buzz/desktop/src/features/messages/lib/parseImeta.ts

export type ImetaEntry = {
  url: string;
  m: string;
  x: string;
  size: number;
  dim?: string;
  blurhash?: string;
  alt?: string;
  thumb?: string;
  duration?: number;
  image?: string;
};

export function parseImetaTags(tags: string[][]): Map<string, ImetaEntry> {
  const map = new Map<string, ImetaEntry>();
  for (const tag of tags) {
    if (tag[0] !== "imeta") continue;
    const entry: Partial<ImetaEntry> = {};
    for (const part of tag.slice(1)) {
      const spaceIdx = part.indexOf(" ");
      if (spaceIdx === -1) continue;
      const key = part.slice(0, spaceIdx);
      const val = part.slice(spaceIdx + 1);
      switch (key) {
        case "url":
          entry.url = val;
          break;
        case "m":
          entry.m = val;
          break;
        case "x":
          entry.x = val;
          break;
        case "size":
          entry.size = parseInt(val, 10);
          break;
        case "dim":
          entry.dim = val;
          break;
        case "blurhash":
          entry.blurhash = val;
          break;
        case "alt":
          entry.alt = val;
          break;
        case "thumb":
          entry.thumb = val;
          break;
        case "duration":
          entry.duration = parseFloat(val);
          break;
        case "image":
          entry.image = val;
          break;
      }
    }
    if (entry.url) map.set(entry.url, entry as ImetaEntry);
  }
  return map;
}