@clduab11/gemini-flow/src/core/auth/mcp-auth-provider.ts

Revolutionary AI agent swarm coordination platform with Google Services integration, multimedia processing, and production-ready monitoring. Features 8 Google AI services, quantum computing capabilities, and enterprise-grade security.

/**
 * MCP Authentication Provider
 *
 * Model Context Protocol authentication integration that provides authentication
 * capabilities as MCP tools and handles authentication requests from MCP clients
 */

import { EventEmitter } from "events";
import { Logger } from "../../utils/logger.js";
import { UnifiedAuthManager } from "./unified-auth-manager.js";
import {
  MCPAuthCapability,
  MCPAuthProvider,
  AuthenticationResult,
  RefreshTokenResult,
  ValidationResult,
  AuthCredentials,
  AuthProviderType,
  AuthError,
} from "../../types/auth.js";

/**
 * MCP Auth Provider Configuration
 */
export interface MCPAuthProviderConfig {
  version: string;
  enabledCapabilities: string[];
  maxConcurrentRequests: number;
  requestTimeoutMs: number;
  enableMetrics: boolean;
  enableCaching: boolean;
}

/**
 * MCP request context
 */
interface MCPRequestContext {
  requestId: string;
  method: string;
  timestamp: number;
  clientId?: string;
  timeout?: ReturnType<typeof setTimeout>;
}

/**
 * MCP authentication metrics
 */
export interface MCPAuthMetrics {
  totalRequests: number;
  successfulRequests: number;
  failedRequests: number;
  averageResponseTime: number;
  activeRequests: number;
  capabilityUsage: Record<string, number>;
  errorsByType: Record<string, number>;
}

/**
 * MCP Authentication Provider Implementation
 */
export class MCPAuthenticationProvider
  extends EventEmitter
  implements MCPAuthProvider
{
  public readonly name = "mcp-auth";
  public readonly version: string;

  private authManager: UnifiedAuthManager;
  private config: MCPAuthProviderConfig;
  private logger: Logger;

  // Request tracking
  private activeRequests = new Map<string, MCPRequestContext>();
  private requestCounter = 0;

  // Metrics
  private metrics: MCPAuthMetrics = {
    totalRequests: 0,
    successfulRequests: 0,
    failedRequests: 0,
    averageResponseTime: 0,
    activeRequests: 0,
    capabilityUsage: {},
    errorsByType: {},
  };

  // Capabilities registry
  public readonly capabilities: MCPAuthCapability[] = [
    {
      method: "auth/authenticate",
      description: "Authenticate using specified provider and credentials",
      parameters: {
        provider: {
          type: "string",
          required: true,
          description: "Authentication provider type",
        },
        credentials: {
          type: "object",
          required: false,
          description: "Provider-specific credentials",
        },
        options: {
          type: "object",
          required: false,
          description: "Additional authentication options",
        },
      },
      required: true,
      version: "1.0.0",
    },
    {
      method: "auth/refresh",
      description: "Refresh authentication tokens",
      parameters: {
        sessionId: {
          type: "string",
          required: true,
          description: "Authentication session ID",
        },
        forceRefresh: {
          type: "boolean",
          required: false,
          description: "Force refresh even if not expired",
        },
      },
      required: true,
      version: "1.0.0",
    },
    {
      method: "auth/validate",
      description: "Validate authentication credentials",
      parameters: {
        sessionId: {
          type: "string",
          required: true,
          description: "Authentication session ID",
        },
        checkExpiry: {
          type: "boolean",
          required: false,
          description: "Check token expiration",
        },
      },
      required: true,
      version: "1.0.0",
    },
    {
      method: "auth/revoke",
      description: "Revoke authentication credentials",
      parameters: {
        sessionId: {
          type: "string",
          required: true,
          description: "Authentication session ID",
        },
      },
      required: true,
      version: "1.0.0",
    },
    {
      method: "auth/status",
      description: "Get authentication status and session information",
      parameters: {
        sessionId: {
          type: "string",
          required: false,
          description: "Specific session ID (optional)",
        },
      },
      required: false,
      version: "1.0.0",
    },
    {
      method: "auth/capabilities",
      description: "List available authentication capabilities",
      parameters: {},
      required: false,
      version: "1.0.0",
    },
    {
      method: "auth/providers",
      description: "List available authentication providers",
      parameters: {},
      required: false,
      version: "1.0.0",
    },
    {
      method: "auth/metrics",
      description: "Get authentication metrics and statistics",
      parameters: {
        includeDetailed: {
          type: "boolean",
          required: false,
          description: "Include detailed metrics",
        },
      },
      required: false,
      version: "1.0.0",
    },
  ];

  constructor(
    authManager: UnifiedAuthManager,
    config: Partial<MCPAuthProviderConfig> = {},
  ) {
    super();

    this.authManager = authManager;
    this.config = {
      version: config.version || "1.0.0",
      enabledCapabilities:
        config.enabledCapabilities || this.capabilities.map((c) => c.method),
      maxConcurrentRequests: config.maxConcurrentRequests || 50,
      requestTimeoutMs: config.requestTimeoutMs || 30000,
      enableMetrics: config.enableMetrics ?? true,
      enableCaching: config.enableCaching ?? true,
      ...config,
    };

    this.version = this.config.version;
    this.logger = new Logger("MCPAuthProvider");

