import * as plugins from '../plugins.js';
import type { IStockProvider, IProviderConfig } from './interfaces/provider.js';
import type { IFundamentalsProvider, IFundamentalsProviderConfig, IStockFundamentals } from './interfaces/fundamentals.js';
import type { IStockPrice, IStockDataRequest as IPriceRequest } from './interfaces/stockprice.js';
import type { IStockData, IStockDataServiceConfig, ICompleteStockDataRequest, ICompleteStockDataBatchRequest } from './interfaces/stockdata.js';

interface IProviderEntry<T> {
  provider: T;
  config: IProviderConfig | IFundamentalsProviderConfig;
  lastError?: Error;
  lastErrorTime?: Date;
  successCount: number;
  errorCount: number;
}

interface ICacheEntry<T> {
  data: T;
  timestamp: Date;
  ttl: number;
}

/**
 * Unified service for managing both stock prices and fundamentals
 * Provides automatic enrichment and convenient combined data access
 */
export class StockDataService {
  private priceProviders = new Map<string, IProviderEntry<IStockProvider>>();
  private fundamentalsProviders = new Map<string, IProviderEntry<IFundamentalsProvider>>();

  private priceCache = new Map<string, ICacheEntry<IStockPrice | IStockPrice[]>>();
  private fundamentalsCache = new Map<string, ICacheEntry<IStockFundamentals | IStockFundamentals[]>>();

  private logger = console;

  private config: Required<IStockDataServiceConfig> = {
    cache: {
      priceTTL: 24 * 60 * 60 * 1000, // 24 hours
      fundamentalsTTL: 90 * 24 * 60 * 60 * 1000, // 90 days
      maxEntries: 10000
    },
    timeout: {
      price: 10000, // 10 seconds
      fundamentals: 30000 // 30 seconds
    }
  };

  constructor(config?: IStockDataServiceConfig) {
    if (config) {
      this.config = {
        cache: { ...this.config.cache, ...config.cache },
        timeout: { ...this.config.timeout, ...config.timeout }
      };
    }
  }

  // ========== Provider Management ==========

  /**
   * Register a price provider
   */
  public registerPriceProvider(provider: IStockProvider, config?: IProviderConfig): void {
    const defaultConfig: IProviderConfig = {
      enabled: true,
      priority: provider.priority,
      timeout: this.config.timeout.price,
      retryAttempts: 2,
      retryDelay: 1000
    };

    const mergedConfig = { ...defaultConfig, ...config };

    this.priceProviders.set(provider.name, {
      provider,
      config: mergedConfig,
      successCount: 0,
      errorCount: 0
    });

    console.log(`Registered price provider: ${provider.name}`);
  }

  /**
   * Register a fundamentals provider
   */
  public registerFundamentalsProvider(
    provider: IFundamentalsProvider,
    config?: IFundamentalsProviderConfig
  ): void {
    const defaultConfig: IFundamentalsProviderConfig = {
      enabled: true,
      priority: provider.priority,
      timeout: this.config.timeout.fundamentals,
      retryAttempts: 2,
      retryDelay: 1000,
      cacheTTL: this.config.cache.fundamentalsTTL
    };

    const mergedConfig = { ...defaultConfig, ...config };

    this.fundamentalsProviders.set(provider.name, {
      provider,
      config: mergedConfig,
      successCount: 0,
      errorCount: 0
    });

    console.log(`Registered fundamentals provider: ${provider.name}`);
  }

  /**
   * Unregister a price provider
   */
  public unregisterPriceProvider(providerName: string): void {
    this.priceProviders.delete(providerName);
    console.log(`Unregistered price provider: ${providerName}`);
  }

  /**
   * Unregister a fundamentals provider
   */
  public unregisterFundamentalsProvider(providerName: string): void {
    this.fundamentalsProviders.delete(providerName);
    console.log(`Unregistered fundamentals provider: ${providerName}`);
  }

