/**************************************************************************
**
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** Contact: http://www.qt-project.org/legal
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** This file is part of the Qt Installer Framework.
**
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**************************************************************************/
#include "scriptengine.h"

#include "messageboxhandler.h"
#include "errors.h"
#include "scriptengine_p.h"
#include "systeminfo.h"

#include <QMetaEnum>
#include <QQmlEngine>
#include <QUuid>
#include <QWizard>

namespace QInstaller {

/*!
    \class QInstaller::ScriptEngine
    \inmodule QtInstallerFramework
    \brief The ScriptEngine class is used to prepare and run the component scripts.
*/

/*!
    \qmltype console
    \inqmlmodule scripting
    \brief Provides methods for logging and debugging.
*/

/*!
    \qmlmethod void console::log(string value)
*/

/*!
    \qmltype QFileDialog
    \inqmlmodule scripting
*/

/*!
    \qmlmethod string QFileDialog::getExistingDirectory(string caption, string dir)
*/

/*!
    \qmlmethod string QFileDialog::getOpenFileName(string caption, string dir, string filter)
*/

/*!
    \qmltype print
    \inqmlmodule scripting
*/

/*!
    \qmltype buttons
    \inqmlmodule scripting

    \brief Provides buttons that can be used on installer pages.

    You can use a set of standard buttons and some custom buttons on the
    installer pages. For more information about the buttons used by default on
    each installer page, see \l {Controller Scripting}.
*/

/*!
    \qmlproperty enumeration buttons::QWizard

    Specifies the buttons on an installer page.

    \value  buttons.BackButton
            The \uicontrol Back button (\uicontrol {Go Back} on OS X.)
    \value  buttons.NextButton
            The \uicontrol Next button (\uicontrol Continue on OS X.)
    \value  buttons.CommitButton
            The \uicontrol Commit button.
    \value  buttons.FinishButton
            The \uicontrol Finish button (\uicontrol Done on OS X.)
    \value  buttons.CancelButton
            The \uicontrol Cancel button.
    \value  buttons.HelpButton
            The \uicontrol Help button.
    \value  buttons.CustomButton1
            A custom button.
    \value  buttons.CustomButton2
            A custom button.
    \value  buttons.CustomButton3
            A custom button.
*/

/*!
    \qmltype QDesktopServices
    \inqmlmodule scripting
*/

/*!
    \qmlproperty enumeration QDesktopServices::QStandardPaths

    \list
        \li DesktopServices.DesktopLocation
        \li DesktopServices.DocumentsLocation
        \li DesktopServices.FontsLocation
        \li DesktopServices.ApplicationsLocation
        \li DesktopServices.MusicLocation
        \li DesktopServices.MoviesLocation
        \li DesktopServices.PicturesLocation
        \li DesktopServices.TempLocation
        \li DesktopServices.HomeLocation
        \li DesktopServices.DataLocation
        \li DesktopServices.CacheLocation
        \li DesktopServices.GenericDataLocation
        \li DesktopServices.RuntimeLocation
        \li DesktopServices.ConfigLocation
        \li DesktopServices.DownloadLocation
        \li DesktopServices.GenericCacheLocation
        \li DesktopServices.GenericConfigLocation
    \endlist
*/

/*!
    \qmlmethod boolean QDesktopServices::openUrl(string url)
*/

/*!
    \qmlmethod string QDesktopServices::displayName(int location)
*/

/*!
    \qmlmethod string QDesktopServices::storageLocation(int location)
*/

/*!
    \qmltype QInstaller
    \inqmlmodule scripting

    \brief Provides access to the installer status and pages from Qt Script.
*/

/*!
   \qmlproperty enumeration QInstaller::WizardPage

    The installer has various pre-defined pages that can be used to for example insert pages
    in a certain place:
    \list
        \li QInstaller.Introduction
        \li QInstaller.TargetDirectory
        \li QInstaller.ComponentSelection
        \li QInstaller.LicenseCheck
        \li QInstaller.StartMenuSelection
        \li QInstaller.ReadyForInstallation
        \li QInstaller.PerformInstallation
        \li QInstaller.InstallationFinished
        \li QInstaller.End
    \endlist
*/


/*!
    \qmlproperty enumeration QInstaller::status

    Status of the installer.

