import re
import dateutil.parser

from flask import request, g
from flask.ext.restful import Resource, reqparse

from pyaggr3g470r.models import Article, Feed
from pyaggr3g470r.controllers import ArticleController
from pyaggr3g470r.views.api.common import authenticate, to_response, \
                                          PyAggResource


class ArticleListAPI(Resource):
    """
    Defines a RESTful API for Article elements.
    """
    method_decorators = [authenticate, to_response]

    def __init__(self):
        self.reqparse = reqparse.RequestParser()
        self.reqparse.add_argument('title', type=unicode, location='json')
        self.reqparse.add_argument('content', type=unicode, location='json')
        self.reqparse.add_argument('link', type=unicode, location='json')
        self.reqparse.add_argument('date', type=str, location='json')
        self.reqparse.add_argument('feed_id', type=int, location='json')
        super(ArticleListAPI, self).__init__()

    def get(self):
        """
        Returns a list of articles.
        """
        feeds = {feed.id: feed.title for feed in g.user.feeds if feed.enabled}
        articles = Article.query.filter(Article.feed_id.in_(feeds.keys()),
                                        Article.user_id == g.user.id)
        filter_ = request.args.get('filter_', 'unread')
        feed_id = int(request.args.get('feed', 0))
        limit = request.args.get('limit', 1000)
        if filter_ != 'all':
            articles = articles.filter(Article.readed == (filter_ == 'read'))
        if feed_id:
            articles = articles.filter(Article.feed_id == feed_id)

        articles = articles.order_by(Article.date.desc())
        if limit != 'all':
            limit = int(limit)
            articles = articles.limit(limit)

        return {'result': [article.dump() for article in articles]}

    def post(self):
        """
        POST method - Create a new article.
        """
        args = self.reqparse.parse_args()
        article_dict = {}
        for k, v in args.iteritems():
            if v != None:
                article_dict[k] = v
            else:
                return {"message": "Missing argument: %s." % (k,)}, 400
        article_date = None
        try:
            article_date = dateutil.parser.parse(article_dict["date"], dayfirst=True)
        except:
            try:  # trying to clean date field from letters
                article_date = dateutil.parser.parse(re.sub('[A-z]', '', article_dict["date"], dayfirst=True))
            except:
                return {"message": "Bad format for the date."}, 400
        article = Article(link=article_dict["link"], title=article_dict["title"],
                                content=article_dict["content"], readed=False, like=False,
                                date=article_date, user_id=g.user.id,
                                feed_id=article_dict["feed_id"])
        feed = Feed.query.filter(Feed.id == article_dict["feed_id"], Feed.user_id == g.user.id).first()
        feed.articles.append(article)
        try:
            g.db.session.commit()
            return {"message": "ok"}, 201
        except:
            return {"message": "Impossible to create the article."}, 500


class ArticleAPI(PyAggResource):
    "Defines a RESTful API for Article elements."
    method_decorators = [authenticate, to_response]
    controller_cls = ArticleController
    editable_attrs = ['like', 'readed']

    def __init__(self):
        self.reqparse = reqparse.RequestParser()
        self.reqparse.add_argument('like', type=bool, location='json')
        self.reqparse.add_argument('readed', type=bool, location= 'json')
        super(ArticleAPI, self).__init__()


g.api.add_resource(ArticleListAPI, '/articles', endpoint='articles.json')
g.api.add_resource(ArticleAPI, '/articles/<int:obj_id>',
                 endpoint='article.json')