# -*- coding: utf-8 -*-
# Copyright: Andreas Klauer <Andreas.Klauer@metamorpher.de>
# License: BSD-3

import gzip, math, random, time, html
import xml.etree.ElementTree as ET
from anki.importing.noteimp import NoteImporter, ForeignNote, ForeignCard
from anki.stdmodels import addForwardReverse

ONE_DAY = 60*60*24

class PaukerImporter(NoteImporter):
    '''Import Pauker 1.8 Lesson (*.pau.gz)'''

    needMapper = False
    allowHTML = True

    def run(self):
        model = addForwardReverse(self.col)
        model['name'] = "Pauker"
        self.col.models.save(model)
        self.col.models.setCurrent(model)
        self.model = model
        self.initMapping()
        NoteImporter.run(self)

    def fields(self):
        '''Pauker is Front/Back'''
        return 2

    def foreignNotes(self):
        '''Build and return a list of notes.'''
        notes = []

        try:
            f = gzip.open(self.file)
            tree = ET.parse(f)
            lesson = tree.getroot()
            assert lesson.tag == "Lesson"
        finally:
            f.close()

        index = -4

        for batch in lesson.findall('./Batch'):
            index += 1

            for card in batch.findall('./Card'):
                # Create a note for this card.
                front = card.findtext('./FrontSide/Text')
                back = card.findtext('./ReverseSide/Text')
                note = ForeignNote()
                note.fields = [html.escape(x.strip()).replace('\n','<br>').replace('  ',' &nbsp;') for x in [front,back]]
                notes.append(note)

                # Determine due date for cards.
                frontdue = card.find('./FrontSide[@LearnedTimestamp]')
                backdue = card.find('./ReverseSide[@Batch][@LearnedTimestamp]')

                if frontdue is not None:
                    note.cards[0] = self._learnedCard(index, int(frontdue.attrib['LearnedTimestamp']))

                if backdue is not None:
                    note.cards[1] = self._learnedCard(int(backdue.attrib['Batch']), int(backdue.attrib['LearnedTimestamp']))

        return notes

    def _learnedCard(self, batch, timestamp):
        ivl = math.exp(batch)
        now = time.time()
        due = ivl - (now - timestamp/1000.0)/ONE_DAY
        fc = ForeignCard()
        fc.due = self.col.sched.today + int(due+0.5)
        fc.ivl = random.randint(int(ivl*0.90), int(ivl+0.5))
        fc.factor = random.randint(1500,2500)
        return fc
