"use server";

import { revalidatePath } from "next/cache";
import { safeRevalidate } from "../lib/safeRevalidate";
import { getPaths } from "yt-dlp-transcript-common/lib/paths";
import { getSettings } from "yt-dlp-transcript-common/lib/settings";
import { saveSettings } from "../settings/saveSettings";
import { SYNC_INTERVAL_MAX_MINUTES } from "yt-dlp-transcript-common/lib/channelConfig";
import { formValues, type FormState } from "../lib/formState";
import {
  backupSavedVideos,
  verifySavedVideoBackup,
} from "yt-dlp-transcript-common/controller/backupSavedVideos";
import {
  runManagedFunction,
  type StreamActionResult,
} from "yt-dlp-transcript-common/jobs/streamCommand";

// Saved-video backups are a global (not per-channel) concern, so they share a
// dedicated queue rather than a channel queue.
const SAVED_VIDEOS_QUEUE = "saved-videos";

// Mirror the saved-video store to the configured backup destination and write a
// fresh manifest. The destination comes from settings (savedVideoBackup.dest);
// an explicit `dest` overrides it for an ad-hoc run.
export async function backupSavedVideosAction(
  dest?: string,
  queueKey?: string,
): Promise<StreamActionResult> {
  const paths = getPaths();
  const settings = getSettings();
  const target = (dest ?? settings.savedVideoBackup.dest).trim();
  if (!target) {
    return { ok: false, error: "No backup destination configured" };
  }
  return runManagedFunction({
    kind: "backup-saved-videos",
    queueKey: queueKey === undefined ? SAVED_VIDEOS_QUEUE : queueKey.trim(),
    paths,
    fn: async (onLog, signal) => {
      const result = await backupSavedVideos({
        paths,
        dest: target,
        onLog,
        signal,
      });
      onLog(
        `Saved-video backup: ${result.backedUp}/${result.entries} container(s), ${result.bytes} bytes.`,
      );
      safeRevalidate(["/saved-videos"]);
    },
  });
}

// Verify the backup destination against its manifest and report drift.
export async function verifySavedVideoBackupAction(
  dest?: string,
  queueKey?: string,
): Promise<StreamActionResult> {
  const paths = getPaths();
  const settings = getSettings();
  const target = (dest ?? settings.savedVideoBackup.dest).trim();
  if (!target) {
    return { ok: false, error: "No backup destination configured" };
  }
  return runManagedFunction({
    kind: "verify-saved-video-backup",
    queueKey: queueKey === undefined ? SAVED_VIDEOS_QUEUE : queueKey.trim(),
    paths,
    fn: async (onLog, signal) => {
      const drift = await verifySavedVideoBackup({
        paths,
        dest: target,
        onLog,
        signal,
      });
      onLog(
        drift.ok
          ? `Backup verified clean (checked ${drift.checked}).`
          : `Backup drift: ${drift.missing.length} missing, ${drift.sizeMismatch.length} size-mismatch, ${drift.checksumMismatch.length} checksum-mismatch, ${drift.extra.length} extra.`,
      );
    },
  });
}

// A failure carries what was submitted (lib/formState.ts).
export type SaveBackupConfigResult = FormState;

// Persist just the saved-video backup block (dest / enabled / interval) from the
// Saved Videos page, leaving the rest of SiteSettings untouched. writeSettings
// re-sanitizes (blank dest forces enabled off; interval clamped).
export async function saveSavedVideoBackupAction(
  _prev: SaveBackupConfigResult | undefined,
  formData: FormData,
): Promise<SaveBackupConfigResult> {
  const values = formValues(formData);
  const dest = String(formData.get("backupDest") ?? "").trim();
  const enabled = formData.get("backupEnabled") === "on";
  const intervalRaw = String(formData.get("backupIntervalMinutes") ?? "").trim();
  const intervalMinutes = Number.parseInt(intervalRaw, 10);
  if (intervalRaw && (!Number.isFinite(intervalMinutes) || intervalMinutes < 1)) {
    return {
      ok: false,
      error: `Backup interval must be 1–${SYNC_INTERVAL_MAX_MINUTES} minutes`,
      values,
    };
  }
  const settings = getSettings();
  try {
    await saveSettings({
      savedVideoBackup: {
        enabled,
        dest,
        intervalMinutes: intervalRaw
          ? intervalMinutes
          : settings.savedVideoBackup.intervalMinutes,
      },
    });
  } catch (e) {
    return { ok: false, error: (e as Error).message, values };
  }
  revalidatePath("/saved-videos");
  return { ok: true };
}