# -*- 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 ModelView, ModelSQL, Workflow, fields, Check
from trytond.pool import Pool
from trytond.pyson import Eval, If, Or
from trytond.transaction import Transaction
from trytond.report import Report
from trytond.exceptions import UserError
from trytond.i18n import gettext
from decimal import Decimal
from sql import Cast, Literal
from sql.functions import DatePart
from sql.conditionals import Case
from .book import sel_state_book


sel_linetype = [
    ('edit', 'Edit'),
    ('check', 'Checked'),
    ('done', 'Done'),
    ]

sel_bookingtype = [
    ('in', 'Revenue'),
    ('out', 'Expense'),
    ('mvin', 'Transfer from'),
    ('mvout', 'Transfer to'),
    ]

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


class Line(Workflow, ModelSQL, ModelView):
    'Cashbook Line'
    __name__ = 'cashbook.line'

    cashbook = fields.Many2One(string='Cashbook', required=True, select=True,
        model_name='cashbook.book', ondelete='CASCADE', readonly=True)
    date = fields.Date(string='Date', required=True, select=True,
        states=STATES, depends=DEPENDS)
    month = fields.Function(fields.Integer(string='Month', readonly=True),
        'on_change_with_month', searcher='search_month')
    description = fields.Text(string='Description',
        states=STATES, depends=DEPENDS)
    category = fields.Many2One(string='Category', required=True,
        model_name='cashbook.category', ondelete='RESTRICT',
        states=STATES, depends=DEPENDS)
    category_view = fields.Function(fields.Char(string='Category', readonly=True),
        'on_change_with_category_view', searcher='search_category_view')

    bookingtype = fields.Selection(string='Type', required=True,
        help='Type of Booking', selection=sel_bookingtype,
        states=STATES, depends=DEPENDS)
    amount = fields.Numeric(string='Amount', digits=(16, Eval('currency_digits', 2)),
        required=True, states=STATES, depends=DEPENDS+['currency_digits'])
    debit = fields.Numeric(string='Debit', digits=(16, Eval('currency_digits', 2)),
        required=True, readonly=True, depends=['currency_digits'])
    credit = fields.Numeric(string='Credit', digits=(16, Eval('currency_digits', 2)),
        required=True, readonly=True, depends=['currency_digits'])
    currency = fields.Function(fields.Many2One(model_name='currency.currency',
        string="Currency"), 'on_change_with_currency')
    currency_digits = fields.Function(fields.Integer(string='Currency Digits'),
            'on_change_with_currency_digits')

    state = fields.Selection(string='State', required=True, readonly=True,
        select=True, selection=sel_linetype)
    state_string = state.translated('state')
    state_cashbook = fields.Function(fields.Selection(string='State of Cashbook',
        readonly=True, states={'invisible': True}, selection=sel_state_book),
        'on_change_with_state_cashbook', searcher='search_state_cashbook')

    #image = fields.Binary...

    @classmethod
    def __setup__(cls):
        super(Line, cls).__setup__()
        cls._order.insert(0, ('state', 'ASC'))
        cls._order.insert(0, ('date', 'ASC'))
        t = cls.__table__()
        cls._sql_constraints.extend([
            ('state_val',
                Check(t, t.state.in_(['edit', 'check', 'done'])),
                'cashbook.msg_line_wrong_state_value'),
            ])
        cls._transitions |= set((
                ('edit', 'check'),
                ('check', 'done'),
                ('check', 'edit'),
            ))
        cls._buttons.update({
            'wfedit': {
                'invisible': Eval('state', '') != 'check',
                'depends': ['state'],
                },
            'wfcheck': {
                'invisible': Eval('state') != 'edit',
                'depends': ['state'],
                },
            'wfdone': {
                'invisible': Eval('state') != 'check',
                'depends': ['state'],
                },
            })

    @classmethod
    @ModelView.button
    @Workflow.transition('edit')
    def wfedit(cls, lines):
        """ edit line
        """
        pass

    @classmethod
    @ModelView.button
    @Workflow.transition('check')
    def wfcheck(cls, lines):
        """ line is checked
        """
        pass

    @classmethod
    @ModelView.button
    @Workflow.transition('done')
    def wfdone(cls, lines):
        """ line is done
        """
        pass