    // Filter capabilities based on enabled list
    this.capabilities = this.capabilities.filter((cap) =>
      this.config.enabledCapabilities.includes(cap.method),
    );

    this.logger.info("MCP Auth Provider initialized", {
      version: this.version,
      capabilities: this.capabilities.length,
      maxConcurrentRequests: this.config.maxConcurrentRequests,
    });
  }

  /**
   * Handle MCP authentication request
   */
  async authenticate(params: any): Promise<AuthenticationResult> {
    const requestId = this.generateRequestId();
    const startTime = Date.now();

    try {
      this.logger.info("MCP authenticate request", {
        requestId,
        params: Object.keys(params),
      });

      // Track request
      const context = this.createRequestContext(requestId, "auth/authenticate");
      this.trackRequest(context);

      // Validate parameters
      this.validateAuthenticateParams(params);

      // Check concurrent request limit
      if (this.activeRequests.size >= this.config.maxConcurrentRequests) {
        throw this.createMCPError(
          "REQUEST_LIMIT_EXCEEDED",
          "Maximum concurrent requests exceeded",
        );
      }

      const { provider, credentials, options = {} } = params;

      // Authenticate using unified auth manager
      const result = await this.authManager.authenticate(
        provider as AuthProviderType,
        {
          ...options,
          mcpRequestId: requestId,
          source: "mcp",
        },
      );

      // Update metrics
      this.updateMetrics("auth/authenticate", true, Date.now() - startTime);

      this.logger.info("MCP authenticate successful", {
        requestId,
        provider,
        success: result.success,
        duration: Date.now() - startTime,
      });

      return result;
    } catch (error) {
      this.updateMetrics("auth/authenticate", false, Date.now() - startTime);

      const authError =
        error instanceof Error
          ? error
          : new Error("Unknown authentication error");
      this.logger.error("MCP authenticate failed", {
        requestId,
        error: authError,
      });

      return {
        success: false,
        error: this.createAuthError(
          "AUTHENTICATION_FAILED",
          authError.message,
          authError,
        ),
      };
    } finally {
      this.untrackRequest(requestId);
    }
  }

  /**
   * Handle MCP token refresh request
   */
  async refresh(params: any): Promise<RefreshTokenResult> {
    const requestId = this.generateRequestId();
    const startTime = Date.now();

    try {
      this.logger.info("MCP refresh request", {
        requestId,
        sessionId: params.sessionId,
      });

      const context = this.createRequestContext(requestId, "auth/refresh");
      this.trackRequest(context);

      this.validateRefreshParams(params);

      const { sessionId, forceRefresh = false } = params;

      // Check if refresh is needed (unless forced)
      if (!forceRefresh) {
        const validation =
          await this.authManager.validateCredentials(sessionId);
        if (validation.valid && !validation.expired) {
          // No refresh needed
          const session = this.authManager.getSession(sessionId);
          return {
            success: true,
            credentials: session?.context.credentials,
          };
        }
      }

      const result = await this.authManager.refreshCredentials(sessionId);

      this.updateMetrics(
        "auth/refresh",
        result.success,
        Date.now() - startTime,
      );

      this.logger.info("MCP refresh completed", {
        requestId,
        sessionId,
        success: result.success,
        duration: Date.now() - startTime,
      });

      return result;
    } catch (error) {
      this.updateMetrics("auth/refresh", false, Date.now() - startTime);

      const authError =
        error instanceof Error ? error : new Error("Unknown refresh error");
      this.logger.error("MCP refresh failed", { requestId, error: authError });

      return {
        success: false,
        error: this.createAuthError(
          "REFRESH_FAILED",
          authError.message,
          authError,
        ),
      };
    } finally {
      this.untrackRequest(requestId);
    }
  }

