/**
 * Copyright 2024-2026 Wingify Software Pvt. Ltd.
 *
 * 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 { Storage } from './packages/storage';

import { Flag, FlagApi } from './api/GetFlag';
import { SetAttributeApi } from './api/SetAttribute';
import { TrackApi } from './api/TrackEvent';

import { DebugLogMessagesEnum, InfoLogMessagesEnum, ErrorLogMessagesEnum } from './enums/log-messages';
import { SettingsModel } from './models/settings/SettingsModel';

import { dynamic } from './types/Common';
import { SettingsSchema } from './models/schemas/SettingsSchemaValidation';
import { ContextModel } from './models/user/ContextModel';

import { getType, isObject, isString, isBoolean, isNumber } from './utils/DataTypeUtil';

import { buildMessage } from './utils/LogMessageUtil';
import { Deferred } from './utils/PromiseUtil';

import { IWingifyOptions } from './models/WingifyOptionsModel';
import { setSettingsAndAddCampaignsToRules } from './utils/SettingsUtil';
import { VariationModel } from './models/campaign/VariationModel';
import { ApiEnum } from './enums/ApiEnum';
import { AliasingUtil } from './utils/AliasingUtil';
import { getUserId } from './utils/UserIdUtil';
import { isArray } from './utils/DataTypeUtil';
import { getCurrentUnixTimestamp, getFormattedErrorMessage } from './utils/FunctionUtil';
import { ServiceContainer } from './services/ServiceContainer';
import { sendSdkInitEvent, sendSDKUsageStatsEvent } from './utils/SdkInitAndUsageStatsUtil';
import { UsageStatsUtil } from './utils/UsageStatsUtil';
import { StorageService } from './services/StorageService';
import { getUUID, isWebUuid } from './utils/UuidUtil';
import { SDKMetaUtil } from './utils/SDKMetaUtil';

export interface IWingifyClient {
  readonly options?: IWingifyOptions;
  settings: SettingsModel;
  originalSettings: Record<any, any>;
  isSettingsValid: boolean;
  settingsFetchTime: number | undefined;
  isAliasingEnabled: boolean;

  getFlag(featureKey: string, context: Record<string, any>): Promise<Flag>;
  trackEvent(
    eventName: string,
    context: Record<string, any>,
    eventProperties?: Record<string, dynamic>,
  ): Promise<Record<string, boolean>>;
  setAttribute(
    attributeKey: string,
    attributeValue: boolean | string | number,
    context: Record<string, any>,
  ): Promise<void>;
  setAttribute(attributes: Record<string, boolean | string | number>, context: Record<string, any>): Promise<void>;
  updateSettings(settings?: Record<string, any>, isViaWebhook?: boolean): Promise<void>;
  flushEvents(): Promise<Record<string, any>>;
  shutdown(): Promise<void>;
  setAlias(context: Record<string, any> | string, aliasId: string): Promise<boolean>;
}

export class WingifyClient implements IWingifyClient {
  settings: SettingsModel;
  originalSettings: Record<any, any>;
  storage: Storage;
  wingifyClientInstance: WingifyClient;
  isSettingsValid: boolean;
  settingsFetchTime: number | undefined;
  isAliasingEnabled: boolean;
  serviceContainer: ServiceContainer;
  options?: IWingifyOptions;
  private isShutdown: boolean = false;

  /**
   * Constructor for the WingifyClient class.
   * @param settings - The settings to initialize the client with.
   * @param options - The options to initialize the client with.
   * @param logManager - The log manager to use for logging.
   * @param settingsService - The settings service to use for fetching settings.
   * @param networkManager - The network manager to use for making network requests.
   * @param storage - The storage to use for storing data.
   * @param batchEventsQueue - The batch events queue to use for batching events.
   */
  constructor(settings: Record<any, any>, options: IWingifyOptions, serviceContainer: ServiceContainer) {
    try {
      this.options = options;
      this.serviceContainer = serviceContainer;
      this.isSettingsValid = new SettingsSchema().isSettingsValid(settings);
      this.isAliasingEnabled = options.isAliasingEnabled || false;
      if (this.isSettingsValid && !this.serviceContainer.getSettingsService().isSettingsProvidedInInit) {
        this.serviceContainer.getLogManager().info(buildMessage(InfoLogMessagesEnum.SETTINGS_FETCH_SUCCESS));
      } else if (!this.isSettingsValid && this.options.settings) {
        this.serviceContainer.getLogManager().errorLog('INVALID_SETTINGS_SCHEMA', {}, { an: ApiEnum.INIT }, false);
      }
      setSettingsAndAddCampaignsToRules(settings, this, this.serviceContainer.getLogManager());
      this.serviceContainer.setSettings(this.settings);
      this.serviceContainer.injectServiceContainer(this.serviceContainer);
      this.serviceContainer.setShouldWaitForTrackingCalls(this.options.shouldWaitForTrackingCalls || false);

