app/components/markdown.tsx

import ReactMarkdown from "react-markdown";
import "katex/dist/katex.min.css";
import RemarkMath from "remark-math";
import RemarkBreaks from "remark-breaks";
import RehypeKatex from "rehype-katex";
import RemarkGfm from "remark-gfm";
import RehypePrsim from "rehype-prism-plus";
import { useRef } from "react";
import { copyToClipboard } from "../utils";

export function PreCode(props: { children: any }) {
  const ref = useRef<HTMLPreElement>(null);

  return (
    <pre ref={ref}>
      <span
        className="copy-code-button"
        onClick={() => {
          if (ref.current) {
            const code = ref.current.innerText;
            copyToClipboard(code);
          }
        }}
      ></span>
      {props.children}
    </pre>
  );
}

export function Markdown(props: { content: string }) {
  return (
    <ReactMarkdown
      remarkPlugins={[RemarkMath, RemarkGfm, RemarkBreaks]}
      rehypePlugins={[RehypeKatex, [RehypePrsim, { ignoreMissing: true }]]}
      components={{
        pre: PreCode,
      }}
    >
      {props.content}
    </ReactMarkdown>
  );
}