#This file is part of Tryton.  The COPYRIGHT file at the top level of this repository contains the full copyright notices and license terms.
"Statement"

from trytond.osv import fields, OSV
from trytond.netsvc import LocalService
from decimal import Decimal
import datetime

_STATES = {'readonly': 'state != "draft"'}


class Statement(OSV):
    'Account Statement'
    _name = 'account.statement'
    _description = __doc__

    journal = fields.Many2One('account.statement.journal', 'Journal', required=True,
            states=_STATES, on_change=['journal'], select=1)
    date = fields.Date('Date', required=True, states=_STATES, select=1)
    start_balance = fields.Numeric('Start Balance', digits=(16, 2),
            states=_STATES)
    end_balance = fields.Numeric('End Balance', digits=(16, 2), states=_STATES)
    lines = fields.One2Many('account.statement.line', 'statement',
            'Transactions', states=_STATES)
    state = fields.Selection([
        ('draft', 'Draft'),
        ('validated', 'Validated'),
        ('cancel', 'Cancel'),
        ('posted', 'Posted'),
        ], 'State', readonly=True, select=1)
    move_lines = fields.Function('get_move_lines', type='one2many',
            relation='account.move.line', string='Move Lines')

    def __init__(self):
        super(Statement, self).__init__()
        self._rpc_allowed += [
            'draft_workflow',
        ]
        self._order[0] = ('id', 'DESC')
        self._error_messages.update({
            'wrong_end_balance': 'Wrong End balance:\n' \
                    ' * Expected: %s\n' \
                    ' * Computed: %s',
            })

    def default_state(self, cursor, user, context=None):
        return 'draft'

    def default_date(self, cursor, user, context=None):
        return datetime.date.today()

    def on_change_journal(self, cursor, user, ids, value, context=None):
        res = {}
        if not value.get('journal'):
            return res

        statement_ids = self.search(cursor, user, [
            ('journal', '=', value['journal']),
            ], order=[
                ('date', 'DESC'),
            ], limit=1, context=context)
        if not statement_ids:
            return res

        statement = self.browse(cursor, user, statement_ids[0], context=context)
        res['start_balance'] = statement.end_balance
        return res

    def get_move_lines(self, cursor, user, ids, name, args, context=None):
        '''
        Return the move lines that have been generated by the statements.
        '''
        res = {}
        for statement in self.browse(cursor, user, ids, context=context):
            res[statement.id] = []
            for line in statement.lines:
                if not line.move:
                    continue
                for move_line in line.move.lines:
                    res[statement.id].append(move_line.id)
        return res

    def get_end_balance(self, cursor, user, ids, name, arg, context=None):
        statements = self.browse(cursor, user, ids, context=context)
        res = {}
        for statement in statements:
            res[statement.id] = statement.start_balance
            for line in statement.lines:
                res[statement.id] += line.amount
        return res

    def set_state_validated(self, cursor, user, statement_id, context=None):
        statement_line_obj = self.pool.get('account.statement.line')

        statement = self.browse(cursor, user, statement_id, context=context)

        computed_end_balance = statement.start_balance
        for line in statement.lines:
            computed_end_balance += line.amount
        if computed_end_balance != statement.end_balance:
            self.raise_user_error(cursor, 'wrong_end_balance',
                    (statement.end_balance, computed_end_balance),
                    context=context)
        for line in statement.lines:
            statement_line_obj.create_move(cursor, user, line, context=context)
        self.write(cursor, user, statement_id, {
            'state':'validated',
            }, context=context)

    def set_state_posted(self, cursor, user, statement_id, context=None):
        statement_line_obj = self.pool.get('account.statement.line')

        statement = self.browse(cursor, user, statement_id, context=context)
        statement_line_obj.post_move(cursor, user, statement.lines,
                context=context)
        self.write(cursor, user, statement_id, {
            'state':'posted',
            }, context=context)

    def set_state_cancel(self, cursor, user, statement_id, context=None):
        statement_line_obj = self.pool.get('account.statement.line')

        statement = self.browse(cursor, user, statement_id, context=context)
        statement_line_obj.delete_move(cursor, user, statement.lines,
                context=context)
        self.write(cursor, user, statement_id, {
            'state':'cancel',
            }, context=context)

    def draft_workflow(self, cursor, user, ids, context=None):
        workflow_service = LocalService('workflow')
        for statement in self.browse(cursor, user, ids, context=context):
            workflow_service.trg_create(user, self._name, statement.id, cursor)
            self.write(cursor, user, statement.id, {
                'state': 'draft',
                }, context=context)
        return True

