import { InFlightPaymentStateSchema } from "@aibtc/tx-schemas/core";

// =============================================================================
// Retry Decision Context
// =============================================================================

/**
 * Structured context extracted from a payment error response body.
 * Callers use this to decide whether to retry, reuse, or rebuild a payment.
 */
export interface RetryDecisionContext {
  /** Canonical payment state from relay (e.g. "queued", "failed", "confirmed") */
  status?: string;
  /** Terminal reason if payment failed (e.g. "sender_nonce_stale") */
  terminalReason?: string;
  /** Relay-assigned payment identifier */
  paymentId?: string;
  /** True if the relay indicates the caller should retry */
  retryable?: boolean;
}

/**
 * Extract a RetryDecisionContext from a parsed (unknown) error response body.
 * Returns null if the body has no recognizable retry context fields.
 *
 * Handles the canonical 402 error body shape:
 *   { status, terminalReason, paymentId, retryable, ... }
 */
export function getRetryDecisionContext(body: unknown): RetryDecisionContext | null {
  if (typeof body !== "object" || body === null || Array.isArray(body)) {
    return null;
  }
  const record = body as Record<string, unknown>;

  // Require at least status or paymentId to be present for a meaningful context
  if (typeof record.status !== "string" && typeof record.paymentId !== "string") {
    return null;
  }

  const ctx: RetryDecisionContext = {};
  if (typeof record.status === "string") ctx.status = record.status;
  if (typeof record.terminalReason === "string") ctx.terminalReason = record.terminalReason;
  if (typeof record.paymentId === "string") ctx.paymentId = record.paymentId;
  if (typeof record.retryable === "boolean") ctx.retryable = record.retryable;

  return ctx;
}

export function isInFlightPaymentState(
  status: string | undefined
): status is "queued" | "broadcasting" | "mempool" {
  const parsed = InFlightPaymentStateSchema.safeParse(status);
  return parsed.success;
}

export function isSenderRebuildTerminalReason(reason: string | undefined): boolean {
  return (
    reason === "sender_nonce_stale" ||
    reason === "sender_nonce_gap" ||
    reason === "sender_nonce_duplicate"
  );
}

export function isRelayRetryableTerminalReason(reason: string | undefined): boolean {
  return (
    reason === "queue_unavailable" ||
    reason === "sponsor_failure" ||
    reason === "broadcast_failure" ||
    reason === "chain_abort" ||
    reason === "internal_error"
  );
}