import { useCallback, useMemo, useState } from "react";
import { App, Breadcrumb, Button, Input, Table } from "antd";
import { useNavigate } from "react-router";
import {
  KnowledgeContentType,
  KnowledgeItemSearchResult,
  KnowledgeSourceType,
} from "../knowledge-management.model";
import {
  knowledgeContentTypeOptions,
  knowledgeSourceTypeOptions,
} from "../knowledge-management.const";
import { searchKnowledgeItemsUsingGet } from "../knowledge-management.api";
import { formatBytes, formatDateTime } from "@/utils/unit";

const buildOptionMap = (options: { label: string; value: string }[]) =>
  options.reduce<Record<string, string>>((acc, option) => {
    acc[option.value] = option.label;
    return acc;
  }, {});

export default function KnowledgeManagementSearch() {
  const navigate = useNavigate();
  const { message } = App.useApp();
  const [searchTerm, setSearchTerm] = useState("");
  const [activeKeyword, setActiveKeyword] = useState("");
  const [loading, setLoading] = useState(false);
  const [searched, setSearched] = useState(false);
  const [results, setResults] = useState<KnowledgeItemSearchResult[]>([]);
  const [pagination, setPagination] = useState({
    current: 1,
    pageSize: 10,
    total: 0,
  });

  const contentTypeMap = useMemo(
    () => buildOptionMap(knowledgeContentTypeOptions),
    []
  );
  const sourceTypeMap = useMemo(
    () => buildOptionMap(knowledgeSourceTypeOptions),
    []
  );

  const fetchResults = useCallback(
    async (keyword: string, page?: number, pageSize?: number) => {
      const resolvedPage = page ?? pagination.current;
      const resolvedPageSize = pageSize ?? pagination.pageSize;
      if (!keyword) {
        setResults([]);
        setPagination((prev) => ({ ...prev, total: 0, current: resolvedPage }));
        setSearched(false);
        return;
      }
      setLoading(true);
      try {
        const { data } = await searchKnowledgeItemsUsingGet({
          keyword,
          page: Math.max(resolvedPage - 1, 0),
          size: resolvedPageSize,
        });
        const content = Array.isArray(data?.content) ? data.content : [];
        setResults(content);
        setPagination({
          current: resolvedPage,
          pageSize: resolvedPageSize,
          total: data?.totalElements ?? 0,
        });
        setSearched(true);
      } catch (error) {
        console.error("Failed to search knowledge items:", error);
        message.error("检索失败，请稍后重试");
      } finally {
        setLoading(false);
      }
    },
    [message, pagination]
  );

  const handleSearch = (value?: string) => {
    const keyword = (value ?? searchTerm).trim();
    if (!keyword) {
      message.warning("请输入文件名");
      return;
    }
    setActiveKeyword(keyword);
    fetchResults(keyword, 1, pagination.pageSize);
  };

  const columns = useMemo(
    () => [
      {
        title: "知识集",
        dataIndex: "setName",
        key: "setName",
        width: 220,
        ellipsis: true,
        render: (text: string) => text || "-",
      },
      {
        title: "文件名",
        dataIndex: "fileName",
        key: "fileName",
        width: 220,
        ellipsis: true,
        render: (_: string, record: KnowledgeItemSearchResult) =>
          record.fileName || record.sourceFileId || "-",
      },
      {
        title: "来源类型",
        dataIndex: "sourceType",
        key: "sourceType",
        width: 140,
        render: (value: KnowledgeSourceType) =>
          sourceTypeMap[value] || value || "-",
      },
      {
        title: "内容类型",
        dataIndex: "contentType",
        key: "contentType",
        width: 120,
        render: (value: KnowledgeContentType) =>
          contentTypeMap[value] || value || "-",
      },
      {
        title: "大小",
        dataIndex: "fileSize",
        key: "fileSize",
        width: 120,
        render: (value?: number) => formatBytes(value ?? 0),
      },
      {
        title: "更新时间",
        dataIndex: "updatedAt",
        key: "updatedAt",
        width: 180,
        ellipsis: true,
        render: (value: string) => formatDateTime(value) || "-",
      },
      {
        title: "操作",
        key: "action",
        width: 120,
        align: "right" as const,
        render: (_: unknown, record: KnowledgeItemSearchResult) => (
          <Button
            type="link"
            onClick={() => {
              navigate(`/data/knowledge-management/detail/${record.setId}`);
            }}
          >
            定位
          </Button>
        ),
      },
    ],
    [contentTypeMap, navigate, sourceTypeMap]
  );

  return (
    <div className="h-full flex flex-col gap-4">
      <Breadcrumb>
        <Breadcrumb.Item>
          <a onClick={() => navigate("/data/knowledge-management")}>知识管理</a>
        </Breadcrumb.Item>
        <Breadcrumb.Item>全库搜索</Breadcrumb.Item>
      </Breadcrumb>
      <div className="flex items-center justify-between">
        <h1 className="text-xl font-bold">知识管理全库检索</h1>
      </div>
      <div className="flex items-center gap-3">
        <Input.Search
          allowClear
          value={searchTerm}
          onChange={(event) => setSearchTerm(event.target.value)}
          onSearch={handleSearch}
          placeholder="输入文件名，回车或点击搜索"
          enterButton="搜索"
          loading={loading}
        />
      </div>
      <Table
        rowKey="id"
        loading={loading}
        columns={columns}
        dataSource={results}
        pagination={{
          current: pagination.current,
          pageSize: pagination.pageSize,
          total: pagination.total,
          showTotal: (total) => `共 ${total} 条`,
          onChange: (page, pageSize) => {
            const nextKeyword = activeKeyword.trim();
            if (!nextKeyword) {
              message.warning("请输入文件名");
              return;
            }
            fetchResults(nextKeyword, page, pageSize || pagination.pageSize);
          },
        }}
        locale={{
          emptyText: searched ? "暂无匹配文件" : "请输入文件名开始检索",
        }}
        onRow={(record) => ({
          onClick: () => {
            navigate(`/data/knowledge-management/detail/${record.setId}`);
          },
        })}
      />
    </div>
  );
}