import { API_BASE, SITE_DOMAIN } from "./config";
import type { StoreLoanCalculateResponse, StoreLoanMethodsResponse } from "./types";

const base = `${API_BASE}/tenants/${SITE_DOMAIN}/store-loan-methods`;

/** Browser-side list — same contract as GET .../store-loan-methods. */
export async function fetchStoreLoanMethods(
  signal?: AbortSignal,
): Promise<StoreLoanMethodsResponse> {
  const res = await fetch(base, { signal });
  if (!res.ok) throw new Error(`loan methods failed (${res.status})`);
  return res.json() as Promise<StoreLoanMethodsResponse>;
}

/** Browser-side calculate — POST .../store-loan-methods/calculate. */
export async function fetchStoreLoanPlan(
  input: {
    methodId: string;
    totalValue: number;
    creditAmount: number;
    months: number;
  },
  signal?: AbortSignal,
): Promise<StoreLoanCalculateResponse> {
  const res = await fetch(`${base}/calculate`, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify(input),
    signal,
  });
  if (!res.ok) {
    let message = `calculate failed (${res.status})`;
    try {
      const body = (await res.json()) as { message?: string };
      if (body.message) message = body.message;
    } catch {
      /* ignore */
    }
    throw new Error(message);
  }
  return res.json() as Promise<StoreLoanCalculateResponse>;
}

export function clampCreditAmount(
  value: number,
  totalValue: number,
  minAmount: number,
  maxAmount: number,
): number {
  const upper = Math.min(Math.round(maxAmount), Math.round(totalValue));
  const lower = Math.min(Math.round(minAmount), upper);
  return Math.min(upper, Math.max(lower, Math.round(value)));
}