in keys}

        elif self.type_ == 'values':
            trans = {k['name']: dict(k['selection']) for k in keys}
            return {k: v if k not in trans else trans[k].get(v, v)
                for k, v in value.iteritems()}
