import ReactMarkdown from "react-markdown"
import remarkGfm from "remark-gfm"
import CodeBlock from "@/components/CodeBlock"
import remarkMath from "remark-math"
import rehypeKatex from "rehype-katex"
import "katex/dist/katex.min.css"
import BodyLink from "./BodyLink"
import EntryLoadingSkeleton from "./EntryLoadingSkeleton"
import { useSearchParams } from "react-router"
import { Table, TableBody, TableCell, TableHead, TableHeader, TableRow } from "./ui/table"
const ImagePreprocessor = (src) => {
	const filename = src.src.split("/").pop()
	const s3RootUrl = "https://eolas.s3.systemsobscure.net/"
	return <img src={s3RootUrl + filename} />
}

const escapeRegex = (str) => str.replace(/[.*+?^${}()|[\]\\]/g, "\\$&")

const highlighter = (children, highlight) => {
	if (!highlight || typeof children !== "string") return children
	const words = highlight.trim().split(/\s+/)
	const pattern = words.length > 1 ? escapeRegex(highlight) : escapeRegex(words[0])
	const regex = new RegExp(`\\b(${pattern})\\b`, "gi")
	const parts = children.split(regex)

	return parts.map((part, i) =>
		regex.test(part) ? (
			<mark key={i} className="dark:bg-[#4c1d95] dark:text-white bg-[#ddd6fe]">
				{part}
			</mark>
		) : (
			part
		),
	)
}

export default function EntryBody({ body, isLoading }) {
	const [searchParams] = useSearchParams()

	const highlight = searchParams.get("highlight")

	if (isLoading) {
		return <EntryLoadingSkeleton />
	}
	return (
		<div className="max-w-2xl p-4 lg:p-6">
			<ReactMarkdown
				remarkPlugins={[remarkGfm, remarkMath]}
				rehypePlugins={[rehypeKatex]}
				components={{
					h1: () => null,
					h2: ({ children }) => (
						<h2 className="scroll-m-20 font-semibold mt-8 mb-4 first:mt-0">
							{highlighter(children, highlight)}
						</h2>
					),
					h3: ({ children }) => (
						<h3 className="scroll-m-20 font-semibold mt-8 mb-4 first:mt-0">
							{highlighter(children, highlight)}
						</h3>
					),
					h4: ({ children }) => (
						<h4 className="scroll-m-20 font-semibold mt-8 mb-4 first:mt-0">
							{highlighter(children, highlight)}
						</h4>
					),
					p: ({ children }) => (
						<p className="leading-[1.5] mb-4 not-first:mt-4">
							{highlighter(children, highlight)}
						</p>
					),
					ul: ({ children }) => <ul className="list-disc ml-10 mb-4 space-y-1">{children}</ul>,
					ol: ({ children }) => (
						<ol className="list-decimal ml-10 mb-4 space-y-1">{children}</ol>
					),
					li: ({ children }) => (
						<li className="list-disc mb-4 space-y-1">{highlighter(children, highlight)}</li>
					),
					table: ({ children }) => (
						<Table className="w-full mb-4 text-sm overflow-x-auto">{children}</Table>
					),
					thead: ({ children }) => <TableHeader>{children}</TableHeader>,

					tr: ({ children }) => <TableRow>{highlighter(children, highlight)}</TableRow>,

					th: ({ children }) => <TableHead>{highlighter(children, highlight)}</TableHead>,
					td: ({ children }) => <TableCell>{highlighter(children, highlight)}</TableCell>,
					tbody: ({ children }) => <TableBody>{children}</TableBody>,

					blockquote: ({ children }) => (
						<blockquote className="mt-4 border-l-2 pl-6 text-muted-foreground">
							{highlighter(children, highlight)}
						</blockquote>
					),
					pre: ({ children }) => {
						const child = children.props
						return <CodeBlock className={child.className}>{child.children}</CodeBlock>
					},
					code: ({ children }) => (
						<code className="rounded bg-muted px-[0.3rem] py-[0.2rem] font-mono text-sm">
							{children}
						</code>
					),
					img: ({ src }) => <ImagePreprocessor src={src} />,
					a: ({ href, children }) => {
						return <BodyLink link={href} children={children} />
					},
				}}
			>
				{body}
			</ReactMarkdown>
		</div>
	)
}