import { Plugin } from 'prosemirror-state';
import { isSafeUrl } from '../sanitize';

const URL_PATTERN = /^https?:\/\/\S+$/i;

export interface LinkPluginOptions {
  /** Called with the href when a link is Mod/Ctrl-clicked. */
  onOpenLink?: (href: string) => void;
}

/**
 * Link behaviors that belong to the document, not the chrome:
 * - Mod/Ctrl-click opens the link.
 * - Pasting a bare URL over a text selection turns the selection into a link.
 */
export function linkPlugin(options: LinkPluginOptions = {}): Plugin {
  return new Plugin({
    props: {
      handleClick(view, _pos, event) {
        if (!(event.metaKey || event.ctrlKey)) return false;
        const target = (event.target as HTMLElement | null)?.closest?.('a[href]');
        if (!target) return false;
        const href = target.getAttribute('href')!;
        if (!isSafeUrl(href)) return false;
        if (options.onOpenLink) options.onOpenLink(href);
        else window.open(href, '_blank', 'noopener,noreferrer');
        return true;
      },

      handlePaste(view, event) {
        const { state } = view;
        const { empty, from, to } = state.selection;
        if (empty) return false;
        const text = event.clipboardData?.getData('text/plain')?.trim();
        if (!text || !URL_PATTERN.test(text) || !isSafeUrl(text)) return false;
        const linkMark = state.schema.marks.link.create({ href: text });
        view.dispatch(state.tr.addMark(from, to, linkMark));
        return true;
      },
    },
  });
}