/******************************************************************************
 * Top contributors (to current version):
 *   Tim King, Morgan Deters, Gereon Kremer
 *
 * This file is part of the cvc5 project.
 *
 * Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
 * in the top-level source directory and their institutional affiliations.
 * All rights reserved.  See the file COPYING in the top-level source
 * directory for licensing information.
 * ****************************************************************************
 *
 * cvc5's exception base class and some associated utilities.
 */

#include "base/exception.h"

#include <cstdarg>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <sstream>
#include <string>

#include "base/check.h"

using namespace std;

namespace cvc5 {

std::string Exception::toString() const
{
  std::stringstream ss;
  toStream(ss);
  return ss.str();
}

thread_local LastExceptionBuffer* LastExceptionBuffer::s_currentBuffer = nullptr;

LastExceptionBuffer::LastExceptionBuffer() : d_contents(nullptr) {}

LastExceptionBuffer::~LastExceptionBuffer() {
  if(d_contents != nullptr){
    free(d_contents);
    d_contents = nullptr;
  }
}

void LastExceptionBuffer::setContents(const char* string) {
  if(d_contents != nullptr){
    free(d_contents);
    d_contents = nullptr;
  }

  if(string != nullptr){
    d_contents = strdup(string);
  }
}

const char* IllegalArgumentException::s_header = "Illegal argument detected";

std::string IllegalArgumentException::formatVariadic() {
  return std::string();
}

std::string IllegalArgumentException::formatVariadic(const char* format, ...) {
  va_list args;
  va_start(args, format);

  int n = 512;
  char* buf = nullptr;

  for (int i = 0; i < 2; ++i){
    Assert(n > 0);
    delete[] buf;
    buf = new char[n];

    va_list args_copy;
    va_copy(args_copy, args);
    int size = vsnprintf(buf, n, format, args);
    va_end(args_copy);

    if(size >= n){
      buf[n-1] = '\0';
      n = size + 1;
    } else {
      break;
    }
  }
  // buf is not nullptr is an invariant.
  // buf is also 0 terminated.
  Assert(buf != nullptr);
  std::string result(buf);
  delete [] buf;
  va_end(args);
  return result;
}

std::string IllegalArgumentException::format_extra(const char* condStr, const char* argDesc){
  return ( std::string("`") + argDesc + "' is a bad argument"
           + (*condStr == '\0' ? std::string() :
              ( std::string("; expected ") +
                condStr + " to hold" )) );
}

void IllegalArgumentException::construct(const char* header, const char* extra,
                                         const char* function, const char* tail) {
  // try building the exception msg with a smallish buffer first,
  // then with a larger one if sprintf tells us to.
  int n = 512;
  char* buf;

  for(;;) {
    buf = new char[n];

    int size;
    if(extra == nullptr) {
      size = snprintf(buf, n, "%s\n%s\n%s",
                      header, function, tail);
    } else {
      size = snprintf(buf, n, "%s\n%s\n\n  %s\n%s",
                      header, function, extra, tail);
    }

    if(size < n) {
      break;
    } else {
      // size >= n
      // try again with a buffer that's large enough
      n = size + 1;
      delete [] buf;
    }
  }

  setMessage(string(buf));

#ifdef CVC5_DEBUG
  LastExceptionBuffer* buffer = LastExceptionBuffer::getCurrent();
  if(buffer != nullptr){
    if(buffer->getContents() == nullptr) {
      buffer->setContents(buf);
    }
  }
#endif /* CVC5_DEBUG */
  delete [] buf;
}

void IllegalArgumentException::construct(const char* header, const char* extra,
                                         const char* function) {
  // try building the exception msg with a smallish buffer first,
  // then with a larger one if sprintf tells us to.
  int n = 256;
  char* buf;

  for(;;) {
    buf = new char[n];

    int size;
    if(extra == nullptr) {
      size = snprintf(buf, n, "%s.\n%s\n",
                      header, function);
    } else {
      size = snprintf(buf, n, "%s.\n%s\n\n  %s\n",
                      header, function, extra);
    }

    if(size < n) {
      break;
    } else {
      // try again with a buffer that's large enough
      n = size + 1;
      delete [] buf;
    }
  }

  setMessage(string(buf));

#ifdef CVC5_DEBUG
  LastExceptionBuffer* buffer = LastExceptionBuffer::getCurrent();
  if(buffer != nullptr){
    if(buffer->getContents() == nullptr) {
      buffer->setContents(buf);
    }
  }
#endif /* CVC5_DEBUG */
  delete [] buf;
}

}  // namespace cvc5