  /**
   * Get all registered price providers
   */
  public getPriceProviders(): IStockProvider[] {
    return Array.from(this.priceProviders.values()).map(entry => entry.provider);
  }

  /**
   * Get all registered fundamentals providers
   */
  public getFundamentalsProviders(): IFundamentalsProvider[] {
    return Array.from(this.fundamentalsProviders.values()).map(entry => entry.provider);
  }

  /**
   * Get enabled price providers sorted by priority
   */
  private getEnabledPriceProviders(): IStockProvider[] {
    return Array.from(this.priceProviders.values())
      .filter(entry => entry.config.enabled)
      .sort((a, b) => (b.config.priority || 0) - (a.config.priority || 0))
      .map(entry => entry.provider);
  }

  /**
   * Get enabled fundamentals providers sorted by priority
   */
  private getEnabledFundamentalsProviders(): IFundamentalsProvider[] {
    return Array.from(this.fundamentalsProviders.values())
      .filter(entry => entry.config.enabled)
      .sort((a, b) => (b.config.priority || 0) - (a.config.priority || 0))
      .map(entry => entry.provider);
  }

  // ========== Data Fetching Methods ==========

  /**
   * Get current price for a single ticker
   */
  public async getPrice(ticker: string): Promise<IStockPrice> {
    const cacheKey = `price:${ticker}`;
    const cached = this.getFromCache(this.priceCache, cacheKey);

    if (cached) {
      console.log(`Cache hit for price: ${ticker}`);
      return cached as IStockPrice;
    }

    const providers = this.getEnabledPriceProviders();
    if (providers.length === 0) {
      throw new Error('No price providers available');
    }

    let lastError: Error | undefined;

    for (const provider of providers) {
      const entry = this.priceProviders.get(provider.name)!;

      try {
        const result = await this.fetchWithRetry(
          () => provider.fetchData({ type: 'current', ticker }),
          entry.config
        );

        entry.successCount++;

        const price = result as IStockPrice;
        this.addToCache(this.priceCache, cacheKey, price, this.config.cache.priceTTL);

        console.log(`Successfully fetched price for ${ticker} from ${provider.name}`);
        return price;
      } catch (error) {
        entry.errorCount++;
        entry.lastError = error as Error;
        entry.lastErrorTime = new Date();
        lastError = error as Error;

        console.warn(`Provider ${provider.name} failed for ${ticker}: ${error.message}`);
      }
    }

    throw new Error(
      `Failed to fetch price for ${ticker} from all providers. Last error: ${lastError?.message}`
    );
  }

  /**
   * Get current prices for multiple tickers
   */
  public async getPrices(tickers: string[]): Promise<IStockPrice[]> {
    const cacheKey = `prices:${tickers.sort().join(',')}`;
    const cached = this.getFromCache(this.priceCache, cacheKey);

    if (cached) {
      console.log(`Cache hit for prices: ${tickers.length} tickers`);
      return cached as IStockPrice[];
    }

    const providers = this.getEnabledPriceProviders();
    if (providers.length === 0) {
      throw new Error('No price providers available');
    }

    let lastError: Error | undefined;

    for (const provider of providers) {
      const entry = this.priceProviders.get(provider.name)!;

      try {
        const result = await this.fetchWithRetry(
          () => provider.fetchData({ type: 'batch', tickers }),
          entry.config
        );

        entry.successCount++;

        const prices = result as IStockPrice[];
        this.addToCache(this.priceCache, cacheKey, prices, this.config.cache.priceTTL);

        console.log(`Successfully fetched ${prices.length} prices from ${provider.name}`);
        return prices;
      } catch (error) {
        entry.errorCount++;
        entry.lastError = error as Error;
        entry.lastErrorTime = new Date();
        lastError = error as Error;

        console.warn(`Provider ${provider.name} failed for batch prices: ${error.message}`);
      }
    }

    throw new Error(
      `Failed to fetch prices for ${tickers.length} tickers from all providers. Last error: ${lastError?.message}`
    );
  }