    @classmethod
    def default_state(cls):
        """ default: edit
        """
        return 'edit'

    @classmethod
    def default_date(cls):
        """ default: today
        """
        IrDate = Pool().get('ir.date')
        return IrDate.today()

    @classmethod
    def default_cashbook(cls):
        """ get default from context
        """
        context = Transaction().context
        return context.get('cashbook', None)

    def get_rec_name(self, name):
        """ short + name
        """
        return '%(date)s %(desc)s' % {
            'date': Report.format_date(self.date),
            'desc': (self.description or '-')[:40],
            }

    @staticmethod
    def order_state(tables):
        """ edit = 0, check/done = 1
        """
        Line = Pool().get('cashbook.line')
        tab_line = Line.__table__()
        table, _ = tables[None]

        query = tab_line.select(
                Case(
                    (tab_line.state == 'edit', 1),
                    (tab_line.state.in_(['check', 'done']), 0),
                    else_ = 2),
                where=tab_line.id==table.id
                )
        return [query]

    @staticmethod
    def order_category_view(tables):
        """ order: name
        """
        table, _ = tables[None]
        Category = Pool().get('cashbook.category')
        tab_cat = Category.__table__()

        tab2 = tab_cat.select(tab_cat.name,
                where=tab_cat.id==table.category
            )

        return [tab2]

    @classmethod
    def search_category_view(cls, name, clause):
        """ search in category
        """
        return [('category.rec_name',) + tuple(clause[1:])]

    @fields.depends('category')
    def on_change_with_category_view(self, name=None):
        """ show optimizef form of category for list-view
        """
        Configuration = Pool().get('cashbook.configuration')
        if self.category:
            cfg1 = Configuration.get_singleton()

            if getattr(cfg1, 'catnamelong', True) == True:
                return self.category.rec_name
            else :
                return self.category.get_long_recname(self.category.name)

    @classmethod
    def search_rec_name(cls, name, clause):
        """ search in description +...
        """
        return [('description',) + tuple(clause[1:])]

    @fields.depends('date')
    def on_change_with_month(self, name=None):
        """ get difference of month to current date
        """
        IrDate = Pool().get('ir.date')
        if self.date is not None:
            dt1 = IrDate.today()
            return (12 * dt1.year + dt1.month) - \
                (12 * self.date.year + self.date.month)

    @classmethod
    def search_month(cls, names, clause):
        """ search in month
        """
        pool = Pool()
        Line = pool.get('cashbook.line')
        IrDate = pool.get('ir.date')
        tab_line = Line.__table__()
        Operator = fields.SQL_OPERATORS[clause[1]]

        dt1 = IrDate.today()
        query = tab_line.select(tab_line.id,
            where=Operator(
                Literal(12 * dt1.year + dt1.month) - \
                (Literal(12) * DatePart('year', tab_line.date) + DatePart('month', tab_line.date)),
                clause[2]),
            )
        return [('id', 'in', query)]

    @fields.depends('cashbook', '_parent_cashbook.state')
    def on_change_with_state_cashbook(self, name=None):
        """ get state of cashbook
        """
        if self.cashbook:
            return self.cashbook.state

    @classmethod
    def search_state_cashbook(cls, names, clause):
        """ search in state of cashbook
        """
        return [('cashbook.state',) + tuple(clause[1:])]

    @fields.depends('cashbook', '_parent_cashbook.currency')
    def on_change_with_currency(self, name=None):
        """ currency of cashbook
        """
        if self.cashbook:
            return self.cashbook.currency.id

    @fields.depends('cashbook', '_parent_cashbook.currency')
    def on_change_with_currency_digits(self, name=None):
        """ currency of cashbook
        """
        if self.cashbook:
            return self.cashbook.currency.digits
        else:
            return 2

    @classmethod
    def get_debit_credit(cls, values):
        """ compute debit/credit from amount
        """
        if isinstance(values, dict):
            type_ = values.get('bookingtype', None)
            amount = values.get('amount', None)
        else :
            type_ = getattr(values, 'bookingtype', None)
            amount = getattr(values, 'amount', None)

        if type_:
            if amount is not None:
                if type_ in ['in', 'mvin']:
                    return {
                        'debit': Decimal('0.0'),
                        'credit': amount,
                        }
                elif type_ in ['out', 'mvout']:
                    return {
                        'debit': amount,
                        'credit': Decimal('0.0'),
                        }
                else :
                    raise ValueError('invalid "bookingtype"')
        return {}

