"use client";

import { useCallback, useEffect, useState } from "react";
import { adminApi, errMessage, type WorkOrder } from "@/lib/admin-api";
import {
  Badge,
  Button,
  Card,
  EmptyState,
  ErrorState,
  LoadingBlock,
  Modal,
  Pagination,
  Select,
  StatCard,
  TableWrap,
  Td,
  TextInput,
  Th,
  formatTime,
  statusTone,
  useToast,
} from "@/components/admin/ui";

const STATUS_OPTIONS = [
  { value: "", label: "全部状态" },
  { value: "待处理", label: "待处理" },
  { value: "处理中", label: "处理中" },
  { value: "待审核", label: "待审核" },
  { value: "已完成", label: "已完成" },
  { value: "已驳回", label: "已驳回" },
];

export function WorkOrdersSection() {
  const toast = useToast();
  const [items, setItems] = useState<WorkOrder[]>([]);
  const [total, setTotal] = useState(0);
  const [totalPages, setTotalPages] = useState(0);
  const [page, setPage] = useState(1);
  const [status, setStatus] = useState("");
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState("");
  const [busyId, setBusyId] = useState<number | null>(null);
  const [reviewing, setReviewing] = useState<WorkOrder | null>(null);

  const load = useCallback(async () => {
    setLoading(true);
    setError("");
    try {
      const result = await adminApi.workOrders({ status: status || undefined, page, page_size: 10 });
      setItems(result.items ?? []);
      setTotal(result.total ?? 0);
      setTotalPages(result.total_pages ?? 0);
    } catch (e) {
      setError(errMessage(e, "工单列表加载失败"));
    } finally {
      setLoading(false);
    }
  }, [status, page]);

  useEffect(() => {
    void load();
  }, [load]);

  async function run(id: number, task: () => Promise<unknown>, message: string) {
    setBusyId(id);
    try {
      await task();
      toast(message);
      await load();
    } catch (e) {
      toast(errMessage(e, "操作失败"), "error");
    } finally {
      setBusyId(null);
    }
  }

  const pending = items.filter((item) => item.status === "待处理").length;
  const reviewingCount = items.filter((item) => item.status === "待审核").length;

  return (
    <>
      <div className="grid gap-4 md:grid-cols-3">
        <StatCard label="工单总数" value={total} hint={status ? `筛选：${status}` : "全部状态"} />
        <StatCard label="本页待认领" value={pending} hint="待处理状态" />
        <StatCard
          label="本页待复核"
          value={reviewingCount}
          hint={reviewingCount > 0 ? "等待复核结论" : "暂无待复核工单"}
        />
      </div>

