config.ts

import type { NearestNode, NodeConfiguration, TsNode } from "@/node";

import { initializeNodes } from "@/node";

import type { MakeRequestInit } from "@/http/fetch/request";

interface BaseConfiguration {
  apiKey: string;
  randomizeNodes?: boolean;
  connectionTimeoutSeconds?: number;
  timeoutSeconds?: number;
  healthcheckIntervalSeconds?: number;
  numRetries?: number;
  retryIntervalSeconds?: number;
  sendApiKeyAsQueryParam?: boolean;
  additionalHeaders?: Record<string, string>;
  fetch?: {
    fn?: typeof fetch;
    init?: MakeRequestInit;
  }
}

type MakeKeysRequired<T, K extends keyof T> = T & {
  [P in K]-?: T[P];
};

interface CreateConfiguration extends BaseConfiguration {
  nodes: NodeConfiguration[];
  nearestNode?: NodeConfiguration;
}

interface Configuration
  extends MakeKeysRequired<
    BaseConfiguration,
    "healthcheckIntervalSeconds" | "numRetries" | "retryIntervalSeconds"
  > {
  nodes: TsNode[];
  nearestNode?: NearestNode;
}

function configure(config: CreateConfiguration): Configuration {
  const { nodes, nearestNode } = initializeNodes({
    nodes: config.nodes,
    nearestNode: config.nearestNode,
  });

  const numRetries =
    config.numRetries && config.numRetries >= 0 ?
      config.numRetries
    : nodes.length + (nearestNode ? 0 : 1);

  const healthcheckIntervalSeconds = config.healthcheckIntervalSeconds ?? 60;
  const retryIntervalSeconds = config.retryIntervalSeconds ?? 1;

  return {
    ...config,
    nodes,
    nearestNode,
    numRetries,
    healthcheckIntervalSeconds,
    retryIntervalSeconds,
  };
}

let defaultConfiguration: Configuration | null = null;

/**
 * Sets the default configuration that will be used by all HTTP methods
 * when no config is explicitly provided.
 */
function setDefaultConfiguration(config: CreateConfiguration): void {
  defaultConfiguration = configure(config);
}

/**
 * Gets the current default configuration.
 * Throws an error if no default configuration has been set.
 */
function getDefaultConfiguration(): Configuration {
  if (!defaultConfiguration) {
    throw new Error(
      "No default configuration has been set. Please call `setDefaultConfiguration()` first or pass a config parameter to the method.",
    );
  }
  return defaultConfiguration;
}

/**
 * Gets the configuration to use - either the provided config or the default one.
 */
function getConfiguration(config?: Configuration): Configuration {
  return config ?? getDefaultConfiguration();
}

/**
 * Clears the default configuration.
 */
function clearDefaultConfiguration(): void {
  defaultConfiguration = null;
}

export type { Configuration };

export {
  configure,
  setDefaultConfiguration,
  getDefaultConfiguration,
  getConfiguration,
  clearDefaultConfiguration,
};