/**
 * System Commands Hook
 *
 * 管理系统命令（: 前缀）的加载和过滤
 */

import { useState, useEffect, useCallback, useRef } from 'react';
import { listSystemCommands } from '../api/client.js';
import type { SystemCommandInfo } from '../api/types.js';

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

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

export function useSystemCommands(options: UseSystemCommandsOptions = {}) {
  const { autoLoad = true } = options;

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

  const loadedRef = useRef(false);

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

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

    try {
      const result = await listSystemCommands();
      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 system commands',
        }));
      }
    } catch (error) {
      setState((prev) => ({
        ...prev,
        isLoading: false,
        error: error instanceof Error ? error.message : 'Unknown error',
      }));
    }
  }, [state.isLoading]);

  // 搜索/过滤系统命令
  const filterCommands = useCallback(
    (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
      const queryLower = query.toLowerCase();
      const localFiltered = state.commands.filter(
        (cmd) =>
          cmd.name.toLowerCase().includes(queryLower) ||
          cmd.description?.toLowerCase().includes(queryLower) ||
          cmd.aliases?.some((alias) => alias.toLowerCase().includes(queryLower))
      );

      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,
  };
}