You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

139 lines
4.4 KiB

// 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.
#ifndef UI_GFX_RANGE_RANGE_H_
#define UI_GFX_RANGE_RANGE_H_
#include <stddef.h>
#include <stdint.h>
#include <limits>
#include <ostream>
#include <string>
#include "build/build_config.h"
#include "ui/gfx/range/gfx_range_export.h"
#if defined(OS_MACOSX)
#if __OBJC__
#import <Foundation/Foundation.h>
#else
typedef struct _NSRange NSRange;
#endif
#endif // defined(OS_MACOSX)
#if defined(OS_WIN)
typedef struct _charrange CHARRANGE;
#endif
namespace gfx {
// A Range contains two integer values that represent a numeric range, like the
// range of characters in a text selection. A range is made of a start and end
// position; when they are the same, the Range is akin to a caret. Note that
// |start_| can be greater than |end_| to respect the directionality of the
// range.
class GFX_RANGE_EXPORT Range {
public:
// Creates an empty range {0,0}.
constexpr Range() : Range(0) {}
// Initializes the range with a start and end.
constexpr Range(uint32_t start, uint32_t end) : start_(start), end_(end) {}
// Initializes the range with the same start and end positions.
constexpr explicit Range(uint32_t position) : Range(position, position) {}
// Platform constructors.
#if defined(OS_MACOSX)
explicit Range(const NSRange& range);
#elif defined(OS_WIN)
// The |total_length| paramater should be used if the CHARRANGE is set to
// {0,-1} to indicate the whole range.
Range(const CHARRANGE& range, long total_length = -1);
#endif
// Returns a range that is invalid, which is {UINT32_MAX,UINT32_MAX}.
static constexpr Range InvalidRange() {
return Range(std::numeric_limits<uint32_t>::max());
}
// Checks if the range is valid through comparison to InvalidRange().
constexpr bool IsValid() const { return *this != InvalidRange(); }
// Getters and setters.
constexpr uint32_t start() const { return start_; }
void set_start(uint32_t start) { start_ = start; }
constexpr uint32_t end() const { return end_; }
void set_end(uint32_t end) { end_ = end; }
// Returns the absolute value of the length.
constexpr uint32_t length() const { return GetMax() - GetMin(); }
constexpr bool is_reversed() const { return start() > end(); }
constexpr bool is_empty() const { return start() == end(); }
// Returns the minimum and maximum values.
constexpr uint32_t GetMin() const {
return start() < end() ? start() : end();
}
constexpr uint32_t GetMax() const {
return start() > end() ? start() : end();
}
constexpr bool operator==(const Range& other) const {
return start() == other.start() && end() == other.end();
}
constexpr bool operator!=(const Range& other) const {
return !(*this == other);
}
constexpr bool EqualsIgnoringDirection(const Range& other) const {
return GetMin() == other.GetMin() && GetMax() == other.GetMax();
}
// Returns true if this range intersects the specified |range|.
constexpr bool Intersects(const Range& range) const {
return IsValid() && range.IsValid() &&
!(range.GetMax() < GetMin() || range.GetMin() >= GetMax());
}
// Returns true if this range contains the specified |range|.
constexpr bool Contains(const Range& range) const {
return IsValid() && range.IsValid() && GetMin() <= range.GetMin() &&
range.GetMax() <= GetMax();
}
// Computes the intersection of this range with the given |range|.
// If they don't intersect, it returns an InvalidRange().
// The returned range is always empty or forward (never reversed).
Range Intersect(const Range& range) const;
#if defined(OS_MACOSX)
Range& operator=(const NSRange& range);
// NSRange does not store the directionality of a range, so if this
// is_reversed(), the range will get flipped when converted to an NSRange.
NSRange ToNSRange() const;
#elif defined(OS_WIN)
CHARRANGE ToCHARRANGE() const;
#endif
// GTK+ has no concept of a range.
std::string ToString() const;
private:
// Note: we use uint32_t instead of size_t because this struct is sent over
// IPC which could span 32 & 64 bit processes. This is fine since text spans
// shouldn't exceed UINT32_MAX even on 64 bit builds.
uint32_t start_;
uint32_t end_;
};
GFX_RANGE_EXPORT std::ostream& operator<<(std::ostream& os, const Range& range);
} // namespace gfx
#endif // UI_GFX_RANGE_RANGE_H_