src/sub-router/ffmpeg/v2.ts

import { Context, Elysia, t } from "elysia";
import { NS_misc } from "../../lib/misc";
import createError from "http-errors";
import { NS_promise } from "../../lib/promise";
import { NS_ffmpeg_v2 } from "../../lib/ffmpeg-v2";
import { NS_crypto_client } from "../../../../../../packages/lib/helpers/client/crypto";
import { redis } from "../../lib/upstash";
import { offline_store } from "../../lib/offline-store";
import { NS_validator_v2, T_live, T_playback } from "./validator-v2";
import UserAgent from "user-agents";

const APP_ENV = process.env.APP_ENV;
const APP_ACCOUNT_ABC = process.env.APP_ACCOUNT_ABC;

export type T_delivery_payload = {
  playback: T_playback;
  out_mime: "video/mp4" | "video/x-matroska" | "video/mp2t";
  subtitles?: T_live["subtitles"];
  output_destination: NonNullable<T_live["delivery_name"]>;
  delivery_mode: T_live["delivery_mode"];
  delivery_format: T_live["delivery_format"];
  progress_update_endpoint?: T_live["progress_update_endpoint"];
  sbe_id: NonNullable<T_live["sbe_id"]>;
  probe_metadata: Record<string, any>;
};

const sub_router = new Elysia({ prefix: "/ffmpeg/v2" }).post(
  "/probe",
  async (ctx) => {
    const { query, request, status, body } = ctx;

    const REQ0 = new URL(request.url);
    const REQ_ORIGIN = (ctx as any).publicOrigin || REQ0.origin;
    const REQ_headers = request.headers;

    const req0_headers_object = Object.fromEntries(REQ_headers.entries());

    const req_signal = request.signal;

    const { playback, live } = body;

    if (!NS_misc.isValidUrlFormat(playback.url)) {
      if (playback.protocol !== "local") {
        throw createError(400, "invalid playback URL");
      }
    }

    if (
      live?.progress_update_endpoint &&
      !NS_misc.isValidUrlFormat(live.progress_update_endpoint)
    ) {
      throw createError(400, "invalid progress update URL");
    }

    // HANDLE HEADERS
    (() => {
      const playback_headers = playback?.headers;

      if (
        !playback_headers ||
        !(
          typeof playback_headers === "object" &&
          !Array.isArray(playback_headers)
        )
      ) {
        playback.headers = {};
      }

      const ua = NS_misc.F_get_obj_kv({
        name: "User-Agent",
        obj: playback_headers
      });

      if (ua) return;

      try {
        const userAgent =
          UserAgent.random({ deviceCategory: "desktop" }) || new UserAgent();

        if (userAgent?.toString()) {
          (playback.headers as any)["User-Agent"] = userAgent.toString();
        }
      } catch {}
    })();

    // handle picture quality
    (() => {
      if (!playback.picture_quality) {
        return;
      }

      const picture_quality = playback.picture_quality;

      if (
        typeof picture_quality !== "string" ||
        !picture_quality.trim() ||
        picture_quality.trim().toLowerCase() === "n/a"
      ) {
        playback.picture_quality = undefined;
        return;
      }

      playback.picture_quality = picture_quality
        .trim()
        .split(" ")
        .filter((xx) => xx.length)
        .join("");
    })();

    // RUN RAW PROBE
    const [E_, R_] = await NS_promise.F_catch_promise({
      promise: NS_ffmpeg_v2.F_probe_t1({
        context: ctx,
        playback
      })
    });

    // console.error("\n", E_, "\n");

    if (E_) {
      throw E_;
    }

    if (!live) {
      return R_;
    }

    const probe_metadata = R_ as any;

    const clean_metadata = NS_ffmpeg_v2.F_scan_raw_probe_metadata({
      metadata: probe_metadata
    });

    if (clean_metadata?.format) {
      const format_name = clean_metadata.format.name;

      if (typeof format_name === "string" && format_name.includes("hls")) {
        playback.type = "hls";
      } else {
        playback.type = playback.type || "video";
      }
    }

    const subtitles = (() => {
      if (!live.subtitles || !live.subtitles.length) {
        return;
      }

      if (clean_metadata?.subStreams && clean_metadata.subStreams.length) {
        return;
      }

      const original_subs = live.subtitles;

      const filtered = original_subs
        .filter((xx) => {
          return NS_misc.isValidUrlFormat(xx.url);
        })
        .slice(0, 5);

      return filtered;
    })();

    const out_mime: T_delivery_payload["out_mime"] = (() => {
      if (live.delivery_mode === "stream") {
        return "video/mp4";
      }

      switch (live.delivery_format) {
        case "mp4":
          {
            return "video/mp4";
          }

          break;

        case "mkv":
          {
            return "video/x-matroska";
          }

          break;

        case "ts":
          {
            return "video/mp2t";
          }

          break;

        default:
          {
            return "video/mp4";
          }

          break;
      }
    })();

    let output_destination = (
      live.delivery_name ||
      `${live.delivery_mode === "stream" ? "stream" : "video"}-${Date.now()}.${live.delivery_format}`
    ).trim();

    if (
      !output_destination
        .toLowerCase()
        .endsWith(`.${live.delivery_format}`.toLowerCase())
    ) {
      output_destination = `${output_destination}.${live.delivery_format}`;
    }

    if (!live.sbe_id) {
      live.sbe_id = "000000";
    }

    const demand_data = {
      playback,
      out_mime,
      subtitles,
      output_destination,
      delivery_mode: live.delivery_mode,
      delivery_format: live.delivery_format,
      progress_update_endpoint: live.progress_update_endpoint,
      sbe_id: live.sbe_id
    };

    const delivery_payload: T_delivery_payload = {
      ...demand_data,
      probe_metadata
    };

    // store the data in Redis
    const cache_key = await (async () => {
      const cache_id = NS_crypto_client.F_crypto_randomUUID({
        length: 40
      });

      let key = `llsvkm:${cache_id}`;
      if (APP_ACCOUNT_ABC) key = `${key}:${APP_ACCOUNT_ABC}`;

      // 30 days = 30 * 24 * 60 * 60 = 2,592,000 seconds
      const ONE_MONTH_IN_SECONDS = 2592000;

      (delivery_payload as any).cache_id = key;

      if (APP_ENV === "dev") {
        offline_store.set(key, delivery_payload);
      } else {
        await redis.set(key, delivery_payload, { ex: ONE_MONTH_IN_SECONDS });
      }

      return key;
    })();

    const url_o = new URL(`/showtimeV2/delivery/${cache_key}`, REQ_ORIGIN);

    return {
      delivery_endpoint: url_o.toString(),
      metadata: delivery_payload
    };
  },
  {
    body: t.Object({
      playback: NS_validator_v2.playback,
      live: t.Optional(NS_validator_v2.live)
    })
  }
);

export const FfmpegV2Router = sub_router;