JUCE/modules/juce_gui_basics/windows/juce_AlertWindow.cpp

/*
  ==============================================================================

   This file is part of the JUCE library.
   Copyright (c) 2020 - Raw Material Software Limited

   JUCE is an open source library subject to commercial or open-source
   licensing.

   By using JUCE, you agree to the terms of both the JUCE 6 End-User License
   Agreement and JUCE Privacy Policy (both effective as of the 16th June 2020).

   End User License Agreement: www.juce.com/juce-6-licence
   Privacy Policy: www.juce.com/juce-privacy-policy

   Or: You may also use this code under the terms of the GPL v3 (see
   www.gnu.org/licenses).

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

static juce_wchar getDefaultPasswordChar() noexcept
{
   #if JUCE_LINUX || JUCE_BSD
    return 0x2022;
   #else
    return 0x25cf;
   #endif
}

//==============================================================================
AlertWindow::AlertWindow (const String& title,
                          const String& message,
                          MessageBoxIconType iconType,
                          Component* comp)
   : TopLevelWindow (title, true),
     alertIconType (iconType),
     associatedComponent (comp),
     desktopScale (comp != nullptr ? Component::getApproximateScaleFactorForComponent (comp) : 1.0f)
{
    setAlwaysOnTop (juce_areThereAnyAlwaysOnTopWindows());

    accessibleMessageLabel.setColour (Label::textColourId, Colours::transparentBlack);
    addAndMakeVisible (accessibleMessageLabel);

    if (message.isEmpty())
        text = " "; // to force an update if the message is empty

    setMessage (message);

    AlertWindow::lookAndFeelChanged();
    constrainer.setMinimumOnscreenAmounts (0x10000, 0x10000, 0x10000, 0x10000);
}

AlertWindow::~AlertWindow()
{
    // Ensure that the focus does not jump to another TextEditor while we
    // remove children.
    for (auto* t : textBoxes)
        t->setWantsKeyboardFocus (false);

    // Give away focus before removing the editors, so that any TextEditor
    // with focus has a chance to dismiss native keyboard if shown.
    giveAwayKeyboardFocus();

    removeAllChildren();
}

void AlertWindow::userTriedToCloseWindow()
{
    if (escapeKeyCancels || buttons.size() > 0)
        exitModalState (0);
}

//==============================================================================
void AlertWindow::setMessage (const String& message)
{
    auto newMessage = message.substring (0, 2048);

    if (text != newMessage)
    {
        text = newMessage;

        auto accessibleText = getName() + ". " + text;
        accessibleMessageLabel.setText (accessibleText, NotificationType::dontSendNotification);
        setDescription (accessibleText);

        updateLayout (true);
        repaint();
    }
}

//==============================================================================
void AlertWindow::exitAlert (Button* button)
{
    if (auto* parent = button->getParentComponent())
        parent->exitModalState (button->getCommandID());
}

//==============================================================================
void AlertWindow::addButton (const String& name,
                             const int returnValue,
                             const KeyPress& shortcutKey1,
                             const KeyPress& shortcutKey2)
{
    auto* b = new TextButton (name, {});
    buttons.add (b);

    b->setWantsKeyboardFocus (true);
    b->setExplicitFocusOrder (1);
    b->setMouseClickGrabsKeyboardFocus (false);
    b->setCommandToTrigger (nullptr, returnValue, false);
    b->addShortcut (shortcutKey1);
    b->addShortcut (shortcutKey2);
    b->onClick = [this, b] { exitAlert (b); };

    Array<TextButton*> buttonsArray (buttons.begin(), buttons.size());
    auto& lf = getLookAndFeel();

    auto buttonHeight = lf.getAlertWindowButtonHeight();
    auto buttonWidths = lf.getWidthsForTextButtons (*this, buttonsArray);

    jassert (buttonWidths.size() == buttons.size());
    int i = 0;

    for (auto* button : buttons)
        button->setSize (buttonWidths[i++], buttonHeight);

    addAndMakeVisible (b, 0);
    updateLayout (false);
}

int AlertWindow::getNumButtons() const
{
    return buttons.size();
}

void AlertWindow::triggerButtonClick (const String& buttonName)
{
    for (auto* b : buttons)
    {
        if (buttonName == b->getName())
        {
            b->triggerClick();
            break;
        }
    }
}

void AlertWindow::setEscapeKeyCancels (bool shouldEscapeKeyCancel)
{
    escapeKeyCancels = shouldEscapeKeyCancel;
}