      this.serviceContainer.getLogManager().info(buildMessage(InfoLogMessagesEnum.CLIENT_INITIALIZED));
      this.wingifyClientInstance = this;
      const usageStatsUtil = new UsageStatsUtil(this.options);
      this.sendSdkInitAndUsageStatsEvents(usageStatsUtil);
      // initialize the sdk meta util
      new SDKMetaUtil(this.options);
      return this;
    } catch (err) {
      this.serviceContainer.getLogManager().errorLog(
        'EXECUTION_FAILED',
        {
          apiName: ApiEnum.INIT,
          err: getFormattedErrorMessage(err),
        },
        { an: ApiEnum.INIT },
        false,
      );
    }
  }

  /**
   * Sends the SDK init event and usage stats event
   * @param usageStatsUtil - The usage stats util to use for sending the usage stats event
   */
  private async sendSdkInitAndUsageStatsEvents(usageStatsUtil: UsageStatsUtil) {
    try {
      // get settings fetch time
      let settingsFetchTime = this.serviceContainer.getSettingsService().settingsFetchTime;
      if (this.serviceContainer.getSettingsService().isSettingsProvidedInInit) {
        // if settings are provided in init, then settings fetch time is 0
        settingsFetchTime = 0;
      }
      // get sdk init time
      const sdkInitTime = Date.now() - this.serviceContainer.getSettingsService().startTimeForInit;
      // if settings are valid and was initialized earlier is false, then send sdk init event
      if (this.isSettingsValid && !this.originalSettings?.sdkMetaInfo?.wasInitializedEarlier) {
        // if shouldWaitForTrackingCalls is true, then wait for sendSdkInitEvent to complete
        if (this.options.shouldWaitForTrackingCalls) {
          await sendSdkInitEvent(settingsFetchTime, sdkInitTime, this.serviceContainer);
        } else {
          // send sdk init event
          sendSdkInitEvent(settingsFetchTime, sdkInitTime, this.serviceContainer);
        }
      }

      // send sdk usage stats event
      const usageStatsAccountId = this.originalSettings?.usageStatsAccountId;
      if (usageStatsAccountId) {
        if (this.options.shouldWaitForTrackingCalls) {
          await sendSDKUsageStatsEvent(usageStatsAccountId, this.serviceContainer, usageStatsUtil);
        } else {
          sendSDKUsageStatsEvent(usageStatsAccountId, this.serviceContainer, usageStatsUtil);
        }
      }
    } catch (err) {
      this.serviceContainer
        .getLogManager()
        .error(buildMessage(ErrorLogMessagesEnum.SDK_INIT_EVENT_FAILED, { err: getFormattedErrorMessage(err) }));
    }
  }

  /**
   * Retrieves the value of a feature flag for a given feature key and context.
   * This method validates the feature key and context, ensures the settings are valid, and then uses the FlagApi to get the flag value.
   *
   * @param {string} featureKey - The key of the feature to retrieve.
   * @param {ContextModel} context - The context in which the feature flag is being retrieved, must include a valid user ID.
   * @returns {Promise<Flag>} - A promise that resolves to the feature flag value.
   */
  async getFlag(featureKey: string, context: Record<string, any>): Promise<Flag> {
    const apiName = ApiEnum.GET_FLAG;
    const deferredObject = new Deferred();
    let uuid: string;
    try {
      this.serviceContainer.getLogManager().debug(
        buildMessage(DebugLogMessagesEnum.API_CALLED, {
          apiName,
        }),
      );
      // get uuid from context
      uuid = this.getUUIDFromContext(context, apiName);
    } catch (err) {
      this.serviceContainer.getLogManager().errorLog(
        'EXECUTION_FAILED',
        {
          apiName,
          err: getFormattedErrorMessage(err),
        },
        { an: ApiEnum.GET_FLAG },
      );
      // return error return schema with null uuid
      deferredObject.resolve(
        new Flag(false, context?.sessionId ?? getCurrentUnixTimestamp(), null, new VariationModel()),
      );
      return deferredObject.promise;
    }
    const errorReturnSchema = new Flag(
      false,
      context?.sessionId ?? getCurrentUnixTimestamp(),
      uuid,
      new VariationModel(),
    );

