"use client";

import { useState } from "react";
import { useRouter } from "next/navigation";
import Link from "next/link";
import { Heart, MessageCircle, CheckCheck, Bell, CheckCircle2, XCircle } from "lucide-react";
import { apiMarkRead, apiMarkAllRead, type NotificationsResponse, type NotificationItem } from "@/lib/api";

/**
 * 通知列表交互层：数据由服务端 SSR 直出，这里只承担已读标记等客户端操作。
 */
export default function NotificationsClient({ initialData }: { initialData: NotificationsResponse }) {
  const router = useRouter();
  const [notifications, setNotifications] = useState<NotificationItem[]>(initialData.notifications || []);

  const handleClick = async (n: NotificationItem) => {
    if (!n.is_read) {
      apiMarkRead(n.id).catch(() => {});
      setNotifications((list) =>
        list.map((item) => (item.id === n.id ? { ...item, is_read: true } : item))
      );
    }
    router.push(`/post/${n.post_id}`);
  };

  const handleMarkAll = async () => {
    await apiMarkAllRead();
    setNotifications((list) => list.map((item) => ({ ...item, is_read: true })));
    // 同步刷新 Header 未读红点（layout 重新取 unread_count）
    router.refresh();
  };

  const formatTime = (dateStr: string) => {
    const diff = Date.now() - new Date(dateStr).getTime();
    const min = Math.floor(diff / 60000);
    if (min < 1) return "刚刚";
    if (min < 60) return `${min} 分钟前`;
    const hour = Math.floor(min / 60);
    if (hour < 24) return `${hour} 小时前`;
    return `${Math.floor(hour / 24)} 天前`;
  };

  const hasUnread = notifications.some((n) => !n.is_read);

  return (
    <>
      {hasUnread && (
        <div className="flex justify-end mb-4">
          <button onClick={handleMarkAll} className="btn btn-line btn-sm">
            <CheckCheck size={14} /> 全部已读
          </button>
        </div>
      )}

      {notifications.length === 0 ? (
        <div className="panel text-center py-20 px-6">
          <span
            className="inline-flex w-14 h-14 rounded-full items-center justify-center mb-4"
            style={{ background: "var(--accent-soft)", color: "var(--accent)" }}
          >
            <Bell size={26} />
          </span>
          <p className="font-bold text-lg" style={{ color: "var(--ink)" }}>还没有通知</p>
          <p className="meta mt-1.5">当有人评论或点赞你的帖子时，会在这里提醒你</p>
        </div>
      ) : (
        <div className="panel overflow-hidden p-0">
          {notifications.map((n, i) => {
            const approval = n.type === "approved" || n.type === "rejected";
            const iconNode = n.type === "approved"
              ? <CheckCircle2 size={16} />
              : n.type === "rejected"
                ? <XCircle size={16} />
                : n.type === "like"
                  ? <Heart size={16} />
                  : <MessageCircle size={16} />;
            const iconColor = n.type === "approved"
              ? "var(--ok)"
              : n.type === "rejected"
                ? "var(--danger)"
                : n.type === "like"
                  ? "var(--clay)"
                  : "var(--accent)";
            const iconBg = n.type === "approved"
              ? "var(--ok-soft)"
              : n.type === "rejected"
                ? "var(--danger-soft)"
                : n.type === "like"
                  ? "var(--clay-soft)"
                  : "var(--accent-soft)";
            return (
            <button
              key={n.id}
              onClick={() => handleClick(n)}
              className={`w-full text-left px-4 sm:px-5 py-4 flex items-start gap-3.5 transition-colors hover:bg-[var(--accent-soft)] focus-visible:bg-[var(--accent-soft)] ${
                n.is_read ? "" : "bg-[var(--panel-2)]"
              }`}
              style={{
                borderTop: i === 0 ? "none" : "1px solid var(--line)",
              }}
            >
              <span
                className="w-10 h-10 shrink-0 rounded-full flex items-center justify-center"
                style={{ color: iconColor, background: iconBg }}
              >
                {iconNode}
              </span>
              <div className="flex-1 min-w-0">
                <p className="text-sm leading-snug" style={{ color: "var(--ink)" }}>
                  {approval ? (
                    <span
                      className="font-bold"
                      style={{ color: n.type === "approved" ? "var(--ok)" : "var(--danger)" }}
                    >
                      {n.type === "approved" ? "审核通过" : "未通过审核"}
                    </span>
                  ) : (
                    <>
                      <Link
                        href={`/u/${n.actor.id}`}
                        onClick={(e) => e.stopPropagation()}
                        className="font-semibold hover:text-[var(--accent)] transition-colors"
                      >
                        {n.actor.nickname}
                      </Link>{" "}
                      <span className="meta">
                        {n.type === "comment"
                          ? "评论了你的帖子"
                          : n.type === "reply"
                            ? "回复了你的评论"
                            : "点赞了你的帖子"}
                      </span>
                    </>
                  )}
                </p>
                <p className="text-sm mt-1 truncate" style={{ color: "var(--ink-2)" }}>
                  《{n.post.title}》
                </p>
                {n.content && (
                  <p className="text-[13px] mt-1.5 line-clamp-2" style={{ color: "var(--ink-3)" }}>
                    {n.content}
                  </p>
                )}
                <p className="meta text-xs mt-2">{formatTime(n.created_at)}</p>
              </div>
              {!n.is_read && (
                <span className="w-2.5 h-2.5 shrink-0 mt-2 rounded-full" style={{ background: "var(--clay)" }} />
              )}
            </button>
            );
          })}
        </div>
      )}
    </>
  );
}