import type { Config, Nullable } from "../types/index.js";
/**
 * CLI override map. Keys are dot-separated CONFIG_METADATA paths (e.g., "server.port", "paths.chromeDataDir"). Values are the parsed CLI flag values. Applied as the
 * highest-priority merge pass in mergeConfiguration().
 */
export type CliOverrides = Record<string, unknown>;
export declare let CONFIG: Config;
/**
 * Indicates whether a user config file parse error occurred during initialization. The web UI displays a warning when this is true.
 */
export declare let configParseError: boolean;
/**
 * The parse error message if configParseError is true.
 */
export declare let configParseErrorMessage: string | undefined;
/**
 * Initializes the configuration by loading the user config file, merging with defaults, applying environment variable overrides, and applying CLI overrides. This
 * must be called at startup before any code accesses CONFIG. After initialization, the CONFIG object contains the final merged values.
 * @param cliOverrides - Optional CLI flag overrides, applied at the highest priority level.
 */
export declare function initializeConfiguration(cliOverrides?: CliOverrides): Promise<void>;
/**
 * Returns a deep copy of the default configuration. Used by the web UI to display default values and handle reset operations.
 * @returns A copy of the default configuration.
 */
export declare function getDefaults(): Config;
/**
 * Validates that a configuration value is a positive integer within an optional range. This helper performs the common validation pattern of checking for valid
 * integers and enforcing minimum/maximum bounds. It returns an error message if validation fails, allowing the caller to collect all errors before reporting them.
 * @param name - The configuration name for error messages, typically the environment variable name.
 * @param value - The value to validate, typically parsed from an environment variable.
 * @param min - Optional minimum allowed value (inclusive).
 * @param max - Optional maximum allowed value (inclusive).
 * @returns Error message if invalid, null if valid.
 */
export declare function validatePositiveInt(name: string, value: number, min?: number, max?: number): Nullable<string>;
/**
 * Validates that a configuration value is a positive number (including floats) within an optional range.
 * @param name - The configuration name for error messages.
 * @param value - The value to validate.
 * @param min - Optional minimum allowed value (inclusive).
 * @param max - Optional maximum allowed value (inclusive).
 * @returns Error message if invalid, null if valid.
 */
export declare function validatePositiveNumber(name: string, value: number, min?: number, max?: number): Nullable<string>;
/**
 * Validates all configuration values and throws an error if any are invalid. This function runs at startup after configuration initialization. We collect all
 * validation errors before throwing to provide complete feedback rather than failing on the first error and requiring multiple restart cycles to find all problems.
 * @throws If any configuration value is invalid. The error message lists all invalid values.
 */
export declare function validateConfiguration(): void;
/**
 * Displays the active configuration at startup. This helps operators verify their settings and diagnose connection issues. We log only the most commonly adjusted
 * values to keep output concise while providing useful debugging information.
 *
 * This function also checks for preset degradation and logs a warning if the configured preset exceeds display capabilities. The warning helps users understand why
 * their stream resolution may be lower than configured.
 */
export declare function displayConfiguration(): void;