import React, {
  FC, memo, useCallback, useState,
} from '../../../lib/teact/teact';

import buildClassName from '../../../util/buildClassName';

import useAsync from '../../../hooks/useAsync';

import PreBlock from './PreBlock';
import CodeOverlay from './CodeOverlay';

import './CodeBlock.scss';

export type OwnProps = {
  text: string;
  language?: string;
  noCopy?: boolean;
};

const CodeBlock: FC<OwnProps> = ({ text, language, noCopy }) => {
  const [isWordWrap, setWordWrap] = useState(true);

  const { result: highlighted } = useAsync(() => {
    if (!language) return Promise.resolve();
    return import('../../../util/highlightCode')
      .then((lib) => lib.default(text, language));
  }, [language, text]);

  const handleWordWrapToggle = useCallback((wrap) => {
    setWordWrap(wrap);
  }, []);

  if (!highlighted) {
    return <PreBlock text={text} noCopy={noCopy} />;
  }

  const blockClass = buildClassName('code-block', !isWordWrap && 'no-word-wrap');

  return (
    <pre className={blockClass}>
      {highlighted}
      <CodeOverlay
        text={text}
        className="code-overlay"
        onWordWrapToggle={handleWordWrapToggle}
        noCopy={noCopy}
      />
    </pre>
  );
};

export default memo(CodeBlock);
