// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/base/range/range.h"

#include <limits>
#include <ostream>

#include "base/logging.h"

namespace ui {

Range::Range()
    : start_(0),
      end_(0) {
}

Range::Range(size_t start, size_t end)
    : start_(start),
      end_(end) {
}

Range::Range(size_t position)
    : start_(position),
      end_(position) {
}

// static
const Range Range::InvalidRange() {
  return Range(std::numeric_limits<size_t>::max());
}

bool Range::IsValid() const {
  return *this != InvalidRange();
}

size_t Range::GetMin() const {
  return std::min(start(), end());
}

size_t Range::GetMax() const {
  return std::max(start(), end());
}

bool Range::operator==(const Range& other) const {
  return start() == other.start() && end() == other.end();
}

bool Range::operator!=(const Range& other) const {
  return !(*this == other);
}

bool Range::EqualsIgnoringDirection(const Range& other) const {
  return GetMin() == other.GetMin() && GetMax() == other.GetMax();
}

#if defined(OS_WIN)
Range::Range(const CHARRANGE& range, LONG total_length) {
  // Check if this is an invalid range.
  if (range.cpMin == -1 && range.cpMax == -1) {
    *this = InvalidRange();
  } else {
    DCHECK_GE(range.cpMin, 0);
    set_start(range.cpMin);
    // {0,-1} is the "whole range" but that doesn't mean much out of context,
    // so use the |total_length| parameter.
    if (range.cpMax == -1) {
      DCHECK_EQ(0, range.cpMin);
      DCHECK_NE(-1, total_length);
      set_end(total_length);
    } else {
      set_end(range.cpMax);
    }
  }
}

CHARRANGE Range::ToCHARRANGE() const {
  CHARRANGE r = { -1, -1 };
  if (!IsValid())
    return r;

  const LONG kLONGMax = std::numeric_limits<LONG>::max();
  DCHECK_LE(static_cast<LONG>(start()), kLONGMax);
  DCHECK_LE(static_cast<LONG>(end()), kLONGMax);
  r.cpMin = start();
  r.cpMax = end();
  return r;
}
#endif  // defined(OS_WIN)

std::ostream& operator<<(std::ostream& out, const ui::Range& range) {
  return out << "{" << range.start() << "," << range.end() << "}";
}

}  // namespace gfx