import type { AssetRef, TTSMod, TTSObject } from '@tts/shared';
import { markParent, traverseMod } from './traverse.js';

/**
 * Extract every external asset reference from a single object.
 */
export function extractRefs(o: TTSObject): AssetRef[] {
  const refs: AssetRef[] = [];
  const ownerGuid = o.GUID;

  if (o.CustomPDF?.PDFUrl) {
    refs.push({ kind: 'pdf', url: o.CustomPDF.PDFUrl, ownerGuid });
  }

  if (o.CustomDeck) {
    for (const deck of Object.values(o.CustomDeck)) {
      if (deck.FaceURL) {
        refs.push({ kind: 'deckFace', url: deck.FaceURL, ownerGuid });
      }
      if (deck.BackURL) {
        refs.push({ kind: 'deckBack', url: deck.BackURL, ownerGuid });
      }
    }
  }

  if (o.CustomImage?.ImageURL) {
    refs.push({ kind: 'image', url: o.CustomImage.ImageURL, ownerGuid });
  }
  if (o.CustomImage?.ImageSecondaryURL) {
    refs.push({
      kind: 'imageSecondary',
      url: o.CustomImage.ImageSecondaryURL,
      ownerGuid,
    });
  }

  return refs;
}

/**
 * Collect all asset references across a whole save, deduped by URL.
 */
export function collectRefs(mod: TTSMod): AssetRef[] {
  for (const state of mod.ObjectStates) {
    markParent(state);
  }
  const seen = new Set<string>();
  const refs: AssetRef[] = [];
  for (const o of traverseMod(mod)) {
    for (const ref of extractRefs(o)) {
      if (!seen.has(ref.url)) {
        seen.add(ref.url);
        refs.push(ref);
      }
    }
  }
  return refs;
}

export { markParent, traverseMod } from './traverse.js';