import type { MarkdownIt } from "markdown-it";

// The `-`/`+` after the type is Obsidian's fold marker: `-` starts collapsed, `+` starts
// open, absent means not foldable at all. Without this group it lands in the title.
const CALLOUT_RE = /^\[!(\w+)\]([-+])?\s*(.*)?$/;

const TYPE_ALIASES: Record<string, string> = {
	info: "note",
	hint: "tip",
	caution: "warning",
	bug: "danger",
	cite: "quote",
	summary: "abstract",
	tldr: "abstract",
	check: "success",
	done: "success",
	help: "question",
	faq: "question",
	fail: "failure",
	missing: "failure",
};

function normalizeType(raw: string): string {
	const lower = raw.toLowerCase();
	return TYPE_ALIASES[lower] ?? lower;
}

export function calloutPlugin(mdi: MarkdownIt): void {
	mdi.core.ruler.after("block", "callout", (state) => {
		const tokens = state.tokens;
		for (let i = 0; i < tokens.length; i++) {
			const open = tokens[i];
			if (open?.type !== "blockquote_open") continue;

			const paraOpen = tokens[i + 1];
			const inline = tokens[i + 2];
			if (paraOpen?.type !== "paragraph_open") continue;
			if (inline?.type !== "inline") continue;

			const lines = inline.content.split("\n");
			const firstLine = lines[0] ?? "";
			const match = CALLOUT_RE.exec(firstLine);
			if (!match) continue;

			const type = normalizeType(match[1] ?? "");
			const fold = match[2] ?? "";
			const customTitle = match[3]?.trim() || null;
			const title = customTitle || type.charAt(0).toUpperCase() + type.slice(1);

			open.type = "callout_open";
			open.tag = fold ? "details" : "div";
			open.info = fold;
			open.attrSet("class", `callout callout-${type}`);

			const titleOpen = new state.Token(
				"callout_title_open",
				fold ? "summary" : "p",
				1,
			);
			titleOpen.info = fold;
			titleOpen.attrSet("class", "callout-title");
			const titleInline = new state.Token("inline", "", 0);
			titleInline.content = title;
			titleInline.children = [];
			const titleClose = new state.Token(
				"callout_title_close",
				fold ? "summary" : "p",
				-1,
			);
			titleClose.info = fold;

			lines.shift();
			const remaining = lines.join("\n").trim();

			if (remaining) {
				inline.content = remaining;
				tokens.splice(i + 1, 0, titleOpen, titleInline, titleClose);
			} else {
				const paraClose = tokens[i + 3];
				if (paraClose?.type === "paragraph_close") {
					tokens.splice(i + 1, 3, titleOpen, titleInline, titleClose);
				} else {
					inline.content = remaining;
					tokens.splice(i + 1, 0, titleOpen, titleInline, titleClose);
				}
			}

			let depth = 1;
			for (let j = i + 1; j < tokens.length; j++) {
				if (tokens[j]?.type === "blockquote_open") depth++;
				if (tokens[j]?.type === "callout_open") depth++;
				if (
					tokens[j]?.type === "blockquote_close" ||
					tokens[j]?.type === "callout_close"
				) {
					depth--;
					if (depth === 0) {
						const closeToken = tokens[j];
						if (closeToken) {
							closeToken.type = "callout_close";
							closeToken.tag = fold ? "details" : "div";
							closeToken.info = fold;
						}
						break;
					}
				}
			}
		}
	});

	mdi.renderer.rules["callout_open"] = (tokens, idx) => {
		const token = tokens[idx];
		const cls = token?.attrGet("class") ?? "callout";
		if (!token?.info) return `<div class="${cls}">\n`;
		return `<details class="${cls}"${token.info === "+" ? " open" : ""}>\n`;
	};

	mdi.renderer.rules["callout_close"] = (tokens, idx) =>
		tokens[idx]?.info ? "</details>\n" : "</div>\n";

	mdi.renderer.rules["callout_title_open"] = (tokens, idx) => {
		const token = tokens[idx];
		const cls = token?.attrGet("class") ?? "callout-title";
		if (!token?.info) return `<p class="${cls}">`;
		return `<summary class="${cls}"><span class="callout-fold" aria-hidden="true">▸</span>`;
	};

	mdi.renderer.rules["callout_title_close"] = (tokens, idx) =>
		tokens[idx]?.info ? "</summary>\n" : "</p>\n";
}