# -*- 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 trytond.model import Workflow, ModelView, ModelSQL, fields, Check
from trytond.pyson import Eval
from trytond.exceptions import UserError
from trytond.i18n import gettext


STATES = {
    'readonly': Eval('state', '') != 'open',
    }
DEPENDS=['state']

sel_state_book = [
    ('open', 'Open'),
    ('closed', 'Closed'),
    ('archive', 'Archive'),
    ]


class Book(Workflow, ModelSQL, ModelView):
    'Cashbook'
    __name__ = 'cashbook.book'

    name = fields.Char(string='Name', required=True,
        states=STATES, depends=DEPENDS)
    btype = fields.Many2One(string='Type', required=True,
        model_name='cashbook.type', ondelete='RESTRICT',
        states=STATES, depends=DEPENDS)
    lines = fields.One2Many(string='Lines', field='cashbook',
        model_name='cashbook.line',
        states=STATES, depends=DEPENDS)
    state = fields.Selection(string='State', required=True,
        readonly=True, selection=sel_state_book)
    state_string = state.translated('state')

    @classmethod
    def __setup__(cls):
        super(Book, cls).__setup__()
        cls._order.insert(0, ('name', 'ASC'))
        t = cls.__table__()
        cls._sql_constraints.extend([
            ('state_val',
                Check(t, t.state.in_(['open', 'closed', 'archive'])),
                'cashbook.msg_book_wrong_state_value'),
            ])
        cls._transitions |= set((
                ('open', 'closed'),
                ('closed', 'open'),
                ('closed', 'archive'),
            ))
        cls._buttons.update({
            'wfopen': {
                'invisible': Eval('state', '') != 'closed',
                'depends': ['state'],
                },
            'wfclosed': {
                'invisible': Eval('state') != 'open',
                'depends': ['state'],
                },
            'wfarchive': {
                'invisible': Eval('state') != 'closed',
                'depends': ['state'],
                },
            })

    @classmethod
    def default_state(cls):
        return 'open'

    @classmethod
    @ModelView.button
    @Workflow.transition('open')
    def wfopen(cls, books):
        """ open cashbook
        """
        pass

    @classmethod
    @ModelView.button
    @Workflow.transition('closed')
    def wfclosed(cls, books):
        """ cashbook is closed
        """
        pass

    @classmethod
    @ModelView.button
    @Workflow.transition('archive')
    def wfarchive(cls, books):
        """ cashbook is archived
        """
        pass

    @classmethod
    def write(cls, *args):
        """ deny update if book is not 'open'
        """
        actions = iter(args)
        for books, values in zip(actions, actions):
            for book in books:
                if book.state != 'open':
                    # allow state-update, if its the only action
                    if not (('state' in values.keys()) and (len(values.keys()) == 1)):
                        raise UserError(gettext(
                            'cashbook.msg_book_deny_write',
                            bookname = book.rec_name,
                            state_txt = book.state_string,
                            ))
        super(Book, cls).write(*args)

    @classmethod
    def delete(cls, books):
        """ deny delete if book has lines
        """
        for book in books:
            if (len(book.lines) > 0) and (book.state != 'archive'):
                raise UserError(gettext(
                    'cashbook.msg_book_deny_delete',
                    bookname = book.rec_name,
                    booklines = len(book.lines),
                    ))
        return super(Book, cls).delete(books)

# end Book