/*
 * Copyright 2020 The Backstage Authors
 *
 * 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.
 */

export interface Config {
  app: {
    // TODO: Only marked as optional because backstage-cli config:check in the
    // context of the monorepo is too strict. Ideally, this would be marked as
    // required.
    analytics?: {
      ga: {
        /**
         * Google Analytics tracking ID, e.g. UA-000000-0
         * @visibility frontend
         */
        trackingId: string;

        /**
         * URL to Google Analytics analytics.js script
         * Defaults to fetching from GA source (eg. https://www.google-analytics.com/analytics.js)
         * @visibility frontend
         */
        scriptSrc?: string;

        /**
         * Controls how the identityApi is used when sending data to GA:
         *
         * - `disabled`: (Default) Explicitly prevents a user's identity from
         *   being used when capturing events in GA.
         * - `optional`: Pageviews and hits are forwarded to GA as they happen
         *   and only include user identity metadata once known. Guarantees
         *   that hits are captured for all sessions, even if no sign in
         *   occurs, but may result in dropped hits in User ID views.
         * - `required`: All pageviews and hits are deferred until an identity
         *   is known. Guarantees that all data sent to GA correlates to a user
         *   identity, but prevents GA from receiving events for sessions in
         *   which a user does not sign in. An `identityApi` instance must be
         *   passed during instantiation when set to this value.
         *
         * @visibility frontend
         */
        identity?: 'disabled' | 'optional' | 'required';

        /**
         * Controls whether to send virtual pageviews on `search` events.
         * Can be used to enable Site Search in GA.
         */
        virtualSearchPageView?: {
          /**
           * - `disabled`: (Default) no virtual pageviews are sent
           * - `only`: Sends virtual pageview _instead_ of the `search` event
           * - `both`: Sends both the `search` event _and_ the virtual pageview
           * @visibility frontend
           */
          mode?: 'disabled' | 'only' | 'both';
          /**
           * Specifies on which path the main Search page is mounted.
           * Defaults to `/search`.
           * @visibility frontend
           */
          mountPath?: string;
          /**
           * Specifies which query param is used for the term query in the virtual pageview URL.
           * Defaults to `query`.
           * @visibility frontend
           */
          searchQuery?: string;
          /**
           * Specifies which query param is used for the category query in the virtual pageview URL.
           * Skipped by default.
           * @visibility frontend
           */
          categoryQuery?: string;
        };

        /**
         * Whether or not to log analytics debug statements to the console.
         * Defaults to false.
         *
         * @visibility frontend
         */
        debug?: boolean;

        /**
         * Prevents events from actually being sent when set to true. Defaults
         * to false.
         *
         * @visibility frontend
         */
        testMode?: boolean;

        /**
         * Configuration informing how Analytics Context and Event Attributes
         * metadata will be captured in Google Analytics.
         */
        customDimensionsMetrics?: Array<{
          /**
           * Specifies whether the corresponding metadata should be collected
           * as a Google Analytics custom dimension or custom metric.
           *
           * @visibility frontend
           */
          type: 'dimension' | 'metric';

          /**
           * The index of the Google Analytics custom dimension or metric that
           * the metadata should be written to.
           *
           * @visibility frontend
           */
          index: number;

          /**
           * Specifies whether the desired value lives as an attribute on the
           * Analytics Context or the Event's Attributes.
           *
           * @visibility frontend
           */
          source: 'context' | 'attributes';

          /**
           * The property of the context or attributes that should be captured.
           * e.g. to capture the Plugin ID associated with an event, the source
           * should be set to "context" and the key should be set to pluginId.
           *
           * @visibility frontend
           */
          key: string;
        }>;
      };
    };
  };
}