content: /*
   * Original work Copyright (c) 2015, Alibaba Mobile Infrastructure (Android) Team
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.taobao.patch;
  
  
  import android.content.Context;
  
  import java.io.File;
  import java.util.Enumeration;
  import java.util.HashMap;
  
  import dalvik.system.DexClassLoader;
  import dalvik.system.DexFile;
  
  /**
  * 
  * <p>PatchMain is used to load a patch apk file.</p>
  * 
  * <p>Note:The patch apk must not include the classes which are already in loader apk, so the patch.jar and dexposed.jar
  * should be included in hotpatchpatch project, but not output to patch apk.</p>
  * 
  * <p>Before using this, one necessary condition, the libdexposed.so, libdexposed2.3.so and dexposedbridge.jar must
  * be included in loader project.</p>
  * 
  * <p>The patch apk file should just normal apk which include some patch classes to hook
  * methods you want to modify. These patch classes will be invoked auto if load(...) of this called.</p>  
  *
  * <p>About patch class, which must implement IPatch interface and override handlePatch.</p>
  * 
  * The sample:
  * <pre class="prettyprint">
  *   public class HotPatchTest implements IPatch {
  *      //@Override
  *	   public void handlePatch(final PatchParam arg0) throws Throwable {
  *	   }
  *	}
  * </pre>
  *  
  *  <p>The PatchParam includes context and an object HashMap which include objects may be used by patch class. 
  *  And that object HashMap is equal the arg one sent in load() method. </p>
  *  
  *  <p>How to implement handlePatch method?</p>
  *  
  *  <p>First, it needs to find class which will be patched. 
  *  PatchParams' member context has the getClassLoader to load class that you want to patch.</p>
  *  
  *  <p>Then, the XposedBridge.findAndHookMethod should be used here. The first argument is the patching class,
  *  and the second is the patching method name, and the following arguments are the patching method' arguments type class.
  *  The last argument is the instance of XC_MethodHook or XC_MethodReplacement, the following are description for these two.</p>
  *  
  *  <p>The XC_MethodHook has two methods beforeHookedMethod and afterHookedMethod, and these easy to understand that they are called
  *  before/after the invocation of the hooked method. </p>
  *  
  *  <p>The XC_MethodReplacement has method replaceHookedMethod to replace the whole original method.</p>
  *  
  *  <P>The MethodHookParam is the only argument used in above three methods, which include some useful contents.
  *  MethodHookParam.thisObject is the instance of this class.
  *  In MethodHookParam.args, it offers all argument values of this method.
  *  And MethodHookParam.setResult can modify the result of the method call. In a "before-method-call"
  *  hook, prevents the call to the original method. But it still need to "return" from the hook handler if required.</p>
  *  
  *  <P>Finally, this load() method will return the PatchResult which show the result or error detail. </p>
  *  
  *  @version 1.0
  */
  
  public class PatchMain {
  	
  	private static final ReadWriteSet<PatchCallback> loadedPatchCallbacks = new ReadWriteSet<PatchCallback>();	
  
  	 /**
       * Load a runnable patch apk.
       *
       * @param context the application or activity context.
       * @param apkPath the path of patch apk file.
       * @param contentMap the object maps that will be used by patch classes.  
       * @return PatchResult include if success or error detail.
       */
  	public static PatchResult load(Context context, String apkPath, HashMap<String, Object> contentMap) {
  		
  		if (!new File(apkPath).exists()) {
  			return new PatchResult(false, PatchResult.FILE_NOT_FOUND, "FILE not found on " + apkPath);
  		}
  
  	    PatchResult result = loadAllCallbacks(context, apkPath,context.getClassLoader());
  		if (!result.isSuccess()) {
  			return result;
  		}
  
  		if (loadedPatchCallbacks.getSize() == 0) {
  			return new PatchResult(false, PatchResult.NO_PATCH_CLASS_HANDLE, "No patch class to be handle");
  		}
  		
  		PatchParam lpparam = new PatchParam(loadedPatchCallbacks);		
  		lpparam.context = context;
  		lpparam.contentMap = contentMap;
  		
  		return PatchCallback.callAll(lpparam);
  	}
  
  	private static PatchResult loadAllCallbacks(Context context, String apkPath, ClassLoader cl) {
  		try {
  //			String dexPath = new File(context.getFilesDir(), apkPath.).getAbsolutePath();
  			File dexoptFile = new File(apkPath + "odex");
  			if (dexoptFile.exists()) {
  				dexoptFile.delete();
  			}
  			ClassLoader mcl = null;			
  			try {
  				mcl = new DexClassLoader (apkPath,context.getFilesDir().getAbsolutePath(),null, cl);
  			}catch(Throwable e){
  				return new PatchResult(false, PatchResult.FOUND_PATCH_CLASS_EXCEPTION, "Find patch class exception ", e);
  			}
  			DexFile dexFile = DexFile.loadDex(apkPath, context.getFilesDir().getAbsolutePath() + File.separator + "patch.odex", 0);
  			Enumeration<String> entrys = dexFile.entries();
  			// clean old callback
  			synchronized (loadedPatchCallbacks) {
  				loadedPatchCallbacks.clear();
  			}
  			while (entrys.hasMoreElements()) {
  				String entry = entrys.nextElement();				
  				Class<?> entryClass = null;
  				try {
  					entryClass = mcl.loadClass(entry);
  				} catch (ClassNotFoundException e) {
  					e.printStackTrace();
  					break;
  				}
  				if (isImplementInterface(entryClass, IPatch.class)) {
  					Object moduleInstance = entryClass.newInstance();
  					hookLoadPatch(new PatchCallback((IPatch) moduleInstance));
  				}
  			}
  
  		} catch (Exception e) {
  			return new PatchResult(false, PatchResult.FOUND_PATCH_CLASS_EXCEPTION, "Find patch class exception ", e);
  		}
  		return new PatchResult(true, PatchResult.NO_ERROR, "");
  	}
  	
  	private static boolean isImplementInterface(Class<?> entry, Class<?> interClass) {
  		Class<?>[] interfaces = entry.getInterfaces();
  		if (interfaces == null) {
  			return false;
  		}
  		for (int i = 0; i < interfaces.length; i++) {
  			if (interfaces[i].equals(interClass)) {
  				return true;
  			}
  		}
  		return false;		
  	}
  	
  	/**
  	 * Get notified when a patch is loaded. This is especially useful to hook some patch-specific methods.
  	 */
  	private static void hookLoadPatch(PatchCallback callback) {
  		synchronized (loadedPatchCallbacks) {
  			loadedPatchCallbacks.add(callback);
  		}
  	}
  }
  