Source/web/DevToolsEmulator.cpp

// Copyright 2015 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 "config.h"
#include "web/DevToolsEmulator.h"

#include "core/frame/FrameHost.h"
#include "core/frame/FrameView.h"
#include "core/frame/Settings.h"
#include "core/page/Page.h"
#include "platform/RuntimeEnabledFeatures.h"
#include "public/platform/WebLayerTreeView.h"
#include "public/web/WebDeviceEmulationParams.h"
#include "web/InspectorEmulationAgent.h"
#include "web/WebInputEventConversion.h"
#include "web/WebLocalFrameImpl.h"
#include "web/WebSettingsImpl.h"
#include "web/WebViewImpl.h"

namespace {

static float calculateDeviceScaleAdjustment(int width, int height, float deviceScaleFactor)
{
    // Chromium on Android uses a device scale adjustment for fonts used in text autosizing for
    // improved legibility. This function computes this adjusted value for text autosizing.
    // For a description of the Android device scale adjustment algorithm, see:
    // chrome/browser/chrome_content_browser_client.cc, GetDeviceScaleAdjustment(...)
    if (!width || !height || !deviceScaleFactor)
        return 1;

    static const float kMinFSM = 1.05f;
    static const int kWidthForMinFSM = 320;
    static const float kMaxFSM = 1.3f;
    static const int kWidthForMaxFSM = 800;

    float minWidth = std::min(width, height) / deviceScaleFactor;
    if (minWidth <= kWidthForMinFSM)
        return kMinFSM;
    if (minWidth >= kWidthForMaxFSM)
        return kMaxFSM;

    // The font scale multiplier varies linearly between kMinFSM and kMaxFSM.
    float ratio = static_cast<float>(minWidth - kWidthForMinFSM) / (kWidthForMaxFSM - kWidthForMinFSM);
    return ratio * (kMaxFSM - kMinFSM) + kMinFSM;
}

} // namespace

namespace blink {

DevToolsEmulator::DevToolsEmulator(WebViewImpl* webViewImpl)
    : m_webViewImpl(webViewImpl)
    , m_emulationAgent(nullptr)
    , m_deviceMetricsEnabled(false)
    , m_emulateMobileEnabled(false)
    , m_isOverlayScrollbarsEnabled(false)
    , m_originalDefaultMinimumPageScaleFactor(0)
    , m_originalDefaultMaximumPageScaleFactor(0)
    , m_embedderTextAutosizingEnabled(webViewImpl->page()->settings().textAutosizingEnabled())
    , m_embedderDeviceScaleAdjustment(webViewImpl->page()->settings().deviceScaleAdjustment())
    , m_embedderPreferCompositingToLCDTextEnabled(webViewImpl->page()->settings().preferCompositingToLCDTextEnabled())
    , m_embedderUseMobileViewport(webViewImpl->page()->settings().useMobileViewportStyle())
    , m_embedderPluginsEnabled(webViewImpl->page()->settings().pluginsEnabled())
    , m_embedderAvailablePointerTypes(webViewImpl->page()->settings().availablePointerTypes())
    , m_embedderPrimaryPointerType(webViewImpl->page()->settings().primaryPointerType())
    , m_embedderAvailableHoverTypes(webViewImpl->page()->settings().availableHoverTypes())
    , m_embedderPrimaryHoverType(webViewImpl->page()->settings().primaryHoverType())
    , m_touchEventEmulationEnabled(false)
    , m_doubleTapToZoomEnabled(false)
    , m_originalTouchEnabled(false)
    , m_originalDeviceSupportsMouse(false)
    , m_originalDeviceSupportsTouch(false)
    , m_originalMaxTouchPoints(0)
    , m_embedderScriptEnabled(webViewImpl->page()->settings().scriptEnabled())
    , m_scriptExecutionDisabled(false)
    , m_hidePinchScrollbarsNearMinScale(false)
{
}

DevToolsEmulator::~DevToolsEmulator()
{
}

PassOwnPtrWillBeRawPtr<DevToolsEmulator> DevToolsEmulator::create(WebViewImpl* webViewImpl)
{
    return adoptPtrWillBeNoop(new DevToolsEmulator(webViewImpl));
}

