@clduab11/gemini-flow/src/performance/edge-cache-optimizer.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.

/**
 * Edge Cache Optimizer - Advanced CDN and cache warming strategies
 * Implements predictive pre-loading and intelligent cache invalidation
 */

import { EventEmitter } from "events";

export interface CacheNode {
  id: string;
  location: {
    region: string;
    city: string;
    coordinates: { lat: number; lng: number };
  };
  capacity: number; // bytes
  used: number;
  hitRate: number;
  latency: number;
  bandwidth: number;
  status: "online" | "offline" | "maintenance";
  temperature: "cold" | "warm" | "hot";
  tier: "edge" | "regional" | "origin";
}

export interface CacheItem {
  key: string;
  content: ArrayBuffer;
  size: number;
  contentType: string;
  createdAt: number;
  lastAccessed: number;
  accessCount: number;
  ttl: number;
  tags: string[];
  priority: number;
  metadata: {
    userId?: string;
    region?: string;
    contentHash: string;
    compression: "none" | "gzip" | "brotli";
  };
}

export interface CachePolicy {
  maxAge: number;
  staleWhileRevalidate: number;
  staleIfError: number;
  mustRevalidate: boolean;
  noCache: boolean;
  private: boolean;
  public: boolean;
  immutable: boolean;
}

export interface WarmingStrategy {
  type: "predictive" | "scheduled" | "reactive" | "manual";
  triggers: Array<{
    event: string;
    condition: string;
    priority: number;
  }>;
  contentSelectors: string[];
  targetNodes: string[];
  schedule?: string; // cron expression
}

export interface CDNMetrics {
  hitRate: number;
  missRate: number;
  bandwidth: number;
  latency: number;
  errorRate: number;
  cacheSize: number;
  requestsPerSecond: number;
  bytesSaved: number;
  costSavings: number;
}

export class EdgeCacheOptimizer extends EventEmitter {
  private nodes: Map<string, CacheNode> = new Map();
  private cache: Map<string, Map<string, CacheItem>> = new Map(); // nodeId -> cache
  private policies: Map<string, CachePolicy> = new Map();
  private warmingStrategies: WarmingStrategy[] = [];
  private predictor: CachePredictionEngine;
  private invalidator: CacheInvalidationManager;
  private loadBalancer: CDNLoadBalancer;
  private compressionManager: CompressionManager;
  private analyticsEngine: CacheAnalyticsEngine;

  constructor() {
    super();
    this.predictor = new CachePredictionEngine();
    this.invalidator = new CacheInvalidationManager();
    this.loadBalancer = new CDNLoadBalancer();
    this.compressionManager = new CompressionManager();
    this.analyticsEngine = new CacheAnalyticsEngine();
    this.initializeOptimizer();
  }

  /**
   * Register cache node in the CDN network
   */
  registerNode(node: CacheNode): void {
    this.nodes.set(node.id, node);
    this.cache.set(node.id, new Map());
    this.loadBalancer.addNode(node);

    this.emit("nodeRegistered", { nodeId: node.id, location: node.location });
    console.log(`Registered cache node: ${node.id} in ${node.location.city}`);
  }

  /**
   * Cache content with intelligent placement
   */
  async cacheContent(
    key: string,
    content: ArrayBuffer,
    contentType: string,
    policy: CachePolicy,
    targetNodes?: string[],
  ): Promise<{
    cached: string[];
    failed: string[];
    totalSize: number;
  }> {
    const item: CacheItem = {
      key,
      content,
      size: content.byteLength,
      contentType,
      createdAt: Date.now(),
      lastAccessed: Date.now(),
      accessCount: 1,
      ttl: policy.maxAge,
      tags: [],
      priority: this.calculatePriority(key, content),
      metadata: {
        contentHash: await this.calculateHash(content),
        compression: "none",
      },
    };

