/**
 * Sampling Strategies
 * Control which spans are exported for production optimization
 */
import type { SamplerConfig, SamplingRule, SpanData, Sampler } from "../../types/index.js";
/**
 * Always sample all spans
 */
export declare class AlwaysSampler implements Sampler {
    readonly name = "always";
    shouldSample(_span: SpanData): boolean;
    getDescription(): string;
}
/**
 * Never sample any spans
 */
export declare class NeverSampler implements Sampler {
    readonly name = "never";
    shouldSample(_span: SpanData): boolean;
    getDescription(): string;
}
/**
 * Sample spans based on a probability ratio
 */
export declare class RatioSampler implements Sampler {
    readonly name = "ratio";
    private readonly ratio;
    constructor(ratio: number);
    shouldSample(_span: SpanData): boolean;
    getDescription(): string;
}
/**
 * Sample based on trace ID for consistent sampling across a trace
 */
export declare class TraceIdRatioSampler implements Sampler {
    readonly name = "trace-id-ratio";
    private readonly ratio;
    private readonly upperBound;
    constructor(ratio: number);
    shouldSample(span: SpanData): boolean;
    getDescription(): string;
}
/**
 * Sample based on span attributes (e.g., errors, specific providers)
 */
export declare class AttributeBasedSampler implements Sampler {
    readonly name = "attribute-based";
    private readonly rules;
    private readonly defaultSampler;
    constructor(rules: SamplingRule[], defaultSampler?: Sampler);
    shouldSample(span: SpanData): boolean;
    private matchesRule;
    getDescription(): string;
}
/**
 * Priority-based sampler - always sample high-priority spans
 */
export declare class PrioritySampler implements Sampler {
    readonly name = "priority";
    private readonly highPriorityTypes;
    private readonly fallbackSampler;
    constructor(highPriorityTypes?: string[], fallbackSampler?: Sampler);
    shouldSample(span: SpanData): boolean;
    getDescription(): string;
}
/**
 * Error-only sampler - only sample error spans
 */
export declare class ErrorOnlySampler implements Sampler {
    readonly name = "error-only";
    shouldSample(span: SpanData): boolean;
    getDescription(): string;
}
/**
 * Composite sampler that combines multiple samplers
 */
export declare class CompositeSampler implements Sampler {
    readonly name = "composite";
    private readonly samplers;
    private readonly totalWeight;
    constructor(samplers: Array<{
        sampler: Sampler;
        weight: number;
    }>);
    shouldSample(span: SpanData): boolean;
    getDescription(): string;
}
/**
 * Custom sampler that uses a user-provided function
 */
export declare class CustomSampler implements Sampler {
    readonly name = "custom";
    private readonly sampleFn;
    private readonly description;
    constructor(sampleFn: (span: SpanData) => boolean, description?: string);
    shouldSample(span: SpanData): boolean;
    getDescription(): string;
}
/**
 * Factory for creating samplers from configuration
 */
export declare class SamplerFactory {
    static create(config: SamplerConfig): Sampler;
}