  /**
   * Get fundamentals for a single ticker
   */
  public async getFundamentals(ticker: string): Promise<IStockFundamentals> {
    const cacheKey = `fundamentals:${ticker}`;
    const cached = this.getFromCache(this.fundamentalsCache, cacheKey);

    if (cached) {
      console.log(`Cache hit for fundamentals: ${ticker}`);
      return cached as IStockFundamentals;
    }

    const providers = this.getEnabledFundamentalsProviders();
    if (providers.length === 0) {
      throw new Error('No fundamentals providers available');
    }

    let lastError: Error | undefined;

    for (const provider of providers) {
      const entry = this.fundamentalsProviders.get(provider.name)!;

      try {
        const result = await this.fetchWithRetry(
          () => provider.fetchData({ type: 'fundamentals-current', ticker }),
          entry.config
        );

        entry.successCount++;

        const fundamentals = result as IStockFundamentals;
        const ttl = (entry.config as IFundamentalsProviderConfig).cacheTTL || this.config.cache.fundamentalsTTL;
        this.addToCache(this.fundamentalsCache, cacheKey, fundamentals, ttl);

        console.log(`Successfully fetched fundamentals for ${ticker} from ${provider.name}`);
        return fundamentals;
      } catch (error) {
        entry.errorCount++;
        entry.lastError = error as Error;
        entry.lastErrorTime = new Date();
        lastError = error as Error;

        console.warn(`Provider ${provider.name} failed for ${ticker} fundamentals: ${error.message}`);
      }
    }

    throw new Error(
      `Failed to fetch fundamentals for ${ticker} from all providers. Last error: ${lastError?.message}`
    );
  }

  /**
   * Get fundamentals for multiple tickers
   */
  public async getBatchFundamentals(tickers: string[]): Promise<IStockFundamentals[]> {
    const cacheKey = `fundamentals-batch:${tickers.sort().join(',')}`;
    const cached = this.getFromCache(this.fundamentalsCache, cacheKey);

    if (cached) {
      console.log(`Cache hit for batch fundamentals: ${tickers.length} tickers`);
      return cached as IStockFundamentals[];
    }

    const providers = this.getEnabledFundamentalsProviders();
    if (providers.length === 0) {
      throw new Error('No fundamentals providers available');
    }

    let lastError: Error | undefined;

    for (const provider of providers) {
      const entry = this.fundamentalsProviders.get(provider.name)!;

      try {
        const result = await this.fetchWithRetry(
          () => provider.fetchData({ type: 'fundamentals-batch', tickers }),
          entry.config
        );

        entry.successCount++;

        const fundamentals = result as IStockFundamentals[];
        const ttl = (entry.config as IFundamentalsProviderConfig).cacheTTL || this.config.cache.fundamentalsTTL;
        this.addToCache(this.fundamentalsCache, cacheKey, fundamentals, ttl);

        console.log(`Successfully fetched ${fundamentals.length} fundamentals from ${provider.name}`);
        return fundamentals;
      } catch (error) {
        entry.errorCount++;
        entry.lastError = error as Error;
        entry.lastErrorTime = new Date();
        lastError = error as Error;

        console.warn(`Provider ${provider.name} failed for batch fundamentals: ${error.message}`);
      }
    }

    throw new Error(
      `Failed to fetch fundamentals for ${tickers.length} tickers from all providers. Last error: ${lastError?.message}`
    );
  }

  /**
   * ✨ Get complete stock data (price + fundamentals) with automatic enrichment
   */
  public async getStockData(request: string | ICompleteStockDataRequest): Promise<IStockData> {
    const normalizedRequest = typeof request === 'string'
      ? { ticker: request, includeFundamentals: true, enrichFundamentals: true }
      : { includeFundamentals: true, enrichFundamentals: true, ...request };

    const price = await this.getPrice(normalizedRequest.ticker);

    let fundamentals: IStockFundamentals | undefined;

    if (normalizedRequest.includeFundamentals) {
      try {
        fundamentals = await this.getFundamentals(normalizedRequest.ticker);

