/**
 * YAML/JSON proxy configuration loader with environment variable resolution.
 *
 * Supports:
 * - Loading config from YAML or JSON files
 * - Environment variable interpolation: ${VAR_NAME} and ${VAR_NAME:-default}
 * - Multi-account proxy configurations
 * - Defaults for optional fields
 *
 * YAML parsing uses `js-yaml` when available (dynamic import), otherwise
 * falls back to JSON.parse.
 */
import type { LoadProxyConfigOptions, ProxyConfigFile, ProxyRoutingConfig } from "../types/index.js";
/** Default on-disk path used when `proxy start` is not given `--config`. */
export declare function defaultProxyConfigPath(): string;
/** Resolve `--config` the same way `proxy start` / `proxy install` do. */
export declare function resolveProxyConfigPath(explicit?: string): string;
/**
 * Replace all `${VAR}` / `${VAR:-default}` references in a string.
 *
 * Resolution order:
 * 1. Look up `VAR` in the provided env map (or process.env)
 * 2. If not found, use the `:-default` value when present
 * 3. If no default, leave the original `${VAR}` token so callers can detect
 *    unresolved variables.
 */
export declare function resolveEnvVars(value: string, env?: Record<string, string | undefined>): string;
/**
 * Validate the shape of a parsed proxy config.
 * Returns an array of human-readable error strings (empty = valid).
 */
export declare function validateProxyConfig(config: unknown): string[];
/**
 * Parse the optional `routing` section from a raw proxy config object.
 *
 * Extracts:
 * - `strategy` ("round-robin" | "fill-first")
 * - `model-mappings` / `modelMappings` — array of {from, to, provider}
 * - `fallback-chain` / `fallbackChain` — array of {provider, model, reasoningEffort?}
 * - `auto-fallback` / `autoFallback` — opt in to an unspecified provider
 * - `max-inflight-per-account` / `maxInflightPerAccount` — concurrency cap
 * - `passthroughModels` / `passthrough-models` — array of model IDs
 * - `quota-routing` / `quotaRouting` — quota-aware fill-first ordering
 * - `session-soft-limit` / `sessionSoftLimit` — proactive handoff threshold
 * - `session-reset-tolerance-ms` / `sessionResetToleranceMs` — reset bucket
 * - `account-allowlist` / `accountAllowlist` — allowed Anthropic account IDs
 * - `account-ranking` / `accountRanking` — expiry-first | headroom-first
 * - `prefer-primary` / `preferPrimary` — bias ranking toward primaryAccount
 * - `session-affinity` / `sessionAffinity` — sticky-session binding
 * - `session-affinity-idle-ttl-ms` / `sessionAffinityIdleTtlMs` — idle unbind
 * - `spill-inflight` / `spillInflight` — overflow threshold for sticky sessions
 *
 * Accepts both camelCase and kebab-case keys for YAML-friendliness.
 */
export declare function parseRoutingConfig(raw: Record<string, unknown> | undefined): Partial<ProxyRoutingConfig> | undefined;
/**
 * Load and parse a proxy configuration file (YAML or JSON).
 *
 * @param filePath - Absolute or relative path to the config file.
 * @param options  - Optional settings for env resolution.
 * @returns Parsed and validated ProxyConfigFile.
 * @throws When the file cannot be read, parsed, or fails validation.
 */
export declare function loadProxyConfig(filePath: string, options?: LoadProxyConfigOptions): Promise<ProxyConfigFile>;
/**
 * Load proxy config from a raw string (YAML or JSON) instead of a file path.
 * Useful for testing or when config is stored in environment variables.
 */
export declare function parseProxyConfigString(content: string, options?: LoadProxyConfigOptions): Promise<ProxyConfigFile>;