// Copyright (c) 2012 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/gfx/range/range.h"

#include <algorithm>
#include <limits>

#include "base/format_macros.h"
#include "base/logging.h"
#include "base/strings/stringprintf.h"

namespace gfx {

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();
}

bool Range::Intersects(const Range& range) const {
  return IsValid() && range.IsValid() &&
      !(range.GetMax() < GetMin() || range.GetMin() >= GetMax());
}

bool Range::Contains(const Range& range) const {
  return IsValid() && range.IsValid() &&
      GetMin() <= range.GetMin() && range.GetMax() <= GetMax();
}

Range Range::Intersect(const Range& range) const {
  size_t min = std::max(GetMin(), range.GetMin());
  size_t max = std::min(GetMax(), range.GetMax());

  if (min >= max)  // No intersection.
    return InvalidRange();

  return Range(min, max);
}

std::string Range::ToString() const {
  return base::StringPrintf("{%" PRIuS ",%" PRIuS "}", start(), end());
}

std::ostream& operator<<(std::ostream& os, const Range& range) {
  return os << range.ToString();
}

}  // namespace gfx