// Copyright (c) 2006-2008 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 "skia/ext/skia_utils_win.h"

#include <stddef.h>
#include <windows.h>

#include "third_party/skia/include/core/SkRect.h"
#include "third_party/skia/include/core/SkTypes.h"
#include "third_party/skia/include/effects/SkGradientShader.h"

namespace {

static_assert(offsetof(RECT, left) == offsetof(SkIRect, fLeft), "o1");
static_assert(offsetof(RECT, top) == offsetof(SkIRect, fTop), "o2");
static_assert(offsetof(RECT, right) == offsetof(SkIRect, fRight), "o3");
static_assert(offsetof(RECT, bottom) == offsetof(SkIRect, fBottom), "o4");
static_assert(sizeof(RECT().left) == sizeof(SkIRect().fLeft), "o5");
static_assert(sizeof(RECT().top) == sizeof(SkIRect().fTop), "o6");
static_assert(sizeof(RECT().right) == sizeof(SkIRect().fRight), "o7");
static_assert(sizeof(RECT().bottom) == sizeof(SkIRect().fBottom), "o8");
static_assert(sizeof(RECT) == sizeof(SkIRect), "o9");

}  // namespace

namespace skia {

POINT SkPointToPOINT(const SkPoint& point) {
  POINT win_point = {
      SkScalarRoundToInt(point.fX), SkScalarRoundToInt(point.fY)
  };
  return win_point;
}

SkRect RECTToSkRect(const RECT& rect) {
  SkRect sk_rect = { SkIntToScalar(rect.left), SkIntToScalar(rect.top),
                     SkIntToScalar(rect.right), SkIntToScalar(rect.bottom) };
  return sk_rect;
}

SkColor COLORREFToSkColor(COLORREF color) {
#ifndef _MSC_VER
  return SkColorSetRGB(GetRValue(color), GetGValue(color), GetBValue(color));
#else
  // ARGB = 0xFF000000 | ((0BGR -> RGB0) >> 8)
  return 0xFF000000u | (_byteswap_ulong(color) >> 8);
#endif
}

COLORREF SkColorToCOLORREF(SkColor color) {
#ifndef _MSC_VER
  return RGB(SkColorGetR(color), SkColorGetG(color), SkColorGetB(color));
#else
  // 0BGR = ((ARGB -> BGRA) >> 8)
  return (_byteswap_ulong(color) >> 8);
#endif
}

void InitializeDC(HDC context) {
  // Enables world transformation.
  // If the GM_ADVANCED graphics mode is set, GDI always draws arcs in the
  // counterclockwise direction in logical space. This is equivalent to the
  // statement that, in the GM_ADVANCED graphics mode, both arc control points
  // and arcs themselves fully respect the device context's world-to-device
  // transformation.
  BOOL res = SetGraphicsMode(context, GM_ADVANCED);
  SkASSERT(res != 0);

  // Enables dithering.
  res = SetStretchBltMode(context, HALFTONE);
  SkASSERT(res != 0);
  // As per SetStretchBltMode() documentation, SetBrushOrgEx() must be called
  // right after.
  res = SetBrushOrgEx(context, 0, 0, NULL);
  SkASSERT(res != 0);

  // Sets up default orientation.
  res = SetArcDirection(context, AD_CLOCKWISE);
  SkASSERT(res != 0);

  // Sets up default colors.
  res = SetBkColor(context, RGB(255, 255, 255));
  SkASSERT(res != CLR_INVALID);
  res = SetTextColor(context, RGB(0, 0, 0));
  SkASSERT(res != CLR_INVALID);
  res = SetDCBrushColor(context, RGB(255, 255, 255));
  SkASSERT(res != CLR_INVALID);
  res = SetDCPenColor(context, RGB(0, 0, 0));
  SkASSERT(res != CLR_INVALID);

  // Sets up default transparency.
  res = SetBkMode(context, OPAQUE);
  SkASSERT(res != 0);
  res = SetROP2(context, R2_COPYPEN);
  SkASSERT(res != 0);
}

}  // namespace skia