import { useState, useCallback } from 'react';
import type { ChatMessage, SuggestedQuestion } from '../types';

export function useChatMessages(initial: ChatMessage[] = []) {
  const [messages, setMessages] = useState<ChatMessage[]>(initial);

  const addMessage = useCallback((msg: ChatMessage) => {
    setMessages(prev => [...prev, msg]);
  }, []);

  const updateMessage = useCallback(
    (id: string, updates: Partial<ChatMessage> | ((prev: ChatMessage) => Partial<ChatMessage>)) => {
      setMessages(prev =>
        prev.map(m => {
          if (m.id !== id) return m;
          const patch = typeof updates === 'function' ? updates(m) : updates;
          return { ...m, ...patch };
        }),
      );
    },
    [],
  );

  const appendSuggestedQuestions = useCallback(
    (id: string, questions: SuggestedQuestion[]) => {
      setMessages(prev =>
        prev.map(m => (m.id === id ? { ...m, suggestedQuestions: questions } : m)),
      );
    },
    [],
  );

  const clearMessages = useCallback(() => setMessages([]), []);

  return { messages, addMessage, updateMessage, appendSuggestedQuestions, clearMessages };
}