    Possible values are:
    \list
        \li QInstaller.Success (deprecated: QInstaller.InstallerSucceeded)
        \li QInstaller.Failure (deprecated: QInstaller.InstallerFailed)
        \li QInstaller.Running (deprecated: QInstaller.InstallerFailed)
        \li QInstaller.Canceled (deprecated: QInstaller.CanceledByUser)
        \li QInstaller.Unfinished (deprecated: QInstaller.InstallerUnfinished)
        \li QInstaller.ForceUpdate
    \endlist
*/

/*!
    \qmltype gui
    \inqmlmodule scripting
*/

/*!
    \qmlsignal gui::interrupted()
*/

/*!
    \qmlsignal gui::languageChanged()
*/

/*!
    \qmlsignal gui::finishButtonClicked()
*/

/*!
    \qmlsignal gui::gotRestarted()
*/

/*!
    \qmlsignal gui::settingsButtonClicked();
*/

GuiProxy::GuiProxy(ScriptEngine *engine, QObject *parent) :
    QObject(parent),
    m_engine(engine),
    m_gui(0)
{
}

void GuiProxy::setPackageManagerGui(PackageManagerGui *gui)
{
    if (m_gui) {
        disconnect(m_gui, &PackageManagerGui::interrupted, this, &GuiProxy::interrupted);
        disconnect(m_gui, &PackageManagerGui::languageChanged, this, &GuiProxy::languageChanged);
        disconnect(m_gui, &PackageManagerGui::finishButtonClicked, this, &GuiProxy::finishButtonClicked);
        disconnect(m_gui, &PackageManagerGui::gotRestarted, this, &GuiProxy::gotRestarted);
        disconnect(m_gui, &PackageManagerGui::settingsButtonClicked, this, &GuiProxy::settingsButtonClicked);
    }

    m_gui = gui;

    if (m_gui) {
        connect(m_gui, &PackageManagerGui::interrupted, this, &GuiProxy::interrupted);
        connect(m_gui, &PackageManagerGui::languageChanged, this, &GuiProxy::languageChanged);
        connect(m_gui, &PackageManagerGui::finishButtonClicked, this, &GuiProxy::finishButtonClicked);
        connect(m_gui, &PackageManagerGui::gotRestarted, this, &GuiProxy::gotRestarted);
        connect(m_gui, &PackageManagerGui::settingsButtonClicked, this, &GuiProxy::settingsButtonClicked);
    }
}

/*!
    \qmlmethod object gui::pageById(int id)
*/
QJSValue GuiProxy::pageById(int id) const
{
    if (!m_gui)
        return QJSValue();
    return m_engine->newQObject(m_gui->pageById(id));
}

/*!
    \qmlmethod object gui::pageByObjectName(string name)
*/
QJSValue GuiProxy::pageByObjectName(const QString &name) const
{
    if (!m_gui)
        return QJSValue();
    return m_engine->newQObject(m_gui->pageByObjectName(name));
}

/*!
    \qmlmethod object gui::currentPageWidget()
*/
QJSValue GuiProxy::currentPageWidget() const
{
    if (!m_gui)
        return QJSValue();
    return m_engine->newQObject(m_gui->currentPageWidget());
}

/*!
    \qmlmethod object gui::pageWidgetByObjectName(string name)
*/
QJSValue GuiProxy::pageWidgetByObjectName(const QString &name) const
{
    if (!m_gui)
        return QJSValue();
    return m_engine->newQObject(m_gui->pageWidgetByObjectName(name));
}

/*!
    \qmlmethod string gui::defaultButtonText(int wizardButton)
*/
QString GuiProxy::defaultButtonText(int wizardButton) const
{
    if (!m_gui)
        return QString();
    return m_gui->defaultButtonText(wizardButton);
}

