/**
 * 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 type {
  IMediaKeys,
  IMediaKeySystemAccess,
} from "../../compat/browser_compatibility_types";
import { EncryptedMediaError, isKnownError } from "../../errors";
import log from "../../log";
import type { IPlayerError } from "../../public_types";
import ServerCertificateStore from "./utils/server_certificate_store";

/**
 * Call the setServerCertificate API with the given certificate.
 * Resolves on success, rejects on failure.
 *
 * TODO Handle returned value?
 * From the spec:
 *   - setServerCertificate resolves with true if everything worked
 *   - it resolves with false if the CDM does not support server
 *     certificates.
 *
 * @param {MediaKeys} mediaKeys
 * @param {ArrayBuffer} serverCertificate
 * @param {MediaKeySystemAccess} mediaKeySystemAccess - The
 * `MediaKeySystemAccess` that produced the `MediaKeys` instance provided.
 * This parameter is mainly useful for error generation.
 * @returns {Promise}
 */
async function setServerCertificate(
  mediaKeys: IMediaKeys,
  serverCertificate: BufferSource,
  mediaKeySystemAccess: IMediaKeySystemAccess,
): Promise<unknown> {
  try {
    const res = await mediaKeys.setServerCertificate(serverCertificate);
    // Note: Even if `setServerCertificate` technically should return a
    // Promise.<boolean>, this is not technically always true.
    // Thus we prefer to return unknown here.
    return res;
  } catch (error) {
    log.warn(
      "DRM",
      "mediaKeys.setServerCertificate returned an error",
      error instanceof Error ? error : "",
    );
    const reason =
      error instanceof Error ? error.toString() : "`setServerCertificate` error";
    throw new EncryptedMediaError("LICENSE_SERVER_CERTIFICATE_ERROR", reason, {
      keyStatuses: undefined,
      keySystemConfiguration: mediaKeySystemAccess.getConfiguration(),
      keySystem: mediaKeySystemAccess.keySystem,
    });
  }
}

/**
 * Call the setCertificate API. If it fails just emit the error as warning
 * and complete.
 * @param {MediaKeys} mediaKeys
 * @param {ArrayBuffer} serverCertificate
 * @param {MediaKeySystemAccess} mediaKeySystemAccess - The
 * `MediaKeySystemAccess` that produced the `MediaKeys` instance provided.
 * This parameter is mainly useful for error generation.
 * @returns {Promise.<Object>}
 */
export default async function trySettingServerCertificate(
  mediaKeys: IMediaKeys,
  serverCertificate: BufferSource,
  mediaKeySystemAccess: IMediaKeySystemAccess,
): Promise<
  | { type: "success"; value: unknown }
  | { type: "already-has-one" }
  | { type: "not-supported" }
  | { type: "method-not-implemented" }
  | { type: "error"; value: IPlayerError }
> {
  if (ServerCertificateStore.hasOne(mediaKeys) === true) {
    log.info("DRM", "The MediaKeys already has a server certificate, skipping...");
    return { type: "already-has-one" };
  }
  if (typeof mediaKeys.setServerCertificate !== "function") {
    log.warn(
      "DRM",
      "Could not set the server certificate." +
        " mediaKeys.setServerCertificate is not a function",
    );
    return { type: "method-not-implemented" };
  }

  log.info("DRM", "Setting server certificate on the MediaKeys");
  // Because of browser errors, or a user action that can lead to interrupting
  // server certificate setting, we might be left in a status where we don't
  // know if we attached the server certificate or not.
  // Calling `prepare` allow to invalidate temporarily that status.
  ServerCertificateStore.prepare(mediaKeys);
  try {
    const result = await setServerCertificate(
      mediaKeys,
      serverCertificate,
      mediaKeySystemAccess,
    );
    if (result === false) {
      log.warn("DRM", "MediaKeys ignored the server certificate. Continuing without it.");
      return { type: "not-supported" };
    }
    ServerCertificateStore.set(mediaKeys, serverCertificate);
    return { type: "success", value: result };
  } catch (error) {
    const formattedErr = isKnownError(error)
      ? error
      : new EncryptedMediaError(
          "LICENSE_SERVER_CERTIFICATE_ERROR",
          "Unknown error when setting the server certificate.",
          {
            keyStatuses: undefined,
            keySystemConfiguration: mediaKeySystemAccess.getConfiguration(),
            keySystem: mediaKeySystemAccess.keySystem,
          },
        );
    return { type: "error" as const, value: formattedErr };
  }
}

export { trySettingServerCertificate, setServerCertificate };