  /**
   * Handle MCP credential validation request
   */
  async validate(params: any): Promise<ValidationResult> {
    const requestId = this.generateRequestId();
    const startTime = Date.now();

    try {
      this.logger.debug("MCP validate request", {
        requestId,
        sessionId: params.sessionId,
      });

      const context = this.createRequestContext(requestId, "auth/validate");
      this.trackRequest(context);

      this.validateValidateParams(params);

      const { sessionId, checkExpiry = true } = params;

      const result = await this.authManager.validateCredentials(sessionId);

      // If not checking expiry, override expired status
      if (!checkExpiry && result.expired) {
        return { ...result, valid: true, expired: false };
      }

      this.updateMetrics("auth/validate", result.valid, Date.now() - startTime);

      this.logger.debug("MCP validate completed", {
        requestId,
        sessionId,
        valid: result.valid,
        duration: Date.now() - startTime,
      });

      return result;
    } catch (error) {
      this.updateMetrics("auth/validate", false, Date.now() - startTime);

      this.logger.error("MCP validate failed", { requestId, error });

      return {
        valid: false,
        error:
          error instanceof Error ? error.message : "Unknown validation error",
      };
    } finally {
      this.untrackRequest(requestId);
    }
  }

  /**
   * Handle additional MCP capabilities
   */
  async handleCapability(method: string, params: any): Promise<any> {
    const requestId = this.generateRequestId();
    const startTime = Date.now();

    try {
      this.logger.debug("MCP capability request", {
        requestId,
        method,
        params: Object.keys(params),
      });

      const context = this.createRequestContext(requestId, method);
      this.trackRequest(context);

      let result: any;

      switch (method) {
        case "auth/revoke":
          result = await this.handleRevoke(params);
          break;
        case "auth/status":
          result = await this.handleStatus(params);
          break;
        case "auth/capabilities":
          result = await this.handleCapabilities(params);
          break;
        case "auth/providers":
          result = await this.handleProviders(params);
          break;
        case "auth/metrics":
          result = await this.handleMetrics(params);
          break;
        default:
          throw this.createMCPError(
            "UNSUPPORTED_METHOD",
            `Unsupported method: ${method}`,
          );
      }

      this.updateMetrics(method, true, Date.now() - startTime);

      this.logger.debug("MCP capability completed", {
        requestId,
        method,
        duration: Date.now() - startTime,
      });

      return result;
    } catch (error) {
      this.updateMetrics(method, false, Date.now() - startTime);

      this.logger.error("MCP capability failed", { requestId, method, error });
      throw error;
    } finally {
      this.untrackRequest(requestId);
    }
  }

  /**
   * Get MCP provider information
   */
  getProviderInfo() {
    return {
      name: this.name,
      version: this.version,
      capabilities: this.capabilities,
      metrics: this.config.enableMetrics ? this.getMetrics() : undefined,
      config: {
        maxConcurrentRequests: this.config.maxConcurrentRequests,
        requestTimeoutMs: this.config.requestTimeoutMs,
        enabledCapabilities: this.config.enabledCapabilities.length,
      },
    };
  }

  /**
   * Handle revocation request
   */
  private async handleRevoke(
    params: any,
  ): Promise<{ success: boolean; error?: string }> {
    try {
      this.validateRevokeParams(params);

      const { sessionId } = params;
      await this.authManager.revokeCredentials(sessionId);

      return { success: true };
    } catch (error) {
      return {
        success: false,
        error:
          error instanceof Error ? error.message : "Unknown revocation error",
      };
    }
  }

  /**
   * Handle status request
   */
  private async handleStatus(params: any): Promise<any> {
    const { sessionId } = params;

    if (sessionId) {
      // Get specific session status
      const session = this.authManager.getSession(sessionId);
      const validation = session
        ? await this.authManager.validateCredentials(sessionId)
        : null;

      return {
        sessionId,
        exists: !!session,
        valid: validation?.valid || false,
        expired: validation?.expired || false,
        session: session
          ? {
              id: session.id,
              status: session.status,
              createdAt: session.createdAt,
              lastActivity: session.lastActivity,
              refreshCount: session.refreshCount,
            }
          : null,
      };
    } else {
      // Get overall auth status
      const activeSessions = this.authManager.getActiveSessions();

      return {
        totalSessions: activeSessions.length,
        activeSessions,
        metrics: this.config.enableMetrics ? this.getMetrics() : null,
      };
    }
  }

  /**
   * Handle capabilities request
   */
  private async handleCapabilities(params: any): Promise<any> {
    return {
      capabilities: this.capabilities,
      version: this.version,
      enabled: this.config.enabledCapabilities,
    };
  }

  /**
   * Handle providers request
   */
  private async handleProviders(params: any): Promise<any> {
    const availableProviders = this.authManager.getAvailableProviders();

    return {
      providers: availableProviders,
      total: availableProviders.length,
    };
  }

