environment.cpp Example File

  /****************************************************************************
  **
  ** Copyright (C) 2015 The Qt Company Ltd.
  ** Contact: http://www.qt.io/licensing/
  **
  ** This file is part of the examples of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:BSD$
  ** You may use this file under the terms of the BSD license as follows:
  **
  ** "Redistribution and use in source and binary forms, with or without
  ** modification, are permitted provided that the following conditions are
  ** met:
  **   * Redistributions of source code must retain the above copyright
  **     notice, this list of conditions and the following disclaimer.
  **   * Redistributions in binary form must reproduce the above copyright
  **     notice, this list of conditions and the following disclaimer in
  **     the documentation and/or other materials provided with the
  **     distribution.
  **   * Neither the name of The Qt Company Ltd nor the names of its
  **     contributors may be used to endorse or promote products derived
  **     from this software without specific prior written permission.
  **
  **
  ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
  **
  ** $QT_END_LICENSE$
  **
  ****************************************************************************/

  #include "environment.h"
  #include "qcontext2dcanvas.h"
  #include "context2d.h"
  #include <QScriptValueIterator>
  #include <QDateTime>

  struct FakeDomEvent
  {
      enum KeyCodes  {
          DOM_VK_UNDEFINED            = 0x0,
          DOM_VK_RIGHT_ALT            = 0x12,
          DOM_VK_LEFT_ALT             = 0x12,
          DOM_VK_LEFT_CONTROL         = 0x11,
          DOM_VK_RIGHT_CONTROL        = 0x11,
          DOM_VK_LEFT_SHIFT           = 0x10,
          DOM_VK_RIGHT_SHIFT          = 0x10,
          DOM_VK_META                 = 0x9D,
          DOM_VK_BACK_SPACE           = 0x08,
          DOM_VK_CAPS_LOCK            = 0x14,
          DOM_VK_DELETE               = 0x7F,
          DOM_VK_END                  = 0x23,
          DOM_VK_ENTER                = 0x0D,
          DOM_VK_ESCAPE               = 0x1B,
          DOM_VK_HOME                 = 0x24,
          DOM_VK_NUM_LOCK             = 0x90,
          DOM_VK_PAUSE                = 0x13,
          DOM_VK_PRINTSCREEN          = 0x9A,
          DOM_VK_SCROLL_LOCK          = 0x91,
          DOM_VK_SPACE                = 0x20,
          DOM_VK_TAB                  = 0x09,
          DOM_VK_LEFT                 = 0x25,
          DOM_VK_RIGHT                = 0x27,
          DOM_VK_UP                   = 0x26,
          DOM_VK_DOWN                 = 0x28,
          DOM_VK_PAGE_DOWN            = 0x22,
          DOM_VK_PAGE_UP              = 0x21,
          DOM_VK_F1                   = 0x70,
          DOM_VK_F2                   = 0x71,
          DOM_VK_F3                   = 0x72,
          DOM_VK_F4                   = 0x73,
          DOM_VK_F5                   = 0x74,
          DOM_VK_F6                   = 0x75,
          DOM_VK_F7                   = 0x76,
          DOM_VK_F8                   = 0x77,
          DOM_VK_F9                   = 0x78,
          DOM_VK_F10                  = 0x79,
          DOM_VK_F11                  = 0x7A,
          DOM_VK_F12                  = 0x7B,
          DOM_VK_F13                  = 0xF000,
          DOM_VK_F14                  = 0xF001,
          DOM_VK_F15                  = 0xF002,
          DOM_VK_F16                  = 0xF003,
          DOM_VK_F17                  = 0xF004,
          DOM_VK_F18                  = 0xF005,
          DOM_VK_F19                  = 0xF006,
          DOM_VK_F20                  = 0xF007,
          DOM_VK_F21                  = 0xF008,
          DOM_VK_F22                  = 0xF009,
          DOM_VK_F23                  = 0xF00A,
          DOM_VK_F24                  = 0xF00B
      };

