// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.  All rights reserved.
// http://code.google.com/p/protobuf/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * 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.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT
// OWNER OR 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
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// Author: kenton@google.com (Kenton Varda)
//  Based on original Protocol Buffers design by
//  Sanjay Ghemawat, Jeff Dean, and others.
//
// Contains methods defined in extension_set.h which cannot be part of the
// lite library because they use descriptors or reflection.

#include <google/protobuf/extension_set.h>
#include <google/protobuf/descriptor.h>
#include <google/protobuf/message.h>
#include <google/protobuf/repeated_field.h>
#include <google/protobuf/wire_format.h>

namespace google {
namespace protobuf {
namespace internal {

void ExtensionSet::AppendToList(const Descriptor* containing_type,
                                const DescriptorPool* pool,
                                vector<const FieldDescriptor*>* output) const {
  for (map<int, Extension>::const_iterator iter = extensions_.begin();
       iter != extensions_.end(); ++iter) {
    bool has = false;
    if (iter->second.is_repeated) {
      has = iter->second.GetSize() > 0;
    } else {
      has = !iter->second.is_cleared;
    }

    if (has) {
      output->push_back(
          pool->FindExtensionByNumber(containing_type, iter->first));
    }
  }
}

inline FieldDescriptor::CppType cpp_type(FieldType type) {
  return FieldDescriptor::TypeToCppType(
      static_cast<FieldDescriptor::Type>(type));
}

#define GOOGLE_DCHECK_TYPE(EXTENSION, LABEL, CPPTYPE)                            \
  GOOGLE_DCHECK_EQ((EXTENSION).is_repeated ? FieldDescriptor::LABEL_REPEATED     \
                                  : FieldDescriptor::LABEL_OPTIONAL,      \
            FieldDescriptor::LABEL_##LABEL);                              \
  GOOGLE_DCHECK_EQ(cpp_type((EXTENSION).type), FieldDescriptor::CPPTYPE_##CPPTYPE)

const MessageLite& ExtensionSet::GetMessage(int number,
                                            const Descriptor* message_type,
                                            MessageFactory* factory) const {
  map<int, Extension>::const_iterator iter = extensions_.find(number);
  if (iter == extensions_.end() || iter->second.is_cleared) {
    // Not present.  Return the default value.
    return *factory->GetPrototype(message_type);
  } else {
    GOOGLE_DCHECK_TYPE(iter->second, OPTIONAL, MESSAGE);
    return *iter->second.message_value;
  }
}

MessageLite* ExtensionSet::MutableMessage(int number, FieldType type,
                                          const Descriptor* message_type,
                                          MessageFactory* factory) {
  Extension* extension;
  if (MaybeNewExtension(number, &extension)) {
    extension->type = type;
    GOOGLE_DCHECK_EQ(cpp_type(extension->type), FieldDescriptor::CPPTYPE_MESSAGE);
    extension->is_repeated = false;
    extension->is_packed = false;
    const MessageLite* prototype = factory->GetPrototype(message_type);
    GOOGLE_CHECK(prototype != NULL);
    extension->message_value = prototype->New();
  } else {
    GOOGLE_DCHECK_TYPE(*extension, OPTIONAL, MESSAGE);
  }
  extension->is_cleared = false;
  return extension->message_value;
}

MessageLite* ExtensionSet::AddMessage(int number, FieldType type,
                                      const Descriptor* message_type,
                                      MessageFactory* factory) {
  Extension* extension;
  if (MaybeNewExtension(number, &extension)) {
    extension->type = type;
    GOOGLE_DCHECK_EQ(cpp_type(extension->type), FieldDescriptor::CPPTYPE_MESSAGE);
    extension->is_repeated = true;
    extension->repeated_message_value =
      new RepeatedPtrField<MessageLite>();
  } else {
    GOOGLE_DCHECK_TYPE(*extension, REPEATED, MESSAGE);
  }

