#!/usr/bin/env python
# -*- coding: utf-8 -*-

from django.utils.encoding import smart_unicode
from django.template.defaultfilters import slugify
import csv

def csv_open(csvfile, dialect=None):
    fh = open(csvfile, 'rb')
    if dialect is None:
        sniffer = csv.Sniffer()
        dialect = sniffer.sniff(fh.read(1024), delimiters=';,\t')
        fh.seek(0)
    reader = csv.reader(fh, dialect=dialect)
    return reader


class CSVRow(object):
    def __init__(self, field_refinition, row):
        self.row = row
        self.firstrow = field_refinition
        for i, field in enumerate(field_refinition):
            try:
                setattr(self, field, smart_unicode(row[i]))
            except IndexError:
                setattr(self, field, None)

    def __getattr__(self, name): # 'None'-fallback to make life easy
        return None
    def __repr__(self):
        ret = repr(self.__dict__) 
        return ret
    def row(self):
        return self.row


class CSVImport(object):
    def __init__(self, csvfile, dialect=None, translate=None):
        self.reader = csv_open(csvfile, dialect)
        self.rows = []
        for row in self.reader:
            self.rows.append(row)
        self.firstrow = self.rows[0]
        self.field_definition = []
        for i, field in enumerate(self.rows[0]):
            if translate:
                if field in translate:
                    print field + ' -> '+ translate[field]
                    field = translate[field]
            field = slugify(field.strip()).replace('-', '_')
            if not field:
                field = 'column_%d' % i
            self.field_definition.append(field)

    def __getitem__(self, key):
        try:
            return CSVRow(self.field_definition, self.rows[int(key) + 1])
        except (ValueError, TypeError):
            raise IndexError()

    def __iter__(self):
        for row in self.rows[1:]:
            yield CSVRow(self.field_definition, row)

    def firstrow(self):
        return self.firstrow