rx-player/src/experimental/tools/mediaCapabilitiesProber/api/probeMediaConfiguration.ts

Canal+ HTML5 Video Player

/**
 * Copyright 2015 CANAL+ Group
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import isNullOrUndefined from "../../../../utils/is_null_or_undefined";
import type { ICapabilitiesTypes } from "../capabilities";
import getProbedConfiguration from "../capabilities";
import log from "../log";
import type { IResultsFromAPI } from "../probers";
import probers from "../probers";
import type { IMediaConfiguration } from "../types";
import { ProberStatus } from "../types";

export type IBrowserAPIS =
  | "isTypeSupported"
  | "isTypeSupportedWithFeatures"
  | "matchMedia"
  | "decodingInfos"
  | "requestMediaKeySystemAccess"
  | "getStatusForPolicy";

export interface IProbedMediaConfiguration {
  globalStatus: ProberStatus;
  resultsFromAPIS: Array<{
    APIName: ICapabilitiesTypes;
    result?: IResultsFromAPI | undefined;
  }>;
}

/**
 * Probe media capabilities, evaluating capabilities with available browsers
 * API.
 *
 * Probe every given features with configuration.
 * If the browser API is not available OR we can't call browser API with enough
 * arguments, do nothing but warn the user (e.g. HDCP is not specified for
 * calling "getStatusForPolicy" API, "mediaCapabilites" API is not available.).
 *
 * From all API results, we return the worst state (e.g. if one API returns a
 * "Not Supported" status among other "Probably" statuses, we return
 * "Not Supported").
 *
 * @param {Object} config
 * @param {Array.<Object>} browserAPIS
 * @returns {Promise}
 */
function probeMediaConfiguration(
  config: IMediaConfiguration,
  browserAPIS: IBrowserAPIS[],
): Promise<IProbedMediaConfiguration> {
  let globalStatus: ProberStatus | undefined;
  const resultsFromAPIS: Array<{
    APIName: ICapabilitiesTypes;
    result: IResultsFromAPI | undefined;
  }> = [];
  const promises = [];
  for (const browserAPI of browserAPIS) {
    const probeWithBrowser = probers[browserAPI];
    if (probeWithBrowser !== undefined) {
      const prom = probeWithBrowser(config)
        .then(([currentStatus, result]) => {
          resultsFromAPIS.push({ APIName: browserAPI, result });

          if (isNullOrUndefined(globalStatus)) {
            globalStatus = currentStatus;
          } else {
            switch (currentStatus) {
              // Here, globalStatus can't be null. Hence, if the new current status is
              // 'worse' than global status, then re-assign the latter.
              case ProberStatus.NotSupported:
                // `NotSupported` is either worse or equal.
                globalStatus = ProberStatus.NotSupported;
                break;
              case ProberStatus.Unknown:
                // `Unknown` is worse than 'Supported' only.
                if (globalStatus === ProberStatus.Supported) {
                  globalStatus = ProberStatus.Unknown;
                }
                break;
              default:
                // new status is either `Supported` or unknown status. Global status
                // shouldn't be changed.
                break;
            }
          }
        })
        .catch((error: unknown) => {
          if (error instanceof Error) {
            log.debug(error.message);
          }
        });
      promises.push(prom);
    }
  }

  return Promise.all(promises).then(() => {
    if (globalStatus === undefined) {
      globalStatus = ProberStatus.Unknown;
    }

    const probedCapabilities = getProbedConfiguration(
      config,
      resultsFromAPIS.map((a) => a.APIName),
    );
    const areUnprobedCapabilities =
      JSON.stringify(probedCapabilities).length !== JSON.stringify(config).length;

    if (areUnprobedCapabilities && globalStatus === ProberStatus.Supported) {
      globalStatus = ProberStatus.Unknown;
    }

    if (areUnprobedCapabilities) {
      log.warn(
        "MediaCapabilitiesProber >>> PROBER: Some capabilities " +
          "could not be probed, due to the incompatibility of browser APIs, or the " +
          "lack of arguments to call them. See debug logs for more details.",
      );
    }

    if (log.hasLevel("INFO")) {
      log.info(
        "MediaCapabilitiesProber >>> PROBER: Probed capabilities: ",
        JSON.stringify(probedCapabilities),
      );
    }

    return { globalStatus, resultsFromAPIS };
  });
}

export default probeMediaConfiguration;