DEFINE_TRACE(DevToolsEmulator)
{
    visitor->trace(m_emulationAgent);
}

void DevToolsEmulator::setEmulationAgent(InspectorEmulationAgent* agent)
{
    m_emulationAgent = agent;
}

void DevToolsEmulator::viewportChanged()
{
    if (m_emulationAgent)
        m_emulationAgent->viewportChanged();
}

void DevToolsEmulator::setTextAutosizingEnabled(bool enabled)
{
    m_embedderTextAutosizingEnabled = enabled;
    bool emulateMobileEnabled = m_deviceMetricsEnabled && m_emulateMobileEnabled;
    if (!emulateMobileEnabled)
        m_webViewImpl->page()->settings().setTextAutosizingEnabled(enabled);
}

void DevToolsEmulator::setDeviceScaleAdjustment(float deviceScaleAdjustment)
{
    m_embedderDeviceScaleAdjustment = deviceScaleAdjustment;
    bool emulateMobileEnabled = m_deviceMetricsEnabled && m_emulateMobileEnabled;
    if (!emulateMobileEnabled)
        m_webViewImpl->page()->settings().setDeviceScaleAdjustment(deviceScaleAdjustment);
}

void DevToolsEmulator::setPreferCompositingToLCDTextEnabled(bool enabled)
{
    m_embedderPreferCompositingToLCDTextEnabled = enabled;
    bool emulateMobileEnabled = m_deviceMetricsEnabled && m_emulateMobileEnabled;
    if (!emulateMobileEnabled)
        m_webViewImpl->page()->settings().setPreferCompositingToLCDTextEnabled(enabled);
}

void DevToolsEmulator::setUseMobileViewportStyle(bool enabled)
{
    m_embedderUseMobileViewport = enabled;
    bool emulateMobileEnabled = m_deviceMetricsEnabled && m_emulateMobileEnabled;
    if (!emulateMobileEnabled)
        m_webViewImpl->page()->settings().setUseMobileViewportStyle(enabled);
}

void DevToolsEmulator::setPluginsEnabled(bool enabled)
{
    m_embedderPluginsEnabled = enabled;
    bool emulateMobileEnabled = m_deviceMetricsEnabled && m_emulateMobileEnabled;
    if (!emulateMobileEnabled)
        m_webViewImpl->page()->settings().setPluginsEnabled(enabled);
}

void DevToolsEmulator::setScriptEnabled(bool enabled)
{
    m_embedderScriptEnabled = enabled;
    if (!m_scriptExecutionDisabled)
        m_webViewImpl->page()->settings().setScriptEnabled(enabled);
}

void DevToolsEmulator::setDoubleTapToZoomEnabled(bool enabled)
{
    m_doubleTapToZoomEnabled = enabled;
}

bool DevToolsEmulator::doubleTapToZoomEnabled() const
{
    return m_touchEventEmulationEnabled ? true : m_doubleTapToZoomEnabled;
}

void DevToolsEmulator::setHidePinchScrollbarsNearMinScale(bool enabled)
{
    m_hidePinchScrollbarsNearMinScale = enabled;
    if (m_webViewImpl->layerTreeView())
        m_webViewImpl->layerTreeView()->setHidePinchScrollbarsNearMinScale(enabled);
}

void DevToolsEmulator::setAvailablePointerTypes(int types)
{
    m_embedderAvailablePointerTypes = types;
    bool emulateMobileEnabled = m_deviceMetricsEnabled && m_emulateMobileEnabled;
    if (!emulateMobileEnabled)
        m_webViewImpl->page()->settings().setAvailablePointerTypes(types);
}

void DevToolsEmulator::setPrimaryPointerType(PointerType pointerType)
{
    m_embedderPrimaryPointerType = pointerType;
    bool emulateMobileEnabled = m_deviceMetricsEnabled && m_emulateMobileEnabled;
    if (!emulateMobileEnabled)
        m_webViewImpl->page()->settings().setPrimaryPointerType(pointerType);
}

void DevToolsEmulator::setAvailableHoverTypes(int types)
{
    m_embedderAvailableHoverTypes = types;
    bool emulateMobileEnabled = m_deviceMetricsEnabled && m_emulateMobileEnabled;
    if (!emulateMobileEnabled)
        m_webViewImpl->page()->settings().setAvailableHoverTypes(types);
}

void DevToolsEmulator::setPrimaryHoverType(HoverType hoverType)
{
    m_embedderPrimaryHoverType = hoverType;
    bool emulateMobileEnabled = m_deviceMetricsEnabled && m_emulateMobileEnabled;
    if (!emulateMobileEnabled)
        m_webViewImpl->page()->settings().setPrimaryHoverType(hoverType);
}

