text: /*
   * Copyright (C) 2010 Apple Inc. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
   * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
   * THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifndef GenericCallback_h
  #define GenericCallback_h
  
  #include "ShareableBitmap.h"
  #include "WKAPICast.h"
  #include "WebError.h"
  #include <wtf/HashMap.h>
  #include <wtf/PassRefPtr.h>
  #include <wtf/RefCounted.h>
  
  namespace WebKit {
  
  class CallbackBase : public RefCounted<CallbackBase> {
  public:
      virtual ~CallbackBase()
      {
      }
  
      uint64_t callbackID() const { return m_callbackID; }
  
  protected:
      explicit CallbackBase(void* context)
          : m_context(context)
          , m_callbackID(generateCallbackID())
      {
      }
  
      void* context() const { return m_context; }
  
  private:
      static uint64_t generateCallbackID()
      {
          static uint64_t uniqueCallbackID = 1;
          return uniqueCallbackID++;
      }
  
      void* m_context;
      uint64_t m_callbackID;
  };
  
  class VoidCallback : public CallbackBase {
  public:
      typedef void (*CallbackFunction)(WKErrorRef, void*);
  
      static PassRefPtr<VoidCallback> create(void* context, CallbackFunction callback)
      {
          return adoptRef(new VoidCallback(context, callback));
      }
  
      virtual ~VoidCallback()
      {
          ASSERT(!m_callback);
      }
  
      void performCallback()
      {
          ASSERT(m_callback);
  
          m_callback(0, context());
  
          m_callback = 0;
      }
      
      void invalidate()
      {
          ASSERT(m_callback);
  
          RefPtr<WebError> error = WebError::create();
          m_callback(toAPI(error.get()), context());
          
          m_callback = 0;
      }
  
  private:
      VoidCallback(void* context, CallbackFunction callback)
          : CallbackBase(context)
          , m_callback(callback)
      {
      }
  
      CallbackFunction m_callback;
  };
  
  template<typename APIReturnValueType, typename InternalReturnValueType = typename APITypeInfo<APIReturnValueType>::ImplType>
  class GenericCallback : public CallbackBase {
  public:
      typedef void (*CallbackFunction)(APIReturnValueType, WKErrorRef, void*);
  
      static PassRefPtr<GenericCallback> create(void* context, CallbackFunction callback)
      {
          return adoptRef(new GenericCallback(context, callback));
      }
  
      virtual ~GenericCallback()
      {
          ASSERT(!m_callback);
      }
  
      void performCallbackWithReturnValue(InternalReturnValueType returnValue)
      {
          ASSERT(m_callback);
  
          m_callback(toAPI(returnValue), 0, context());
  
          m_callback = 0;
      }
      
      void invalidate()
      {
          ASSERT(m_callback);
  
          RefPtr<WebError> error = WebError::create();
          m_callback(0, toAPI(error.get()), context());
          
          m_callback = 0;
      }
  
  private:
      GenericCallback(void* context, CallbackFunction callback)
          : CallbackBase(context)
          , m_callback(callback)
      {
      }
  
      CallbackFunction m_callback;
  };
  
  // FIXME: Make a version of CallbackBase with two arguments, and define ComputedPagesCallback as a specialization.
  class ComputedPagesCallback : public CallbackBase {
  public:
      typedef void (*CallbackFunction)(const Vector<WebCore::IntRect>&, double, WKErrorRef, void*);
  
      static PassRefPtr<ComputedPagesCallback> create(void* context, CallbackFunction callback)
      {
          return adoptRef(new ComputedPagesCallback(context, callback));
      }
  
      virtual ~ComputedPagesCallback()
      {
          ASSERT(!m_callback);
      }
  
      void performCallbackWithReturnValue(const Vector<WebCore::IntRect>& returnValue1, double returnValue2)
      {
          ASSERT(m_callback);
  
          m_callback(returnValue1, returnValue2, 0, context());
  
          m_callback = 0;
      }
      
      void invalidate()
      {
          ASSERT(m_callback);
  
          RefPtr<WebError> error = WebError::create();
          m_callback(Vector<WebCore::IntRect>(), 0, toAPI(error.get()), context());
          
          m_callback = 0;
      }
  
  private:
  
      ComputedPagesCallback(void* context, CallbackFunction callback)
          : CallbackBase(context)
          , m_callback(callback)
      {
      }
  
      CallbackFunction m_callback;
  };
  
  class ImageCallback : public CallbackBase {
  public:
      typedef void (*CallbackFunction)(const ShareableBitmap::Handle&, WKErrorRef, void*);
  
      static PassRefPtr<ImageCallback> create(void* context, CallbackFunction callback)
      {
          return adoptRef(new ImageCallback(context, callback));
      }
  
      virtual ~ImageCallback()
      {
          ASSERT(!m_callback);
      }
  
      void performCallbackWithReturnValue(const ShareableBitmap::Handle& returnValue1)
      {
          ASSERT(m_callback);
  
          m_callback(returnValue1, 0, context());
  
          m_callback = 0;
      }
  
      void invalidate()
      {
          ASSERT(m_callback);
  
          RefPtr<WebError> error = WebError::create();
          ShareableBitmap::Handle handle;
          m_callback(handle, toAPI(error.get()), context());
  
          m_callback = 0;
      }
  
  private:
  
      ImageCallback(void* context, CallbackFunction callback)
          : CallbackBase(context)
          , m_callback(callback)
      {
      }
      
      CallbackFunction m_callback;
  };
  
  template<typename T>
  void invalidateCallbackMap(HashMap<uint64_t, T>& map)
  {
      Vector<T> callbacksVector;
      copyValuesToVector(map, callbacksVector);
      for (size_t i = 0, size = callbacksVector.size(); i < size; ++i)
          callbacksVector[i]->invalidate();
      map.clear();
  }
  
  } // namespace WebKit
  
  #endif // GenericCallback_h
  