Statement()


class Line(OSV):
    'Account Statement Line'
    _name = 'account.statement.line'
    _description = __doc__

    statement = fields.Many2One('account.statement', 'Statement',
            required=True, ondelete='CASCADE')
    date = fields.Date('Date', required=True)
    amount = fields.Numeric('Amount', digits=(16,2), required=True,
        on_change=['amount', 'party', 'account'])
    party = fields.Many2One('relationship.party', 'Party',
            on_change=['amount', 'party'])
    account = fields.Many2One('account.account', 'Account', required=True)
    description = fields.Char('Description')
    move = fields.Many2One('account.move', 'Account Move', readonly=True)

    def __init__(self):
        super(Line, self).__init__()
        self._error_messages.update({
            'debit_credit_account_bank_journal': 'Please provide debit and ' \
                    'credit account on bank journal.',
            })

    def on_change_party(self, cursor, user, ids, value, context=None):
        res = {}
        if not (value.get('party') and value.get('amount')):
            return res
        party_obj = self.pool.get('relationship.party')
        account_obj = self.pool.get('account.account')
        party = party_obj.browse(cursor, user, value['party'], context=context)
        if value['amount'] > Decimal("0.0"):
            account = party.account_receivable
        else:
            account = party.account_payable
        res['account'] = account_obj.name_get(cursor, user, account.id,
                context=context)[0]
        return res

    def on_change_amount(self, cursor, user, ids, value, context=None):
        res = {}
        if not (value.get('party') and value.get('amount')):
            return res
        party_obj = self.pool.get('relationship.party')
        account_obj = self.pool.get('account.account')
        party = party_obj.browse(cursor, user, value['party'], context=context)
        if value.get('account') and value['account'] not in (
            party.account_receivable.id, party.account_payable.id):
            # The user has entered a non-default value, we keep it.
            return res
        if value['amount'] > Decimal("0.0"):
            account = party.account_receivable
        else:
            account = party.account_payable
        res['account'] = account_obj.name_get(cursor, user, account.id,
                context=context)[0]
        return res

    def create_move(self, cursor, user, line, context=None):
        move_obj = self.pool.get('account.move')
        period_obj = self.pool.get('account.period')
        period_id = period_obj.find(cursor, user,
                line.statement.journal.company.id, date=line.date,
                context=context)

        move_lines = self.get_move_lines(cursor, user, line, context=context)
        move_id = move_obj.create(cursor, user, {
                'name': line.date,
                'period': period_id,
                'journal': line.statement.journal.journal.id,
                'date': line.date,
                'lines': [('create', x) for x in move_lines],
             }, context=context)
        self.write(cursor, user, line.id, {
            'move': move_id,
            }, context=context)

    def post_move(self, cursor, user, lines, context=None):
        move_obj = self.pool.get('account.move')
        move_obj.post(cursor, user, [l.move.id for l in lines], context=context)

    def delete_move(self, cursor, user, lines, context=None):
        move_obj = self.pool.get('account.move')
        move_obj.delete(cursor, user, [l.move.id for l in lines],
                context=context)

    def get_move_lines(self, cursor, user, statement_line, context=None):
        currency_obj = self.pool.get('currency.currency')
        zero = Decimal("0.0")
        amount = currency_obj.compute(
            cursor, user, statement_line.statement.journal.currency,
            statement_line.amount,
            statement_line.statement.journal.company.currency, context=context)
        if statement_line.statement.journal.currency.id != \
                statement_line.statement.journal.company.currency.id:
            second_currency = statement_line.statement.journal.currency.id
            amount_second_currency = abs(statement_line.amount)
        else:
            amount_second_currency = False
            second_currency = None

        vals = []
        vals.append({
            'name': statement_line.date,
            'debit': amount < zero and -amount or zero,
            'credit': amount >= zero and amount or zero,
            'account': statement_line.account.id,
            'party': statement_line.party and statement_line.party.id,
            'second_currency': second_currency,
            'amount_second_currency': amount_second_currency,
            })

        journal = statement_line.statement.journal.journal
        if statement_line.amount >= zero:
            account = journal.credit_account
        else:
            account = journal.debit_account
        if not account:
            self.raise_user_error(cursor, 'debit_credit_account_bank_journal',
                    context=context)
        vals.append({
            'name': statement_line.date,
            'debit': amount >= zero and amount or zero,
            'credit': amount < zero and -amount or zero,
            'account': account.id,
            'party': statement_line.party and statement_line.party.id,
            'second_currency': second_currency,
            'amount_second_currency': amount_second_currency,
            })
        return vals

Line()