"use client";

import { useState, useEffect, useCallback } from "react";
import { useAuth } from "@/lib/AuthContext";
import { useRouter } from "next/navigation";
import {
  ShoppingBag,
  Package,
  User,
  Clock,
  ChevronRight,
  Loader2,
  Inbox,
} from "lucide-react";
import ErrorFeedback from "@/components/ErrorFeedback";

// ── Types ──
interface OrderListing {
  id: string;
  title: string;
  category: string;
  priceFlh: number;
}

interface OrderParty {
  id: string;
  name: string;
  email: string;
  avatar?: string | null;
}

interface Order {
  id: string;
  listingId: string;
  buyerId: string;
  sellerId: string;
  status: string;
  amountFlh: number;
  platformFee: number;
  packageName?: string | null;
  createdAt: string;
  listing: OrderListing;
  buyer: OrderParty;
  seller: OrderParty;
}

// ── Status helpers ──
const STATUS_COLORS: Record<string, { bg: string; text: string; label: string }> = {
  pending: { bg: "bg-gray-800/60", text: "text-gray-400", label: "Pending" },
  paid: { bg: "bg-blue-900/20 border border-blue-700/30", text: "text-blue-400", label: "Paid" },
  in_progress: { bg: "bg-amber-900/20 border border-amber-700/30", text: "text-amber-400", label: "In Progress" },
  delivered: { bg: "bg-purple-900/20 border border-purple-700/30", text: "text-purple-400", label: "Delivered" },
  completed: { bg: "bg-emerald-900/20 border border-emerald-700/30", text: "text-emerald-400", label: "Completed" },
  disputed: { bg: "bg-red-900/20 border border-red-700/30", text: "text-red-400", label: "Disputed" },
  cancelled: { bg: "bg-gray-800/40 border border-gray-700/30", text: "text-gray-500", label: "Cancelled" },
};

function getStatusStyle(status: string) {
  return STATUS_COLORS[status] || STATUS_COLORS.pending;
}

function formatDate(dateStr: string) {
  const d = new Date(dateStr);
  return d.toLocaleDateString("en-MY", {
    year: "numeric",
    month: "short",
    day: "numeric",
  });
}

function timeAgo(dateStr: string): string {
  const now = Date.now();
  const then = new Date(dateStr).getTime();
  const diffSec = Math.floor((now - then) / 1000);
  if (diffSec < 60) return "just now";
  const diffMin = Math.floor(diffSec / 60);
  if (diffMin < 60) return `${diffMin}m ago`;
  const diffHr = Math.floor(diffMin / 60);
  if (diffHr < 24) return `${diffHr}h ago`;
  const diffDay = Math.floor(diffHr / 24);
  if (diffDay < 7) return `${diffDay}d ago`;
  return formatDate(dateStr);
}

export default function OrdersPage() {
  const { user, token, loading } = useAuth();
  const router = useRouter();

  const [tab, setTab] = useState<"buyer" | "seller">("buyer");
  const [orders, setOrders] = useState<Order[]>([]);
  const [loadingOrders, setLoadingOrders] = useState(true);
  const [error, setError] = useState<string | null>(null);

  // ── Auth redirect ──
  useEffect(() => {
    if (!loading && !token) {
      router.push("/auth");
    }
  }, [loading, token, router]);

  // ── Fetch orders ──
  const fetchOrders = useCallback(async () => {
    if (!token) return;
    setLoadingOrders(true);
    setError(null);
    try {
      const res = await fetch(`/mobile/api/souq/orders?role=${tab}&limit=50`, {
        headers: { Authorization: `Bearer ${token}` },
      });
      const data = await res.json();
      if (res.ok) {
        setOrders(data.orders || []);
      } else {
        setError(data.error || "Failed to load orders");
      }
    } catch {
      setError("Network error. Please try again.");
    } finally {
      setLoadingOrders(false);
    }
  }, [token, tab]);

  useEffect(() => {
    if (token) fetchOrders();
  }, [token, fetchOrders]);

  // ── Loading (auth) ──
  if (loading) {
    return (
      <div className="min-h-dvh bg-[#0a0a0f] flex items-center justify-center">
        <div className="w-8 h-8 rounded-full border-2 border-[#D4AF37]/30 border-t-[#D4AF37] animate-spin" />
      </div>
    );
  }

  if (!user) return null;

  return (
    <div className="min-h-dvh bg-[#0a0a0f] pb-24">
      {/* Header */}
      <div className="px-4 pt-6 pb-2">
        <h1 className="text-xl font-bold text-white">My Orders</h1>
      </div>