/*!
    \qmlmethod void gui::clickButton(int wizardButton, int delayInMs)
*/
void GuiProxy::clickButton(int wizardButton, int delayInMs)
{
    if (m_gui)
        m_gui->clickButton(wizardButton, delayInMs);
}

/*!
    \qmlmethod boolean gui::isButtonEnabled(int wizardButton)
*/
bool GuiProxy::isButtonEnabled(int wizardButton)
{
    if (!m_gui)
        return false;
    return m_gui->isButtonEnabled(wizardButton);
}

/*!
    \qmlmethod void gui::showSettingsButton(boolean show)
*/
void GuiProxy::showSettingsButton(bool show)
{
    if (m_gui)
        m_gui->showSettingsButton(show);
}

/*!
    \qmlmethod void gui::setSettingsButtonEnabled(boolean enable)
*/
void GuiProxy::setSettingsButtonEnabled(bool enable)
{
    if (m_gui)
        m_gui->setSettingsButtonEnabled(enable);
}

/*!
    \qmlmethod object gui::findChild(object parent, string objectName)

    Returns the first descendant of \a parent that has \a objectName as name.

    \sa QObject::findChild
*/
QJSValue GuiProxy::findChild(QObject *parent, const QString &objectName)
{
    return m_engine->newQObject(parent->findChild<QObject*>(objectName));
}

/*!
    \qmlmethod object[] gui::findChildren(object parent, string objectName)

    Returns all descendants of \a parent that have \a objectName as name.

    \sa QObject::findChildren
*/
QList<QJSValue> GuiProxy::findChildren(QObject *parent, const QString &objectName)
{
    QList<QJSValue> children;
    foreach (QObject *child, parent->findChildren<QObject*>(objectName))
        children.append(m_engine->newQObject(child));
    return children;
}

/*!
    \qmlmethod void gui::cancelButtonClicked()
*/
void GuiProxy::cancelButtonClicked()
{
    if (m_gui)
        m_gui->cancelButtonClicked();
}

/*!
    \qmlmethod void gui::reject()
*/
void GuiProxy::reject()
{
    if (m_gui)
        m_gui->reject();
}

/*!
    \qmlmethod void gui::rejectWithoutPrompt()
*/
void GuiProxy::rejectWithoutPrompt()
{
    if (m_gui)
        m_gui->rejectWithoutPrompt();
}

/*!
    \qmlmethod void gui::showFinishedPage()
*/
void GuiProxy::showFinishedPage()
{
    if (m_gui)
        m_gui->showFinishedPage();
}

/*!
    \qmlmethod void gui::setModified(boolean value)
*/
void GuiProxy::setModified(bool value)
{
    if (m_gui)
        m_gui->setModified(value);
}


/*!
    Constructs a script engine with \a core as parent.
*/
ScriptEngine::ScriptEngine(PackageManagerCore *core) :
    QObject(core),
    m_guiProxy(new GuiProxy(this, this))
{
    QJSValue global = m_engine.globalObject();
    global.setProperty(QLatin1String("console"), m_engine.newQObject(new ConsoleProxy));
    global.setProperty(QLatin1String("QFileDialog"), m_engine.newQObject(new QFileDialogProxy));
    const QJSValue proxy = m_engine.newQObject(new InstallerProxy(&m_engine, core));
    global.setProperty(QLatin1String("InstallerProxy"), proxy);
    global.setProperty(QLatin1String("print"), m_engine.newQObject(new ConsoleProxy)
        .property(QLatin1String("log")));
#if QT_VERSION < 0x050400
    global.setProperty(QLatin1String("qsTr"), m_engine.newQObject(new QCoreApplicationProxy)
        .property(QStringLiteral("qsTr")));
#else
    m_engine.installTranslatorFunctions();
#endif
    global.setProperty(QLatin1String("systemInfo"), m_engine.newQObject(new SystemInfo));

