import features from "../../../features";
import log from "../../../log";
import type { ISupportedTextTrackFormat } from "../../../transports";

export interface IHTMLCue {
  start: number;
  end: number;
  element: HTMLElement;
}

/**
 * Convert text track data into timed HTML Cues.
 * @param {string} type - Text track format wanted
 * @param {string} data - Text track data
 * @param {Object} context
 * @param {Number} timestampOffset - offset to apply to every timed text
 * @returns {Array.<Object>}
 * @throws Error - Throw if no parser is found for the given type
 */
export default function parseTextTrackToElements(
  type: ISupportedTextTrackFormat,
  data: string | BufferSource,
  context: {
    initTimescale: number | null;
    language: string | undefined;
  },
  timestampOffset: number,
): IHTMLCue[] {
  log.debug("text", "Finding parser for html text tracks:", { type });
  const parser = features.htmlTextTracksParsers[type];

  if (typeof parser !== "function") {
    throw new Error("no parser found for the given text track");
  }
  log.debug("text", "Parser found, parsing...", { type });
  const parsed = parser(data, context, timestampOffset);
  log.debug("text", "Parsed successfully!", { length: parsed.length });
  return parsed;
}