    // Compress if beneficial
    const compressed = await this.compressionManager.compress(item);
    if (compressed.size < item.size * 0.8) {
      // 20% compression threshold
      item.content = compressed.content;
      item.size = compressed.size;
      item.metadata.compression = compressed.algorithm;
    }

    const optimalNodes = targetNodes || (await this.selectOptimalNodes(item));
    const cached: string[] = [];
    const failed: string[] = [];

    for (const nodeId of optimalNodes) {
      try {
        await this.cacheOnNode(nodeId, item, policy);
        cached.push(nodeId);
      } catch (error) {
        failed.push(nodeId);
        console.error(`Failed to cache on node ${nodeId}:`, error.message);
      }
    }

    this.emit("contentCached", { key, cached, failed, size: item.size });
    return { cached, failed, totalSize: item.size };
  }

  /**
   * Retrieve content from optimal cache node
   */
  async getContent(
    key: string,
    userLocation?: {
      lat: number;
      lng: number;
    },
  ): Promise<{
    content: ArrayBuffer | null;
    source: string;
    latency: number;
    cacheHit: boolean;
  }> {
    const startTime = Date.now();

    // Find optimal node for user location
    const optimalNode = userLocation
      ? this.findNearestNode(userLocation)
      : this.loadBalancer.selectNode();

    if (!optimalNode) {
      return {
        content: null,
        source: "none",
        latency: Date.now() - startTime,
        cacheHit: false,
      };
    }

    const nodeCache = this.cache.get(optimalNode.id);
    const item = nodeCache?.get(key);

    if (item && !this.isExpired(item)) {
      // Cache hit
      item.lastAccessed = Date.now();
      item.accessCount++;

      // Decompress if needed
      const content = await this.decompress(item);

      this.emit("cacheHit", { key, nodeId: optimalNode.id });
      return {
        content,
        source: optimalNode.id,
        latency: Date.now() - startTime,
        cacheHit: true,
      };
    } else {
      // Cache miss - try other nodes or fetch from origin
      const fallbackResult = await this.handleCacheMiss(key, optimalNode);

      this.emit("cacheMiss", { key, nodeId: optimalNode.id });
      return {
        ...fallbackResult,
        latency: Date.now() - startTime,
        cacheHit: false,
      };
    }
  }

  /**
   * Implement predictive cache warming
   */
  async warmCache(strategy: WarmingStrategy): Promise<{
    itemsWarmed: number;
    nodesUpdated: string[];
    dataTransferred: number;
    estimatedHitRateImprovement: number;
  }> {
    this.warmingStrategies.push(strategy);

    let itemsWarmed = 0;
    let dataTransferred = 0;
    const nodesUpdated = new Set<string>();

    switch (strategy.type) {
      case "predictive":
        const predictions = await this.predictor.predictContent(
          strategy.contentSelectors,
          strategy.targetNodes,
        );

        for (const prediction of predictions) {
          if (prediction.confidence > 0.7) {
            // 70% confidence threshold
            const result = await this.preloadContent(prediction);
            itemsWarmed += result.itemsLoaded;
            dataTransferred += result.dataSize;
            result.nodes.forEach((node) => nodesUpdated.add(node));
          }
        }
        break;

      case "scheduled":
        // Schedule warming based on cron expression
        if (strategy.schedule) {
          this.scheduleWarming(strategy);
        }
        break;

      case "reactive":
        // Warm based on real-time events
        this.setupReactiveWarming(strategy);
        break;
    }

    const estimatedImprovement =
      this.analyticsEngine.estimateHitRateImprovement(
        itemsWarmed,
        dataTransferred,
      );

    this.emit("cacheWarmed", {
      strategy: strategy.type,
      itemsWarmed,
      nodesUpdated: Array.from(nodesUpdated),
      dataTransferred,
      estimatedImprovement,
    });

    return {
      itemsWarmed,
      nodesUpdated: Array.from(nodesUpdated),
      dataTransferred,
      estimatedHitRateImprovement: estimatedImprovement,
    };
  }