      static int qtToDomKey(int keyCode);
  };

  int FakeDomEvent::qtToDomKey(int keyCode)
  {
      switch (keyCode) {
      case Qt::Key_Backspace:
          return  DOM_VK_BACK_SPACE;
      case Qt::Key_Enter:
          return  DOM_VK_ENTER;
      case Qt::Key_Return:
          return  DOM_VK_ENTER;
      case Qt::Key_NumLock:
          return  DOM_VK_NUM_LOCK;
      case Qt::Key_Alt:
          return  DOM_VK_RIGHT_ALT;
      case Qt::Key_Control:
          return  DOM_VK_LEFT_CONTROL;
      case Qt::Key_Shift:
          return  DOM_VK_LEFT_SHIFT;
      case Qt::Key_Meta:
          return  DOM_VK_META;
      case Qt::Key_CapsLock:
          return  DOM_VK_CAPS_LOCK;
      case Qt::Key_Delete:
          return  DOM_VK_DELETE;
      case Qt::Key_End:
          return  DOM_VK_END;
      case Qt::Key_Escape:
          return  DOM_VK_ESCAPE;
      case Qt::Key_Home:
          return  DOM_VK_HOME;
      case Qt::Key_Pause:
          return  DOM_VK_PAUSE;
      case Qt::Key_Print:
          return  DOM_VK_PRINTSCREEN;
      case Qt::Key_ScrollLock:
          return  DOM_VK_SCROLL_LOCK;
      case Qt::Key_Left:
          return  DOM_VK_LEFT;
      case Qt::Key_Right:
          return  DOM_VK_RIGHT;
      case Qt::Key_Up:
          return  DOM_VK_UP;
      case Qt::Key_Down:
          return  DOM_VK_DOWN;
      case Qt::Key_PageDown:
          return  DOM_VK_PAGE_DOWN;
      case Qt::Key_PageUp:
          return  DOM_VK_PAGE_UP;
      case Qt::Key_F1:
          return  DOM_VK_F1;
      case Qt::Key_F2:
          return  DOM_VK_F2;
      case Qt::Key_F3:
          return  DOM_VK_F3;
      case Qt::Key_F4:
          return  DOM_VK_F4;
      case Qt::Key_F5:
          return  DOM_VK_F5;
      case Qt::Key_F6:
          return  DOM_VK_F6;
      case Qt::Key_F7:
          return  DOM_VK_F7;
      case Qt::Key_F8:
          return  DOM_VK_F8;
      case Qt::Key_F9:
          return  DOM_VK_F9;
      case Qt::Key_F10:
          return  DOM_VK_F10;
      case Qt::Key_F11:
          return  DOM_VK_F11;
      case Qt::Key_F12:
          return  DOM_VK_F12;
      case Qt::Key_F13:
          return  DOM_VK_F13;
      case Qt::Key_F14:
          return  DOM_VK_F14;
      case Qt::Key_F15:
          return  DOM_VK_F15;
      case Qt::Key_F16:
          return  DOM_VK_F16;
      case Qt::Key_F17:
          return  DOM_VK_F17;
      case Qt::Key_F18:
          return  DOM_VK_F18;
      case Qt::Key_F19:
          return  DOM_VK_F19;
      case Qt::Key_F20:
          return  DOM_VK_F20;
      case Qt::Key_F21:
          return  DOM_VK_F21;
      case Qt::Key_F22:
          return  DOM_VK_F22;
      case Qt::Key_F23:
          return  DOM_VK_F23;
      case Qt::Key_F24:
          return  DOM_VK_F24;
      }
      return keyCode;
  }

  Environment::Environment(QObject *parent)
      : QObject(parent)
  {
      m_engine = new QScriptEngine(this);

      m_document = m_engine->newQObject(
          new Document(this), QScriptEngine::QtOwnership,
          QScriptEngine::ExcludeSuperClassContents);

