package com.foxinmy.weixin4j.http.factory;
   
   import java.security.KeyManagementException;
   import java.security.NoSuchAlgorithmException;
   import java.security.cert.CertificateException;
   import java.security.cert.X509Certificate;
   
   import javax.net.ssl.HostnameVerifier;
   import javax.net.ssl.SSLContext;
  import javax.net.ssl.SSLSession;
  import javax.net.ssl.X509TrustManager;
  
  import com.foxinmy.weixin4j.http.HttpClient;
  import com.foxinmy.weixin4j.http.HttpParams;
  import com.foxinmy.weixin4j.http.support.apache3.HttpComponent3Factory;
  import com.foxinmy.weixin4j.http.support.apache4.HttpComponent4Factory;
  import com.foxinmy.weixin4j.http.support.netty.Netty4HttpClientFactory;
  import com.foxinmy.weixin4j.http.support.okhttp.OkHttpClientFactory;
  
  /**
   * HttpClient工厂生产类:参考netty的InternalLoggerFactory
   * 
   * @className HttpClientFactory
   * @author jinyu(foxinmy@gmail.com)
   * @date 2015年8月12日
   * @since JDK 1.6
   * @see
   */
  public abstract class HttpClientFactory {
  
  	/**
  	 * 默认的HttpClient
  	 */
  	private static volatile HttpClientFactory defaultFactory = newDefaultFactory();
  	private static volatile HttpParams defaultParams;
  
  	/**
  	 * NettyHttpClient -> ApacheHttpClient(HttpComponent3&4) ->
  	 * OkHttpClient(2&3) -> SimpleHttpClient(HttpURLConnection)
  	 * 
  	 * @return
  	 */
  	private static HttpClientFactory newDefaultFactory() {
  		HttpClientFactory f;
  		try {
  			f = new Netty4HttpClientFactory();
  		} catch (Throwable e1) {
  			try {
  				f = new HttpComponent4Factory();
  			} catch (Throwable e2) {
  				try {
  					f = new HttpComponent3Factory();
  				} catch (Throwable e3) {
  					try {
  						f = new OkHttpClientFactory();
  					} catch (Throwable e4) {
  						f = new SimpleHttpClientFactory();
  					}
  				}
  			}
  		}
  		return f;
  	}
  
  	/**
  	 * 获取默认的HttpClient
  	 * 
  	 * @return
  	 */
  	public static HttpClientFactory getDefaultFactory() {
  		return defaultFactory;
  	}
  
  	/**
  	 * 显式设置默认的HttpClient
  	 * 
  	 * @param defaultFactory
  	 */
  	public static void setDefaultFactory(HttpClientFactory defaultFactory) {
  		if (defaultFactory == null) {
  			throw new IllegalArgumentException(
  					"'defaultFactory' must not be empty");
  		}
  		HttpClientFactory.defaultFactory = defaultFactory;
  	}
  
  	/**
  	 * 获取默认的HttpParams
  	 * 
  	 * @return
  	 */
  	public static HttpParams getDefaultParams() {
  		return defaultParams;
  	}
  
  	/**
  	 * Resolve the Http Parameter
  	 * 
  	 * @param params
 	 *            请求参数
 	 */
 	public static void setDefaultParams(HttpParams params) {
 		if (params == null) {
 			throw new IllegalArgumentException("'params' must not be empty");
 		}
 		HttpClientFactory.defaultParams = params;
 	}
 
 	/**
 	 * 获取HttpClient实例
 	 * 
 	 * @return
 	 */
 	public static HttpClient getInstance() {
 		return getInstance(HttpClientFactory.defaultParams);
 	}
 
 	/**
 	 * 获取HttpClient实例
 	 * 
 	 * @param params
 	 *            Http参数
 	 * 
 	 * @return HttpClinet实例
 	 */
 	public static HttpClient getInstance(HttpParams params) {
 		HttpClientFactory clientFactory = getDefaultFactory();
 		return clientFactory.newInstance(params);
 	}
 
 	/**
 	 * 获取HttpClient实例
 	 * 
 	 * @param params
 	 *            http参数 可为空
 	 * @return
 	 */
 	public abstract HttpClient newInstance(HttpParams params);
 
 	public static SSLContext allowSSLContext() {
 		try {
 			SSLContext sslContext = SSLContext.getInstance("TLS");
 			sslContext.init(null,
 					new X509TrustManager[] { AllowX509TrustManager.GLOBAL },
 					new java.security.SecureRandom());
 			return sslContext;
 		} catch (NoSuchAlgorithmException e) {
 			throw new RuntimeException(
 					"Create SSLContext NoSuchAlgorithmException:", e);
 		} catch (KeyManagementException e) {
 			throw new RuntimeException(
 					"Create SSLContext KeyManagementException:", e);
 		}
 	}
 
 	public static class AllowX509TrustManager implements X509TrustManager {
 		public static final X509TrustManager GLOBAL = new AllowX509TrustManager();
 
 		private AllowX509TrustManager() {
 		}
 
 		@Override
 		public X509Certificate[] getAcceptedIssuers() {
 			return new X509Certificate[0];
 		}
 
 		@Override
 		public void checkServerTrusted(
 				X509Certificate[] paramArrayOfX509Certificate,
 				String paramString) throws CertificateException {
 		}
 
 		@Override
 		public void checkClientTrusted(
 				X509Certificate[] paramArrayOfX509Certificate,
 				String paramString) throws CertificateException {
 		}
 	}
 
 	public static class AllowHostnameVerifier implements HostnameVerifier {
 		public static final HostnameVerifier GLOBAL = new AllowHostnameVerifier();
 
 		private AllowHostnameVerifier() {
 		}
 
 		@Override
 		public boolean verify(String hostname, SSLSession session) {
 			return true;
 		}
 	}
 }