const ROLLING_WINDOW = 50;
const CONSECUTIVE_LIMIT = 3;
const ROLLING_DENIAL_LIMIT = 10;

export class DenialCircuitBreaker {
  private consecutiveDenials = 0;
  private readonly recent: boolean[] = [];
  private tripped = false;

  resetTurn(): void {
    this.consecutiveDenials = 0;
    this.recent.length = 0;
    this.tripped = false;
  }

  recordExplicitDenial(): boolean {
    this.consecutiveDenials += 1;
    this.push(true);
    if (!this.tripped && (this.consecutiveDenials >= CONSECUTIVE_LIMIT || this.denialCount() >= ROLLING_DENIAL_LIMIT)) {
      this.tripped = true;
      return true;
    }
    return false;
  }

  /** Allows and failed-closed outcomes are both non-denials for the Codex-compatible breaker. */
  recordNonDenial(): void {
    this.consecutiveDenials = 0;
    this.push(false);
  }

  isTripped(): boolean {
    return this.tripped;
  }

  private push(denied: boolean): void {
    this.recent.push(denied);
    if (this.recent.length > ROLLING_WINDOW) this.recent.shift();
  }

  private denialCount(): number {
    return this.recent.filter(Boolean).length;
  }
}