app/components/chat/Chat.client.tsx

/*
 * @ts-nocheck
 * Preventing TS checks with files presented in the video for a better presentation.
 */
import { useStore } from '@nanostores/react';
import type { Message } from 'ai';
import { useChat } from 'ai/react';
import { useAnimate } from 'framer-motion';
import { memo, useCallback, useEffect, useRef, useState } from 'react';
import { cssTransition, toast, ToastContainer } from 'react-toastify';
import { useMessageParser, usePromptEnhancer, useShortcuts, useSnapScroll } from '~/lib/hooks';
import { description, useChatHistory } from '~/lib/persistence';
import { chatStore } from '~/lib/stores/chat';
import { workbenchStore } from '~/lib/stores/workbench';
import { DEFAULT_MODEL, DEFAULT_PROVIDER, PROMPT_COOKIE_KEY, PROVIDER_LIST } from '~/utils/constants';
import { cubicEasingFn } from '~/utils/easings';
import { createScopedLogger, renderLogger } from '~/utils/logger';
import { BaseChat } from './BaseChat';
import Cookies from 'js-cookie';
import type { ProviderInfo } from '~/utils/types';
import { debounce } from '~/utils/debounce';

const toastAnimation = cssTransition({
  enter: 'animated fadeInRight',
  exit: 'animated fadeOutRight',
});

const logger = createScopedLogger('Chat');

export function Chat() {
  renderLogger.trace('Chat');

  const { ready, initialMessages, storeMessageHistory, importChat, exportChat } = useChatHistory();
  const title = useStore(description);

  return (
    <>
      {ready && (
        <ChatImpl
          description={title}
          initialMessages={initialMessages}
          exportChat={exportChat}
          storeMessageHistory={storeMessageHistory}
          importChat={importChat}
        />
      )}
      <ToastContainer
        closeButton={({ closeToast }) => {
          return (
            <button className="Toastify__close-button" onClick={closeToast}>
              <div className="i-ph:x text-lg" />
            </button>
          );
        }}
        icon={({ type }) => {
          /**
           * @todo Handle more types if we need them. This may require extra color palettes.
           */
          switch (type) {
            case 'success': {
              return <div className="i-ph:check-bold text-bolt-elements-icon-success text-2xl" />;
            }
            case 'error': {
              return <div className="i-ph:warning-circle-bold text-bolt-elements-icon-error text-2xl" />;
            }
          }

          return undefined;
        }}
        position="bottom-right"
        pauseOnFocusLoss
        transition={toastAnimation}
      />
    </>
  );
}

interface ChatProps {
  initialMessages: Message[];
  storeMessageHistory: (messages: Message[]) => Promise<void>;
  importChat: (description: string, messages: Message[]) => Promise<void>;
  exportChat: () => void;
  description?: string;
}

export const ChatImpl = memo(
  ({ description, initialMessages, storeMessageHistory, importChat, exportChat }: ChatProps) => {
    useShortcuts();

    const textareaRef = useRef<HTMLTextAreaElement>(null);
    const [chatStarted, setChatStarted] = useState(initialMessages.length > 0);
    const [uploadedFiles, setUploadedFiles] = useState<File[]>([]); // Move here
    const [imageDataList, setImageDataList] = useState<string[]>([]); // Move here

    const [model, setModel] = useState(() => {
      const savedModel = Cookies.get('selectedModel');
      return savedModel || DEFAULT_MODEL;
    });
    const [provider, setProvider] = useState(() => {
      const savedProvider = Cookies.get('selectedProvider');
      return PROVIDER_LIST.find((p) => p.name === savedProvider) || DEFAULT_PROVIDER;
    });

    const { showChat } = useStore(chatStore);

    const [animationScope, animate] = useAnimate();

    const [apiKeys, setApiKeys] = useState<Record<string, string>>({});

    const { messages, isLoading, input, handleInputChange, setInput, stop, append } = useChat({
      api: '/api/chat',
      body: {
        apiKeys,
      },
      onError: (error) => {
        logger.error('Request failed\n\n', error);
        toast.error(
          'There was an error processing your request: ' + (error.message ? error.message : 'No details were returned'),
        );
      },
      onFinish: () => {
        logger.debug('Finished streaming');
      },
      initialMessages,
      initialInput: Cookies.get(PROMPT_COOKIE_KEY) || '',
    });

    const { enhancingPrompt, promptEnhanced, enhancePrompt, resetEnhancer } = usePromptEnhancer();
    const { parsedMessages, parseMessages } = useMessageParser();

    const TEXTAREA_MAX_HEIGHT = chatStarted ? 400 : 200;

    useEffect(() => {
      chatStore.setKey('started', initialMessages.length > 0);
    }, []);

    useEffect(() => {
      parseMessages(messages, isLoading);

      if (messages.length > initialMessages.length) {
        storeMessageHistory(messages).catch((error) => toast.error(error.message));
      }
    }, [messages, isLoading, parseMessages]);

    const scrollTextArea = () => {
      const textarea = textareaRef.current;

      if (textarea) {
        textarea.scrollTop = textarea.scrollHeight;
      }
    };

    const abort = () => {
      stop();
      chatStore.setKey('aborted', true);
      workbenchStore.abortAllActions();
    };

    useEffect(() => {
      const textarea = textareaRef.current;

      if (textarea) {
        textarea.style.height = 'auto';