  /**
   * Intelligent cache invalidation
   */
  async invalidateContent(
    pattern: string | RegExp,
    tags?: string[],
    cascading: boolean = true,
  ): Promise<{
    invalidated: number;
    nodesAffected: string[];
    spaceFree: number;
  }> {
    let invalidated = 0;
    let spaceFree = 0;
    const nodesAffected = new Set<string>();

    for (const [nodeId, nodeCache] of this.cache.entries()) {
      const keysToInvalidate: string[] = [];

      for (const [key, item] of nodeCache.entries()) {
        let shouldInvalidate = false;

        // Pattern matching
        if (typeof pattern === "string") {
          shouldInvalidate = key.includes(pattern);
        } else {
          shouldInvalidate = pattern.test(key);
        }

        // Tag matching
        if (tags && tags.length > 0) {
          shouldInvalidate =
            shouldInvalidate || tags.some((tag) => item.tags.includes(tag));
        }

        if (shouldInvalidate) {
          keysToInvalidate.push(key);
        }
      }

      for (const key of keysToInvalidate) {
        const item = nodeCache.get(key);
        if (item) {
          nodeCache.delete(key);
          invalidated++;
          spaceFree += item.size;
          nodesAffected.add(nodeId);

          // Cascading invalidation
          if (cascading) {
            await this.invalidator.cascadeInvalidation(key, item);
          }
        }
      }
    }

    this.emit("contentInvalidated", {
      pattern: pattern.toString(),
      invalidated,
      nodesAffected: Array.from(nodesAffected),
      spaceFree,
    });

    return {
      invalidated,
      nodesAffected: Array.from(nodesAffected),
      spaceFree,
    };
  }

  /**
   * Optimize cache distribution across nodes
   */
  async optimizeDistribution(): Promise<{
    migrations: number;
    dataTransferred: number;
    expectedHitRateImprovement: number;
    costSavings: number;
  }> {
    const analysis = await this.analyticsEngine.analyzeDistribution(
      this.nodes,
      this.cache,
    );

    let migrations = 0;
    let dataTransferred = 0;

    for (const recommendation of analysis.recommendations) {
      switch (recommendation.type) {
        case "migrate":
          await this.migrateContent(
            recommendation.sourceNode,
            recommendation.targetNode,
            recommendation.contentKeys,
          );
          migrations += recommendation.contentKeys.length;
          dataTransferred += recommendation.dataSize;
          break;

        case "replicate":
          await this.replicateContent(
            recommendation.sourceNode,
            recommendation.targetNodes,
            recommendation.contentKeys,
          );
          break;

        case "evict":
          await this.evictContent(
            recommendation.sourceNode,
            recommendation.contentKeys,
          );
          break;
      }
    }

    this.emit("distributionOptimized", {
      migrations,
      dataTransferred,
      expectedImprovement: analysis.expectedImprovement,
      costSavings: analysis.costSavings,
    });

    return {
      migrations,
      dataTransferred,
      expectedHitRateImprovement: analysis.expectedImprovement,
      costSavings: analysis.costSavings,
    };
  }

  /**
   * Get comprehensive CDN metrics
   */
  getCDNMetrics(): CDNMetrics {
    const allNodes = Array.from(this.nodes.values());
    const allCaches = Array.from(this.cache.values());

    let totalHits = 0;
    let totalMisses = 0;
    let totalSize = 0;
    let totalRequests = 0;

    for (const nodeCache of allCaches) {
      for (const item of nodeCache.values()) {
        totalRequests += item.accessCount;
        totalSize += item.size;
        // Simplified hit/miss calculation
        totalHits += Math.floor(item.accessCount * 0.8);
        totalMisses += Math.ceil(item.accessCount * 0.2);
      }
    }

    const hitRate = totalRequests > 0 ? totalHits / totalRequests : 0;
    const missRate = 1 - hitRate;
    const avgLatency =
      allNodes.reduce((sum, node) => sum + node.latency, 0) / allNodes.length;
    const totalBandwidth = allNodes.reduce(
      (sum, node) => sum + node.bandwidth,
      0,
    );

    return {
      hitRate,
      missRate,
      bandwidth: totalBandwidth,
      latency: avgLatency,
      errorRate: 0.01, // Simulated
      cacheSize: totalSize,
      requestsPerSecond: totalRequests / 3600, // Approximation
      bytesSaved: totalSize * hitRate,
      costSavings: totalSize * hitRate * 0.0001, // $0.0001 per byte saved
    };
  }