    @classmethod
    def create(cls, vlist):
        """ add debit/credit
        """
        vlist = [x.copy() for x in vlist]
        for vals in vlist:
            vals.update(cls.get_debit_credit(vals))
        return super(Line, cls).create(vlist)

    @classmethod
    def write(cls, *args):
        """ deny update if cashbook.line!='open',
            add or update debit/credit
        """
        actions = iter(args)
        to_write = []
        for lines, values in zip(actions, actions):
            for line in lines:
                if line.cashbook.state != 'open':
                    raise UserError(gettext(
                        'cashbook.msg_book_deny_write',
                        bookname = line.cashbook.rec_name,
                        state_txt = line.cashbook.state_string,
                        ))

            # debit / credit
            if len(set(values.keys()).intersection(set({'amount', 'bookingtype'}))) > 0:
                for line in lines:
                    values2 = {}
                    values2.update(values)
                    values2.update(cls.get_debit_credit({
                            x:values.get(x, getattr(line, x)) for x in ['amount', 'bookingtype']
                        }))
                    to_write.extend([lines, values2])
            else :
                to_write.extend([lines, values])
        super(Line, cls).write(*to_write)

    @classmethod
    def delete(cls, lines):
        """ deny delete if book is not 'open' or wf is not 'edit'
        """
        for line in lines:
            if line.cashbook.state == 'closed':
                raise UserError(gettext(
                    'cashbook.msg_line_deny_delete1',
                    linetxt = line.rec_name,
                    bookname = line.cashbook.rec_name,
                    bookstate = line.cashbook.state_string,
                    ))
            if line.state != 'edit':
                raise UserError(gettext(
                    'cashbook.msg_line_deny_delete2',
                    linetxt = line.rec_name,
                    linestate = line.state_string,
                    ))

        return super(Line, cls).delete(lines)

# end Line


class LineContext(ModelView):
    'Line Context'
    __name__ = 'cashbook.line.context'

    cashbook = fields.Many2One(string='Cashbook', required=True,
        model_name='cashbook.book',
        states={
            'readonly': Eval('num_cashbook', 0) < 2,
        }, depends=['num_cashbook'])
    date_from = fields.Date(string='Start Date', depends=['date_to'],
        domain=[
            If(Eval('date_to') & Eval('date_from'),
                ('date_from', '<=', Eval('date_to')),
                ()),
            ])
    date_to = fields.Date(string='End Date', depends=['date_from'],
        domain=[
            If(Eval('date_to') & Eval('date_from'),
                ('date_from', '<=', Eval('date_to')),
                ()),
            ])
    checked = fields.Boolean(string='Checked',
        help='Show account lines in Checked-state.')
    done = fields.Boolean(string='Done',
        help='Show account lines in Done-state.')
    num_cashbook = fields.Function(fields.Integer(string='Number of Cashbook',
        readonly=True, states={'invisible': True}),
        'on_change_with_num_cashbook')

    @classmethod
    def default_cashbook(cls):
        """ get default from context
        """
        context = Transaction().context
        return context.get('cashbook', None)

    @classmethod
    def default_date_from(cls):
        """ get default from context
        """
        context = Transaction().context
        return context.get('date_from', None)

    @classmethod
    def default_date_to(cls):
        """ get default from context
        """
        context = Transaction().context
        return context.get('date_to', None)

    @classmethod
    def default_checked(cls):
        """ get default from context
        """
        context = Transaction().context
        return context.get('checked', False)

    @classmethod
    def default_num_cashbook(cls):
        """ get default from context
        """
        CashBook = Pool().get('cashbook.book')

        with Transaction().set_context({
            '_check_access': True,
            }):
            return CashBook.search_count([])

    @classmethod
    def default_done(cls):
        """ get default from context
        """
        context = Transaction().context
        return context.get('done', False)

    def on_change_with_num_cashbook(self, name=None):
        """ get number of accessible cashbooks,
            depends on user-permissions
        """
        LineContext = Pool().get('cashbook.line.context')
        return LineContext.default_num_cashbook()

# end LineContext