/**
 * Obsidian-compatible [[wiki-link]] extraction from note bodies.
 * Pure module used by graph construction and viewer view-models.
 */

import { slugify } from "../slug";

const WIKILINK_RE = /\[\[([^\][|]+)(?:\|[^\]]*)?\]\]/g;

/**
 * Extract wiki-link targets from a note body as slugs. Handles
 * `[[some-note]]` and aliased `[[Some Note|alias]]` (alias ignored for
 * linking). Targets are slugified so `[[Release Plan]]` matches the note
 * `release-plan`. Duplicates are removed, order of first appearance kept.
 *
 * Path separators survive: a nested note's slug is its path relative to
 * `notes/`, so links target the nested note rather than a flattened name.
 * Each path segment is slugified independently.
 */
export function extractWikilinks(body: string): string[] {
  const out: string[] = [];
  const seen = new Set<string>();
  for (const match of body.matchAll(WIKILINK_RE)) {
    const raw = (match[1] ?? "").trim();
    if (raw.length === 0) continue;
    // HTML artifacts are addressed by their vault-relative filename; unlike a
    // Markdown note, the extension is part of the stable identity.
    const slug = /\.html?$/i.test(raw)
      ? raw.replace(/\\/g, "/").replace(/^\.\//, "")
      : raw.split("/").map((part) => slugify(part)).join("/");
    if (seen.has(slug)) continue;
    seen.add(slug);
    out.push(slug);
  }
  return out;
}