import { removeMediaFile } from "../lib/mediaTier-server";
import path from "node:path";
import fs from "fs-extra";
import type { Paths } from "../lib/paths";
import { isDoNotClean } from "../lib/doNotClean-server";
import { audioFilesToRemove } from "../lib/videoStatus";
import { readChannelConfig } from "./channels";

const { pathExists, readdir, remove } = fs;

export type CleanExtraAudioFormatsOptions = {
  channelSlug: string;
  paths: Paths;
  onLog?: (msg: string) => void;
  signal?: AbortSignal;
};

export type CleanExtraAudioFormatsResult = {
  inspected: number;
  cleanedDirs: number;
  removedFiles: number;
  skipped: number;
};

export async function cleanExtraAudioFormats({
  channelSlug,
  paths,
  onLog,
  signal,
}: CleanExtraAudioFormatsOptions): Promise<CleanExtraAudioFormatsResult> {
  const log = onLog ?? ((m: string) => console.log(m));
  const config = await readChannelConfig(paths, channelSlug);
  if (!config?.audioFormat) {
    log(
      `No audioFormat configured for ${channelSlug}; nothing to clean (set the channel's audio format first).`,
    );
    return { inspected: 0, cleanedDirs: 0, removedFiles: 0, skipped: 0 };
  }
  const targetAudioFile = `audio.${config.audioFormat}`;
  const dataDir = path.join(paths.channelsDir, channelSlug, "data");
  if (!(await pathExists(dataDir))) {
    log(`No data directory for ${channelSlug}`);
    return { inspected: 0, cleanedDirs: 0, removedFiles: 0, skipped: 0 };
  }
  const dirs = await readdir(dataDir);

  let cleanedDirs = 0;
  let removedFiles = 0;
  let skipped = 0;

  for (const id of dirs) {
    if (signal?.aborted) {
      log("Cancelled");
      break;
    }
    const videoDir = path.join(dataDir, id);
    const entries = await readdir(videoDir).catch(() => [] as string[]);
    if (!entries.includes(targetAudioFile)) continue;
    // Shares the app's one media-file predicate rather than re-deriving it. The
    // inline copy that used to live here was a stale fork of the old denylist:
    // it excluded .tmp-/.info.json/.part and nothing else, so an
    // audio.en-orig.vtt subtitle or an audio.live_chat.json.part-Frag114
    // fragment sitting next to the target format was deleted as an "extra audio
    // format" — by an unguarded remove(), in a sweep with no dry run.
    const extras = audioFilesToRemove(entries, {
      targetAudioFile,
      wrongFormatOnly: true,
    });
    if (extras.length === 0) continue;
    if (await isDoNotClean(videoDir)) {
      log(`Skipped ${id} (marked do not clean)`);
      skipped++;
      continue;
    }
    for (const f of extras) {
      await removeMediaFile(videoDir, f); // derefs a tiered link (release 17)
      log(`Removed ${id}/${f}`);
      removedFiles++;
    }
    cleanedDirs++;
  }

  const skippedNote = skipped > 0 ? ` Skipped ${skipped} (do not clean).` : "";
  log(
    `Cleaned ${removedFiles} extra audio file(s) from ${cleanedDirs} of ${dirs.length} video dir(s) (kept ${targetAudioFile}).${skippedNote}`,
  );
  return { inspected: dirs.length, cleanedDirs, removedFiles, skipped };
}