      {/* Tabs */}
      <div className="px-4 pb-4">
        <div className="flex bg-[#111118] border border-gray-800/60 rounded-xl p-1">
          <button
            onClick={() => setTab("buyer")}
            className={`flex-1 flex items-center justify-center gap-2 py-3 rounded-lg text-sm font-medium transition ${
              tab === "buyer"
                ? "bg-[#D4AF37] text-[#0a0a0f]"
                : "text-gray-500 active:text-gray-300"
            }`}
          >
            <ShoppingBag size={14} />
            As Buyer
          </button>
          <button
            onClick={() => setTab("seller")}
            className={`flex-1 flex items-center justify-center gap-2 py-3 rounded-lg text-sm font-medium transition ${
              tab === "seller"
                ? "bg-[#D4AF37] text-[#0a0a0f]"
                : "text-gray-500 active:text-gray-300"
            }`}
          >
            <Package size={14} />
            As Seller
          </button>
        </div>
      </div>

      {/* Content */}
      <div className="px-4 space-y-3">
        {loadingOrders ? (
          <div className="flex flex-col items-center justify-center py-20">
            <Loader2 size={32} className="text-[#D4AF37] animate-spin mb-3" />
            <p className="text-sm text-gray-500">Loading orders...</p>
          </div>
        ) : error ? (
          <ErrorFeedback error={error} kind="network" onRetry={fetchOrders} context="orders" />
        ) : orders.length === 0 ? (
          <div className="bg-[#111118] border border-gray-800/60 rounded-2xl p-8 text-center">
            <div className="w-14 h-14 rounded-2xl bg-gray-800/40 flex items-center justify-center mx-auto mb-4">
              <Inbox size={28} className="text-gray-600" />
            </div>
            <h3 className="text-base font-semibold text-white mb-1">
              No orders yet
            </h3>
            <p className="text-sm text-gray-500 max-w-xs mx-auto">
              {tab === "buyer"
                ? "You haven't placed any orders yet. Browse the marketplace to get started."
                : "No one has ordered from you yet. List your services to start selling."}
            </p>
            <button
              onClick={() => router.push("/souq")}
              className="mt-4 inline-flex items-center gap-1.5 bg-[#D4AF37]/15 border border-[#D4AF37]/30 rounded-xl px-4 py-3 text-xs font-medium text-[#D4AF37] active:bg-[#D4AF37]/25 transition"
            >
              <ShoppingBag size={12} />
              {tab === "buyer" ? "Browse Marketplace" : "Manage Listings"}
            </button>
          </div>
        ) : (
          orders.map((order) => {
            const sc = getStatusStyle(order.status);
            return (
              <button
                key={order.id}
                onClick={() => router.push(`/souq/orders/${order.id}`)}
                className="w-full text-left bg-[#111118] border border-gray-800/60 rounded-2xl p-4 active:bg-[#1a1a24] transition animate-fade-in"
              >
                {/* Listing title + status */}
                <div className="flex items-start justify-between gap-3 mb-2">
                  <h3 className="text-sm font-semibold text-white leading-tight line-clamp-2 flex-1">
                    {order.listing.title}
                  </h3>
                  <span
                    className={`shrink-0 text-[10px] font-medium px-2.5 py-1 rounded-full ${sc.bg} ${sc.text}`}
                  >
                    {sc.label}
                  </span>
                </div>

                {/* Buyer/Seller + Amount */}
                <div className="flex items-center justify-between gap-2">
                  <div className="flex items-center gap-1.5 min-w-0">
                    <User size={11} className="text-gray-600 shrink-0" />
                    <span className="text-xs text-gray-400 truncate">
                      {tab === "buyer" ? order.seller.name : order.buyer.name}
                    </span>
                  </div>
                  <div className="flex items-center gap-2 shrink-0">
                    <span className="text-sm font-bold text-[#D4AF37]">
                      {order.amountFlh.toLocaleString()} FLH
                    </span>
                    <ChevronRight size={14} className="text-gray-600" />
                  </div>
                </div>

                {/* Date */}
                <div className="flex items-center gap-1 mt-1.5">
                  <Clock size={10} className="text-gray-600" />
                  <span className="text-[10px] text-gray-600">
                    {timeAgo(order.createdAt)}
                  </span>
                </div>
              </button>
            );
          })
        )}
      </div>
    </div>
  );
}