import * as fs from "fs";
import * as path from "path";

function toSrtTime(secondsFloat: number): string {
  const totalMs = Math.max(0, Math.round(secondsFloat * 1000));
  const hours = Math.floor(totalMs / 3600000);
  const minutes = Math.floor((totalMs % 3600000) / 60000);
  const seconds = Math.floor((totalMs % 60000) / 1000);
  const ms = totalMs % 1000;
  const pad = (n: number, w: number) => n.toString().padStart(w, "0");
  return `${pad(hours, 2)}:${pad(minutes, 2)}:${pad(seconds, 2)},${pad(ms, 3)}`;
}

export function createSrt(storyName: string, chunks: string[], chunkDurations: number[]): string {
  const srtPath = path.resolve("stories", storyName, "subtitles.srt");
  let srtContent = "";
  let currentTime = 0;

  for (let i = 0; i < chunks.length; i++) {
    const chunk = chunks[i];
    const duration = chunkDurations[i];
    const startTime = toSrtTime(currentTime);
    const endTime = toSrtTime(currentTime + duration);

    srtContent += `${i + 1}\n`;
    srtContent += `${startTime} --> ${endTime}\n`;
    srtContent += `${chunk}\n\n`;

    currentTime += duration;
  }

  fs.writeFileSync(srtPath, srtContent);
  return srtPath;
}