import { type ConfigSource } from '../spi/config-source.js';
import { type ConfigAccessor } from '../spi/config-accessor.js';
import { type Refreshable } from '../spi/refreshable.js';
/**
 * Represents a single application wide multi-layer configuration.
 */
export interface Config extends ConfigAccessor, Refreshable {
    /**
     * All the configuration sources which were used to build this configuration.
     */
    readonly sources: ConfigSource[];
    /**
     * Adds a configuration source to the configuration.
     *
     * This method is not guaranteed to be thread-safe, so it should not be called concurrently with other methods
     * that modify the configuration. Methods which read the configuration may be called concurrently, but may not
     * reflect changes made by this method.
     *
     * This method is typically used to add configuration sources that have been created or loaded dynamically,
     * such as configuration files, environment variables, or other sources of configuration data.
     *
     * The same {@link ConfigSource} instance can only be added once. If the same source is added again, a
     * DuplicateConfigSourceError will be thrown. This is to ensure that each configuration source is unique within
     * the configuration.
     *
     * A {@link ConfigSource} with the same name and ordinal as an existing source will be considered a duplicate,
     * even if it is a different instance.
     *
     * @param source - The configuration source to be added.
     * @throws {DuplicateConfigSourceError} if the configuration source has already been added.
     */
    addSource(source: ConfigSource): void;
}