import { InputRule, markInputRule, markPasteRule, PasteRule } from '@tiptap/core';
import { Link } from '@tiptap/extension-link';

import type { LinkOptions } from '@tiptap/extension-link';

/**
 * The input regex for Markdown links with title support, and multiple quotation marks (required
 * in case the `Typography` extension is being included).
 */
const inputRegex = /(?:^|\s)\[([^\]]*)?\]\((\S+)(?: ["“](.+)["”])?\)$/i;

/**
 * The paste regex for Markdown links with title support, and multiple quotation marks (required
 * in case the `Typography` extension is being included).
 */
const pasteRegex = /(?:^|\s)\[([^\]]*)?\]\((\S+)(?: ["“](.+)["”])?\)/gi;

/**
 * Input rule built specifically for the `Link` extension, which ignores the auto-linked URL in
 * parentheses (e.g., `(https://doist.dev)`).
 *
 * @see https://github.com/ueberdosis/tiptap/discussions/1865
 */
function linkInputRule(config: Parameters<typeof markInputRule>[0]) {
	const defaultMarkInputRule = markInputRule(config);

	return new InputRule({
		find: config.find,
		handler(props) {
			const { tr } = props.state;

			defaultMarkInputRule.handler(props);
			tr.setMeta('preventAutolink', true);
		}
	});
}

/**
 * Paste rule built specifically for the `Link` extension, which ignores the auto-linked URL in
 * parentheses (e.g., `(https://doist.dev)`). This extension was inspired from the multiple
 * implementations found in a Tiptap discussion at GitHub.
 *
 * @see https://github.com/ueberdosis/tiptap/discussions/1865
 */
function linkPasteRule(config: Parameters<typeof markPasteRule>[0]) {
	const defaultMarkPasteRule = markPasteRule(config);

	return new PasteRule({
		find: config.find,
		handler(props) {
			const { tr } = props.state;

			defaultMarkPasteRule.handler(props);
			tr.setMeta('preventAutolink', true);
		}
	});
}

/**
 * The options available to customize the `RichTextLink` extension.
 */
type RichTextLinkOptions = LinkOptions;

/**
 * Custom extension that extends the built-in `Link` extension to add additional input/paste rules
 * for converting the Markdown link syntax (i.e. `[Doist](https://doist.com)`) into links, and also
 * adds support for the `title` attribute.
 */
const RichTextLink = Link.extend<RichTextLinkOptions>({
	inclusive: false,
	addOptions(): LinkOptions {
		return {
			...this.parent?.(),
			openOnClick: 'whenNotEditable'
		} as LinkOptions;
	},
	addAttributes() {
		return {
			...this.parent?.(),
			title: {
				default: null
			}
		};
	},
	addInputRules() {
		return [
			linkInputRule({
				find: inputRegex,
				type: this.type,

				// We need to use `pop()` to remove the last capture groups from the match to
				// satisfy Tiptap's `markPasteRule` expectation of having the content as the last
				// capture group in the match (this makes the attribute order important)
				getAttributes(match) {
					return {
						title: match.pop()?.trim(),
						href: match.pop()?.trim()
					};
				}
			})
		];
	},
	addPasteRules() {
		return [
			linkPasteRule({
				find: pasteRegex,
				type: this.type,

				// We need to use `pop()` to remove the last capture groups from the match to
				// satisfy Tiptap's `markInputRule` expectation of having the content as the last
				// capture group in the match (this makes the attribute order important)
				getAttributes(match) {
					return {
						title: match.pop()?.trim(),
						href: match.pop()?.trim()
					};
				}
			})
		];
	}
});

export { RichTextLink };

export type { RichTextLinkOptions };