import { USE_INVITE_KEYS } from "../config";
import type { AllContext } from "../types";
import { has } from "./helpers";

export const isUsingInviteKeys = (c: AllContext): boolean => {
  return has(c.env, "INVITE_POOL") && USE_INVITE_KEYS;
};

export const doesInviteKeyHaveValues = async (c: AllContext, inviteKey: string | undefined): Promise<boolean> => {
  if (isUsingInviteKeys(c)) {
    if (inviteKey === undefined)
      return false;

    const value = await c.env.INVITE_POOL.get(inviteKey);
    // Key does not exist
    if (value === null)
      return false;

    // check the amount we have
    const amount: number = parseInt(value);

    // nans are failure
    if (isNaN(amount))
      return false;

    // -1 means infinite invites
    if (amount === -1 || amount >= 1)
      return true;
    else
      return false;
  }
  return true;
};

export const consumeInviteKey = async (c: AllContext, inviteKey: string | undefined) => {
  if (isUsingInviteKeys(c)) {
    if (inviteKey === undefined)
      return;

    const value = await c.env.INVITE_POOL.get(inviteKey);
    if (value === null) {
      console.error(`attempted to use invite key ${inviteKey} but is invalid`);
      return;
    }
    // check the amount we have
    const amount: number = parseInt(value);

    // handle NaN
    if (isNaN(amount)) {
      console.warn(`${inviteKey} has the value of ${value} which triggers NaN.`);
      return;
    }

    // -1 has infinite invites
    if (amount === -1)
      return;

    const newValue: number = amount - 1;
    // Delete any keys that fall to 0, they should be removed from the db
    if (newValue <= 0) {
      await c.env.INVITE_POOL.delete(inviteKey);
      return;
    }

    // put the new value on the stack
    await c.env.INVITE_POOL.put(inviteKey, newValue.toString());
  }
};