from app import cache
from app.api.alpha.views import post_view
from app.api.alpha.utils.validators import required, integer_expected, boolean_expected
from app.models import Post, Community, CommunityMember, utcnow
from app.shared.post import vote_for_post, bookmark_the_post, remove_the_bookmark_from_post, toggle_post_notification
from app.utils import authorise_api_user, blocked_users, blocked_communities, blocked_instances, community_ids_from_instances

from datetime import timedelta
from sqlalchemy import desc


@cache.memoize(timeout=3)
def cached_post_list(type, sort, user_id, community_id, community_name, person_id):
    if type == "All":
        if community_name:
            name, ap_domain = community_name.split('@')
            posts = Post.query.filter_by(deleted=False).join(Community, Community.id == Post.community_id).filter_by(show_all=True, name=name, ap_domain=ap_domain)
        elif community_id:
            posts = Post.query.filter_by(deleted=False).join(Community, Community.id == Post.community_id).filter_by(show_all=True, id=community_id)
        elif person_id:
            posts = Post.query.filter_by(deleted=False, user_id=person_id)
        else:
            posts = Post.query.filter_by(deleted=False).join(Community, Community.id == Post.community_id).filter_by(show_all=True)
    elif type == "Local":
        posts = Post.query.filter_by(deleted=False).join(Community, Community.id == Post.community_id).filter_by(ap_id=None)
    elif type == "Popular":
        posts = Post.query.filter_by(deleted=False).join(Community, Community.id == Post.community_id).filter(Community.show_popular == True, Post.score > 100)
    elif type == "Subscribed" and user_id is not None:
        posts = Post.query.filter_by(deleted=False).join(CommunityMember, Post.community_id == CommunityMember.community_id).filter_by(is_banned=False, user_id=user_id)
    else:
        posts = Post.query.filter_by(deleted=False)

    if user_id is not None:
        blocked_person_ids = blocked_users(user_id)
        if blocked_person_ids:
            posts = posts.filter(Post.user_id.not_in(blocked_person_ids))
        blocked_community_ids = blocked_communities(user_id)
        if blocked_community_ids:
            posts = posts.filter(Post.community_id.not_in(blocked_community_ids))
        blocked_instance_ids = blocked_instances(user_id)
        if blocked_instance_ids:
            posts = posts.filter(Post.instance_id.not_in(blocked_instance_ids))                                         # users from blocked instance
            posts = posts.filter(Post.community_id.not_in(community_ids_from_instances(blocked_instance_ids)))          # communities from blocked instance

    if sort == "Hot":
        posts = posts.order_by(desc(Post.ranking)).order_by(desc(Post.posted_at))
    elif sort == "TopDay":
        posts = posts.filter(Post.posted_at > utcnow() - timedelta(days=1)).order_by(desc(Post.up_votes - Post.down_votes))
    elif sort == "New":
        posts = posts.order_by(desc(Post.posted_at))
    elif sort == "Active":
        posts = posts.order_by(desc(Post.last_active))

    return posts.all()


def get_post_list(auth, data, user_id=None):
    type = data['type_'] if data and 'type_' in data else "All"
    sort = data['sort'] if data and 'sort' in data else "Hot"
    page = int(data['page']) if data and 'page' in data else 1
    limit = int(data['limit']) if data and 'limit' in data else 10

    if auth:
        user_id = authorise_api_user(auth)

    # user_id: the logged in user
    # person_id: the author of the posts being requested

    community_id = int(data['community_id']) if data and 'community_id' in data else None
    community_name = data['community_name'] if data and 'community_name' in data else None
    person_id = int(data['person_id']) if data and 'person_id' in data else None

    posts = cached_post_list(type, sort, user_id, community_id, community_name, person_id)

    start = (page - 1) * limit
    end = start + limit
    posts = posts[start:end]

    postlist = []
    for post in posts:
        try:
            postlist.append(post_view(post=post, variant=2, stub=True, user_id=user_id))
        except:
            continue
    list_json = {
        "posts": postlist
    }

    return list_json


def get_post(auth, data):
    if not data or 'id' not in data:
        raise Exception('missing_parameters')

    id = int(data['id'])

    user_id = authorise_api_user(auth) if auth else None

    post_json = post_view(post=id, variant=3, user_id=user_id)
    return post_json


# would be in app/constants.py
SRC_API = 3

def post_post_like(auth, data):
    required(['post_id', 'score'], data)
    integer_expected(['post_id', 'score'], data)

    post_id = data['post_id']
    score = data['score']
    if score == 1:
        direction = 'upvote'
    elif score == -1:
        direction = 'downvote'
    else:
        score = 0
        direction = 'reversal'

    user_id = vote_for_post(post_id, direction, SRC_API, auth)
    cache.delete_memoized(cached_post_list)
    post_json = post_view(post=post_id, variant=4, user_id=user_id, my_vote=score)
    return post_json


def put_post_save(auth, data):
    required(['post_id', 'save'], data)
    integer_expected(['post_id'], data)
    boolean_expected(['save'], data)

    post_id = data['post_id']
    save = data['save']

    user_id = bookmark_the_post(post_id, SRC_API, auth) if save else remove_the_bookmark_from_post(post_id, SRC_API, auth)
    post_json = post_view(post=post_id, variant=4, user_id=user_id)
    return post_json


def put_post_subscribe(auth, data):
    required(['post_id', 'subscribe'], data)
    integer_expected(['post_id'], data)
    boolean_expected(['subscribe'], data)

    post_id = data['post_id']
    subscribe = data['subscribe']           # not actually processed - is just a toggle

    user_id = toggle_post_notification(post_id, SRC_API, auth)
    post_json = post_view(post=post_id, variant=4, user_id=user_id)
    return post_json