        const scrollHeight = textarea.scrollHeight;

        textarea.style.height = `${Math.min(scrollHeight, TEXTAREA_MAX_HEIGHT)}px`;
        textarea.style.overflowY = scrollHeight > TEXTAREA_MAX_HEIGHT ? 'auto' : 'hidden';
      }
    }, [input, textareaRef]);

    const runAnimation = async () => {
      if (chatStarted) {
        return;
      }

      await Promise.all([
        animate('#examples', { opacity: 0, display: 'none' }, { duration: 0.1 }),
        animate('#intro', { opacity: 0, flex: 1 }, { duration: 0.2, ease: cubicEasingFn }),
      ]);

      chatStore.setKey('started', true);

      setChatStarted(true);
    };

    const sendMessage = async (_event: React.UIEvent, messageInput?: string) => {
      const _input = messageInput || input;

      if (_input.length === 0 || isLoading) {
        return;
      }

      /**
       * @note (delm) Usually saving files shouldn't take long but it may take longer if there
       * many unsaved files. In that case we need to block user input and show an indicator
       * of some kind so the user is aware that something is happening. But I consider the
       * happy case to be no unsaved files and I would expect users to save their changes
       * before they send another message.
       */
      await workbenchStore.saveAllFiles();

      const fileModifications = workbenchStore.getFileModifcations();

      chatStore.setKey('aborted', false);

      runAnimation();

      if (fileModifications !== undefined) {
        /**
         * If we have file modifications we append a new user message manually since we have to prefix
         * the user input with the file modifications and we don't want the new user input to appear
         * in the prompt. Using `append` is almost the same as `handleSubmit` except that we have to
         * manually reset the input and we'd have to manually pass in file attachments. However, those
         * aren't relevant here.
         */
        append({
          role: 'user',
          content: [
            {
              type: 'text',
              text: `[Model: ${model}]\n\n[Provider: ${provider.name}]\n\n${_input}`,
            },
            ...imageDataList.map((imageData) => ({
              type: 'image',
              image: imageData,
            })),
          ] as any, // Type assertion to bypass compiler check
        });

        /**
         * After sending a new message we reset all modifications since the model
         * should now be aware of all the changes.
         */
        workbenchStore.resetAllFileModifications();
      } else {
        append({
          role: 'user',
          content: [
            {
              type: 'text',
              text: `[Model: ${model}]\n\n[Provider: ${provider.name}]\n\n${_input}`,
            },
            ...imageDataList.map((imageData) => ({
              type: 'image',
              image: imageData,
            })),
          ] as any, // Type assertion to bypass compiler check
        });
      }

      setInput('');
      Cookies.remove(PROMPT_COOKIE_KEY);

      // Add file cleanup here
      setUploadedFiles([]);
      setImageDataList([]);

      resetEnhancer();

      textareaRef.current?.blur();
    };

    /**
     * Handles the change event for the textarea and updates the input state.
     * @param event - The change event from the textarea.
     */
    const onTextareaChange = (event: React.ChangeEvent<HTMLTextAreaElement>) => {
      handleInputChange(event);
    };

    /**
     * Debounced function to cache the prompt in cookies.
     * Caches the trimmed value of the textarea input after a delay to optimize performance.
     */
    const debouncedCachePrompt = useCallback(
      debounce((event: React.ChangeEvent<HTMLTextAreaElement>) => {
        const trimmedValue = event.target.value.trim();
        Cookies.set(PROMPT_COOKIE_KEY, trimmedValue, { expires: 30 });
      }, 1000),
      [],
    );

    const [messageRef, scrollRef] = useSnapScroll();

    useEffect(() => {
      const storedApiKeys = Cookies.get('apiKeys');

      if (storedApiKeys) {
        setApiKeys(JSON.parse(storedApiKeys));
      }
    }, []);

    const handleModelChange = (newModel: string) => {
      setModel(newModel);
      Cookies.set('selectedModel', newModel, { expires: 30 });
    };

    const handleProviderChange = (newProvider: ProviderInfo) => {
      setProvider(newProvider);
      Cookies.set('selectedProvider', newProvider.name, { expires: 30 });
    };

    return (
      <BaseChat
        ref={animationScope}
        textareaRef={textareaRef}
        input={input}
        showChat={showChat}
        chatStarted={chatStarted}
        isStreaming={isLoading}
        enhancingPrompt={enhancingPrompt}
        promptEnhanced={promptEnhanced}
        sendMessage={sendMessage}
        model={model}
        setModel={handleModelChange}
        provider={provider}
        setProvider={handleProviderChange}
        messageRef={messageRef}
        scrollRef={scrollRef}
        handleInputChange={(e) => {
          onTextareaChange(e);
          debouncedCachePrompt(e);
        }}
        handleStop={abort}
        description={description}
        importChat={importChat}
        exportChat={exportChat}
        messages={messages.map((message, i) => {
          if (message.role === 'user') {
            return message;
          }

          return {
            ...message,
            content: parsedMessages[i] || '',
          };
        })}
        enhancePrompt={() => {
          enhancePrompt(
            input,
            (input) => {
              setInput(input);
              scrollTextArea();
            },
            model,
            provider,
            apiKeys,
          );
        }}
        uploadedFiles={uploadedFiles}
        setUploadedFiles={setUploadedFiles}
        imageDataList={imageDataList}
        setImageDataList={setImageDataList}
      />
    );
  },
);