    try {
      // Validate featureKey is a string
      if (!isString(featureKey)) {
        this.serviceContainer.getLogManager().errorLog(
          'INVALID_PARAM',
          {
            apiName,
            key: 'featureKey',
            type: getType(featureKey),
            correctType: 'string',
          },
          { an: ApiEnum.GET_FLAG },
          false,
        );

        throw new TypeError('TypeError: featureKey should be a string, got ' + getType(featureKey));
      }

      // Validate settings are loaded and valid
      if (!this.isSettingsValid) {
        this.serviceContainer.getLogManager().errorLog('INVALID_SETTINGS_SCHEMA', {}, { an: ApiEnum.GET_FLAG }, false);
        throw new Error('TypeError: Invalid Settings');
      }

      // Validate user ID is present in context
      if (!context || !context.id) {
        this.serviceContainer.getLogManager().errorLog('INVALID_CONTEXT_PASSED', {}, { an: ApiEnum.GET_FLAG }, false);
        throw new TypeError('TypeError: Invalid context');
      }

      //getUserId from gateway service
      const userId = await getUserId(context.id, this.isAliasingEnabled, this.serviceContainer);
      // Create a copy of context to avoid modifying the original
      const contextCopy = { ...context };
      contextCopy.id = userId;

      // check if the userId changed after aliasing, by comparing the original userId with the new userId
      if (contextCopy.id !== context.id) {
        // if the userId changed, then we need to generate a new uuid
        contextCopy.uuid = this.getUUIDFromContext(contextCopy, apiName);
      } else {
        // if the userId didn't change, then we can use the existing uuid
        contextCopy.uuid = uuid;
      }

      // Validate bucketingSeed: must be a non-empty, non-whitespace-only string
      if ('bucketingSeed' in contextCopy) {
        const seed = contextCopy.bucketingSeed;
        if (
          seed === undefined ||
          seed === null ||
          isNumber(seed) ||
          isObject(seed) ||
          isArray(seed) ||
          (isString(seed) && (seed as string).trim().length === 0)
        ) {
          this.serviceContainer.getLogManager().errorLog(
            'INVALID_BUCKETING_SEED',
            {
              apiName,
              type: getType(seed),
            },
            { an: ApiEnum.GET_FLAG },
            false,
          );
          delete contextCopy.bucketingSeed;
        }
      }

      const contextModel = new ContextModel().modelFromDictionary(contextCopy, this.options);

      FlagApi.get(featureKey, contextModel, this.serviceContainer)
        .then((data) => {
          deferredObject.resolve(data);
        })
        .catch(() => {
          deferredObject.resolve(errorReturnSchema);
        });
    } catch (err) {
      this.serviceContainer.getLogManager().errorLog(
        'EXECUTION_FAILED',
        {
          apiName,
          err: getFormattedErrorMessage(err),
        },
        { an: ApiEnum.GET_FLAG },
      );

      deferredObject.resolve(errorReturnSchema);
    }

    return deferredObject.promise;
  }

  /**
   * Tracks an event with specified properties and context.
   * This method validates the types of the inputs and ensures the settings and user context are valid before proceeding.
   *
   * @param {string} eventName - The name of the event to track.
   * @param {ContextModel} context - The context in which the event is being tracked, must include a valid user ID.
   * @param {Record<string, dynamic>} eventProperties - The properties associated with the event.
   * @returns {Promise<Record<string, boolean>>} - A promise that resolves to the result of the tracking operation.
   */
  async trackEvent(
    eventName: string,
    context: Record<string, any>,
    eventProperties: Record<string, dynamic> = {},
  ): Promise<Record<string, boolean>> {
    const apiName = ApiEnum.TRACK_EVENT;
    const deferredObject = new Deferred();

    try {
      // Log the API call
      this.serviceContainer.getLogManager().debug(
        buildMessage(DebugLogMessagesEnum.API_CALLED, {
          apiName,
        }),
      );

