/**
 * Commands Hook
 *
 * 管理斜杠命令的加载、搜索和缓存
 */

import { useState, useEffect, useCallback, useRef } from 'react';
import { listCommands, searchCommands } from '../api/client.js';
import type { CommandListResponse } from '../api/types.js';

type CommandItem = CommandListResponse['commands'][number];

interface UseCommandsOptions {
  /** 是否在挂载时自动加载命令列表 */
  autoLoad?: boolean;
}

interface UseCommandsState {
  /** 所有命令列表 */
  commands: CommandItem[];
  /** 过滤后的命令列表 */
  filteredCommands: CommandItem[];
  /** 是否正在加载 */
  isLoading: boolean;
  /** 错误信息 */
  error: string | null;
}

export function useCommands(options: UseCommandsOptions = {}) {
  const { autoLoad = true } = options;

  const [state, setState] = useState<UseCommandsState>({
    commands: [],
    filteredCommands: [],
    isLoading: false,
    error: null,
  });

  const loadedRef = useRef(false);

  // 加载命令列表
  const loadCommands = useCallback(async () => {
    if (state.isLoading) return;

    setState((prev) => ({ ...prev, isLoading: true, error: null }));

    try {
      const result = await listCommands();
      if (result.success) {
        setState({
          commands: result.data.commands,
          filteredCommands: result.data.commands,
          isLoading: false,
          error: null,
        });
      } else {
        setState((prev) => ({
          ...prev,
          isLoading: false,
          error: 'Failed to load commands',
        }));
      }
    } catch (error) {
      setState((prev) => ({
        ...prev,
        isLoading: false,
        error: error instanceof Error ? error.message : 'Unknown error',
      }));
    }
  }, [state.isLoading]);

  // 搜索/过滤命令
  const filterCommands = useCallback(
    async (query: string) => {
      // 空查询显示所有命令
      if (!query.trim()) {
        setState((prev) => ({
          ...prev,
          filteredCommands: prev.commands,
        }));
        return;
      }

      // 本地过滤（快速响应）
      const queryLower = query.toLowerCase();
      const localFiltered = state.commands.filter(
        (cmd) =>
          cmd.name.toLowerCase().includes(queryLower) ||
          cmd.description?.toLowerCase().includes(queryLower)
      );

      // 如果本地过滤有结果，直接使用
      if (localFiltered.length > 0) {
        setState((prev) => ({
          ...prev,
          filteredCommands: localFiltered,
        }));
        return;
      }

      // 否则尝试服务端搜索（可能有模糊匹配）
      try {
        const result = await searchCommands(query, 10);
        if (result.success && result.data.length > 0) {
          setState((prev) => ({
            ...prev,
            filteredCommands: result.data.map((r) => ({
              name: r.name,
              description: r.description,
              source: r.source,
            })),
          }));
        } else {
          setState((prev) => ({
            ...prev,
            filteredCommands: [],
          }));
        }
      } catch {
        // 搜索失败，保持本地过滤结果
        setState((prev) => ({
          ...prev,
          filteredCommands: localFiltered,
        }));
      }
    },
    [state.commands]
  );

  // 自动加载
  useEffect(() => {
    if (autoLoad && !loadedRef.current) {
      loadedRef.current = true;
      loadCommands();
    }
  }, [autoLoad, loadCommands]);

  return {
    ...state,
    loadCommands,
    filterCommands,
  };
}