import type { DatadogMetricsConfig } from '../../utils/index.js';
/**
 * Datadog metrics client for sending custom metrics
 * Provides a wrapper around the datadog-metrics library with initialization and error handling
 *
 * @example
 * ```typescript
 * // Initialize the metrics client
 * const config = { apiKey: 'your-key', prefix: 'app.' };
 * DatadogMetrics.initialize(config);
 *
 * // Send metrics
 * DatadogMetrics.increment('requests.count', 1, ['service:api']);
 * DatadogMetrics.gauge('memory.usage', 75.5, ['unit:percentage']);
 * ```
 */
export declare class DatadogMetrics {
    private static metricsClient;
    private static config;
    /**
     * Initialize the Datadog metrics client with configuration
     *
     * @param config - The Datadog metrics configuration object
     * @returns The initialized metrics client instance
     * @example
     * ```typescript
     * const config = {
     *   apiKey: 'your-datadog-api-key',
     *   prefix: 'myapp.',
     *   host: 'localhost'
     * };
     * const client = DatadogMetrics.initialize(config);
     * ```
     */
    static initialize(config: DatadogMetricsConfig): any;
    /**
     * Get the configured metrics client instance
     *
     * @returns The metrics client instance
     * @throws Error if metrics client is not initialized
     * @example
     * ```typescript
     * try {
     *   const client = DatadogMetrics.getInstance();
     *   client.increment('custom.metric');
     * } catch (error) {
     *   console.error('Metrics client not initialized');
     * }
     * ```
     */
    static getInstance(): any;
    /**
     * Check if metrics client is initialized
     *
     * @returns True if the metrics client is initialized, false otherwise
     * @example
     * ```typescript
     * if (DatadogMetrics.isInitialized()) {
     *   DatadogMetrics.increment('app.ready');
     * }
     * ```
     */
    static isInitialized(): boolean;
    /**
     * Get current configuration
     *
     * @returns The current Datadog metrics configuration or null if not set
     * @example
     * ```typescript
     * const config = DatadogMetrics.getConfig();
     * if (config) {
     *   console.log(`Using prefix: ${config.prefix}`);
     * }
     * ```
     */
    static getConfig(): DatadogMetricsConfig | null;
    /**
     * Send a counter metric
     *
     * @param metric - The metric name to increment
     * @param value - The value to increment by (default: 1)
     * @param tags - Array of tags to attach to the metric
     * @example
     * ```typescript
     * DatadogMetrics.increment('api.requests'); // Increment by 1
     * DatadogMetrics.increment('user.actions', 5, ['action:login']);
     * ```
     */
    static increment(metric: string, value?: number, tags?: string[]): void;
    /**
     * Send a decrement metric
     *
     * @param metric - The metric name to decrement
     * @param value - The value to decrement by (default: 1)
     * @param tags - Array of tags to attach to the metric
     * @example
     * ```typescript
     * DatadogMetrics.decrement('queue.size'); // Decrement by 1
     * DatadogMetrics.decrement('active.connections', 3, ['service:db']);
     * ```
     */
    static decrement(metric: string, value?: number, tags?: string[]): void;
    /**
     * Send a gauge metric
     *
     * @param metric - The metric name to set a gauge value for
     * @param value - The gauge value to set
     * @param tags - Array of tags to attach to the metric
     * @example
     * ```typescript
     * DatadogMetrics.gauge('memory.usage', 75.5, ['unit:percentage']);
     * DatadogMetrics.gauge('queue.depth', 42, ['queue:processing']);
     * ```
     */
    static gauge(metric: string, value: number, tags?: string[]): void;
    /**
     * Send a histogram metric
     *
     * @param metric - The metric name to send histogram data for
     * @param value - The histogram value to record
     * @param tags - Array of tags to attach to the metric
     * @example
     * ```typescript
     * DatadogMetrics.histogram('response.time', 250, ['endpoint:users']);
     * DatadogMetrics.histogram('file.size', 1024, ['type:image']);
     * ```
     */
    static histogram(metric: string, value: number, tags?: string[]): void;
    /**
     * Send a timing metric (histogram with time unit)
     *
     * @param metric - The metric name to send timing data for
     * @param value - The timing value in milliseconds
     * @param tags - Array of tags to attach to the metric
     * @example
     * ```typescript
     * const start = Date.now();
     * // ... perform operation ...
     * DatadogMetrics.timing('operation.duration', Date.now() - start, ['operation:create']);
     * ```
     */
    static timing(metric: string, value: number, tags?: string[]): void;
    /**
     * Send a distribution metric
     *
     * @param metric - The metric name to send distribution data for
     * @param value - The distribution value to record
     * @param tags - Array of tags to attach to the metric
     * @example
     * ```typescript
     * DatadogMetrics.distribution('score.review', 8.5, ['reviewer:ai']);
     * DatadogMetrics.distribution('latency.network', 125, ['region:us-east']);
     * ```
     */
    static distribution(metric: string, value: number, tags?: string[]): void;
    /**
     * Send a set metric - not directly supported, use gauge instead
     *
     * @param metric - The metric name to set a value for
     * @param value - The value to set (string or number)
     * @param tags - Array of tags to attach to the metric
     * @example
     * ```typescript
     * DatadogMetrics.set('users.unique', 'user123', ['action:login']);
     * DatadogMetrics.set('ips.unique', '192.168.1.1', ['endpoint:api']);
     * ```
     */
    static set(metric: string, value: string | number, tags?: string[]): void;
    /**
     * Flush buffered metrics immediately
     *
     * @example
     * ```typescript
     * // Send all pending metrics immediately
     * DatadogMetrics.flush();
     * ```
     */
    static flush(): void;
    /**
     * Close the metrics client and clean up resources
     *
     * @example
     * ```typescript
     * // Clean shutdown of metrics client
     * DatadogMetrics.close();
     * ```
     */
    static close(): void;
}