//===-- LibCxxInitializerList.cpp -----------------------------------------===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

#include "LibCxx.h"

#include "lldb/Core/ValueObject.h"

#include "lldb/DataFormatters/FormattersHelpers.h"

#include "lldb/Utility/ConstString.h"

#include <optional>

using namespace lldb;

using namespace lldb_private;

using namespace lldb_private::formatters;

namespace lldb_private {

namespace formatters {

class LibcxxInitializerListSyntheticFrontEnd

    : public SyntheticChildrenFrontEnd {

public:

  LibcxxInitializerListSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);

  ~LibcxxInitializerListSyntheticFrontEnd() override;

  size_t CalculateNumChildren() override;

  lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;

  bool Update() override;

  bool MightHaveChildren() override;

  size_t GetIndexOfChildWithName(ConstString name) override;

private:

  ValueObject *m_start = nullptr;

  CompilerType m_element_type;

  uint32_t m_element_size = 0;

  size_t m_num_elements = 0;

};

} // namespace formatters

} // namespace lldb_private

lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::

    LibcxxInitializerListSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)

    : SyntheticChildrenFrontEnd(*valobj_sp), m_element_type() {

  if (valobj_sp)

    Update();

}

lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::

    ~LibcxxInitializerListSyntheticFrontEnd() {

  // this needs to stay around because it's a child object who will follow its

  // parent's life cycle

  // delete m_start;

}

size_t lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::

    CalculateNumChildren() {

  m_num_elements = 0;

  ValueObjectSP size_sp(m_backend.GetChildMemberWithName("__size_"));

  if (size_sp)

    m_num_elements = size_sp->GetValueAsUnsigned(0);

  return m_num_elements;

}

lldb::ValueObjectSP lldb_private::formatters::

    LibcxxInitializerListSyntheticFrontEnd::GetChildAtIndex(size_t idx) {

  if (!m_start)

    return lldb::ValueObjectSP();

  uint64_t offset = idx * m_element_size;

  offset = offset + m_start->GetValueAsUnsigned(0);

  StreamString name;

  name.Printf("[%" PRIu64 "]", (uint64_t)idx);

  return CreateValueObjectFromAddress(name.GetString(), offset,

                                      m_backend.GetExecutionContextRef(),

                                      m_element_type);

}

bool lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::

    Update() {

  m_start = nullptr;

  m_num_elements = 0;

  m_element_type = m_backend.GetCompilerType().GetTypeTemplateArgument(0);

  if (!m_element_type.IsValid())

    return false;

  if (std::optional<uint64_t> size = m_element_type.GetByteSize(nullptr)) {

    m_element_size = *size;

    // Store raw pointers or end up with a circular dependency.

    m_start = m_backend.GetChildMemberWithName("__begin_").get();

  }

  return false;

}

bool lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::

    MightHaveChildren() {

  return true;

}

size_t lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::

    GetIndexOfChildWithName(ConstString name) {

  if (!m_start)

    return UINT32_MAX;

  return ExtractIndexFromString(name.GetCString());

}

lldb_private::SyntheticChildrenFrontEnd *

lldb_private::formatters::LibcxxInitializerListSyntheticFrontEndCreator(

    CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {

  return (valobj_sp ? new LibcxxInitializerListSyntheticFrontEnd(valobj_sp)

                    : 
nullptr0
);

}