// Cache Service - Redis Integration
// Caches RPC responses and risk calculations

import { logger } from '@/infrastructure/monitoring/logger';

// Placeholder for Redis client
interface RedisClient {
  get: (key: string) => Promise<string | null>;
  set: (key: string, value: string, ttl?: number) => Promise<void>;
  del: (key: string) => Promise<void>;
  exists: (key: string) => Promise<number>;
}

export interface CacheConfig {
  enabled: boolean;
  defaultTtl: number; // seconds
  priceDataTtl: number;
  riskCalcTtl: number;
  exchangeRateTtl: number;
}

export class CacheService {
  private redis: RedisClient | null = null;
  private config: CacheConfig = {
    enabled: process.env.REDIS_ENABLED === 'true',
    defaultTtl: 300, // 5 minutes
    priceDataTtl: 60, // 1 minute
    riskCalcTtl: 300, // 5 minutes
    exchangeRateTtl: 30, // 30 seconds
  };

  constructor(redisClient?: RedisClient) {
    if (redisClient) {
      this.redis = redisClient;
    } else if (this.config.enabled) {
      // TODO: Initialize Redis client
      // this.redis = new Redis(process.env.REDIS_URL || 'redis://localhost:6379');
      logger.warn('Redis client not initialized - caching disabled');
      this.config.enabled = false;
    }
  }

  /**
   * Get cached value
   */
  async get<T>(key: string): Promise<T | null> {
    if (!this.config.enabled || !this.redis) {
      return null;
    }

    try {
      const value = await this.redis.get(key);
      if (value) {
        return JSON.parse(value) as T;
      }
      return null;
    } catch (error) {
      logger.error('Cache get error', { key, error });
      return null;
    }
  }

  /**
   * Set cached value
   */
  async set(key: string, value: any, ttl?: number): Promise<void> {
    if (!this.config.enabled || !this.redis) {
      return;
    }

    try {
      const serialized = JSON.stringify(value);
      await this.redis.set(key, serialized, ttl || this.config.defaultTtl);
    } catch (error) {
      logger.error('Cache set error', { key, error });
    }
  }

  /**
   * Delete cached value
   */
  async delete(key: string): Promise<void> {
    if (!this.config.enabled || !this.redis) {
      return;
    }

    try {
      await this.redis.del(key);
    } catch (error) {
      logger.error('Cache delete error', { key, error });
    }
  }

  /**
   * Get cached price
   */
  async getCachedPrice(tokenAddress: string): Promise<string | null> {
    return this.get<string>(`price:${tokenAddress}`);
  }

  /**
   * Set cached price
   */
  async setCachedPrice(tokenAddress: string, price: string): Promise<void> {
    await this.set(`price:${tokenAddress}`, price, this.config.priceDataTtl);
  }

  /**
   * Get cached exchange rate
   */
  async getCachedExchangeRate(from: string, to: string): Promise<string | null> {
    return this.get<string>(`rate:${from}:${to}`);
  }

  /**
   * Set cached exchange rate
   */
  async setCachedExchangeRate(from: string, to: string, rate: string): Promise<void> {
    await this.set(`rate:${from}:${to}`, rate, this.config.exchangeRateTtl);
  }

  /**
   * Get cached risk calculation
   */
  async getCachedRiskCalc(dealId: string, calcType: string): Promise<any | null> {
    return this.get(`risk:${dealId}:${calcType}`);
  }

  /**
   * Set cached risk calculation
   */
  async setCachedRiskCalc(dealId: string, calcType: string, result: any): Promise<void> {
    await this.set(`risk:${dealId}:${calcType}`, result, this.config.riskCalcTtl);
  }

  /**
   * Invalidate deal cache
   */
  async invalidateDealCache(dealId: string): Promise<void> {
    const patterns = [
      `risk:${dealId}:*`,
      `deal:${dealId}:*`,
    ];

    // TODO: Implement pattern-based deletion if needed
    logger.debug('Deal cache invalidated', { dealId });
  }
}

export const cacheService = new CacheService();