/**
 * Provider Health Checking System
 * Prevents 500 errors by validating provider availability and configuration
 */
import { AIProviderName } from "../constants/enums.js";
import type { ProviderHealthCheckOptions, ProviderHealthStatusOptions } from "../types/index.js";
export declare class ProviderHealthChecker {
    private static healthCache;
    private static readonly DEFAULT_TIMEOUT;
    private static readonly DEFAULT_CACHE_AGE;
    private static readonly CONSECUTIVE_FAILURE_THRESHOLD;
    private static consecutiveFailures;
    /**
     * Validate and return a safe failure threshold value
     */
    private static getValidatedFailureThreshold;
    /**
     * Comprehensive health check for a provider
     */
    static checkProviderHealth(providerName: AIProviderName, options?: ProviderHealthCheckOptions): Promise<ProviderHealthStatusOptions>;
    /**
     * Check environment configuration for a provider
     */
    private static checkEnvironmentConfiguration;
    /**
     * Check API key validity (format validation)
     */
    private static checkApiKeyValidity;
    /**
     * Check connectivity to provider endpoints
     */
    private static checkConnectivity;
    private static getConnectivityHeaders;
    /**
     * Check model availability (if possible without making API calls)
     */
    private static checkModelAvailability;
    /**
     * Get required environment variables for a provider
     */
    private static getRequiredEnvironmentVariables;
    /**
     * Get API key environment variable for a provider
     */
    private static getApiKeyEnvironmentVariable;
    /**
     * Validate API key format for a provider
     */
    private static validateApiKeyFormat;
    /**
     * Get health check endpoint for connectivity testing
     */
    private static getProviderHealthEndpoint;
    /**
     * Provider-specific configuration checks
     */
    private static checkProviderSpecificConfig;
    /**
     * Check Vertex AI configuration
     */
    private static checkVertexAIConfig;
    /**
     * Get Vertex AI project ID from environment variables
     */
    private static getVertexProjectId;
    /**
     * Check Vertex AI authentication
     */
    private static checkVertexAuthentication;
    /**
     * Check Google Application Credentials file
     */
    private static checkGoogleApplicationCredentials;
    /**
     * Check individual Google credentials
     */
    private static checkIndividualGoogleCredentials;
    /**
     * Check AWS Bedrock configuration
     */
    private static checkBedrockConfig;
    /**
     * Check AWS region configuration
     */
    private static checkAWSRegion;
    /**
     * Check AWS credentials
     */
    private static checkAWSCredentials;
    /**
     * Check Bedrock models
     */
    private static checkBedrockModels;
    /**
     * Check Bedrock endpoint
     */
    private static checkBedrockEndpoint;
    /**
     * Check Azure OpenAI configuration
     */
    private static checkAzureConfig;
    private static getLiteLLMBaseUrl;
    private static getLiteLLMModelsUrl;
    private static getConfiguredLiteLLMModel;
    private static getOllamaBaseUrl;
    private static getOllamaTagsUrl;
    private static getConfiguredOllamaModel;
    private static fetchJsonWithTimeout;
    private static normalizeModelList;
    private static hasRequestedModel;
    private static getOllamaAvailableModels;
    private static getLiteLLMAvailableModels;
    private static checkOllamaAvailability;
    private static checkLiteLLMAvailability;
    private static checkLiteLLMConfig;
    /**
     * Check Ollama configuration
     */
    private static checkOllamaConfig;
    /**
     * Get common models for a provider
     */
    private static getCommonModelsForProvider;
    /**
     * Get cached health status if still valid
     */
    private static getCachedHealth;
    /**
     * Check if Vertex AI supports Anthropic models (dual provider architecture)
     */
    static checkVertexAnthropicSupport(): Promise<{
        isSupported: boolean;
        hasCreateVertexAnthropic: boolean;
        hasCorrectTypes: boolean;
        hasValidProject: boolean;
        hasRegionalSupport: boolean;
        hasNetworkAccess: boolean;
        hasAnthropicModels: boolean;
        authentication: {
            isValid: boolean;
            method: string;
            issues: string[];
        };
        projectConfiguration: {
            isValid: boolean;
            projectId: string | undefined;
            region: string | undefined;
            issues: string[];
        };
        modelSupport: {
            availableModels: string[];
            recommendedModels: string[];
            deprecatedModels: string[];
        };
        recommendations: string[];
        troubleshooting: string[];
    }>;
    /**
     * Validate Vertex AI authentication configuration
     */
    private static validateVertexAuthentication;
    /**
     * Validate Vertex AI project configuration
     */
    private static validateVertexProjectConfiguration;
    /**
     * Check if the specified region supports Anthropic models
     */
    private static checkVertexRegionalSupport;
    /**
     * Check network connectivity to Vertex AI endpoints
     */
    private static checkVertexNetworkConnectivity;
    /**
     * Check if Anthropic model integration is enabled in the project
     */
    private static checkAnthropicModelIntegration;
    /**
     * Initialize health checks in the background (NON-BLOCKING)
     * Starts background health monitoring without blocking initialization
     */
    static initializeBackgroundHealthChecks(): void;
    /**
     * Clear health cache for a provider or all providers
     */
    static clearHealthCache(providerName?: AIProviderName): void;
    static checkFallbackProviderAvailability(providerName: string, model: string): Promise<{
        available: boolean;
        reason?: string;
    }>;
    /**
     * Get the best healthy provider from a list of options (NON-BLOCKING)
     * Prioritizes healthy providers over configured but unhealthy ones
     * Uses fast, cached health checks to avoid blocking initialization
     */
    static getBestHealthyProvider(preferredProviders?: string[]): Promise<string | null>;
    /**
     * Get health status for all registered providers
     */
    static checkAllProvidersHealth(options?: ProviderHealthCheckOptions): Promise<ProviderHealthStatusOptions[]>;
    /**
     * Get a summary of provider health
     */
    static getHealthSummary(healthStatuses: ProviderHealthStatusOptions[]): {
        total: number;
        healthy: number;
        configured: number;
        hasIssues: number;
        healthyProviders: string[];
        unhealthyProviders: string[];
    };
}