import { useChatSession } from './useChatSession';

export type SlashCommandResult = { handled: true; feedback: string } | { handled: false };

type UseSlashCommandsParams = {
  sessionId: string | null;
};

export function useSlashCommands({ sessionId }: UseSlashCommandsParams) {
  const { rename } = useChatSession({ sessionId });

  const execute = async (input: string): Promise<SlashCommandResult> => {
    const trimmed = input.trim();
    if (!trimmed.startsWith('/')) return { handled: false };
    if (!sessionId) return { handled: false };

    const spaceIndex = trimmed.indexOf(' ');
    const commandName = spaceIndex === -1 ? trimmed.slice(1) : trimmed.slice(1, spaceIndex);
    const args = spaceIndex === -1 ? '' : trimmed.slice(spaceIndex + 1).trim();

    try {
      switch (commandName) {
        case 'rename': {
          if (!args.trim()) {
            return { handled: true, feedback: 'Usage: /rename <new name>' };
          }
          await rename(args);
          return { handled: true, feedback: `Session renamed to "${args}"` };
        }

        case 'help': {
          const helpText = [
            'Available commands:',
            '  /rename <name> - Rename the current session',
            '  /help - Show this help message',
          ].join('\n');
          return { handled: true, feedback: helpText };
        }

        default:
          return { handled: false };
      }
    } catch (error) {
      return { handled: true, feedback: `Error: ${error instanceof Error ? error.message : 'Unknown error'}` };
    }
  };

  return { execute };
}