      // Validate eventName is a string
      if (!isString(eventName)) {
        this.serviceContainer.getLogManager().errorLog(
          'INVALID_PARAM',
          {
            apiName,
            key: 'eventName',
            type: getType(eventName),
            correctType: 'string',
          },
          { an: ApiEnum.TRACK_EVENT },
          false,
        );

        throw new TypeError('TypeError: Event-name should be a string, got ' + getType(eventName));
      }

      // Validate eventProperties is an object
      if (!isObject(eventProperties)) {
        this.serviceContainer.getLogManager().errorLog(
          'INVALID_PARAM',
          {
            apiName,
            key: 'eventProperties',
            type: getType(eventProperties),
            correctType: 'object',
          },
          { an: ApiEnum.TRACK_EVENT },
          false,
        );

        throw new TypeError('TypeError: eventProperties should be an object, got ' + getType(eventProperties));
      }

      // Validate settings are loaded and valid
      if (!this.isSettingsValid) {
        this.serviceContainer
          .getLogManager()
          .errorLog('INVALID_SETTINGS_SCHEMA', {}, { an: ApiEnum.TRACK_EVENT }, false);
        throw new Error('TypeError: Invalid Settings');
      }

      // Validate user ID is present in context
      if (!context || !context.id) {
        this.serviceContainer
          .getLogManager()
          .errorLog('INVALID_CONTEXT_PASSED', {}, { an: ApiEnum.TRACK_EVENT }, false);
        throw new TypeError('TypeError: Invalid context');
      }

      //getUserId from gateway service
      const userId = await getUserId(context.id, this.isAliasingEnabled, this.serviceContainer);
      // Create a copy of context to avoid modifying the original
      const contextCopy = { ...context };
      contextCopy.id = userId;
      // set uuid in the context copy
      contextCopy.uuid = this.getUUIDFromContext(contextCopy, apiName);

      const contextModel = new ContextModel().modelFromDictionary(contextCopy, this.options);

      // Proceed with tracking the event
      new TrackApi()
        .track(this.serviceContainer, eventName, contextModel, eventProperties)
        .then((data) => {
          deferredObject.resolve(data);
        })
        .catch(() => {
          deferredObject.resolve({ [eventName]: false });
        });
    } catch (err) {
      // Log any errors encountered during the operation
      this.serviceContainer.getLogManager().errorLog(
        'EXECUTION_FAILED',
        {
          apiName,
          err: getFormattedErrorMessage(err),
        },
        { an: ApiEnum.TRACK_EVENT },
      );

      deferredObject.resolve({ [eventName]: false });
    }

    return deferredObject.promise;
  }

  /**
   * Sets an attribute or multiple attributes for a user in the provided context.
   * This method validates the types of the inputs before proceeding with the API call.
   * There are two cases handled:
   * 1. When attributes are passed as a map (key-value pairs).
   * 2. When a single attribute (key-value) is passed.
   *
   * @param {string | Record<string, boolean | string | number>} attributeOrAttributes - Either a single attribute key (string) and value (boolean | string | number),
   *                                                                                        or a map of attributes with keys and values (boolean | string | number).
   * @param {boolean | string | number | Record<string, any>} [attributeValueOrContext] - The value for the attribute in case of a single attribute, or the context when multiple attributes are passed.
   * @param {Record<string, any>} [context] - The context which must include a valid user ID. This is required if multiple attributes are passed.
   */
  async setAttribute(
    attributeOrAttributes: string | Record<string, boolean | string | number>,
    attributeValueOrContext?: boolean | string | number | Record<string, any>,
    context?: Record<string, any>,
  ): Promise<void> {
    const apiName = ApiEnum.SET_ATTRIBUTE;

    try {
      if (isObject(attributeOrAttributes)) {
        // Log the API call
        this.serviceContainer.getLogManager().debug(
          buildMessage(DebugLogMessagesEnum.API_CALLED, {
            apiName,
          }),
        );

        if (Object.entries(attributeOrAttributes).length < 1) {
          throw new TypeError('TypeError: Attributes should be an object containing at least 1 key-value pair');
        }

        // Case where multiple attributes are passed as a map
        const attributes = attributeOrAttributes as Record<string, boolean | string | number>; // Type assertion

