import { useState } from "react";
import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import { toast } from "sonner";
import { acknowledgeAnnouncement, fetchAnnouncements, type AnnouncementAcknowledgementStatus, type PortalAnnouncement } from "../api/announcements";
import { PageHeader } from "../components/common/PageHeader";
import { Button } from "../components/ui/button";
import { formatDisplayDate, formatDisplayDateTime } from "../lib/displayFormat";

function acknowledgementLabel(status: AnnouncementAcknowledgementStatus) {
  if (status === "acknowledged") return "已签收";
  if (status === "overdue") return "已逾期";
  if (status === "pending") return "待签收";
  return "普通公告";
}

function acknowledgementBadgeClass(status: AnnouncementAcknowledgementStatus) {
  if (status === "acknowledged") return "badge-success";
  if (status === "overdue") return "badge-error";
  if (status === "pending") return "badge-warning";
  return "badge-neutral";
}

function AnnouncementCard({
  item,
  checked,
  submitting,
  onCheckedChange,
  onAcknowledge,
}: {
  item: PortalAnnouncement;
  checked: boolean;
  submitting: boolean;
  onCheckedChange: (checked: boolean) => void;
  onAcknowledge: () => void;
}) {
  const acknowledgement = item.acknowledgement ?? { status: "not_required", acknowledgedAt: null, overdue: false };
  const requiresAcknowledgement = item.requiresAcknowledgement;
  const isAcknowledged = acknowledgement.status === "acknowledged";
  const canSubmit = requiresAcknowledgement && !isAcknowledged && checked && !submitting;

  return (
    <article
      className={`card-std p-5 md:p-6 ${requiresAcknowledgement ? "border-l-4 border-l-[var(--color-accent-primary)]" : ""}`}
      data-testid={`announcement-card-${item.id}`}
    >
      <div className="flex flex-col gap-3 md:flex-row md:items-start md:justify-between">
        <div className="min-w-0">
          <div className="flex flex-wrap items-center gap-2">
            <h2 className="text-lg font-semibold leading-7 text-zinc-900">{item.title}</h2>
            <span className={acknowledgementBadgeClass(acknowledgement.status)}>
              {acknowledgementLabel(acknowledgement.status)}
            </span>
          </div>
          <p className="mt-2 text-sm leading-6 text-zinc-600">{item.summary}</p>
        </div>
        {item.acknowledgementDueAt ? (
          <div className="shrink-0 rounded-lg border border-slate-200 bg-slate-50 px-3 py-2 text-xs text-zinc-600">
            截止：{formatDisplayDate(item.acknowledgementDueAt)}
          </div>
        ) : null}
      </div>

      {item.linkUrl ? (
        <a className="mt-3 inline-flex text-sm font-medium text-primary hover:underline" href={item.linkUrl} target="_blank" rel="noreferrer">
          查看链接
        </a>
      ) : null}

      {requiresAcknowledgement ? (
        <div className="mt-4 rounded-lg border border-slate-200 bg-slate-50/70 p-4">
          <div className="text-xs font-semibold text-zinc-500">签收声明</div>
          <div className="mt-1 text-sm leading-6 text-zinc-800">{item.acknowledgementStatement}</div>
          {isAcknowledged ? (
            <div className="mt-3 text-sm text-emerald-700">
              已于 {formatDisplayDateTime(acknowledgement.acknowledgedAt)} 完成本人签收。
            </div>
          ) : (
            <div className="mt-4 flex flex-col gap-3 md:flex-row md:items-center md:justify-between">
              <label className="flex min-w-0 items-start gap-2 text-sm leading-6 text-zinc-700">
                <input
                  type="checkbox"
                  className="mt-1 h-4 w-4 rounded border-zinc-300"
                  checked={checked}
                  onChange={(event) => onCheckedChange(event.target.checked)}
                />
                <span>我已阅读并理解该制度内容，确认按公司制度执行。</span>
              </label>
              <Button type="button" className="w-full md:w-auto" disabled={!canSubmit} onClick={onAcknowledge}>
                {submitting ? "提交中..." : acknowledgement.status === "overdue" ? "逾期补签" : "确认签收"}
              </Button>
            </div>
          )}
        </div>
      ) : null}
    </article>
  );
}

export function AnnouncementsPage() {
  const queryClient = useQueryClient();
  const [checkedById, setCheckedById] = useState<Record<string, boolean>>({});
  const announcementsQuery = useQuery({ queryKey: ["announcements", "public"], queryFn: () => fetchAnnouncements(false) });
  const acknowledgeMutation = useMutation({
    mutationFn: acknowledgeAnnouncement,
    onSuccess: async (_data, id) => {
      setCheckedById((current) => ({ ...current, [id]: false }));
      await queryClient.invalidateQueries({ queryKey: ["announcements"] });
      toast.success("签收已记录");
    },
    onError: () => {
      toast.error("签收失败，请刷新后重试");
    },
  });

  return (
    <div className="space-y-6">
      <PageHeader title="公告" subtitle="查看公司通知、制度链接和需要本人确认的制度签收。" />
      <div className="space-y-4">
        {announcementsQuery.isLoading ? <div className="card-std p-6 text-sm text-zinc-500">公告加载中...</div> : null}
        {(announcementsQuery.data?.items ?? []).map((item) => (
          <AnnouncementCard
            key={item.id}
            item={item}
            checked={Boolean(checkedById[item.id])}
            submitting={acknowledgeMutation.isPending && acknowledgeMutation.variables === item.id}
            onCheckedChange={(checked) => setCheckedById((current) => ({ ...current, [item.id]: checked }))}
            onAcknowledge={() => acknowledgeMutation.mutate(item.id)}
          />
        ))}
        {!announcementsQuery.isLoading && !(announcementsQuery.data?.items ?? []).length ? (
          <div className="card-std p-6 text-sm text-zinc-500">暂无公告</div>
        ) : null}
      </div>
    </div>
  );
}

export default AnnouncementsPage;