import type { User } from "@markone/core/user"
import { Readability } from "@mozilla/readability"
import { JSDOM } from "jsdom"
import { db } from "~/database.ts"
import { DEMO_BOOKMARKS } from "./demo-bookmarks.ts"
import type { Bookmark, BookmarkTag } from "@markone/core/bookmark"

class LinkUnreachable {}
class UnsupportedLink {}

interface CachedPage {
	title: string
	readableHtml: string
}

function insertDemoBookmarks(user: User) {
	const query = db.query(`
INSERT OR IGNORE INTO bookmarks (id, user_id, kind, title, url)
VALUES ($id, $userId, $kind, $title, $url)
`)
	const insert = db.transaction((bookmarks) => {
		for (const bookmark of bookmarks) {
			query.run({
				id: bookmark.id,
				userId: user.id,
				kind: bookmark.kind,
				title: bookmark.title,
				url: bookmark.url,
			})
		}
	})
	insert(DEMO_BOOKMARKS)
}

function findBookmarkHtml(id: string, user: User): string | null {
	const query = db.query("SELECT content_html FROM bookmarks WHERE id = $id AND user_id = $userId")
	const row = query.get({ id, userId: user.id })
	if (!row) {
		return null
	}
	const { content_html } = row as { content_html: string }
	return content_html
}

function findBookmark(id: string, user: User): Bookmark | null {
	const bookmarkQuery = db.query<Bookmark, { id: string; userId: string }>(
		"SELECT id, kind, title, url FROM bookmarks WHERE id = $id AND user_id = $userId",
	)
	const bookmark = bookmarkQuery.get({ id, userId: user.id })
	if (!bookmark) {
		return null
	}

	const tagsQuery = db.query<BookmarkTag, { id: string }>("SELECT id, name FROM tags WHERE bookmark_id = $id")
	const tags = tagsQuery.all({ id })

	bookmark.tags = tags

	return bookmark
}

async function cacheWebsite(url: string): Promise<CachedPage | null> {
	const websiteText = await fetch(url)
		.catch(() => {
			throw new LinkUnreachable()
		})
		.then((res) => res.text())
		.catch(() => {
			throw new UnsupportedLink()
		})

	const dom = new JSDOM(websiteText, { url })
	const reader = new Readability(dom.window.document)
	const article = reader.parse()

	if (!article) {
		return null
	}

	if (article.content) {
		const newDom = new JSDOM(article.content, { url })
		const doc = newDom.window.document

		const lightStyleLink = doc.createElement("link")
		lightStyleLink.rel = "stylesheet"
		lightStyleLink.href = "/reader-styles/sakura.css"
		lightStyleLink.media = "screen"

		const darkStyleLink = doc.createElement("link")
		darkStyleLink.rel = "stylesheet"
		darkStyleLink.href = "/reader-styles/sakura-dark.css"
		darkStyleLink.media = "screen and (prefers-color-scheme: dark)"

		doc.head.appendChild(lightStyleLink)
		doc.head.appendChild(darkStyleLink)

		article.content = newDom.serialize()
	}

	return {
		title: article.title || "Untitled",
		readableHtml: article.content || "",
	}
}

export { insertDemoBookmarks, findBookmark, findBookmarkHtml, cacheWebsite }
export { LinkUnreachable, UnsupportedLink }