        // Validate attributes is an object
        if (!isObject(attributes)) {
          throw new TypeError('TypeError: attributes should be an object containing key-value pairs');
        }

        // Validate that each attribute value is of a supported type
        Object.entries(attributes).forEach(([key, value]) => {
          if (typeof value !== 'boolean' && typeof value !== 'string' && typeof value !== 'number') {
            throw new TypeError(
              `Invalid attribute type for key "${key}". Expected boolean, string or number, but got ${getType(value)}`,
            );
          }

          // Reject arrays and objects explicitly
          if (Array.isArray(value) || (typeof value === 'object' && value !== null)) {
            throw new TypeError(`Invalid attribute value for key "${key}". Arrays and objects are not supported.`);
          }
        });

        // If we have only two arguments (attributeMap and context)
        if (!context && attributeValueOrContext) {
          context = attributeValueOrContext as Record<string, any>; // Assign context explicitly
        }

        // Validate user ID is present in context
        if (!context || !context.id) {
          this.serviceContainer
            .getLogManager()
            .errorLog('INVALID_CONTEXT_PASSED', {}, { an: ApiEnum.SET_ATTRIBUTE }, false);
          throw new TypeError('TypeError: Invalid context');
        }

        //getUserId from gateway service
        const userId = await getUserId(context.id, this.isAliasingEnabled, this.serviceContainer);
        // Create a copy of context to avoid modifying the original
        const contextCopy = { ...context };
        contextCopy.id = userId;
        // set uuid in the context copy
        contextCopy.uuid = this.getUUIDFromContext(contextCopy, apiName);

        const contextModel = new ContextModel().modelFromDictionary(contextCopy, this.options);
        // Proceed with setting the attributes if validation is successful
        await new SetAttributeApi().setAttribute(this.serviceContainer, attributes, contextModel);
      } else {
        // Case where a single attribute (key-value) is passed
        const attributeKey = attributeOrAttributes;
        const attributeValue = attributeValueOrContext;

        // Validate attributeKey is a string
        if (!isString(attributeKey)) {
          throw new TypeError('attributeKey should be a string');
        }

        // Validate attributeValue is of valid type
        if (!isBoolean(attributeValue) && !isString(attributeValue) && !isNumber(attributeValue)) {
          throw new TypeError('attributeValue should be a boolean, string, or number');
        }

        // Validate user ID is present in context
        if (!context || !context.id) {
          throw new TypeError('Invalid context');
        }

        //getUserId from gateway service
        const userId = await getUserId(context.id, this.isAliasingEnabled, this.serviceContainer);
        // Create a copy of context to avoid modifying the original
        const contextCopy = { ...context };
        contextCopy.id = userId;

        const contextModel = new ContextModel().modelFromDictionary(contextCopy, this.options);

        // Create a map from the single attribute key-value pair
        const attributeMap = { [attributeKey]: attributeValue };

        // Proceed with setting the attribute map if validation is successful
        await new SetAttributeApi().setAttribute(this.serviceContainer, attributeMap, contextModel);
      }
    } catch (err) {
      this.serviceContainer.getLogManager().errorLog(
        'EXECUTION_FAILED',
        {
          apiName,
          err: getFormattedErrorMessage(err),
        },
        { an: ApiEnum.SET_ATTRIBUTE },
      );
    }
  }

  /**
   * Updates the settings by fetching the latest settings from the Wingify server.
   * @param settings - The settings to update.
   * @param isViaWebhook - Whether to fetch the settings from the webhook endpoint.
   * @returns Promise<void>
   */
  async updateSettings(settings?: Record<string, any>, isViaWebhook = true): Promise<void> {
    const apiName = ApiEnum.UPDATE_SETTINGS;
    try {
      this.serviceContainer.getLogManager().debug(buildMessage(DebugLogMessagesEnum.API_CALLED, { apiName }));
      // fetch settings from the server or use the provided settings file if it's not empty
      const settingsToUpdate =
        !settings || Object.keys(settings).length === 0
          ? await this.serviceContainer.getSettingsService().fetchSettings(isViaWebhook, apiName)
          : settings;

      const normalizedSettings = this.serviceContainer.getSettingsService().normalizeSettings(settingsToUpdate);
      // validate settings schema
      if (!new SettingsSchema().isSettingsValid(normalizedSettings)) {
        throw new Error('TypeError: Invalid Settings schema');
      }