  /**
   * Configure CDN policy for content types
   */
  setPolicy(contentPattern: string, policy: CachePolicy): void {
    this.policies.set(contentPattern, policy);
    this.emit("policySet", { pattern: contentPattern, policy });
  }

  // Private implementation methods

  private async initializeOptimizer(): Promise<void> {
    // Setup default policies
    this.setupDefaultPolicies();

    // Start background optimization
    this.startBackgroundOptimization();

    this.emit("optimizerInitialized");
  }

  private setupDefaultPolicies(): void {
    const defaultPolicies = [
      {
        pattern: "image/*",
        policy: {
          maxAge: 86400, // 24 hours
          staleWhileRevalidate: 3600,
          staleIfError: 86400,
          mustRevalidate: false,
          noCache: false,
          private: false,
          public: true,
          immutable: true,
        },
      },
      {
        pattern: "video/*",
        policy: {
          maxAge: 604800, // 7 days
          staleWhileRevalidate: 86400,
          staleIfError: 604800,
          mustRevalidate: false,
          noCache: false,
          private: false,
          public: true,
          immutable: true,
        },
      },
      {
        pattern: "application/json",
        policy: {
          maxAge: 300, // 5 minutes
          staleWhileRevalidate: 60,
          staleIfError: 3600,
          mustRevalidate: true,
          noCache: false,
          private: false,
          public: true,
          immutable: false,
        },
      },
    ];

    for (const { pattern, policy } of defaultPolicies) {
      this.setPolicy(pattern, policy);
    }
  }

  private async selectOptimalNodes(item: CacheItem): Promise<string[]> {
    const nodes = Array.from(this.nodes.values())
      .filter((node) => node.status === "online")
      .sort((a, b) => {
        // Score based on capacity, latency, and current load
        const scoreA =
          (1 - a.used / a.capacity) * 0.5 +
          (1 / a.latency) * 0.3 +
          a.hitRate * 0.2;
        const scoreB =
          (1 - b.used / b.capacity) * 0.5 +
          (1 / b.latency) * 0.3 +
          b.hitRate * 0.2;
        return scoreB - scoreA;
      });

    // Select top 3 nodes for redundancy
    return nodes.slice(0, 3).map((node) => node.id);
  }

  private async cacheOnNode(
    nodeId: string,
    item: CacheItem,
    policy: CachePolicy,
  ): Promise<void> {
    const node = this.nodes.get(nodeId);
    const nodeCache = this.cache.get(nodeId);

    if (!node || !nodeCache) {
      throw new Error(`Node ${nodeId} not found`);
    }

    // Check capacity
    if (node.used + item.size > node.capacity) {
      await this.evictLRU(nodeId, item.size);
    }

    // Store item
    nodeCache.set(item.key, { ...item });
    node.used += item.size;

    this.policies.set(item.key, policy);
  }

  private findNearestNode(userLocation: {
    lat: number;
    lng: number;
  }): CacheNode | null {
    let nearest: CacheNode | null = null;
    let minDistance = Infinity;

    for (const node of this.nodes.values()) {
      if (node.status !== "online") continue;

      const distance = this.calculateDistance(
        userLocation,
        node.location.coordinates,
      );

      if (distance < minDistance) {
        minDistance = distance;
        nearest = node;
      }
    }

    return nearest;
  }

  private calculateDistance(
    point1: { lat: number; lng: number },
    point2: { lat: number; lng: number },
  ): number {
    const R = 6371; // Earth's radius in km
    const dLat = ((point2.lat - point1.lat) * Math.PI) / 180;
    const dLng = ((point2.lng - point1.lng) * Math.PI) / 180;
    const a =
      Math.sin(dLat / 2) * Math.sin(dLat / 2) +
      Math.cos((point1.lat * Math.PI) / 180) *
        Math.cos((point2.lat * Math.PI) / 180) *
        Math.sin(dLng / 2) *
        Math.sin(dLng / 2);
    const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    return R * c;
  }

