/**
 * API Variable Service
 * Handles fetching template variable schemas from REST endpoints at runtime.
 * Enables dynamic variable suggestions from backend APIs for template editors.
 *
 * @module services/apiVariableService
 */
import type { VariableSchema, ApiVariablesConfig, AuthProvider } from '../types/index.js';
/**
 * Context for variable API requests
 */
interface VariableContext {
    /** Workflow ID */
    workflowId?: string;
    /** Node instance ID */
    nodeId: string;
}
/**
 * Result of a variable schema fetch operation
 */
export interface ApiVariableResult {
    /** Whether the fetch was successful */
    success: boolean;
    /** The fetched variable schema (if successful) */
    schema?: VariableSchema;
    /** Error message (if failed) */
    error?: string;
    /** Whether the schema was loaded from cache */
    fromCache?: boolean;
}
/** Default cache TTL for variable data */
export declare const DEFAULT_VARIABLE_CACHE_TTL: number;
/**
 * Replaces {workflowId} and {nodeId} placeholders in URL template.
 *
 * @param template - The URL template string
 * @param context - The variable context with workflowId and nodeId
 * @returns The resolved URL with placeholders replaced
 *
 * @example
 * ```typescript
 * const url = "/api/variables/{workflowId}/{nodeId}";
 * const context = { workflowId: "wf-123", nodeId: "node-456" };
 * resolveEndpointUrl(url, context);
 * // Returns "/api/variables/wf-123/node-456"
 * ```
 */
export declare function resolveEndpointUrl(template: string, context: VariableContext): string;
/**
 * Fetches variable schema from a backend API endpoint.
 *
 * @param workflowId - The workflow ID (optional)
 * @param nodeId - The node instance ID
 * @param config - The API variables configuration
 * @param authProvider - Optional auth provider for auth headers
 * @returns A promise that resolves to the variable schema result
 *
 * @example
 * ```typescript
 * const config: ApiVariablesConfig = {
 *   endpoint: {
 *     url: "/api/variables/{workflowId}/{nodeId}",
 *     method: "GET"
 *   },
 *   cacheTtl: 300000
 * };
 *
 * const result = await fetchVariableSchema("wf-123", "node-456", config);
 * if (result.success && result.schema) {
 *   // Use the fetched variable schema
 * }
 * ```
 */
export declare function fetchVariableSchema(workflowId: string | undefined, nodeId: string, config: ApiVariablesConfig, authProvider?: AuthProvider): Promise<ApiVariableResult>;
/**
 * Clears the variable schema cache.
 * Can optionally clear only entries matching a specific pattern.
 *
 * @param pattern - Optional pattern to match cache keys (e.g., workflow ID or node ID)
 *
 * @example
 * ```typescript
 * // Clear all cache
 * clearVariableCache();
 *
 * // Clear cache for a specific workflow
 * clearVariableCache("wf-123");
 *
 * // Clear cache for a specific node
 * clearVariableCache("node-456");
 * ```
 */
export declare function clearVariableCache(pattern?: string): void;
/**
 * Invalidates a specific variable cache entry.
 *
 * @param workflowId - The workflow ID (optional)
 * @param nodeId - The node instance ID
 */
export declare function invalidateVariableCache(workflowId: string | undefined, nodeId: string): void;
/**
 * Gets the current cache size (number of entries).
 *
 * @returns The number of cached variable schemas
 */
export declare function getVariableCacheSize(): number;
/**
 * Gets all cache keys currently stored.
 * Useful for debugging and monitoring.
 *
 * @returns Array of cache keys
 */
export declare function getVariableCacheKeys(): string[];
export {};