import os
from typing import Callable
from rethinkdb import RethinkDB
from .Condition import Condition 

RDB_HOST = os.environ.get('RETHINKDB_URL')
RDB_PORT = os.environ.get('RETHINKDB_PORT')
DB_NAME = "finfree"
TABLE_NAME = 'conditions'

r = RethinkDB()
connection = None

def get_connection():
    global connection

    if connection is None or not connection.is_open():
        connection = r.connect(RDB_HOST, RDB_PORT, db=DB_NAME)

    return connection

def getRethinkDB():
    return r

def fetch_conditions() -> list[Condition]:
    try:
        cursor = r.table(TABLE_NAME).run(get_connection())
        return [Condition(**doc) for doc in cursor] 
    except Exception as e:
        print(f"Error fetching symbols: {e}")
        return []

conditions: list[Condition] = list() 

class DbConnector:
    def watch_conditions(callback: Callable[[Condition], None]):
        global conditions

        conditions = fetch_conditions()

        for cond in conditions:
            callback(cond)

        feed = r.table(TABLE_NAME).changes().run(get_connection())
        for change in feed:
            if change['new_val'] and not change['old_val']:  # New symbol added
                cond: Condition = change['new_val']
                callback(cond)