#
#  Copyright (c) 2015 Helmut Merz helmutm@cy55.de
#
#  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 2 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, write to the Free Software
#  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#

"""
View classes for export of report results.
"""

import csv
from cStringIO import StringIO
from zope.i18n import translate

from loops.expert.browser.report import ReportConceptView
from loops.interfaces import ILoopsObject
from loops.util import _


class ReportConceptCSVExport(ReportConceptView):

    isToplevel = True
    reportMode = 'export'

    delimiter = ';'
    encoding = 'UTF-8'

    def getFileName(self):
        return 'output'

    def getColumnTitle(self, field):
        lang = self.languageInfo.language
        return translate(_(field.title), target_language=lang)

    def __call__(self):
        fields = self.displayedColumns
        fieldNames = [f.name for f in fields]
        output = StringIO()
        writer = csv.DictWriter(output, fieldNames, delimiter=self.delimiter)
        output.write(self.delimiter.join(
                        [self.getColumnTitle(f) for f in fields]) + '\n')
        results = self.reportInstance.getResults()
        for row in results:
            data = {}
            for f in fields:
                value = f.getValue(row)
                if ILoopsObject.providedBy(value):
                    value = value.title
                if isinstance(value, unicode):
                    value = value.encode(self.encoding)
                data[f.name] = value
            writer.writerow(data)
        text = output.getvalue()
        self.setDownloadHeader(text)
        return text

    def setDownloadHeader(self, text):
        response = self.request.response
        response.setHeader('Content-Disposition',
                           'attachment; filename=%s.csv' %
                                    self.getFileName())
        response.setHeader('Cache-Control', '')
        response.setHeader('Pragma', '')
        response.setHeader('Content-Type', 'text/csv')
        response.setHeader('Content-Length', len(text))