    global.setProperty(QLatin1String("QInstaller"), generateQInstallerObject());
    global.setProperty(QLatin1String("buttons"), generateWizardButtonsObject());
    global.setProperty(QLatin1String("QMessageBox"), generateMessageBoxObject());
    global.setProperty(QLatin1String("QDesktopServices"), generateDesktopServicesObject());

    if (core) {
        setGuiQObject(core->guiObject());
        QQmlEngine::setObjectOwnership(core, QQmlEngine::CppOwnership);
        global.setProperty(QLatin1String("installer"), m_engine.newQObject(core));
        connect(core, SIGNAL(guiObjectChanged(QObject*)), this, SLOT(setGuiQObject(QObject*)));

        const QList<Component*> all = core->components(PackageManagerCore::ComponentType::All);
        QJSValue scriptComponentsObject = m_engine.newArray(all.count());
        for (int i = 0; i < all.count(); ++i) {
            Component *const component = all.at(i);
            QQmlEngine::setObjectOwnership(component, QQmlEngine::CppOwnership);
            scriptComponentsObject.setProperty(i, newQObject(component));
        }
        global.property(QLatin1String("installer")).setProperty(QLatin1String("components"),
            scriptComponentsObject);
    } else {
        global.setProperty(QLatin1String("installer"), m_engine.newQObject(new QObject));
    }
    global.setProperty(QLatin1String("gui"), m_engine.newQObject(m_guiProxy));

    global.property(QLatin1String("installer")).setProperty(QLatin1String("componentByName"),
        proxy.property(QLatin1String("componentByName")));
}

/*!
    Creates a JavaScript object that wraps the given QObject \a object.

    Signals and slots, properties and children of \a object are
    available as properties of the created QJSValue. In addition some helper methods and properties
    are added:

    findChild(), findChildren() recursively search for child objects with the given object name.

    Direct child objects are made accessible as properties under their respective object names.
 */
QJSValue ScriptEngine::newQObject(QObject *object)
{
    QJSValue jsValue = m_engine.newQObject(object);
    QQmlEngine::setObjectOwnership(object, QQmlEngine::CppOwnership);

    // add findChild(), findChildren() methods known from QtScript
    QJSValue findChild = m_engine.evaluate(
                QLatin1String("(function() { return gui.findChild(this, arguments[0]); })"));
    QJSValue findChildren = m_engine.evaluate(
                QLatin1String("(function() { return gui.findChildren(this, arguments[0]); })"));
    jsValue.setProperty(QLatin1String("findChild"), findChild);
    jsValue.setProperty(QLatin1String("findChildren"), findChildren);

    // add all named children as properties
    foreach (QObject *const child, object->children()) {
        if (child->objectName().isEmpty())
            continue;
        jsValue.setProperty(child->objectName(), m_engine.newQObject(child));
        newQObject(child);
    }

    return jsValue;
}

QJSValue ScriptEngine::evaluate(const QString &program, const QString &fileName, int lineNumber)
{
    return m_engine.evaluate(program, fileName, lineNumber);
}

/*!
    Registers QObject \a object in the engine, and makes it globally accessible under its object name.
 */
void ScriptEngine::addToGlobalObject(QObject *object)
{
    if (!object || object->objectName().isEmpty())
        return;

    QJSValue value = newQObject(object);
    globalObject().setProperty(object->objectName(), value);
}

/*!
    Removes the \a object name from the global object.
 */
void ScriptEngine::removeFromGlobalObject(QObject *object)
{
    globalObject().deleteProperty(object->objectName());
}

/*!
    Loads a script into the given \a context at \a fileName inside the ScriptEngine.