      <Card
        title="工单处理"
        description="认领 → 提交审核 → 复核，状态由后端流转控制"
        bodyClassName="p-0"
        className="mt-6"
        actions={
          <Select value={status} onChange={(event) => { setStatus(event.target.value); setPage(1); }}>
            {STATUS_OPTIONS.map((option) => (
              <option key={option.value} value={option.value}>
                {option.label}
              </option>
            ))}
          </Select>
        }
      >
        {loading ? (
          <LoadingBlock />
        ) : error ? (
          <ErrorState message={error} onRetry={() => void load()} />
        ) : items.length === 0 ? (
          <EmptyState text="没有符合条件的工单" />
        ) : (
          <>
            <TableWrap>
              <thead>
                <tr>
                  <Th>工单号</Th>
                  <Th>类型</Th>
                  <Th>客户</Th>
                  <Th>当前节点</Th>
                  <Th>优先级</Th>
                  <Th>状态</Th>
                  <Th>创建时间</Th>
                  <Th className="text-right">操作</Th>
                </tr>
              </thead>
              <tbody className="divide-y divide-slate-50">
                {items.map((order) => (
                  <tr key={order.id} className="transition-colors hover:bg-slate-50">
                    <Td className="font-medium text-slate-900">{order.work_order_no}</Td>
                    <Td>
                      {order.order_type}
                      {order.sub_type && <span className="text-xs text-slate-400"> · {order.sub_type}</span>}
                    </Td>
                    <Td className="text-slate-500">#{order.customer_id ?? "--"}</Td>
                    <Td>{order.current_node ?? "--"}</Td>
                    <Td>
                      <Badge
                        tone={
                          order.priority === "特急" ? "danger" : order.priority === "紧急" ? "warning" : "neutral"
                        }
                      >
                        {order.priority}
                      </Badge>
                    </Td>
                    <Td>
                      <Badge tone={statusTone(order.status)}>{order.status}</Badge>
                    </Td>
                    <Td className="text-xs text-slate-500">{formatTime(order.create_time)}</Td>
                    <Td>
                      <div className="flex justify-end gap-2">
                        {order.status === "待处理" && (
                          <Button
                            size="sm"
                            variant="primary"
                            loading={busyId === order.id}
                            onClick={() => void run(order.id, () => adminApi.claimWorkOrder(order.id), "工单已认领")}
                          >
                            认领
                          </Button>
                        )}
                        {order.status === "处理中" && (
                          <Button
                            size="sm"
                            variant="primary"
                            loading={busyId === order.id}
                            onClick={() =>
                              void run(order.id, () => adminApi.submitWorkOrder(order.id), "已提交审核")
                            }
                          >
                            提交审核
                          </Button>
                        )}
                        {order.status === "待审核" && (
                          <Button size="sm" variant="primary" onClick={() => setReviewing(order)}>
                            复核
                          </Button>
                        )}
                        {(order.status === "已完成" || order.status === "已驳回") && (
                          <span className="text-xs text-slate-400">已归档</span>
                        )}
                      </div>
                    </Td>
                  </tr>
                ))}
              </tbody>
            </TableWrap>
            <Pagination page={page} totalPages={totalPages} total={total} onChange={setPage} />
          </>
        )}
      </Card>

      {reviewing && (
        <ReviewModal
          order={reviewing}
          onClose={() => setReviewing(null)}
          onDone={async (approve, comment) => {
            await run(
              reviewing.id,
              () => adminApi.reviewWorkOrder(reviewing.id, approve, comment),
              approve ? "复核通过" : "已驳回"
            );
            setReviewing(null);
          }}
        />
      )}
    </>
  );
}

function ReviewModal({
  order,
  onClose,
  onDone,
}: {
  order: WorkOrder;
  onClose: () => void;
  onDone: (approve: boolean, comment: string) => Promise<void>;
}) {
  const [comment, setComment] = useState("");
  const [submitting, setSubmitting] = useState(false);

  async function submit(approve: boolean) {
    setSubmitting(true);
    try {
      await onDone(approve, comment);
    } finally {
      setSubmitting(false);
    }
  }

  return (
    <Modal
      open
      title={`复核工单 ${order.work_order_no}`}
      onClose={onClose}
      footer={
        <>
          <Button onClick={onClose} disabled={submitting}>
            取消
          </Button>
          <Button variant="danger" loading={submitting} onClick={() => void submit(false)}>
            驳回
          </Button>
          <Button variant="primary" loading={submitting} onClick={() => void submit(true)}>
            通过
          </Button>
        </>
      }
    >
      <div className="space-y-4">
        <div className="rounded-lg bg-slate-50 p-3 text-xs text-slate-600">
          <p>工单类型：{order.order_type}</p>
          <p>关联客户：#{order.customer_id ?? "--"}</p>
          <p>优先级：{order.priority}</p>
          <p>当前节点：{order.current_node ?? "--"}</p>
        </div>
        {order.biz_content && (
          <div className="rounded-lg border border-slate-200 p-3 text-xs text-slate-600">
            <p className="mb-1 font-medium text-slate-500">业务内容</p>
            <pre className="whitespace-pre-wrap break-all text-[11px] leading-5 text-slate-500">
              {JSON.stringify(order.biz_content, null, 2)}
            </pre>
          </div>
        )}
        <div>
          <label className="mb-1 block text-xs text-slate-500">复核意见（可选）</label>
          <TextInput
            value={comment}
            onChange={(event) => setComment(event.target.value)}
            placeholder="填写复核说明"
          />
        </div>
        {order.handler_id !== null && (
          <p className="text-xs text-amber-600">提示：若复核人与处理人为同一人，系统仅提示不阻断。</p>
        )}
      </div>
    </Modal>
  );
}