      CanvasGradientPrototype::setup(m_engine);

      m_originalGlobalObject = m_engine->globalObject();
      reset();
  }

  Environment::~Environment()
  {
  }

  QScriptEngine *Environment::engine() const
  {
      return m_engine;
  }

  QScriptValue Environment::document() const
  {
      return m_document;
  }

  int Environment::setTimeout(const QScriptValue &expression, int delay)
  {
      if (expression.isString() || expression.isFunction()) {
          int timerId = startTimer(delay);
          m_timeoutHash.insert(timerId, expression);
          return timerId;
      }
      return -1;
  }

  void Environment::clearTimeout(int timerId)
  {
      killTimer(timerId);
      m_timeoutHash.remove(timerId);
  }

  int Environment::setInterval(const QScriptValue &expression, int delay)
  {
      if (expression.isString() || expression.isFunction()) {
          int timerId = startTimer(delay);
          m_intervalHash.insert(timerId, expression);
          return timerId;
      }
      return -1;
  }

  void Environment::clearInterval(int timerId)
  {
      killTimer(timerId);
      m_intervalHash.remove(timerId);
  }

  void Environment::timerEvent(QTimerEvent *event)
  {
      int id = event->timerId();
      QScriptValue expression = m_intervalHash.value(id);
      if (!expression.isValid()) {
          expression = m_timeoutHash.value(id);
          if (expression.isValid())
              killTimer(id);
      }
      if (expression.isString()) {
          evaluate(expression.toString());
      } else if (expression.isFunction()) {
          expression.call();
      }
      maybeEmitScriptError();
  }

  void Environment::addCanvas(QContext2DCanvas *canvas)
  {
      m_canvases.append(canvas);
  }

  QContext2DCanvas *Environment::canvasByName(const QString &name) const
  {
      for (int i = 0; i < m_canvases.size(); ++i) {
          QContext2DCanvas *canvas = m_canvases.at(i);
          if (canvas->objectName() == name)
              return canvas;
      }
      return 0;
  }

  QList<QContext2DCanvas*> Environment::canvases() const
  {
      return m_canvases;
  }

  void Environment::reset()
  {
      if (m_engine->isEvaluating())
          m_engine->abortEvaluation();

      {
          QHash<int, QScriptValue>::const_iterator it;
          for (it = m_intervalHash.constBegin(); it != m_intervalHash.constEnd(); ++it)
              killTimer(it.key());
          m_intervalHash.clear();
          for (it = m_timeoutHash.constBegin(); it != m_timeoutHash.constEnd(); ++it)
              killTimer(it.key());
          m_timeoutHash.clear();
      }

      for (int i = 0; i < m_canvases.size(); ++i)
          m_canvases.at(i)->reset();

      QScriptValue self = m_engine->newQObject(
          this, QScriptEngine::QtOwnership,
          QScriptEngine::ExcludeSuperClassContents);

      {
          QScriptValueIterator it(m_originalGlobalObject);
          while (it.hasNext()) {
              it.next();
              self.setProperty(it.scriptName(), it.value(), it.flags());
          }
      }

      self.setProperty("self", self);
      self.setProperty("window", self);

      QScriptValue navigator = m_engine->newObject();
      navigator.setProperty("appCodeName", "context2d");
      navigator.setProperty("appMinorVersion", 1);
      navigator.setProperty("appVersion", 1);
      navigator.setProperty("browserLanguage", "en_US");
      navigator.setProperty("cookieEnabled", false);
      navigator.setProperty("cpuClass", "i686");
      navigator.setProperty("onLine", false);
      navigator.setProperty("platform", "bogus OS");
      navigator.setProperty("systemLanguage", "en_US");
      navigator.setProperty("userAgent", "Context2D/1.1");
      navigator.setProperty("userLanguage", "en_US");
      self.setProperty("navigator", navigator);

      m_engine->setGlobalObject(self);

      m_engine->collectGarbage();
  }

  QScriptValue Environment::evaluate(const QString &code, const QString &fileName)
  {
      return m_engine->evaluate(code, fileName);
  }

  bool Environment::hasIntervalTimers() const
  {
      return !m_intervalHash.isEmpty();
  }