    The installer and all its components as well as other useful stuff are being exported into the
    script. Read \link componentscripting Component Scripting \endlink for details.
    Throws Error when either the script at \a fileName could not be opened, or the QScriptEngine
    couldn't evaluate the script.
*/
QJSValue ScriptEngine::loadInContext(const QString &context, const QString &fileName,
    const QString &scriptInjection)
{
    QFile file(fileName);
    if (!file.open(QIODevice::ReadOnly)) {
        throw Error(tr("Could not open the requested script file at %1: %2.")
            .arg(fileName, file.errorString()));
    }

    // Create a closure. Put the content in the first line to keep line number order in case of an
    // exception. Script content will be added as the last argument to the command to prevent wrong
    // replacements of %1, %2 or %3 inside the javascript code.
    const QString scriptContent = QLatin1String("(function() {")
        + scriptInjection + QString::fromUtf8(file.readAll())
        + QString::fromLatin1(";"
        "    if (typeof %1 != \"undefined\")"
        "        return new %1;"
        "    else"
        "        throw \"Missing Component constructor. Please check your script.\";"
        "})();").arg(context);
    QJSValue scriptContext = evaluate(scriptContent, fileName);
    scriptContext.setProperty(QLatin1String("Uuid"), QUuid::createUuid().toString());
    if (scriptContext.isError()) {
        throw Error(tr("Exception while loading the component script '%1'. (%2)").arg(
            QFileInfo(file).absoluteFilePath(), scriptContext.toString().isEmpty() ?
            QString::fromLatin1("Unknown error.") : scriptContext.toString()));
    }
    return scriptContext;
}

/*!
    Tries to call the method with \a name within the script and returns the result. If the method
    doesn't exist or is not callable, an undefined result is returned. If the call to the method
    succeeds and the return value is still undefined, a null value will be returned instead.
    If the method call has an exception, its string representation is thrown as an Error exception.

    \note The method is not called, if the current script context is the same method, to avoid
    infinite recursion.
*/
QJSValue ScriptEngine::callScriptMethod(const QJSValue &scriptContext, const QString &methodName,
    const QJSValueList &arguments)
{
    // don't allow a recursion
    const QString key = scriptContext.property(QLatin1String("Uuid")).toString();
    QStringList stack = m_callstack.value(key);
    if (m_callstack.contains(key) && stack.value(stack.size() - 1).startsWith(methodName))
        return QJSValue(QJSValue::UndefinedValue);

    stack.append(methodName);
    m_callstack.insert(key, stack);

    QJSValue method = scriptContext.property(methodName);
    if (!method.isCallable())
        return QJSValue(QJSValue::UndefinedValue);
    if (method.isError()) {
        throw Error(method.toString().isEmpty() ? QString::fromLatin1("Unknown error.")
            : method.toString());
    }

    const QJSValue result = method.call(arguments);
    if (result.isError()) {
        throw Error(result.toString().isEmpty() ? QString::fromLatin1("Unknown error.")
            : result.toString());
    }

    stack.removeLast();
    m_callstack.insert(key, stack);
    return result.isUndefined() ? QJSValue(QJSValue::NullValue) : result;
}


// -- private slots

void ScriptEngine::setGuiQObject(QObject *guiQObject)
{
    m_guiProxy->setPackageManagerGui(qobject_cast<PackageManagerGui*>(guiQObject));
}


// -- private

#undef SETPROPERTY
#define SETPROPERTY(a, x, t) a.setProperty(QLatin1String(#x), QJSValue(t::x));

QJSValue ScriptEngine::generateWizardButtonsObject()
{
    QJSValue buttons = m_engine.newArray();
    SETPROPERTY(buttons, BackButton, QWizard)
    SETPROPERTY(buttons, NextButton, QWizard)
    SETPROPERTY(buttons, CommitButton, QWizard)
    SETPROPERTY(buttons, FinishButton, QWizard)
    SETPROPERTY(buttons, CancelButton, QWizard)
    SETPROPERTY(buttons, HelpButton, QWizard)
    SETPROPERTY(buttons, CustomButton1, QWizard)
    SETPROPERTY(buttons, CustomButton2, QWizard)
    SETPROPERTY(buttons, CustomButton3, QWizard)
    return buttons;
}

/*!
    \internal
    generates QMessageBox::StandardButton enum as an QScriptValue array
*/
QJSValue ScriptEngine::generateMessageBoxObject()
{
    QJSValue messageBox = m_engine.newQObject(MessageBoxHandler::instance());

    const QMetaObject &messageBoxMetaObject = QMessageBox::staticMetaObject;
    const int index = messageBoxMetaObject.indexOfEnumerator("StandardButtons");

