export function getHex64(json: string, field: string): string {
  let len = field.length + 3;
  let idx = json.indexOf(`"${field}":`) + len;
  let s = json.slice(idx).indexOf(`"`) + idx + 1;
  return json.slice(s, s + 64);
}

export function getSubName(json: string): string {
  let idx = json.indexOf(`"EVENT"`) + 7;
  let sliced = json.slice(idx);
  let idx2 = sliced.indexOf(`"`) + 1;
  let sliced2 = sliced.slice(idx2);
  return sliced2.slice(0, sliced2.indexOf(`"`));
}

export function getInt(json: string, field: string): number {
  let len = field.length;
  let idx = json.indexOf(`"${field}":`) + len + 3;
  let sliced = json.slice(idx);
  let end = Math.min(sliced.indexOf(","), sliced.indexOf("}"));
  return parseInt(sliced.slice(0, end), 10);
}

export function matchEventId(json: string, id: string): boolean {
  return id === getHex64(json, "id");
}

export function matchEventPubkey(json: string, pubkey: string): boolean {
  return pubkey === getHex64(json, "pubkey");
}

export function matchEventKind(json: string, kind: number): boolean {
  return kind === getInt(json, "kind");
}