  /**
   * Handle metrics request
   */
  private async handleMetrics(params: any): Promise<any> {
    const { includeDetailed = false } = params;

    const baseMetrics = this.getMetrics();

    if (includeDetailed) {
      const authManagerMetrics = this.authManager.getMetrics();

      return {
        mcp: baseMetrics,
        authManager: authManagerMetrics,
        combined: {
          totalRequests:
            baseMetrics.totalRequests + authManagerMetrics.totalAuthentications,
          successRate:
            this.calculateSuccessRate(baseMetrics) +
            authManagerMetrics.successfulAuthentications /
              Math.max(authManagerMetrics.totalAuthentications, 1),
          activeContexts: authManagerMetrics.activeContexts,
        },
      };
    }

    return baseMetrics;
  }

  /**
   * Get metrics
   */
  private getMetrics(): MCPAuthMetrics {
    return {
      ...this.metrics,
      activeRequests: this.activeRequests.size,
    };
  }

  /**
   * Calculate success rate
   */
  private calculateSuccessRate(metrics: MCPAuthMetrics): number {
    const total = metrics.totalRequests;
    return total > 0 ? (metrics.successfulRequests / total) * 100 : 0;
  }

  /**
   * Track active request
   */
  private trackRequest(context: MCPRequestContext): void {
    this.activeRequests.set(context.requestId, context);

    // Set timeout
    context.timeout = setTimeout(() => {
      this.handleRequestTimeout(context.requestId);
    }, this.config.requestTimeoutMs);
  }

  /**
   * Untrack request
   */
  private untrackRequest(requestId: string): void {
    const context = this.activeRequests.get(requestId);
    if (context?.timeout) {
      clearTimeout(context.timeout);
    }
    this.activeRequests.delete(requestId);
  }

  /**
   * Handle request timeout
   */
  private handleRequestTimeout(requestId: string): void {
    const context = this.activeRequests.get(requestId);
    if (context) {
      this.logger.warn("MCP request timeout", {
        requestId,
        method: context.method,
        duration: Date.now() - context.timestamp,
      });

      this.updateMetrics(context.method, false, Date.now() - context.timestamp);
      this.activeRequests.delete(requestId);
    }
  }

  /**
   * Update metrics
   */
  private updateMetrics(
    method: string,
    success: boolean,
    responseTime: number,
  ): void {
    if (!this.config.enableMetrics) return;

    this.metrics.totalRequests++;

    if (success) {
      this.metrics.successfulRequests++;
    } else {
      this.metrics.failedRequests++;
    }

    // Update average response time
    const totalTime =
      this.metrics.averageResponseTime * (this.metrics.totalRequests - 1) +
      responseTime;
    this.metrics.averageResponseTime = totalTime / this.metrics.totalRequests;

    // Update capability usage
    this.metrics.capabilityUsage[method] =
      (this.metrics.capabilityUsage[method] || 0) + 1;
  }

  /**
   * Create request context
   */
  private createRequestContext(
    requestId: string,
    method: string,
  ): MCPRequestContext {
    return {
      requestId,
      method,
      timestamp: Date.now(),
    };
  }

  /**
   * Generate unique request ID
   */
  private generateRequestId(): string {
    return `mcp_${Date.now()}_${++this.requestCounter}`;
  }

  /**
   * Parameter validation methods
   */
  private validateAuthenticateParams(params: any): void {
    if (!params.provider) {
      throw this.createMCPError("INVALID_PARAMS", "Provider is required");
    }
  }

  private validateRefreshParams(params: any): void {
    if (!params.sessionId) {
      throw this.createMCPError("INVALID_PARAMS", "Session ID is required");
    }
  }

  private validateValidateParams(params: any): void {
    if (!params.sessionId) {
      throw this.createMCPError("INVALID_PARAMS", "Session ID is required");
    }
  }

  private validateRevokeParams(params: any): void {
    if (!params.sessionId) {
      throw this.createMCPError("INVALID_PARAMS", "Session ID is required");
    }
  }

  /**
   * Create MCP-specific error
   */
  private createMCPError(code: string, message: string): Error {
    const error = new Error(message);
    (error as any).code = code;
    (error as any).type = "mcp_error";
    return error;
  }

  /**
   * Create auth error
   */
  private createAuthError(
    code: string,
    message: string,
    originalError?: Error,
  ): AuthError {
    const error = new Error(message) as AuthError;
    error.code = code;
    error.type = "authentication";
    error.retryable = false;
    error.originalError = originalError;
    error.context = {
      provider: this.name,
      source: "mcp",
      timestamp: Date.now(),
    };
    return error;
  }
}