        // Enrich fundamentals with price calculations
        if (normalizedRequest.enrichFundamentals && fundamentals) {
          fundamentals = this.enrichWithPrice(fundamentals, price.price);
        }
      } catch (error) {
        console.warn(`Failed to fetch fundamentals for ${normalizedRequest.ticker}: ${error.message}`);
        // Continue without fundamentals
      }
    }

    return {
      ticker: normalizedRequest.ticker,
      price,
      fundamentals,
      fetchedAt: new Date()
    };
  }

  /**
   * ✨ Get complete stock data for multiple tickers with automatic enrichment
   */
  public async getBatchStockData(request: string[] | ICompleteStockDataBatchRequest): Promise<IStockData[]> {
    const normalizedRequest = Array.isArray(request)
      ? { tickers: request, includeFundamentals: true, enrichFundamentals: true }
      : { includeFundamentals: true, enrichFundamentals: true, ...request };

    const prices = await this.getPrices(normalizedRequest.tickers);
    const priceMap = new Map(prices.map(p => [p.ticker, p]));

    let fundamentalsMap = new Map<string, IStockFundamentals>();

    if (normalizedRequest.includeFundamentals) {
      try {
        const fundamentals = await this.getBatchFundamentals(normalizedRequest.tickers);

        // Enrich with prices if requested
        if (normalizedRequest.enrichFundamentals) {
          for (const fund of fundamentals) {
            const price = priceMap.get(fund.ticker);
            if (price) {
              fundamentalsMap.set(fund.ticker, this.enrichWithPrice(fund, price.price));
            } else {
              fundamentalsMap.set(fund.ticker, fund);
            }
          }
        } else {
          fundamentalsMap = new Map(fundamentals.map(f => [f.ticker, f]));
        }
      } catch (error) {
        console.warn(`Failed to fetch batch fundamentals: ${error.message}`);
        // Continue without fundamentals
      }
    }

    return normalizedRequest.tickers.map(ticker => ({
      ticker,
      price: priceMap.get(ticker)!,
      fundamentals: fundamentalsMap.get(ticker),
      fetchedAt: new Date()
    }));
  }

  // ========== Helper Methods ==========

  /**
   * Enrich fundamentals with calculated metrics using current price
   */
  private enrichWithPrice(fundamentals: IStockFundamentals, price: number): IStockFundamentals {
    const enriched = { ...fundamentals };

    // Calculate market cap: price × shares outstanding
    if (fundamentals.sharesOutstanding) {
      enriched.marketCap = price * fundamentals.sharesOutstanding;
    }

    // Calculate P/E ratio: price / EPS
    if (fundamentals.earningsPerShareDiluted && fundamentals.earningsPerShareDiluted > 0) {
      enriched.priceToEarnings = price / fundamentals.earningsPerShareDiluted;
    }

    // Calculate price-to-book: market cap / stockholders equity
    if (enriched.marketCap && fundamentals.stockholdersEquity && fundamentals.stockholdersEquity > 0) {
      enriched.priceToBook = enriched.marketCap / fundamentals.stockholdersEquity;
    }

    return enriched;
  }

  /**
   * Fetch with retry logic
   */
  private async fetchWithRetry<T>(
    fetchFn: () => Promise<T>,
    config: IProviderConfig | IFundamentalsProviderConfig
  ): Promise<T> {
    const maxAttempts = config.retryAttempts || 1;
    let lastError: Error | undefined;

    for (let attempt = 1; attempt <= maxAttempts; attempt++) {
      try {
        return await fetchFn();
      } catch (error) {
        lastError = error as Error;

        if (attempt < maxAttempts) {
          const delay = (config.retryDelay || 1000) * attempt;
          console.log(`Retry attempt ${attempt} after ${delay}ms`);
          await plugins.smartdelay.delayFor(delay);
        }
      }
    }

