type ConnectedCallback = (component: ConnectedComponent) => void;

export type ConnectedComponent = Record<string, unknown> & {
  __onConnected__: (callback: ConnectedCallback) => void;
  __onDisconnected__: (callback: ConnectedCallback) => void;
  __connectedCallbackCalls__?: Set<ConnectedCallback>;
  __disconnectedCallbackCalls__?: Set<ConnectedCallback>;
};

function onConnected(this: ConnectedComponent, callback: ConnectedCallback) {
  if (!this.__connectedCallbackCalls__) {
    this.__connectedCallbackCalls__ = new Set();
  }
  this.__connectedCallbackCalls__.add(callback);
}

function onDisconnected(this: ConnectedComponent, callback: ConnectedCallback) {
  if (!this.__disconnectedCallbackCalls__) {
    this.__disconnectedCallbackCalls__ = new Set();
  }
  this.__disconnectedCallbackCalls__.add(callback);
}

export function setSubscribable(target: any) {
  if (target.__is__setSubscribable__) return;
  target.__is__setSubscribable__ = true;

  target.__onConnected__ = onConnected;
  target.__onDisconnected__ = onDisconnected;

  const originalConnectedCallback = target.connectedCallback;
  target.connectedCallback = function (this: any) {
    originalConnectedCallback?.call(this);
    if (this.__connectedCallbackCalls__) {
      this.__connectedCallbackCalls__.forEach((callback: ConnectedCallback) =>
        callback(this)
      );
    }
  };

  const originalDisconnectedCallback = target.disconnectedCallback;
  target.disconnectedCallback = function (this: any) {
    originalDisconnectedCallback?.call(this);
    if (this.__disconnectedCallbackCalls__) {
      this.__disconnectedCallbackCalls__.forEach(
        (callback: ConnectedCallback) => callback(this)
      );
    }
  };
}