// Copyright 2014 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 "core/css/MediaValues.h"

#include "core/css/CSSHelper.h"
#include "core/css/MediaValuesCached.h"
#include "core/css/MediaValuesDynamic.h"
#include "core/dom/Document.h"
#include "core/dom/Element.h"
#include "core/frame/FrameHost.h"
#include "core/frame/FrameView.h"
#include "core/frame/LocalFrame.h"
#include "core/frame/Settings.h"
#include "core/html/imports/HTMLImportsController.h"
#include "core/layout/LayoutObject.h"
#include "core/layout/api/LayoutViewItem.h"
#include "core/layout/compositing/PaintLayerCompositor.h"
#include "core/page/ChromeClient.h"
#include "core/page/Page.h"
#include "core/style/ComputedStyle.h"
#include "public/platform/WebScreenInfo.h"

namespace blink {

MediaValues* MediaValues::createDynamicIfFrameExists(LocalFrame* frame) {
  if (frame)
    return MediaValuesDynamic::create(frame);
  return MediaValuesCached::create();
}

double MediaValues::calculateViewportWidth(LocalFrame* frame) {
  ASSERT(frame && frame->view() && frame->document());
  int viewportWidth = frame->view()->layoutSize(IncludeScrollbars).width();
  return adjustDoubleForAbsoluteZoom(
      viewportWidth, frame->document()->layoutViewItem().styleRef());
}

double MediaValues::calculateViewportHeight(LocalFrame* frame) {
  ASSERT(frame && frame->view() && frame->document());
  int viewportHeight = frame->view()->layoutSize(IncludeScrollbars).height();
  return adjustDoubleForAbsoluteZoom(
      viewportHeight, frame->document()->layoutViewItem().styleRef());
}

int MediaValues::calculateDeviceWidth(LocalFrame* frame) {
  ASSERT(frame && frame->view() && frame->settings() && frame->host());
  blink::WebScreenInfo screenInfo = frame->host()->chromeClient().screenInfo();
  int deviceWidth = screenInfo.rect.width;
  if (frame->settings()->reportScreenSizeInPhysicalPixelsQuirk())
    deviceWidth = lroundf(deviceWidth * screenInfo.deviceScaleFactor);
  return deviceWidth;
}

int MediaValues::calculateDeviceHeight(LocalFrame* frame) {
  ASSERT(frame && frame->view() && frame->settings() && frame->host());
  blink::WebScreenInfo screenInfo = frame->host()->chromeClient().screenInfo();
  int deviceHeight = screenInfo.rect.height;
  if (frame->settings()->reportScreenSizeInPhysicalPixelsQuirk())
    deviceHeight = lroundf(deviceHeight * screenInfo.deviceScaleFactor);
  return deviceHeight;
}

bool MediaValues::calculateStrictMode(LocalFrame* frame) {
  ASSERT(frame && frame->document());
  return !frame->document()->inQuirksMode();
}

float MediaValues::calculateDevicePixelRatio(LocalFrame* frame) {
  return frame->devicePixelRatio();
}

int MediaValues::calculateColorBitsPerComponent(LocalFrame* frame) {
  ASSERT(frame && frame->page() && frame->page()->mainFrame());
  if (!frame->page()->mainFrame()->isLocalFrame() ||
      frame->host()->chromeClient().screenInfo().isMonochrome)
    return 0;
  return frame->host()->chromeClient().screenInfo().depthPerComponent;
}

int MediaValues::calculateMonochromeBitsPerComponent(LocalFrame* frame) {
  ASSERT(frame && frame->page() && frame->page()->mainFrame());
  if (!frame->page()->mainFrame()->isLocalFrame() ||
      !frame->host()->chromeClient().screenInfo().isMonochrome)
    return 0;
  return frame->host()->chromeClient().screenInfo().depthPerComponent;
}

int MediaValues::calculateDefaultFontSize(LocalFrame* frame) {
  return frame->host()->settings().defaultFontSize();
}

const String MediaValues::calculateMediaType(LocalFrame* frame) {
  ASSERT(frame);
  if (!frame->view())
    return emptyAtom;
  return frame->view()->mediaType();
}

