// Client initiates request
const priceHistory = await sdk.priceHistoryApi.getPriceHistory('DOT', '1W');

// PriceHistoryApi processes the request
export class PriceHistoryApi extends BaseApi {
  async getPriceHistory(token: string, type: Timeframe) {
    // Parameter validation
    if (!token || !type) {
      throw new ValidationError('Token and type are required');
    }
    
    // Route to BaseApi
    return this.get<HistoryTokenPriceJSON>({
      params: { token, type },
      path: 'price-history'
    });
  }
}

// BaseApi handles the HTTP communication
export class BaseApi {
  async get<T>(options: GetOptions): Promise<T> {
    return this.request<T>({
      method: 'GET',
      ...options
    });
  }
  
  async request<T>(options: RequestOptions): Promise<T> {
    // Build request URL with parameters
    let requestUrl = `${this.config.baseUrl}/${options.path}`;
    
    // Add query parameters
    if (options.params) {
      const queryParams = new URLSearchParams(options.params).toString();
      requestUrl += `?${queryParams}`;
    }
    
    // Execute HTTP request with configuration
    const response = await fetch(requestUrl, {
      method: options.method ?? 'GET',
      headers: {
        'Content-Type': 'application/json',
        ...this.config.headers,
        ...options.headers
      },
      body: options.data ? JSON.stringify(options.data) : undefined
    });
    
    // Process response
    return this.processResponse<T>(response);
  }
}

// Client updates configuration
sdk.updateConfig({
  platform: 'mobile',
  baseUrl: 'https://staging-api.subwallet.app'
});

// SDK processes the update
updateConfig(newConfig: Partial<SDKOption>) {
  // Merge with existing configuration
  this.config = {
    ...this.config,
    ...newConfig
  };
  
  // Regenerate API configuration
  const apiConfig = this.apiConfig;
  
  // Update all services
  this.serviceList.forEach((service) => {
    service.updateConfig(apiConfig);
  });
}

// Dynamic header generation based on configuration
get headers() {
  return {
    'SW-SDK-ChainList-Version': this.config.chainListVersion,
    'SW-SDK-Platform': this.config.platform,
    'SW-SDK-Version': this.config.sdkVersion
  };
}

get apiConfig(): ApiConfig {
  return {
    baseUrl: this.config.baseUrl,
    headers: this.headers
  };
}

// Error processing in BaseApi
async request<T>(options: RequestOptions): Promise<T> {
  try {
    const response = await fetch(requestUrl, fetchOptions);
    
    // Handle HTTP errors
    if (!response.ok) {
      const errorText = await response.text();
      throw new SdkError(errorText, { 
        code: response.status, 
        type: ErrorType.REQUEST_ERROR 
      });
    }
    
    const apiResponse = await response.json() as SWApiResponse<T>;
    
    // Handle API errors
    if (apiResponse.error) {
      throw new SdkError(apiResponse.error.message || 'Unknown error', { 
        code: apiResponse.error.code 
      });
    }
    
    return apiResponse.data || apiResponse.result;
    
  } catch (error) {
    // Transform and re-throw with context
    throw new Error(`Failed to fetch data: ${(error as Error).message}`);
  }
}

// Example: Portfolio balance with price data
async getPortfolioValue(addresses: string[], chains: string[]) {
  // 1. Get balances from BalanceDetectionApi
  const balances = await sdk.balanceDetectionApi.getBalances({
    addresses,
    chains
  });
  
  // 2. Get current prices for detected tokens
  const pricePromises = balances.tokens.map(token => 
    sdk.priceHistoryApi.getCurrentPrice(token.symbol)
  );
  
  const prices = await Promise.all(pricePromises);
  
  // 3. Calculate total portfolio value
  return balances.tokens.map((token, index) => ({
    ...token,
    price: prices[index],
    value: token.balance * prices[index].current
  }));
}

// Raw API response
interface RawPriceResponse {
  history: Array<{
    time: number;
    value: number;
  }>;
}

// Transformed client response
interface PriceChartPoint {
  time: number;
  value: number;
  formatted?: {
    time: string;
    value: string;
  };
}

// Transformation logic
private transformPriceHistory(raw: RawPriceResponse): HistoryTokenPriceJSON {
  return {
    history: raw.history.map(point => ({
      time: point.time,
      value: point.value,
      formatted: {
        time: new Date(point.time).toISOString(),
        value: `$${point.value.toFixed(2)}`
      }
    }))
  };
}

// Raw balance response normalization
interface RawBalanceResponse {
  balances: Array<{
    address: string;
    chain: string;
    tokens: Array<{
      symbol: string;
      balance: string;
      decimals: number;
    }>;
  }>;
}

// Client-friendly format
interface NormalizedBalance {
  address: string;
  chain: string;
  tokens: Array<{
    symbol: string;
    balance: bigint;
    displayBalance: string;
    decimals: number;
  }>;
}

// HTTP client with connection reuse
class OptimizedHttpClient {
  private connectionPool: Map<string, Connection> = new Map();
  
  async request(url: string, options: RequestOptions) {
    const connection = this.getOrCreateConnection(url);
    return connection.request(options);
  }
  
  private getOrCreateConnection(url: string): Connection {
    const baseUrl = new URL(url).origin;
    
    if (!this.connectionPool.has(baseUrl)) {
      this.connectionPool.set(baseUrl, new Connection(baseUrl));
    }
    
    return this.connectionPool.get(baseUrl)!;
  }
}

// Batch multiple requests to the same endpoint
class BatchingLayer {
  private pendingRequests: Map<string, Promise<any>> = new Map();
  
  async batchRequest<T>(key: string, requestFn: () => Promise<T>): Promise<T> {
    if (this.pendingRequests.has(key)) {
      return this.pendingRequests.get(key) as Promise<T>;
    }
    
    const promise = requestFn();
    this.pendingRequests.set(key, promise);
    
    // Clean up after request completes
    promise.finally(() => {
      this.pendingRequests.delete(key);
    });
    
    return promise;
  }
}

// Service-level caching implementation
class CachingService {
  private cache: Map<string, CacheEntry> = new Map();
  
  async cachedRequest<T>(
    key: string, 
    requestFn: () => Promise<T>,
    ttl: number = 60000
  ): Promise<T> {
    const cached = this.cache.get(key);
    
    if (cached && Date.now() - cached.timestamp < ttl) {
      return cached.data as T;
    }
    
    const fresh = await requestFn();
    this.cache.set(key, {
      data: fresh,
      timestamp: Date.now()
    });
    
    return fresh;
  }
}