import json
import queue
from flask import Blueprint, Response, render_template
from sqlalchemy import event

from CTFd.models import Solves, Challenges, Teams
from CTFd.utils.scores import get_standings

presenter_blueprint = Blueprint(
    "presenter",
    __name__,
    template_folder="templates"
)

listeners = []


def sse_format(data):
    return f"data: {json.dumps(data)}\n\n"


@presenter_blueprint.route("/presenter")
def presenter_view():
    return render_template("presenter.html")


@presenter_blueprint.route("/presenter/events")
def presenter_events():
    def stream():
        q = queue.Queue()
        listeners.append(q)
        try:
            while True:
                data = q.get()
                yield sse_format(data)
        except GeneratorExit:
            listeners.remove(q)

    return Response(stream(), mimetype="text/event-stream")


def broadcast(event):
    for q in listeners:
        q.put(event)


@event.listens_for(Solves, "after_insert")
def on_solve(mapper, connection, solve):
    challenge = Challenges.query.get(solve.challenge_id)
    team = Teams.query.get(solve.team_id)

    if not challenge or not team:
        return

    first_blood = False
    if Solves.query.filter_by(challenge_id=solve.challenge_id).count() == 1:
        first_blood = True

    broadcast(
        {
            "type": "solve",
            "team": team.name,
            "challenge": challenge.name,
            "value": challenge.value,
            "first": first_blood
        }
    )