WebDisplayMode MediaValues::calculateDisplayMode(LocalFrame* frame) {
  ASSERT(frame);
  WebDisplayMode mode = frame->host()->settings().displayModeOverride();

  if (mode != WebDisplayModeUndefined)
    return mode;

  if (!frame->view())
    return WebDisplayModeBrowser;

  return frame->view()->displayMode();
}

bool MediaValues::calculateThreeDEnabled(LocalFrame* frame) {
  ASSERT(frame && !frame->contentLayoutItem().isNull() &&
         frame->contentLayoutItem().compositor());
  bool threeDEnabled = false;
  if (LayoutViewItem view = frame->contentLayoutItem())
    threeDEnabled = view.compositor()->hasAcceleratedCompositing();
  return threeDEnabled;
}

PointerType MediaValues::calculatePrimaryPointerType(LocalFrame* frame) {
  ASSERT(frame && frame->settings());
  return frame->settings()->primaryPointerType();
}

int MediaValues::calculateAvailablePointerTypes(LocalFrame* frame) {
  ASSERT(frame && frame->settings());
  return frame->settings()->availablePointerTypes();
}

HoverType MediaValues::calculatePrimaryHoverType(LocalFrame* frame) {
  ASSERT(frame && frame->settings());
  return frame->settings()->primaryHoverType();
}

int MediaValues::calculateAvailableHoverTypes(LocalFrame* frame) {
  ASSERT(frame && frame->settings());
  return frame->settings()->availableHoverTypes();
}

bool MediaValues::computeLengthImpl(double value,
                                    CSSPrimitiveValue::UnitType type,
                                    unsigned defaultFontSize,
                                    double viewportWidth,
                                    double viewportHeight,
                                    double& result) {
  // The logic in this function is duplicated from
  // CSSToLengthConversionData::zoomedComputedPixels() because
  // MediaValues::computeLength() needs nearly identical logic, but we haven't
  // found a way to make CSSToLengthConversionData::zoomedComputedPixels() more
  // generic (to solve both cases) without hurting performance.
  // FIXME - Unite the logic here with CSSToLengthConversionData in a performant
  // way.
  switch (type) {
    case CSSPrimitiveValue::UnitType::Ems:
    case CSSPrimitiveValue::UnitType::Rems:
      result = value * defaultFontSize;
      return true;
    case CSSPrimitiveValue::UnitType::Pixels:
    case CSSPrimitiveValue::UnitType::UserUnits:
      result = value;
      return true;
    case CSSPrimitiveValue::UnitType::Exs:
    // FIXME: We have a bug right now where the zoom will be applied twice to EX
    // units.
    case CSSPrimitiveValue::UnitType::Chs:
      // FIXME: We don't seem to be able to cache fontMetrics related values.
      // Trying to access them is triggering some sort of microtask. Serving the
      // spec's default instead.
      result = (value * defaultFontSize) / 2.0;
      return true;
    case CSSPrimitiveValue::UnitType::ViewportWidth:
      result = (value * viewportWidth) / 100.0;
      return true;
    case CSSPrimitiveValue::UnitType::ViewportHeight:
      result = (value * viewportHeight) / 100.0;
      return true;
    case CSSPrimitiveValue::UnitType::ViewportMin:
      result = (value * std::min(viewportWidth, viewportHeight)) / 100.0;
      return true;
    case CSSPrimitiveValue::UnitType::ViewportMax:
      result = (value * std::max(viewportWidth, viewportHeight)) / 100.0;
      return true;
    case CSSPrimitiveValue::UnitType::Centimeters:
      result = value * cssPixelsPerCentimeter;
      return true;
    case CSSPrimitiveValue::UnitType::Millimeters:
      result = value * cssPixelsPerMillimeter;
      return true;
    case CSSPrimitiveValue::UnitType::Inches:
      result = value * cssPixelsPerInch;
      return true;
    case CSSPrimitiveValue::UnitType::Points:
      result = value * cssPixelsPerPoint;
      return true;
    case CSSPrimitiveValue::UnitType::Picas:
      result = value * cssPixelsPerPica;
      return true;
    default:
      return false;
  }
}

LocalFrame* MediaValues::frameFrom(Document& document) {
  Document* executingDocument = document.importsController()
                                    ? document.importsController()->master()
                                    : &document;
  ASSERT(executingDocument);
  return executingDocument->frame();
}

}  // namespace blink