void DevToolsEmulator::enableDeviceEmulation(const WebDeviceEmulationParams& params)
{
    if (!m_deviceMetricsEnabled) {
        m_deviceMetricsEnabled = true;
        if (params.viewSize.width || params.viewSize.height)
            m_webViewImpl->setBackgroundColorOverride(Color::darkGray);
        m_webViewImpl->updateShowFPSCounter();
    }

    m_webViewImpl->page()->settings().setDeviceScaleAdjustment(calculateDeviceScaleAdjustment(params.viewSize.width, params.viewSize.height, params.deviceScaleFactor));

    if (params.screenPosition == WebDeviceEmulationParams::Mobile)
        enableMobileEmulation();
    else
        disableMobileEmulation();

    m_webViewImpl->setCompositorDeviceScaleFactorOverride(params.deviceScaleFactor);
    m_webViewImpl->setRootLayerTransform(WebSize(params.offset.x, params.offset.y), params.scale);
    if (Document* document = m_webViewImpl->mainFrameImpl()->frame()->document())
        document->mediaQueryAffectingValueChanged();
}

void DevToolsEmulator::disableDeviceEmulation()
{
    if (!m_deviceMetricsEnabled)
        return;

    m_deviceMetricsEnabled = false;
    m_webViewImpl->setBackgroundColorOverride(Color::transparent);
    m_webViewImpl->updateShowFPSCounter();
    m_webViewImpl->page()->settings().setDeviceScaleAdjustment(m_embedderDeviceScaleAdjustment);
    disableMobileEmulation();
    m_webViewImpl->setCompositorDeviceScaleFactorOverride(0.f);
    m_webViewImpl->setRootLayerTransform(WebSize(0.f, 0.f), 1.f);
    m_webViewImpl->setPageScaleFactor(1.f);
    if (Document* document = m_webViewImpl->mainFrameImpl()->frame()->document())
        document->mediaQueryAffectingValueChanged();
}

void DevToolsEmulator::enableMobileEmulation()
{
    if (m_emulateMobileEnabled)
        return;
    m_emulateMobileEnabled = true;
    m_isOverlayScrollbarsEnabled = RuntimeEnabledFeatures::overlayScrollbarsEnabled();
    RuntimeEnabledFeatures::setOverlayScrollbarsEnabled(true);
    m_webViewImpl->enableViewport();
    m_webViewImpl->settings()->setViewportMetaEnabled(true);
    m_webViewImpl->page()->frameHost().visualViewport().initializeScrollbars();
    m_webViewImpl->settings()->setShrinksViewportContentToFit(true);
    m_webViewImpl->page()->settings().setTextAutosizingEnabled(true);
    m_webViewImpl->page()->settings().setPreferCompositingToLCDTextEnabled(true);
    m_webViewImpl->page()->settings().setUseMobileViewportStyle(true);
    m_webViewImpl->page()->settings().setPluginsEnabled(false);
    m_webViewImpl->page()->settings().setAvailablePointerTypes(PointerTypeCoarse);
    m_webViewImpl->page()->settings().setPrimaryPointerType(PointerTypeCoarse);
    m_webViewImpl->page()->settings().setAvailableHoverTypes(HoverTypeOnDemand);
    m_webViewImpl->page()->settings().setPrimaryHoverType(HoverTypeOnDemand);
    m_webViewImpl->setZoomFactorOverride(1);

    m_originalDefaultMinimumPageScaleFactor = m_webViewImpl->defaultMinimumPageScaleFactor();
    m_originalDefaultMaximumPageScaleFactor = m_webViewImpl->defaultMaximumPageScaleFactor();
    m_webViewImpl->setDefaultPageScaleLimits(0.25f, 5);
}

void DevToolsEmulator::disableMobileEmulation()
{
    if (!m_emulateMobileEnabled)
        return;
    RuntimeEnabledFeatures::setOverlayScrollbarsEnabled(m_isOverlayScrollbarsEnabled);
    m_webViewImpl->disableViewport();
    m_webViewImpl->settings()->setViewportMetaEnabled(false);
    m_webViewImpl->page()->frameHost().visualViewport().initializeScrollbars();
    m_webViewImpl->settings()->setShrinksViewportContentToFit(false);
    m_webViewImpl->page()->settings().setTextAutosizingEnabled(m_embedderTextAutosizingEnabled);
    m_webViewImpl->page()->settings().setPreferCompositingToLCDTextEnabled(m_embedderPreferCompositingToLCDTextEnabled);
    m_webViewImpl->page()->settings().setUseMobileViewportStyle(m_embedderUseMobileViewport);
    m_webViewImpl->page()->settings().setPluginsEnabled(m_embedderPluginsEnabled);
    m_webViewImpl->page()->settings().setAvailablePointerTypes(m_embedderAvailablePointerTypes);
    m_webViewImpl->page()->settings().setPrimaryPointerType(m_embedderPrimaryPointerType);
    m_webViewImpl->page()->settings().setAvailableHoverTypes(m_embedderAvailableHoverTypes);
    m_webViewImpl->page()->settings().setPrimaryHoverType(m_embedderPrimaryHoverType);
    m_webViewImpl->setZoomFactorOverride(0);
    m_emulateMobileEnabled = false;
    m_webViewImpl->setDefaultPageScaleLimits(
        m_originalDefaultMinimumPageScaleFactor,
        m_originalDefaultMaximumPageScaleFactor);
}

