//===- StringEntry.h ------------------------------------------------------===//
//
//                     The MCLinker Project
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef MCLD_ADT_STRINGENTRY_H_
#define MCLD_ADT_STRINGENTRY_H_

#include <llvm/ADT/StringRef.h>
#include <llvm/Support/DataTypes.h>

#include <cassert>
#include <cstdlib>
#include <cstring>

namespace mcld {
template <typename DataType>
class StringEntryFactory;

/** \class StringEntry
 *  \brief StringEntry is a pair of strings which is designed for high locality.
 */
template <typename DataType>
class StringEntry {
 public:
  typedef llvm::StringRef key_type;
  typedef DataType value_type;

 public:
  key_type key() { return key_type(m_Key, m_KeyLen); }

  const key_type key() const { return key_type(m_Key, m_KeyLen); }

  value_type& value() { return m_Value; }

  const value_type& value() const { return m_Value; }

  size_t getKeyLength() const { return m_KeyLen; }

  size_t getValueLength() const { return m_Value.size(); }

  void setValue(const DataType& pVal) { m_Value = pVal; }

  bool compare(const llvm::StringRef& pX) { return key().equals(pX); }

  bool compare(const llvm::StringRef& pX) const { return key().equals(pX); }

 private:
  StringEntry();
  explicit StringEntry(const key_type& pKey);
  StringEntry(const StringEntry& pCopy);
  ~StringEntry();

 private:
  DataType m_Value;
  uint16_t m_KeyLen;
  char m_Key[];

  friend class StringEntryFactory<DataType>;
};

template <>
class StringEntry<llvm::StringRef> {
 public:
  typedef llvm::StringRef key_type;
  typedef llvm::StringRef value_type;

 public:
  key_type key() { return key_type(m_Key, m_KeyLen); }

  const key_type key() const { return key_type(m_Key, m_KeyLen); }

  value_type& value() { return m_Value; }

  const value_type& value() const { return m_Value; }

  size_t getKeyLength() const { return m_KeyLen; }

  size_t getValueLength() const { return m_Value.size(); }

  void setValue(const std::string& pVal) { setValue(pVal.c_str()); }

  void setValue(const char* pVal);

  void setValue(llvm::StringRef pVal);

  bool compare(const llvm::StringRef pX) { return key().equals(pX); }

  bool compare(const llvm::StringRef pX) const { return key().equals(pX); }

 private:
  StringEntry();
  explicit StringEntry(const key_type& pKey);
  StringEntry(const StringEntry& pCopy);
  ~StringEntry();

 private:
  llvm::StringRef m_Value;
  uint16_t m_KeyLen;
  char m_Key[];

  friend class StringEntryFactory<llvm::StringRef>;
};

template <typename DataType>
class StringEntryFactory {
 public:
  typedef StringEntry<DataType> entry_type;
  typedef typename StringEntry<DataType>::key_type key_type;
  typedef typename StringEntry<DataType>::value_type value_type;

 public:
  StringEntryFactory();
  ~StringEntryFactory();

  StringEntry<DataType>* produce(const key_type& pKey);
  void destroy(StringEntry<DataType>* pEntry);
};

#include "StringEntry.tcc"

}  // namespace mcld

#endif  // MCLD_ADT_STRINGENTRY_H_