/**
 * 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 arrayFind from "../../../utils/array_find";
import isNullOrUndefined from "../../../utils/is_null_or_undefined";
import type { IMediaConfiguration } from "./types";

export type ICapabilities = Array<string | { [key: string]: ICapabilities }>;

/**
 * Extends a capabilities array with others.
 * @param {Array<Object>} target
 * @param {Array<Object>} objects
 * @returns {Array.<Object>}
 */
export function extend(target: ICapabilities, objects: ICapabilities[]): ICapabilities {
  objects.forEach((obj) => {
    obj.forEach((element) => {
      if (typeof element === "string") {
        if (
          arrayFind(target, (targetElement) => targetElement === element) === undefined
        ) {
          target.push(element);
        }
      } else {
        const entry = Object.entries(element)[0];
        const [key, value] = entry;
        const foundTargetElement = arrayFind(
          target,
          (targetElement) =>
            typeof targetElement !== "string" &&
            targetElement[key] !== undefined &&
            targetElement[key].length > 0,
        ) as undefined | { [key: string]: ICapabilities };
        if (foundTargetElement === undefined) {
          const toPush: { [key: string]: ICapabilities } = {};
          toPush[key] = extend([], [value]);
          target.push(toPush);
        } else {
          const targetElementToExtend: {
            [key: string]: ICapabilities;
          } = foundTargetElement;
          targetElementToExtend[key] = extend(targetElementToExtend[key], [value]);
        }
      }
    });
  });
  return target;
}

/**
 * From input config object and probed capabilities, create
 * probed configuration object.
 * @param {Array<Object>} capabilities
 * @param {Object} configuration
 * @returns {Object}
 */
export function filterConfigurationWithCapabilities(
  capabilities: ICapabilities,
  configuration: IMediaConfiguration,
): IMediaConfiguration {
  const probedConfig = {};

  capabilities.forEach((capability) => {
    if (typeof capability === "string") {
      if (
        (
          configuration as {
            [id: string]: string | IMediaConfiguration;
          }
        )[capability] !== undefined
      ) {
        // eslint-disable-next-line @typescript-eslint/no-unnecessary-type-assertion
        (probedConfig as { [id: string]: string | IMediaConfiguration })[capability] = (
          configuration as { [id: string]: string | IMediaConfiguration }
        )[capability];
      }
    } else {
      const [key, value] = Object.entries(capability)[0];
      const newConfiguration =
        (configuration as { [id: string]: IMediaConfiguration })[key] === undefined
          ? {}
          : (configuration as { [id: string]: IMediaConfiguration })[key];
      const subProbedConfig = filterConfigurationWithCapabilities(
        value,
        newConfiguration,
      );
      if (
        Object.keys(subProbedConfig).length > 0 ||
        (!isNullOrUndefined(
          (configuration as { [id: string]: IMediaConfiguration })[key],
        ) &&
          Object.keys((configuration as { [id: string]: IMediaConfiguration })[key])
            .length === 0)
      ) {
        // eslint-disable-next-line @typescript-eslint/no-unnecessary-type-assertion
        (probedConfig as { [id: string]: IMediaConfiguration })[key] = subProbedConfig;
      }
    }
  });

  return probedConfig;
}