packages/charts/src/common/config_objects.ts

/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the Elastic License
 * 2.0 and the Server Side Public License, v 1; you may not use this file except
 * in compliance with, at your election, the Elastic License 2.0 or the Server
 * Side Public License, v 1.
 */

interface PlainConfigItem {
  type: 'group' | 'color' | 'string' | 'boolean' | 'number';
  dflt?: any;
  min?: number;
  max?: number;
  reconfigurable?: boolean | string;
  values?: unknown;
  documentation?: string;
}

interface GroupConfigItem extends PlainConfigItem {
  type: 'group';
  values: Record<string, PlainConfigItem>;
}

// switching to `io-ts` style, generic way of combining static and runtime type info - 1st step
class Type<A> {
  dflt: A;

  reconfigurable: boolean | string;

  documentation: string;

  constructor(dflt: A, reconfigurable: boolean | string, documentation: string) {
    this.dflt = dflt;
    this.reconfigurable = reconfigurable;
    this.documentation = documentation;
  }
}

/** @internal */
export class Numeric extends Type<number> {
  min: number;

  max: number;

  type = 'number';

  constructor({
    dflt,
    min,
    max,
    reconfigurable,
    documentation,
  }: {
    dflt: number;
    min: number;
    max: number;
    reconfigurable: boolean | string;
    documentation: string;
  }) {
    super(dflt, reconfigurable, documentation);
    this.min = min;
    this.max = max;
  }
}

/** @internal */
export type ConfigItem = PlainConfigItem | Numeric;

function isGroupConfigItem(item: ConfigItem): item is GroupConfigItem {
  return item.type === 'group';
}

/** todo switch to `io-ts` style, generic way of combining static and runtime type info
 * @internal
 */
export function configMap<Conf>(mapper: (v: ConfigItem) => unknown, cfgMetadata: Record<string, ConfigItem>): Conf {
  return Object.assign(
    {},
    ...Object.entries(cfgMetadata).map(([k, v]: [string, ConfigItem]) => {
      if (isGroupConfigItem(v)) {
        return { [k]: configMap<Conf>(mapper, v.values) };
      }
      return { [k]: mapper(v) };
    }),
  );
}