void DevToolsEmulator::setTouchEventEmulationEnabled(bool enabled)
{
    if (m_touchEventEmulationEnabled == enabled)
        return;
    if (!m_touchEventEmulationEnabled) {
        m_originalTouchEnabled = RuntimeEnabledFeatures::touchEnabled();
        m_originalDeviceSupportsMouse = m_webViewImpl->page()->settings().deviceSupportsMouse();
        m_originalDeviceSupportsTouch = m_webViewImpl->page()->settings().deviceSupportsTouch();
        m_originalMaxTouchPoints = m_webViewImpl->page()->settings().maxTouchPoints();
    }
    RuntimeEnabledFeatures::setTouchEnabled(enabled ? true : m_originalTouchEnabled);
    if (!m_originalDeviceSupportsTouch) {
        m_webViewImpl->page()->settings().setDeviceSupportsMouse(enabled ? false : m_originalDeviceSupportsMouse);
        m_webViewImpl->page()->settings().setDeviceSupportsTouch(enabled ? true : m_originalDeviceSupportsTouch);
        // Currently emulation does not provide multiple touch points.
        m_webViewImpl->page()->settings().setMaxTouchPoints(enabled ? 1 : m_originalMaxTouchPoints);
    }
    m_touchEventEmulationEnabled = enabled;
    m_webViewImpl->mainFrameImpl()->frameView()->layout();
}

void DevToolsEmulator::setScriptExecutionDisabled(bool scriptExecutionDisabled)
{
    m_scriptExecutionDisabled = scriptExecutionDisabled;
    m_webViewImpl->page()->settings().setScriptEnabled(m_scriptExecutionDisabled ? false : m_embedderScriptEnabled);
}

bool DevToolsEmulator::handleInputEvent(const WebInputEvent& inputEvent)
{
    Page* page = m_webViewImpl->page();
    if (!page)
        return false;

    // FIXME: This workaround is required for touch emulation on Mac, where
    // compositor-side pinch handling is not enabled. See http://crbug.com/138003.
    bool isPinch = inputEvent.type == WebInputEvent::GesturePinchBegin || inputEvent.type == WebInputEvent::GesturePinchUpdate || inputEvent.type == WebInputEvent::GesturePinchEnd;
    if (isPinch && m_touchEventEmulationEnabled) {
        FrameView* frameView = page->deprecatedLocalMainFrame()->view();
        PlatformGestureEventBuilder gestureEvent(frameView, static_cast<const WebGestureEvent&>(inputEvent));
        float pageScaleFactor = page->pageScaleFactor();
        if (gestureEvent.type() == PlatformEvent::GesturePinchBegin) {
            m_lastPinchAnchorCss = adoptPtr(new IntPoint(frameView->scrollPosition() + gestureEvent.position()));
            m_lastPinchAnchorDip = adoptPtr(new IntPoint(gestureEvent.position()));
            m_lastPinchAnchorDip->scale(pageScaleFactor, pageScaleFactor);
        }
        if (gestureEvent.type() == PlatformEvent::GesturePinchUpdate && m_lastPinchAnchorCss) {
            float newPageScaleFactor = pageScaleFactor * gestureEvent.scale();
            IntPoint anchorCss(*m_lastPinchAnchorDip.get());
            anchorCss.scale(1.f / newPageScaleFactor, 1.f / newPageScaleFactor);
            m_webViewImpl->setPageScaleFactor(newPageScaleFactor);
            m_webViewImpl->mainFrame()->setScrollOffset(toIntSize(*m_lastPinchAnchorCss.get() - toIntSize(anchorCss)));
        }
        if (gestureEvent.type() == PlatformEvent::GesturePinchEnd) {
            m_lastPinchAnchorCss.clear();
            m_lastPinchAnchorDip.clear();
        }
        return true;
    }

    return false;
}

} // namespace blink