/*
 * Copyright (c) 2003-2009, John Wiegley.  All rights reserved.
 *
 * 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 New Artisans LLC 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
 * (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 _ERROR_H
#define _ERROR_H

namespace ledger {

extern std::ostringstream _desc_buffer;

template <typename T>
inline void throw_func(const string& message) {
  _desc_buffer.str("");
  throw T(message);
}

#define throw_(cls, msg)					\
  ((_desc_buffer << msg), throw_func<cls>(_desc_buffer.str()))

extern std::ostringstream _ctxt_buffer;

#define add_error_context(msg)					\
  ((long(_ctxt_buffer.tellp()) == 0) ?				\
   (_ctxt_buffer << msg) : (_ctxt_buffer << std::endl << msg))

inline string error_context() {
  string context = _ctxt_buffer.str();
  _ctxt_buffer.str("");
  return context;
}

inline string file_context(const path& file, std::size_t line) {
  std::ostringstream buf;
  buf << "\"" << file << "\", line " << line << ": ";
  return buf.str();
}

inline string line_context(const string&    line,
			   istream_pos_type pos     = istream_pos_type(0),
			   istream_pos_type end_pos = istream_pos_type(0))
{
  std::ostringstream buf;
  buf << "  " << line << "\n";

  if (pos != istream_pos_type(0)) {
    buf << "  ";
    if (end_pos == istream_pos_type(0)) {
      for (istream_pos_type i = 0; i < pos; i += 1)
	buf << " ";
      buf << "^\n";
    } else {
      for (istream_pos_type i = 0; i < end_pos; i += 1) {
	if (i >= pos)
	  buf << "^";
	else
	  buf << " ";
      }
      buf << '\n';
    }
  }
  return buf.str();
}

#define DECLARE_EXCEPTION(name, kind)				\
  class name : public kind {					\
  public:							\
  explicit name(const string& why) throw() : kind(why) {}	\
  virtual ~name() throw() {}					\
  }

} // namespace ledger

#endif // _ERROR_H