  // This is used by the Context2D Qt Script benchmark.
  void Environment::triggerTimers()
  {
      for (int x = 0; x < 2; ++x) {
          QList<int> timerIds = x ? m_intervalHash.keys() : m_timeoutHash.keys();
          for (int i = 0; i < timerIds.size(); ++i) {
              QTimerEvent fakeEvent(timerIds.at(i));
              timerEvent(&fakeEvent);
          }
      }
  }

  QScriptValue Environment::toWrapper(QObject *object)
  {
      return m_engine->newQObject(object, QScriptEngine::QtOwnership,
                                  QScriptEngine::PreferExistingWrapperObject
                                  | QScriptEngine::ExcludeSuperClassContents);
  }

  void Environment::handleEvent(QContext2DCanvas *canvas, QMouseEvent *e)
  {
      QString type;
      switch (e->type()) {
      case QEvent::MouseButtonPress:
          type = "mousedown"; break;
      case QEvent::MouseButtonRelease:
          type = "mouseup"; break;
      case QEvent::MouseMove:
          type = "mousemove"; break;
      default: break;
      }
      if (type.isEmpty())
          return;

      QScriptValue handlerObject;
      QScriptValue handler = eventHandler(canvas, type, &handlerObject);
      if (!handler.isFunction())
          return;

      QScriptValue scriptEvent = newFakeDomEvent(type, toWrapper(canvas));
      // MouseEvent
      scriptEvent.setProperty("screenX", e->globalX(), QScriptValue::ReadOnly);
      scriptEvent.setProperty("screenY", e->globalY(), QScriptValue::ReadOnly);
      scriptEvent.setProperty("clientX", e->x(), QScriptValue::ReadOnly);
      scriptEvent.setProperty("clientY", e->y(), QScriptValue::ReadOnly);
      scriptEvent.setProperty("layerX", e->x(), QScriptValue::ReadOnly);
      scriptEvent.setProperty("layerY", e->y(), QScriptValue::ReadOnly);
      scriptEvent.setProperty("pageX", e->x(), QScriptValue::ReadOnly);
      scriptEvent.setProperty("pageY", e->y(), QScriptValue::ReadOnly);
      scriptEvent.setProperty("altKey", (e->modifiers() & Qt::AltModifier) != 0,
                              QScriptValue::ReadOnly);
      scriptEvent.setProperty("ctrlKey", (e->modifiers() & Qt::ControlModifier) != 0,
                              QScriptValue::ReadOnly);
      scriptEvent.setProperty("metaKey", (e->modifiers() & Qt::MetaModifier) != 0,
                              QScriptValue::ReadOnly);
      scriptEvent.setProperty("shiftKey", (e->modifiers() & Qt::ShiftModifier) != 0,
                              QScriptValue::ReadOnly);
      int button = 0;
      if (e->button() == Qt::RightButton)
          button = 2;
      else if (e->button() == Qt::MidButton)
          button = 1;
      scriptEvent.setProperty("button", button);
      scriptEvent.setProperty("relatedTarget", m_engine->nullValue(),
                              QScriptValue::ReadOnly);
      handler.call(handlerObject, QScriptValueList() << scriptEvent);
      maybeEmitScriptError();
  }

  void Environment::handleEvent(QContext2DCanvas *canvas, QKeyEvent *e)
  {
      QString type;
      switch (e->type()) {
      case QEvent::KeyPress:
          type = "keydown"; break;
      case QEvent::KeyRelease:
          type = "keyup"; break;
      default: break;
      }
      if (type.isEmpty())
          return;

      QScriptValue handlerObject;
      QScriptValue handler = eventHandler(canvas, type, &handlerObject);
      if (!handler.isFunction())
          return;

