"use client";

// Client-side order ledger. Every buy path writes here; every monitoring surface
// reads it merged with /api/orders. This makes buy → monitor work in the browser
// before the database is provisioned; once POSTGRES_URL is set the API is the
// source of truth and this becomes a local cache.
export interface LocalOrder {
  order_id: string;
  flow: string;
  status: string;
  total_ore: number;
  deposit_ore: number;
  balance_ore: number;
  config?: Record<string, unknown>;
  created_at: string;
}

const KEY = "0pt-orders";

export function getLocalOrders(): LocalOrder[] {
  if (typeof window === "undefined") return [];
  try { return JSON.parse(localStorage.getItem(KEY) || "[]"); } catch { return []; }
}

export function saveLocalOrder(o: LocalOrder): void {
  if (typeof window === "undefined") return;
  const all = getLocalOrders().filter((x) => x.order_id !== o.order_id);
  all.unshift(o);
  localStorage.setItem(KEY, JSON.stringify(all.slice(0, 200)));
}

export function getLocalOrder(id: string): LocalOrder | null {
  return getLocalOrders().find((o) => o.order_id === id) ?? null;
}

export function setLocalStatus(id: string, status: string): void {
  if (typeof window === "undefined") return;
  const all = getLocalOrders();
  const o = all.find((x) => x.order_id === id);
  if (o) { o.status = status; localStorage.setItem(KEY, JSON.stringify(all)); }
}

/** Merge server orders with local ones (server wins on conflict). */
export function mergeOrders<T extends { order_id: string }>(server: T[]): (T | LocalOrder)[] {
  const ids = new Set(server.map((s) => s.order_id));
  return [...server, ...getLocalOrders().filter((l) => !ids.has(l.order_id))];
}

/** Create an order via the API and record it locally. Returns the id (or null). */
export async function createOrder(flow: string, config: Record<string, unknown>): Promise<string | null> {
  try {
    const res = await fetch("/api/orders", {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ flow, config }),
    });
    const o = await res.json();
    if (o?.order_id) {
      const total = o.total_ore ?? 0;
      const deposit = o.deposit_ore ?? Math.round(total / 2);
      saveLocalOrder({
        order_id: o.order_id, flow, status: "draft",
        total_ore: total, deposit_ore: deposit, balance_ore: total - deposit,
        config, created_at: new Date().toISOString(),
      });
      return o.order_id;
    }
  } catch {}
  return null;
}