      // set the settings on the client instance
      setSettingsAndAddCampaignsToRules(
        normalizedSettings,
        this.wingifyClientInstance,
        this.serviceContainer.getLogManager(),
      );
      this.serviceContainer.setSettings(this.wingifyClientInstance.settings);
      this.serviceContainer.injectServiceContainer(this.serviceContainer);
      this.serviceContainer
        .getLogManager()
        .info(buildMessage(InfoLogMessagesEnum.SETTINGS_UPDATED, { apiName, isViaWebhook }));
    } catch (err) {
      this.serviceContainer.getLogManager().errorLog(
        'UPDATING_CLIENT_INSTANCE_FAILED_WHEN_WEBHOOK_TRIGGERED',
        {
          apiName,
          isViaWebhook,
          err: getFormattedErrorMessage(err),
        },
        { an: ApiEnum.UPDATE_SETTINGS },
      );
    }
  }

  /**
   * Flushes the events manually from the batch events queue
   */
  async flushEvents(): Promise<Record<string, any>> {
    const apiName = ApiEnum.FLUSH_EVENTS;

    try {
      this.serviceContainer.getLogManager().debug(buildMessage(DebugLogMessagesEnum.API_CALLED, { apiName }));

      if (!this.serviceContainer.getBatchEventsQueue()) {
        this.serviceContainer.getLogManager().errorLog('BATCHING_NOT_ENABLED', {}, { an: ApiEnum.FLUSH_EVENTS });
        return { status: 'error', events: [] };
      }

      const promises: Promise<any>[] = [this.serviceContainer.getBatchEventsQueue().flushAndClearTimer()];

      if (
        this.options?.edgeConfig &&
        Object.keys(this.options.edgeConfig).length > 0 &&
        this.options?.accountId &&
        this.options?.sdkKey
      ) {
        const storageService = new StorageService(this.serviceContainer);
        promises.push(
          storageService
            .setFreshSettingsInStorage(parseInt(this.options.accountId), this.options.sdkKey)
            .catch((error) => {
              this.serviceContainer
                .getLogManager()
                .errorLog(
                  'ERROR_STORING_SETTINGS_IN_STORAGE',
                  { err: getFormattedErrorMessage(error) },
                  { an: ApiEnum.FLUSH_EVENTS },
                );
              // by returning undefined, we are swallowing the error intentionally to avoid the promise from rejecting
              return undefined;
            }),
        );
      }

      const [flushResult] = await Promise.all(promises);
      return flushResult;
    } catch (err) {
      this.serviceContainer
        .getLogManager()
        .errorLog('EXECUTION_FAILED', { apiName, err: getFormattedErrorMessage(err) }, { an: ApiEnum.FLUSH_EVENTS });
      return { status: 'error', events: [] };
    }
  }

  /**
   * Sets alias for a given user ID
   * @param contextOrUserId - The context containing user ID or the user ID directly
   * @param aliasId - The alias identifier to set
   * @returns Promise<boolean> - Returns true if successful, false otherwise
   */
  async setAlias(contextOrUserId: Record<string, any> | string, aliasId: string): Promise<boolean> {
    const apiName = ApiEnum.SET_ALIAS;
    try {
      this.serviceContainer.getLogManager().debug(
        buildMessage(DebugLogMessagesEnum.API_CALLED, {
          apiName,
        }),
      );

      if (!this.isAliasingEnabled) {
        this.serviceContainer.getLogManager().errorLog('ALIAS_CALLED_BUT_NOT_PASSED', {}, { an: ApiEnum.SET_ALIAS });
        return false;
      }

      if (!this.serviceContainer.getSettingsService().isGatewayServiceProvided) {
        this.serviceContainer.getLogManager().errorLog('INVALID_GATEWAY_URL', {}, { an: ApiEnum.SET_ALIAS });
        return false;
      }

      if (!aliasId) {
        throw new TypeError('TypeError: Invalid aliasId');
      }

      if (isArray(aliasId)) {
        throw new TypeError('TypeError: aliasId cannot be an array');
      }

      // trim aliasId before going forward
      aliasId = aliasId.trim();

      let userId: string;

      if (typeof contextOrUserId === 'string') {
        // trim contextOrUserId before going forward
        contextOrUserId = contextOrUserId.trim();