  private isExpired(item: CacheItem): boolean {
    return Date.now() > item.createdAt + item.ttl;
  }

  private async decompress(item: CacheItem): Promise<ArrayBuffer> {
    if (item.metadata.compression === "none") {
      return item.content;
    }

    return this.compressionManager.decompress(
      item.content,
      item.metadata.compression,
    );
  }

  private async handleCacheMiss(
    key: string,
    preferredNode: CacheNode,
  ): Promise<{
    content: ArrayBuffer | null;
    source: string;
  }> {
    // Try other nodes
    for (const [nodeId, nodeCache] of this.cache.entries()) {
      if (nodeId === preferredNode.id) continue;

      const item = nodeCache.get(key);
      if (item && !this.isExpired(item)) {
        const content = await this.decompress(item);

        // Replicate to preferred node for future requests
        this.cacheOnNode(
          preferredNode.id,
          item,
          this.policies.get(key) || this.getDefaultPolicy(),
        );

        return { content, source: nodeId };
      }
    }

    // Fetch from origin (simulated)
    return { content: null, source: "origin" };
  }

  private async preloadContent(prediction: any): Promise<{
    itemsLoaded: number;
    dataSize: number;
    nodes: string[];
  }> {
    // Simulate content preloading
    return {
      itemsLoaded: Math.floor(Math.random() * 10) + 1,
      dataSize: Math.floor(Math.random() * 1000000) + 100000,
      nodes: prediction.targetNodes,
    };
  }

  private scheduleWarming(strategy: WarmingStrategy): void {
    // Schedule cache warming using cron-like scheduling
    // Implementation would use a proper scheduler
  }

  private setupReactiveWarming(strategy: WarmingStrategy): void {
    // Setup event-driven cache warming
    for (const trigger of strategy.triggers) {
      this.on(trigger.event, async () => {
        if (this.evaluateCondition(trigger.condition)) {
          await this.warmCache(strategy);
        }
      });
    }
  }

  private evaluateCondition(condition: string): boolean {
    // Evaluate warming condition
    return true; // Simplified
  }

  private async migrateContent(
    sourceNode: string,
    targetNode: string,
    contentKeys: string[],
  ): Promise<void> {
    const sourceCache = this.cache.get(sourceNode);
    const targetCache = this.cache.get(targetNode);

    if (!sourceCache || !targetCache) return;

    for (const key of contentKeys) {
      const item = sourceCache.get(key);
      if (item) {
        targetCache.set(key, { ...item });
        sourceCache.delete(key);
      }
    }
  }

  private async replicateContent(
    sourceNode: string,
    targetNodes: string[],
    contentKeys: string[],
  ): Promise<void> {
    const sourceCache = this.cache.get(sourceNode);
    if (!sourceCache) return;

    for (const targetNode of targetNodes) {
      const targetCache = this.cache.get(targetNode);
      if (!targetCache) continue;

      for (const key of contentKeys) {
        const item = sourceCache.get(key);
        if (item) {
          targetCache.set(key, { ...item });
        }
      }
    }
  }

  private async evictContent(
    nodeId: string,
    contentKeys: string[],
  ): Promise<void> {
    const nodeCache = this.cache.get(nodeId);
    if (!nodeCache) return;

    for (const key of contentKeys) {
      nodeCache.delete(key);
    }
  }

  private async evictLRU(nodeId: string, requiredSpace: number): Promise<void> {
    const nodeCache = this.cache.get(nodeId);
    const node = this.nodes.get(nodeId);

    if (!nodeCache || !node) return;

    const items = Array.from(nodeCache.entries())
      .map(([key, item]) => ({ key, item }))
      .sort((a, b) => a.item.lastAccessed - b.item.lastAccessed);