      QScriptValue scriptEvent = newFakeDomEvent(type, toWrapper(canvas));
      // KeyEvent
      scriptEvent.setProperty("isChar", !e->text().isEmpty());
      scriptEvent.setProperty("charCode", e->text());
      scriptEvent.setProperty("keyCode", FakeDomEvent::qtToDomKey(e->key()));
      scriptEvent.setProperty("which", e->key());

      handler.call(handlerObject, QScriptValueList() << scriptEvent);
      maybeEmitScriptError();
  }

  QScriptValue Environment::eventHandler(QContext2DCanvas *canvas, const QString &type,
                                         QScriptValue *who)
  {
      QString handlerName = "on" + type;
      QScriptValue obj = toWrapper(canvas);
      QScriptValue handler = obj.property(handlerName);
      if (!handler.isValid()) {
          obj = m_document;
          handler = obj.property(handlerName);
      }
      if (who && handler.isFunction())
          *who = obj;
      return handler;
  }

  QScriptValue Environment::newFakeDomEvent(const QString &type, const QScriptValue &target)
  {
      QScriptValue e = m_engine->newObject();
      // Event
      e.setProperty("type", type, QScriptValue::ReadOnly);
      e.setProperty("bubbles", true, QScriptValue::ReadOnly);
      e.setProperty("cancelable", false, QScriptValue::ReadOnly);
      e.setProperty("target", target, QScriptValue::ReadOnly);
      e.setProperty("currentTarget", target, QScriptValue::ReadOnly);
      e.setProperty("eventPhase", 3); // bubbling
      e.setProperty("timeStamp", QDateTime::currentDateTime().toTime_t());
      // UIEvent
      e.setProperty("detail", 0, QScriptValue::ReadOnly);
      e.setProperty("view", m_engine->globalObject(), QScriptValue::ReadOnly);
      return e;
  }

  void Environment::maybeEmitScriptError()
  {
      if (m_engine->hasUncaughtException())
          emit scriptError(m_engine->uncaughtException());
  }

  Document::Document(Environment *env)
      : QObject(env)
  {
  }

  Document::~Document()
  {
  }

  QScriptValue Document::getElementById(const QString &id) const
  {
      Environment *env = qobject_cast<Environment*>(parent());
      QContext2DCanvas *canvas = env->canvasByName(id);
      if (!canvas)
          return QScriptValue();
      return env->toWrapper(canvas);
  }

  QScriptValue Document::getElementsByTagName(const QString &name) const
  {
      if (name != "canvas")
          return QScriptValue();
      Environment *env = qobject_cast<Environment*>(parent());
      QList<QContext2DCanvas*> list = env->canvases();
      QScriptValue result = env->engine()->newArray(list.size());
      for (int i = 0; i < list.size(); ++i)
          result.setProperty(i, env->toWrapper(list.at(i)));
      return result;
  }

  void Document::addEventListener(const QString &type, const QScriptValue &listener,
                                  bool useCapture)
  {
      Q_UNUSED(useCapture);
      if (listener.isFunction()) {
          Environment *env = qobject_cast<Environment*>(parent());
          QScriptValue self = env->toWrapper(this);
          self.setProperty("on" + type, listener);
      }
  }

  QColor colorFromString(const QString &name);

  CanvasGradientPrototype::CanvasGradientPrototype(QObject *parent)
      : QObject(parent)
  {
  }

  void CanvasGradientPrototype::addColorStop(qreal offset, const QString &color)
  {
      CanvasGradient *self = qscriptvalue_cast<CanvasGradient*>(thisObject());
      if (!self || (self->value.type() == QGradient::NoGradient))
          return;
      self->value.setColorAt(offset, colorFromString(color));
  }

  void CanvasGradientPrototype::setup(QScriptEngine *engine)
  {
      CanvasGradientPrototype *proto = new CanvasGradientPrototype();
      engine->setDefaultPrototype(qMetaTypeId<CanvasGradient>(),
          engine->newQObject(proto, QScriptEngine::ScriptOwnership,
                             QScriptEngine::ExcludeSuperClassContents));
  }