    QJSValue value = m_engine.newArray();
    value.setProperty(QLatin1String("NoButton"), QJSValue(QMessageBox::NoButton));

    const QMetaEnum metaEnum = messageBoxMetaObject.enumerator(index);
    for (int i = 0; i < metaEnum.keyCount(); i++) {
        const int enumValue = metaEnum.value(i);
        if (enumValue >= QMessageBox::FirstButton)
            value.setProperty(QLatin1String(metaEnum.valueToKey(enumValue)), QJSValue(enumValue));
        if (enumValue == QMessageBox::LastButton)
            break;
    }

    messageBox.setPrototype(value);
    return messageBox;
}

QJSValue ScriptEngine::generateDesktopServicesObject()
{
    QJSValue desktopServices = m_engine.newArray();
    SETPROPERTY(desktopServices, DesktopLocation, QStandardPaths)
    SETPROPERTY(desktopServices, DocumentsLocation, QStandardPaths)
    SETPROPERTY(desktopServices, FontsLocation, QStandardPaths)
    SETPROPERTY(desktopServices, ApplicationsLocation, QStandardPaths)
    SETPROPERTY(desktopServices, MusicLocation, QStandardPaths)
    SETPROPERTY(desktopServices, MoviesLocation, QStandardPaths)
    SETPROPERTY(desktopServices, PicturesLocation, QStandardPaths)
    SETPROPERTY(desktopServices, TempLocation, QStandardPaths)
    SETPROPERTY(desktopServices, HomeLocation, QStandardPaths)
    SETPROPERTY(desktopServices, DataLocation, QStandardPaths)
    SETPROPERTY(desktopServices, CacheLocation, QStandardPaths)
    SETPROPERTY(desktopServices, GenericDataLocation, QStandardPaths)
    SETPROPERTY(desktopServices, RuntimeLocation, QStandardPaths)
    SETPROPERTY(desktopServices, ConfigLocation, QStandardPaths)
    SETPROPERTY(desktopServices, DownloadLocation, QStandardPaths)
    SETPROPERTY(desktopServices, GenericCacheLocation, QStandardPaths)
    SETPROPERTY(desktopServices, GenericConfigLocation, QStandardPaths)

    QJSValue object = m_engine.newQObject(new QDesktopServicesProxy);
    object.setPrototype(desktopServices);   // attach the properties
    return object;
}

QJSValue ScriptEngine::generateQInstallerObject()
{
    // register ::WizardPage enum in the script connection
    QJSValue qinstaller = m_engine.newArray();
    SETPROPERTY(qinstaller, Introduction, PackageManagerCore)
    SETPROPERTY(qinstaller, LicenseCheck, PackageManagerCore)
    SETPROPERTY(qinstaller, TargetDirectory, PackageManagerCore)
    SETPROPERTY(qinstaller, ComponentSelection, PackageManagerCore)
    SETPROPERTY(qinstaller, StartMenuSelection, PackageManagerCore)
    SETPROPERTY(qinstaller, ReadyForInstallation, PackageManagerCore)
    SETPROPERTY(qinstaller, PerformInstallation, PackageManagerCore)
    SETPROPERTY(qinstaller, InstallationFinished, PackageManagerCore)
    SETPROPERTY(qinstaller, End, PackageManagerCore)

    // register ::Status enum in the script connection
    SETPROPERTY(qinstaller, Success, PackageManagerCore)
    SETPROPERTY(qinstaller, Failure, PackageManagerCore)
    SETPROPERTY(qinstaller, Running, PackageManagerCore)
    SETPROPERTY(qinstaller, Canceled, PackageManagerCore)
    SETPROPERTY(qinstaller, Unfinished, PackageManagerCore)
    SETPROPERTY(qinstaller, ForceUpdate, PackageManagerCore)
    return qinstaller;
}

#undef SETPROPERTY

}   // namespace QInstaller