import { useState, useRef, useCallback, useEffect, FunctionComponent } from 'react';

import {
  Page,
  Masthead,
  MastheadMain,
  MastheadBrand,
  MastheadLogo,
  PageSidebarBody,
  PageSidebar,
  MastheadToggle,
  PageToggleButton
} from '@patternfly/react-core';
import Chatbot, { ChatbotDisplayMode } from '@patternfly/chatbot/dist/dynamic/Chatbot';
import ChatbotContent from '@patternfly/chatbot/dist/dynamic/ChatbotContent';
import ChatbotWelcomePrompt from '@patternfly/chatbot/dist/dynamic/ChatbotWelcomePrompt';
import ChatbotFooter from '@patternfly/chatbot/dist/dynamic/ChatbotFooter';
import MessageBar from '@patternfly/chatbot/dist/dynamic/MessageBar';
import MessageBox from '@patternfly/chatbot/dist/dynamic/MessageBox';
import Message, { MessageProps } from '@patternfly/chatbot/dist/dynamic/Message';
import ChatbotHeader, { ChatbotHeaderMain } from '@patternfly/chatbot/dist/dynamic/ChatbotHeader';
import Compare from '@patternfly/chatbot/dist/dynamic/Compare';
import { BarsIcon } from '@patternfly/react-icons';
import userAvatar from '../Messages/user_avatar.svg';
import patternflyAvatar from '../Messages/patternfly_avatar.jpg';
import '@patternfly/react-core/dist/styles/base.css';
import '@patternfly/chatbot/dist/css/main.css';

export const CompareChild = ({ name, input, hasNewInput, setIsSendButtonDisabled }) => {
  const [messages, setMessages] = useState<MessageProps[]>([]);
  const [announcement, setAnnouncement] = useState<string>();
  const scrollToBottomRef = useRef<HTMLDivElement>(null);
  const displayMode = ChatbotDisplayMode.embedded;

  // you will likely want to come up with your own unique id function; this is for demo purposes only
  const generateId = () => {
    const id = Date.now() + Math.random();
    return id.toString();
  };

  const handleSend = useCallback(
    (input: string) => {
      const date = new Date();
      const newMessages: MessageProps[] = [];
      messages.forEach((message) => newMessages.push(message));
      newMessages.push({
        avatar: userAvatar,
        avatarProps: { isBordered: true },
        id: generateId(),
        name: 'You',
        role: 'user',
        content: input,
        timestamp: `${date?.toLocaleDateString()} ${date?.toLocaleTimeString()}`
      });
      newMessages.push({
        avatar: patternflyAvatar,
        id: generateId(),
        name,
        role: 'bot',
        timestamp: `${date?.toLocaleDateString()} ${date?.toLocaleTimeString()}`,
        isLoading: true
      });
      setMessages(newMessages);
      // make announcement to assistive devices that new messages have been added
      setAnnouncement(`Message from You: ${input}. Message from ${name} is loading.`);

      // this is for demo purposes only; in a real situation, there would be an API response we would wait for
      setTimeout(() => {
        const loadedMessages: MessageProps[] = [];
        // we can't use structuredClone since messages contains functions, but we can't mutate
        // items that are going into state or the UI won't update correctly
        newMessages.forEach((message) => loadedMessages.push(message));
        loadedMessages.pop();
        loadedMessages.push({
          id: generateId(),
          role: 'bot',
          content: `API response from ${name} goes here`,
          name,
          avatar: patternflyAvatar,
          isLoading: false,
          actions: {
            // eslint-disable-next-line no-console
            positive: { onClick: () => console.log('Good response') },
            // eslint-disable-next-line no-console
            negative: { onClick: () => console.log('Bad response') },
            // eslint-disable-next-line no-console
            copy: { onClick: () => console.log('Copy') },
            // eslint-disable-next-line no-console
            download: { onClick: () => console.log('Download') },
            // eslint-disable-next-line no-console
            listen: { onClick: () => console.log('Listen') }
          },
          timestamp: date.toLocaleString()
        });
        setMessages(loadedMessages);
        // make announcement to assistive devices that new message has loaded
        setAnnouncement(`Message from ${name}: API response goes here`);
        setIsSendButtonDisabled(false);
      }, 5000);
    },
    [messages, name, setIsSendButtonDisabled]
  );

  useEffect(() => {
    if (input) {
      handleSend(input);
    }
  }, [hasNewInput, input]);

  // Auto-scrolls to the latest message
  useEffect(() => {
    // don't scroll the first load, but scroll if there's a current stream or a new source has popped up
    if (messages.length > 0) {
      scrollToBottomRef.current?.scrollIntoView();
    }
  }, [messages]);

  return (
    <Chatbot displayMode={displayMode}>
      <ChatbotHeader>
        <ChatbotHeaderMain>{name}</ChatbotHeaderMain>
      </ChatbotHeader>
      <ChatbotContent>
        <MessageBox ariaLabel={`Scrollable message log for ${name}`} announcement={announcement}>
          <ChatbotWelcomePrompt title="Hi, ChatBot User!" description="How can I help you today?" />
          {messages.map((message) => (
            <Message key={message.id} {...message} />
          ))}
          <div ref={scrollToBottomRef}></div>
        </MessageBox>
      </ChatbotContent>
    </Chatbot>
  );
};

export const EmbeddedComparisonChatbotDemo: FunctionComponent = () => {
  const [input, setInput] = useState<string>();
  const [hasNewInput, setHasNewInput] = useState(false);
  const [isSidebarOpen, setIsSidebarOpen] = useState(false);
  const [isSendButtonDisabled, setIsSendButtonDisabled] = useState(false);

  const handleSend = (value: string) => {
    setInput(value);
    setHasNewInput(!hasNewInput);
    setIsSendButtonDisabled(true);
  };

  const masthead = (
    <Masthead>
      <MastheadMain>
        <MastheadToggle>
          <PageToggleButton
            variant="plain"
            aria-label="Global navigation"
            isSidebarOpen={isSidebarOpen}
            onSidebarToggle={() => setIsSidebarOpen(!isSidebarOpen)}
            id="fill-nav-toggle"
          >
            <BarsIcon />
          </PageToggleButton>
        </MastheadToggle>
        <MastheadBrand>
          <MastheadLogo href="https://patternfly.org" target="_blank">
            Logo
          </MastheadLogo>
        </MastheadBrand>
      </MastheadMain>
    </Masthead>
  );

  const sidebar = (
    <PageSidebar isSidebarOpen={isSidebarOpen} id="fill-sidebar">
      <PageSidebarBody>Navigation</PageSidebarBody>
    </PageSidebar>
  );

  return (
    <Page masthead={masthead} sidebar={sidebar} isContentFilled>
      <div className="pf-chatbot__compare-container">
        <Compare
          firstChild={
            <CompareChild
              input={input}
              hasNewInput={hasNewInput}
              name="ChatBot 1"
              setIsSendButtonDisabled={setIsSendButtonDisabled}
            />
          }
          secondChild={
            <CompareChild
              input={input}
              hasNewInput={hasNewInput}
              name="ChatBot 2"
              setIsSendButtonDisabled={setIsSendButtonDisabled}
            />
          }
          firstChildDisplayName="ChatBot 1"
          secondChildDisplayName="ChatBot 2"
        />
        <ChatbotFooter>
          <MessageBar
            onSendMessage={handleSend}
            hasAttachButton={false}
            alwayShowSendButton
            isSendButtonDisabled={isSendButtonDisabled}
          />
        </ChatbotFooter>
      </div>
    </Page>
  );
};