    throw lastError || new Error('Unknown error during fetch');
  }

  /**
   * Get from cache if not expired
   */
  private getFromCache<T>(cache: Map<string, ICacheEntry<T>>, key: string): T | null {
    const entry = cache.get(key);

    if (!entry) {
      return null;
    }

    // Check if cache entry has expired
    const age = Date.now() - entry.timestamp.getTime();
    if (entry.ttl !== Infinity && age > entry.ttl) {
      cache.delete(key);
      return null;
    }

    return entry.data;
  }

  /**
   * Add to cache with TTL
   */
  private addToCache<T>(cache: Map<string, ICacheEntry<T>>, key: string, data: T, ttl: number): void {
    // Enforce max entries limit
    if (cache.size >= this.config.cache.maxEntries) {
      // Remove oldest entry
      const oldestKey = cache.keys().next().value;
      if (oldestKey) {
        cache.delete(oldestKey);
      }
    }

    cache.set(key, {
      data,
      timestamp: new Date(),
      ttl
    });
  }

  // ========== Health & Statistics ==========

  /**
   * Check health of all providers (both price and fundamentals)
   */
  public async checkProvidersHealth(): Promise<Map<string, boolean>> {
    const health = new Map<string, boolean>();

    // Check price providers
    for (const [name, entry] of this.priceProviders) {
      if (!entry.config.enabled) {
        health.set(`${name} (price)`, false);
        continue;
      }

      try {
        const isAvailable = await entry.provider.isAvailable();
        health.set(`${name} (price)`, isAvailable);
      } catch (error) {
        health.set(`${name} (price)`, false);
        console.error(`Health check failed for ${name}:`, error);
      }
    }

    // Check fundamentals providers
    for (const [name, entry] of this.fundamentalsProviders) {
      if (!entry.config.enabled) {
        health.set(`${name} (fundamentals)`, false);
        continue;
      }

      try {
        const isAvailable = await entry.provider.isAvailable();
        health.set(`${name} (fundamentals)`, isAvailable);
      } catch (error) {
        health.set(`${name} (fundamentals)`, false);
        console.error(`Health check failed for ${name}:`, error);
      }
    }

    return health;
  }

  /**
   * Get statistics for all providers
   */
  public getProviderStats(): Map<
    string,
    {
      type: 'price' | 'fundamentals';
      successCount: number;
      errorCount: number;
      lastError?: string;
      lastErrorTime?: Date;
    }
  > {
    const stats = new Map();

    // Price provider stats
    for (const [name, entry] of this.priceProviders) {
      stats.set(name, {
        type: 'price',
        successCount: entry.successCount,
        errorCount: entry.errorCount,
        lastError: entry.lastError?.message,
        lastErrorTime: entry.lastErrorTime
      });
    }

    // Fundamentals provider stats
    for (const [name, entry] of this.fundamentalsProviders) {
      stats.set(name, {
        type: 'fundamentals',
        successCount: entry.successCount,
        errorCount: entry.errorCount,
        lastError: entry.lastError?.message,
        lastErrorTime: entry.lastErrorTime
      });
    }

    return stats;
  }

  /**
   * Clear all caches
   */
  public clearCache(): void {
    this.priceCache.clear();
    this.fundamentalsCache.clear();
    console.log('All caches cleared');
  }

  /**
   * Get cache statistics
   */
  public getCacheStats(): {
    priceCache: { size: number; ttl: number };
    fundamentalsCache: { size: number; ttl: number };
    maxEntries: number;
  } {
    return {
      priceCache: {
        size: this.priceCache.size,
        ttl: this.config.cache.priceTTL
      },
      fundamentalsCache: {
        size: this.fundamentalsCache.size,
        ttl: this.config.cache.fundamentalsTTL
      },
      maxEntries: this.config.cache.maxEntries
    };
  }
}