  // RepeatedPtrField<Message> does not know how to Add() since it cannot
  // allocate an abstract object, so we have to be tricky.
  MessageLite* result = extension->repeated_message_value
      ->AddFromCleared<internal::GenericTypeHandler<MessageLite> >();
  if (result == NULL) {
    const MessageLite* prototype;
    if (extension->repeated_message_value->size() == 0) {
      prototype = factory->GetPrototype(message_type);
      GOOGLE_CHECK(prototype != NULL);
    } else {
      prototype = &extension->repeated_message_value->Get(0);
    }
    result = prototype->New();
    extension->repeated_message_value->AddAllocated(result);
  }
  return result;
}

bool ExtensionSet::ParseField(uint32 tag, io::CodedInputStream* input,
                              const MessageLite* containing_type,
                              UnknownFieldSet* unknown_fields) {
  UnknownFieldSetFieldSkipper skipper(unknown_fields);
  return ParseField(tag, input, containing_type, &skipper);
}

bool ExtensionSet::ParseMessageSet(io::CodedInputStream* input,
                                   const MessageLite* containing_type,
                                   UnknownFieldSet* unknown_fields) {
  UnknownFieldSetFieldSkipper skipper(unknown_fields);
  return ParseMessageSet(input, containing_type, &skipper);
}

int ExtensionSet::SpaceUsedExcludingSelf() const {
  int total_size =
      extensions_.size() * sizeof(map<int, Extension>::value_type);
  for (map<int, Extension>::const_iterator iter = extensions_.begin(),
       end = extensions_.end();
       iter != end;
       ++iter) {
    total_size += iter->second.SpaceUsedExcludingSelf();
  }
  return total_size;
}

inline int ExtensionSet::RepeatedMessage_SpaceUsedExcludingSelf(
    RepeatedPtrFieldBase* field) {
  return field->SpaceUsedExcludingSelf<GenericTypeHandler<Message> >();
}

int ExtensionSet::Extension::SpaceUsedExcludingSelf() const {
  int total_size = 0;
  if (is_repeated) {
    switch (cpp_type(type)) {
#define HANDLE_TYPE(UPPERCASE, LOWERCASE)                          \
      case WireFormatLite::CPPTYPE_##UPPERCASE:                    \
        total_size += sizeof(*repeated_##LOWERCASE##_value) +      \
            repeated_##LOWERCASE##_value->SpaceUsedExcludingSelf();\
        break

      HANDLE_TYPE(  INT32,   int32);
      HANDLE_TYPE(  INT64,   int64);
      HANDLE_TYPE( UINT32,  uint32);
      HANDLE_TYPE( UINT64,  uint64);
      HANDLE_TYPE(  FLOAT,   float);
      HANDLE_TYPE( DOUBLE,  double);
      HANDLE_TYPE(   BOOL,    bool);
      HANDLE_TYPE(   ENUM,    enum);
      HANDLE_TYPE( STRING,  string);

      case WireFormatLite::CPPTYPE_MESSAGE:
        // repeated_message_value is actually a RepeatedPtrField<MessageLite>,
        // but MessageLite has no SpaceUsed(), so we must directly call
        // RepeatedPtrFieldBase::SpaceUsedExcludingSelf() with a different type
        // handler.
        total_size += sizeof(*repeated_message_value) +
            RepeatedMessage_SpaceUsedExcludingSelf(repeated_message_value);
        break;
    }
  } else {
    switch (cpp_type(type)) {
      case WireFormatLite::CPPTYPE_STRING:
        total_size += sizeof(*string_value) +
                      StringSpaceUsedExcludingSelf(*string_value);
        break;
      case WireFormatLite::CPPTYPE_MESSAGE:
        total_size += down_cast<Message*>(message_value)->SpaceUsed();
        break;
      default:
        // No extra storage costs for primitive types.
        break;
    }
  }
  return total_size;
}

}  // namespace internal
}  // namespace protobuf
}  // namespace google