import { NextResponse } from "next/server";
import { keepVideosAction } from "../../../channels/[slug]/videos/[id]/videoActions";
import { OpsInputError, ops, optBool, optString, opsFail, reqSlug, reqString } from "../_lib";

export const dynamic = "force-dynamic";

// POST { slug, match, fields?: ("title"|"description")[], note?, dryRun? }
//   -> { ok: true, pattern, fields, considered, matched: [{ id, title,
//        downloaded, alreadyKept, marked }], marked, alreadyKept,
//        notDownloaded, unscanned, noMetadata, dryRun }
//
// AN ADAPTER: one call to keepVideosAction, the bulk form of the video page's
// "Do not clean" toggle. It writes the same per-video do-not-clean.json marker
// every cleaner already honours; it adds no protection of its own.
//
// `match` IS A DOWNLOAD-FILTER PATTERN, matched the way the filter matches it —
// a case-insensitive regex SOURCE over title + "\n" + description, compiled by
// the same function. A pattern that keeps the right videos here would download
// the right ones as a channel's `downloadFilterInclude`. `fields` narrows the
// subject to one half.
//
// A MATCH WITH NO data/<id>/ IS REPORTED, NOT CREATED. The marker lives in the
// video's dir, and a dir is what every enumerator reads as "fetched". Those ids
// come back in `notDownloaded`: send them to `download-missing`, then run this
// again. A fresh channel wants `metadata-scan` FIRST — an id with no dir and no
// scan entry has no text to match, and is only counted (`unscanned`).
//
// `dryRun: true` answers the same question and writes nothing.
export async function POST(request: Request) {
  return ops(request, ["slug", "match", "fields", "note", "dryRun"], async (body) => {
    const slug = reqSlug(body, "slug");
    const pattern = reqString(body, "match");
    const raw = body.fields;
    let fields: ("title" | "description")[] | undefined;
    if (raw !== undefined) {
      if (
        !Array.isArray(raw) ||
        raw.length === 0 ||
        raw.some((f) => f !== "title" && f !== "description")
      ) {
        throw new OpsInputError(
          '"fields" must be a non-empty array of "title" and/or "description"',
        );
      }
      fields = raw as ("title" | "description")[];
    }
    const result = await keepVideosAction({
      slug,
      pattern,
      fields,
      note: optString(body, "note"),
      dryRun: optBool(body, "dryRun"),
    });
    if (!result.ok) return opsFail(result.error);
    return NextResponse.json({ ok: true, ...result.result });
  });
}