        // Direct userId provided
        if (contextOrUserId === aliasId) {
          throw new TypeError('UserId and aliasId cannot be the same.');
        }

        if (!contextOrUserId) {
          throw new TypeError('TypeError: Invalid userId');
        }

        if (isArray(contextOrUserId)) {
          throw new TypeError('TypeError: userId cannot be an array');
        }

        userId = contextOrUserId;
      } else {
        // Context object provided
        if (!contextOrUserId || !contextOrUserId.id) {
          throw new TypeError('TypeError: Invalid context');
        }

        if (isArray(contextOrUserId.id)) {
          throw new TypeError('TypeError: context.id cannot be an array');
        }

        // trim contextOrUserId.id before going forward
        contextOrUserId.id = contextOrUserId.id.trim();

        if (contextOrUserId.id === aliasId) {
          throw new TypeError('UserId and aliasId cannot be the same.');
        }
        userId = contextOrUserId.id;
      }

      await AliasingUtil.setAlias(userId, aliasId, this.serviceContainer);
      return true;
    } catch (error) {
      this.serviceContainer
        .getLogManager()
        .errorLog('EXECUTION_FAILED', { apiName, err: getFormattedErrorMessage(error) }, { an: ApiEnum.SET_ALIAS });
      return false;
    }
  }

  /**
   * Generates a UUID from the context.id
   * @param context - The context to generate the UUID from
   * @param apiName - The name of the API calling this method
   * @returns The UUID generated from the context.id
   */
  private getUUIDFromContext(context: Record<string, any>, apiName: string): string {
    if (this.settings.getIsWebConnectivityEnabled() !== false) {
      // if web connectivity is enabled, check if context.id is a valid web UUID
      if (isWebUuid(context?.id)) {
        // if context.id is a valid web UUID, set it as uuid
        this.serviceContainer.getLogManager().debug(
          buildMessage(DebugLogMessagesEnum.WEB_UUID_FOUND, {
            apiName,
            uuid: context.id,
          }),
        );
        return context.id;
      } else {
        // if context?.useIdForWeb is true and context.id is not a valid web UUID, throw error
        if (context?.useIdForWeb === true) {
          throw new Error('UUID passed in context.id is not a valid UUID');
        }
        // if context?.useIdForWeb is false, fallback to server‑side UUID derivation
        return getUUID(
          context?.id?.toString() ?? `${this.options?.accountId}_${this.options?.sdkKey}`,
          this.options?.accountId?.toString(),
        );
      }
    } else {
      // if web connectivity is disabled, fallback to server‑side UUID derivation
      return getUUID(
        context?.id?.toString() ?? `${this.options?.accountId}_${this.options?.sdkKey}`,
        this.options?.accountId?.toString(),
      );
    }
  }

  /**
   * Shuts down the client: flushes pending batch events (and clears the batch timer) via flushEvents(),
   * then clears the batch queue so no further events are enqueued. Idempotent.
   */
  async shutdown(): Promise<void> {
    try {
      this.serviceContainer
        .getLogManager()
        .debug(buildMessage(DebugLogMessagesEnum.API_CALLED, { apiName: ApiEnum.SHUTDOWN }));
      // check if the client is already shutdown
      if (this.isShutdown) {
        this.serviceContainer.getLogManager().info(buildMessage(InfoLogMessagesEnum.SHUTDOWN_ALREADY_COMPLETED));
        return;
      }
      // set the isShutdown flag to true to avoid multiple calls to shutdown
      this.isShutdown = true;
      this.serviceContainer.stopPolling();
      if (this.serviceContainer.getBatchEventsQueue()) {
        await this.flushEvents();
        this.serviceContainer.getLogManager().info(buildMessage(InfoLogMessagesEnum.SHUTDOWN_COMPLETED_WITH_FLUSH));
        this.serviceContainer.setBatchEventsQueue(null);
      } else {
        this.serviceContainer.getLogManager().info(buildMessage(InfoLogMessagesEnum.SHUTDOWN_COMPLETED_WITHOUT_FLUSH));
      }
    } catch (err) {
      this.serviceContainer
        .getLogManager()
        .errorLog(
          'EXECUTION_FAILED',
          { apiName: ApiEnum.SHUTDOWN, err: getFormattedErrorMessage(err) },
          { an: ApiEnum.SHUTDOWN },
        );
    }
  }
}