/**
 * @license
 * Copyright 2025 OSAgent OC
 * SPDX-License-Identifier: Apache-2.0
 */
import type { EmbeddingProvider, EmbeddingResult, EmbeddingServiceConfig } from './types.js';
/**
 * Embedding Service
 *
 * Provides a unified interface for text embeddings with:
 * - Primary/fallback provider support
 * - Automatic fallback on failure
 * - Optional caching
 * - Batch operations
 *
 * Default configuration:
 * - Primary: Ollama (local, free)
 * - Fallback: OpenRouter (cloud, paid)
 */
export declare class EmbeddingService {
    private primary;
    private fallback;
    private cache;
    private readonly maxBatchSize;
    constructor(config?: EmbeddingServiceConfig);
    /**
     * Create service with default providers
     */
    static createDefault(openRouterApiKey?: string): EmbeddingService;
    /**
     * Initialize and validate providers
     */
    initialize(): Promise<{
        primary: boolean;
        fallback: boolean;
    }>;
    /**
     * Get active provider (for dimension info, etc.)
     */
    getActiveProvider(): Promise<EmbeddingProvider | null>;
    /**
     * Get embedding dimensions from active provider
     */
    getDimensions(): Promise<number>;
    /**
     * Generate embedding for a single text
     */
    embed(text: string): Promise<EmbeddingResult>;
    /**
     * Generate embeddings for multiple texts
     */
    embedBatch(texts: string[]): Promise<EmbeddingResult[]>;
    /**
     * Process batch with size limit
     */
    private batchWithLimit;
    /**
     * Calculate cosine similarity between two embeddings
     */
    static cosineSimilarity(a: number[], b: number[]): number;
    /**
     * Clear the embedding cache
     */
    clearCache(): void;
    /**
     * Get cache statistics
     */
    getCacheStats(): {
        size: number;
        enabled: boolean;
    };
    /**
     * Check if service has any available provider
     */
    isAvailable(): Promise<boolean>;
}
export declare function getDefaultEmbeddingService(openRouterApiKey?: string): EmbeddingService;