    let freedSpace = 0;
    const toEvict: string[] = [];

    for (const { key, item } of items) {
      toEvict.push(key);
      freedSpace += item.size;

      if (freedSpace >= requiredSpace) break;
    }

    for (const key of toEvict) {
      const item = nodeCache.get(key);
      if (item) {
        nodeCache.delete(key);
        node.used -= item.size;
      }
    }
  }

  private calculatePriority(key: string, content: ArrayBuffer): number {
    // Calculate content priority based on various factors
    const sizeFactor = Math.max(0, 1 - content.byteLength / (10 * 1024 * 1024)); // Prefer smaller content
    const typeFactor = key.includes("image")
      ? 0.8
      : key.includes("video")
        ? 0.6
        : 1.0;

    return sizeFactor * typeFactor * 100;
  }

  private async calculateHash(content: ArrayBuffer): Promise<string> {
    // Calculate content hash for integrity verification
    const buffer = new Uint8Array(content);
    let hash = 0;
    for (let i = 0; i < buffer.length; i++) {
      hash = ((hash << 5) - hash + buffer[i]) & 0xffffffff;
    }
    return hash.toString(16);
  }

  private getDefaultPolicy(): CachePolicy {
    return {
      maxAge: 3600,
      staleWhileRevalidate: 300,
      staleIfError: 3600,
      mustRevalidate: false,
      noCache: false,
      private: false,
      public: true,
      immutable: false,
    };
  }

  private startBackgroundOptimization(): void {
    // Periodic optimization tasks
    setInterval(() => {
      this.optimizeDistribution();
    }, 300000); // Every 5 minutes

    setInterval(() => {
      this.cleanupExpiredContent();
    }, 60000); // Every minute
  }

  private cleanupExpiredContent(): void {
    for (const [nodeId, nodeCache] of this.cache.entries()) {
      const expiredKeys: string[] = [];

      for (const [key, item] of nodeCache.entries()) {
        if (this.isExpired(item)) {
          expiredKeys.push(key);
        }
      }

      for (const key of expiredKeys) {
        nodeCache.delete(key);
      }
    }
  }
}

// Supporting classes
class CachePredictionEngine {
  async predictContent(
    selectors: string[],
    targetNodes: string[],
  ): Promise<any[]> {
    // Predict content that should be cached
    return [];
  }
}

class CacheInvalidationManager {
  async cascadeInvalidation(key: string, item: CacheItem): Promise<void> {
    // Handle cascading invalidation
  }
}

class CDNLoadBalancer {
  addNode(node: CacheNode): void {
    // Add node to load balancer
  }

  selectNode(): CacheNode | null {
    // Select optimal node for request
    return null;
  }
}

class CompressionManager {
  async compress(item: CacheItem): Promise<{
    content: ArrayBuffer;
    size: number;
    algorithm: "gzip" | "brotli";
  }> {
    // Compress content
    return {
      content: item.content,
      size: Math.floor(item.size * 0.7), // Simulate 30% compression
      algorithm: "gzip",
    };
  }

  async decompress(
    content: ArrayBuffer,
    algorithm: string,
  ): Promise<ArrayBuffer> {
    // Decompress content
    return content;
  }
}

class CacheAnalyticsEngine {
  async analyzeDistribution(
    nodes: Map<string, CacheNode>,
    cache: Map<string, Map<string, CacheItem>>,
  ): Promise<{
    recommendations: any[];
    expectedImprovement: number;
    costSavings: number;
  }> {
    return {
      recommendations: [],
      expectedImprovement: 0.1,
      costSavings: 1000,
    };
  }

  estimateHitRateImprovement(
    itemsWarmed: number,
    dataTransferred: number,
  ): number {
    return Math.min(0.2, itemsWarmed * 0.01); // Max 20% improvement
  }
}

export {
  CachePredictionEngine,
  CacheInvalidationManager,
  CDNLoadBalancer,
  CompressionManager,
  CacheAnalyticsEngine,
};