/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
import {Joi} from '@docusaurus/utils-validation';
import type {
  OptionValidationContext,
  ThemeConfig,
  ThemeConfigValidationContext,
} from '@docusaurus/types';

export type PluginOptions = {
  trackingID: [string, ...string[]];
  // TODO deprecate anonymizeIP after June 2023
  // "In Google Analytics 4, IP masking is not necessary
  // since IP addresses are not logged or stored."
  // https://support.google.com/analytics/answer/2763052?hl=en
  anonymizeIP: boolean;
};

export type Options = {
  trackingID: string | [string, ...string[]];
  anonymizeIP?: boolean;
};

export const DEFAULT_OPTIONS: Partial<PluginOptions> = {
  anonymizeIP: false,
};

const pluginOptionsSchema = Joi.object<PluginOptions>({
  // We normalize trackingID as a string[]
  trackingID: Joi.alternatives()
    .try(
      Joi.alternatives().conditional(Joi.string().required(), {
        then: Joi.custom((val: boolean) => [val]),
      }),
      Joi.array().items(Joi.string().required()),
    )
    .required(),
  anonymizeIP: Joi.boolean().default(DEFAULT_OPTIONS.anonymizeIP),
});

export function validateOptions({
  validate,
  options,
}: OptionValidationContext<Options, PluginOptions>): PluginOptions {
  return validate(pluginOptionsSchema, options);
}

export function validateThemeConfig({
  themeConfig,
}: ThemeConfigValidationContext<ThemeConfig>): ThemeConfig {
  if ('gtag' in themeConfig) {
    throw new Error(
      'The "gtag" field in themeConfig should now be specified as option for plugin-google-gtag. More information at https://github.com/facebook/docusaurus/pull/5832.',
    );
  }
  return themeConfig;
}