import logging
import os
import shutil
from django.conf import settings

from whoosh.fields import Schema, ID, TEXT, NUMERIC
from whoosh.index import create_in, open_dir
from whoosh.qparser import MultifieldParser
from jieba.analyse import ChineseAnalyzer

from .models import Article

log = logging.getLogger(__name__)

index_dir = os.path.join(settings.BASE_DIR, "whoosh_index")

indexer = open_dir(index_dir)


def articles_search(keyword):

  mp = MultifieldParser(
    ['content', 'title'], schema=indexer.schema, fieldboosts={'title': 5.0})
  query = mp.parse(keyword)

  with indexer.searcher() as searcher:
    results = searcher.search(query, limit=15)

    articles = []
    for hit in results:
      log.debug(hit)
      articles.append({
        'id': hit['id'],
        'slug': hit['slug'],
      })

  return articles


def rebuild():
  if os.path.exists(index_dir):
    shutil.rmtree(index_dir)
  os.makedirs(index_dir)

  analyzer = ChineseAnalyzer()
  schema = Schema(
    id=ID(stored=True, unique=True),
    slug=TEXT(stored=True),
    title=TEXT(),
    content=TEXT(analyzer=analyzer))
  indexer = create_in(index_dir, schema)

  __index_all_articles()


def __index_all_articles():
  writer = indexer.writer()
  published_articles = Article.objects.exclude(is_draft=True)
  for article in published_articles:
    writer.add_document(
      id=str(article.id),
      slug=article.slug,
      title=article.title,
      content=article.content,
    )
  writer.commit()


def article_update_index(article):
  '''
  updating an article to indexer, adding if not.
  '''
  writer = indexer.writer()
  writer.update_document(
    id=str(article.id),
    slug=article.slug,
    title=article.title,
    content=article.content,
  )

  writer.commit()


def article_delete_index(article):
  writer = indexer.writer()
  writer.delete_by_term('id', str(article.id))

  writer.commit()