"use client";

import { useEffect, useState } from "react";

import { CheckCircle2, Package, PackageCheck } from "lucide-react";

import { Sheet, SheetContent } from "@/components/ui/sheet";
import { OrderTicket } from "@/components/order-ticket/order-ticket";
import { StageBadge } from "@/components/order-ticket/stage-badge";
import { type AuthUser, getAuthUser } from "@/lib/auth";
import { useLanguage } from "@/lib/language-context";
import type { Order } from "@/lib/order/types";
import { useOrdersStore } from "@/stores/orders/orders-store";

const PACKING_STAGES = ["ready", "assigned"] as const;

export default function PackagingPage() {
  const [user, setUser] = useState<AuthUser | null>(null);
  const [selectedId, setSelectedId] = useState<string | null>(null);

  const orders = useOrdersStore((s) => s.orders);
  const updateItemStates = useOrdersStore((s) => s.updateItemStates);

  const { lang } = useLanguage();
  useEffect(() => { setUser(getAuthUser()); }, []);

  const packingOrders = orders
    .filter((o) => (PACKING_STAGES as readonly string[]).includes(o.stage))
    .sort((a, b) => {
      if (a.requestedAt && b.requestedAt)
        return new Date(a.requestedAt).getTime() - new Date(b.requestedAt).getTime();
      return new Date(a.orderedAt).getTime() - new Date(b.orderedAt).getTime();
    });

  const selectedOrder = orders.find((o) => o.id === selectedId);

  const allItemsDone = (order: Order) =>
    order.items.every((item) => order.itemStates?.[item.code] === "done");

  const toggleItem = (order: Order, code: string) => {
    const current = order.itemStates?.[code];
    const updated = { ...(order.itemStates ?? {}) };
    if (current === "done") delete updated[code];
    else updated[code] = "done";
    updateItemStates(order.id, updated);
  };

  return (
    <div className="flex h-full flex-col gap-4">
      <div className="flex items-center justify-between">
        <div>
          <h1 className="font-bold text-xl">Packaging</h1>
          <p className="text-muted-foreground text-sm">{packingOrders.length} orders to pack</p>
        </div>
        <Package className="size-6 text-muted-foreground" />
      </div>

      {packingOrders.length === 0 && (
        <div className="flex flex-1 flex-col items-center justify-center gap-2 text-muted-foreground">
          <PackageCheck className="size-12 opacity-20" />
          <p className="text-sm">No orders ready to pack</p>
        </div>
      )}

      <div className="grid gap-3 md:grid-cols-2 lg:grid-cols-3">
        {packingOrders.map((order) => {
          const done = allItemsDone(order);
          return (
            <div
              key={order.id}
              className={`rounded-xl border bg-card transition-all ${done ? "border-green-400 dark:border-green-600" : "border-border"}`}
            >
              {/* Card header */}
              <button
                type="button"
                onClick={() => setSelectedId(order.id)}
                className="flex w-full items-center justify-between px-3 py-2.5 text-left"
              >
                <div className="flex items-center gap-2">
                  <span className="font-mono font-bold text-xs">{order.id}</span>
                  <span className={`rounded border px-1 text-[9px] font-medium ${
                    order.type === "delivery"
                      ? "border-blue-200 bg-blue-500/10 text-blue-700 dark:text-blue-400"
                      : "border-green-200 bg-green-500/10 text-green-700 dark:text-green-400"
                  }`}>
                    {order.type}
                  </span>
                </div>
                <div className="flex items-center gap-2">
                  <StageBadge stage={order.stage} type={order.type} />
                  {done && <CheckCircle2 className="size-4 text-green-500" />}
                </div>
              </button>

              <div className="border-t px-3 py-0.5 text-xs text-muted-foreground">
                {order.customer.na}
              </div>

              {/* Item checklist */}
              <div className="divide-y px-3 py-1">
                {order.items.map((item, i) => {
                  const isDone = order.itemStates?.[item.code] === "done";
                  return (
                    <button
                      key={`${item.code}-${i}`}
                      type="button"
                      onClick={() => toggleItem(order, item.code)}
                      className={`flex w-full items-center gap-2 py-2 text-left transition-colors ${isDone ? "opacity-50" : ""}`}
                    >
                      <div className={`flex size-5 shrink-0 items-center justify-center rounded border-2 transition-colors ${
                        isDone ? "border-green-500 bg-green-500" : "border-muted-foreground/30"
                      }`}>
                        {isDone && <CheckCircle2 className="size-3 text-white" />}
                      </div>
                      <span className={`flex-1 font-bold text-sm ${isDone ? "line-through text-muted-foreground" : ""}`}>
                        {lang === "zh" ? item.chineseName : item.description}
                      </span>
                      <span className="text-muted-foreground text-sm">×{item.qty}</span>
                      {item.notes && (
                        <span className="text-[11px] text-amber-600">{item.notes}</span>
                      )}
                    </button>
                  );
                })}
              </div>
            </div>
          );
        })}
      </div>

      <Sheet open={!!selectedOrder} onOpenChange={(open) => { if (!open) setSelectedId(null); }}>
        <SheetContent side="right" className="w-full w-[440px] max-w-[92vw] p-0 overflow-hidden flex flex-col">
          {selectedOrder && user && (
            <OrderTicket
              order={selectedOrder}
              role={user.role}
              onNew={() => setSelectedId(null)}
              onClose={() => setSelectedId(null)}
            />
          )}
        </SheetContent>
      </Sheet>
    </div>
  );
}