# -*- coding: utf-8 -*-
##############################################################################
#
#    Copyright Camptocamp SA
#    Author Nicolas Bessi, Joel Grand-Guillaume
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
##############################################################################

from openerp.tools.translate import _
import base64
import csv
import tempfile
import datetime
from . import parser
try:
    import xlrd
except:
    raise Exception(_('Please install python lib xlrd'))

class FileParser(BankStatementImportParser):
    """Abstract clall for that help to build a specific parser for all
    .csv and .xls files"""
    
    def __init__(self, parse_name=None, keys_to_validate={}, ftype='csv', convertion_dict=None, *args, **kwargs):
        """
            :param: convertion_dict : keys and type to convert of every column in the file like 
                {
                    'ref': unicode,
                    'label': unicode,
                    'date': datetime.datetime,
                    'amount': float,
                    'commission_amount': float
                }
                
            """
        
        super(self,FileParser).__init__(parse_name, *args, **kwargs)
        if ftype in ('csv', 'xls'):
            self.ftype = ftype
        else:
            raise Exception(_('Invalide file type %s. please use csv or xls') % (ftype))
        self.keys_to_validate = keys_to_validate
        self.convertion_dict = convertion_dict

    def _custom_format(self, *args, **kwargs):
        return True

    def _pre(self, *args, **kwargs):
        return True

    def _validate(self, *args, **kwargs):
        parsed_cols = self.result_row_list[0].keys()
        for col in self.keys_to_validate:
            if col not in parsed_cols:
                raise Exception(_('Column %s not present in file') % (col))
        return True

    def _post(self, *args, **kwargs):
        """Cast row type depending on the file format .csv or .xls"""
        self.result_row_list = self._cast_rows(kwargs)
        return True

    def _parse(self, *args, **kwargs):
        """Launch the parsing through .csv or .xls depending on the
        given ftype"""
        
        res = None
        if self.ftype == 'csv':
            res = self._parse_csv()
        else:
            res = self._parse_xls()
        self.result_row_list = res
        return True

    def _parse_csv(self, delimiter=';'):
        "return an array of dict from csv file"
        csv_file = tempfile.NamedTemporaryFile()
        csv_file.write(self.filebuffer)
        # We ensure that cursor is at beginig of file
        csv_file.seek(0)
        reader = UnicodeDictReader(
                    open(csv_file.name).readlines(),
                    delimiter=delimiter
        )
        return [x for x in reader]

    def _parse_xls(self):
        "return an array of dict from xls file"
        wb_file = tempfile.NamedTemporaryFile()
        wb_file.write(self.filebuffer)
        # We ensure that cursor is at beginig of file
        wb_file.seek(0)
        wb = xlrd.open_workbook(wb_file.name)
        sheet = wb.sheet_by_index(0)
        header = sheet.row_values(0)
        res = []
        for rownum in range(1, sheet.nrows):
            res.append(dict(zip(header, sheet.row_values(rownum))))
        try:
            wb_file.close()
        except Exception, e:
            pass #file is allready closed
        return res

    def _from_csv(self, result_set, conversion_rules):
        for line in result_set:
            for rule in conversion_rules:
                if conversion_rules[rule] == datetime.datetime:
                    date_string = line[rule].split(' ')[0]
                    line[rule] = datetime.datetime.strptime(date_string,
                                                            '%Y-%m-%d')
                else:
                    line[rule] = conversion_rules[rule](line[rule])
        return result_set

    def _from_xls(self, result_set, conversion_rules):
        for line in result_set:
            for rule in conversion_rules:
                if conversion_rules[rule] == datetime.datetime:
                    t_tuple = xlrd.xldate_as_tuple(line[rule], 1)
                    line[rule] = datetime.datetime(*t_tuple)
                else:
                    line[rule] = conversion_rules[rule](line[rule])
        return result_set

    def _cast_rows(self):
        func =  getattr(self, '_from_%s'%(self.ftype))
        res = func(self.result_row_list, self.convertion_dict)
        return res