//==============================================================================
void AlertWindow::addTextEditor (const String& name,
                                 const String& initialContents,
                                 const String& onScreenLabel,
                                 const bool isPasswordBox)
{
    auto* ed = new TextEditor (name, isPasswordBox ? getDefaultPasswordChar() : 0);
    ed->setSelectAllWhenFocused (true);
    ed->setEscapeAndReturnKeysConsumed (false);
    textBoxes.add (ed);
    allComps.add (ed);

    ed->setColour (TextEditor::outlineColourId, findColour (ComboBox::outlineColourId));
    ed->setFont (getLookAndFeel().getAlertWindowMessageFont());
    addAndMakeVisible (ed);
    ed->setText (initialContents);
    ed->setCaretPosition (initialContents.length());
    textboxNames.add (onScreenLabel);

    updateLayout (false);
}

TextEditor* AlertWindow::getTextEditor (const String& nameOfTextEditor) const
{
    for (auto* tb : textBoxes)
        if (tb->getName() == nameOfTextEditor)
            return tb;

    return nullptr;
}

String AlertWindow::getTextEditorContents (const String& nameOfTextEditor) const
{
    if (auto* t = getTextEditor (nameOfTextEditor))
        return t->getText();

    return {};
}


//==============================================================================
void AlertWindow::addComboBox (const String& name,
                               const StringArray& items,
                               const String& onScreenLabel)
{
    auto* cb = new ComboBox (name);
    comboBoxes.add (cb);
    allComps.add (cb);

    cb->addItemList (items, 1);

    addAndMakeVisible (cb);
    cb->setSelectedItemIndex (0);

    comboBoxNames.add (onScreenLabel);
    updateLayout (false);
}

ComboBox* AlertWindow::getComboBoxComponent (const String& nameOfList) const
{
    for (auto* cb : comboBoxes)
        if (cb->getName() == nameOfList)
            return cb;

    return nullptr;
}

//==============================================================================
class AlertTextComp  : public TextEditor
{
public:
    AlertTextComp (AlertWindow& owner, const String& message, const Font& font)
    {
        if (owner.isColourSpecified (AlertWindow::textColourId))
            setColour (TextEditor::textColourId, owner.findColour (AlertWindow::textColourId));

        setColour (TextEditor::backgroundColourId, Colours::transparentBlack);
        setColour (TextEditor::outlineColourId, Colours::transparentBlack);
        setColour (TextEditor::shadowColourId, Colours::transparentBlack);

        setReadOnly (true);
        setMultiLine (true, true);
        setCaretVisible (false);
        setScrollbarsShown (true);
        lookAndFeelChanged();
        setWantsKeyboardFocus (false);
        setFont (font);
        setText (message, false);

        bestWidth = 2 * (int) std::sqrt (font.getHeight() * (float) font.getStringWidth (message));
    }

    void updateLayout (const int width)
    {
        AttributedString s;
        s.setJustification (Justification::topLeft);
        s.append (getText(), getFont());

        TextLayout text;
        text.createLayoutWithBalancedLineLengths (s, (float) width - 8.0f);
        setSize (width, jmin (width, (int) (text.getHeight() + getFont().getHeight())));
    }

    int bestWidth;

    JUCE_DECLARE_NON_COPYABLE (AlertTextComp)
};

void AlertWindow::addTextBlock (const String& textBlock)
{
    auto* c = new AlertTextComp (*this, textBlock, getLookAndFeel().getAlertWindowMessageFont());
    textBlocks.add (c);
    allComps.add (c);
    addAndMakeVisible (c);

    updateLayout (false);
}

//==============================================================================
void AlertWindow::addProgressBarComponent (double& progressValue)
{
    auto* pb = new ProgressBar (progressValue);
    progressBars.add (pb);
    allComps.add (pb);
    addAndMakeVisible (pb);

    updateLayout (false);
}

//==============================================================================
void AlertWindow::addCustomComponent (Component* const component)
{
    customComps.add (component);
    allComps.add (component);
    addAndMakeVisible (component);

    updateLayout (false);
}

int AlertWindow::getNumCustomComponents() const                 { return customComps.size(); }
Component* AlertWindow::getCustomComponent (int index) const    { return customComps [index]; }

Component* AlertWindow::removeCustomComponent (const int index)
{
    auto* c = getCustomComponent (index);

    if (c != nullptr)
    {
        customComps.removeFirstMatchingValue (c);
        allComps.removeFirstMatchingValue (c);
        removeChildComponent (c);

        updateLayout (false);
    }

    return c;
}

//==============================================================================
void AlertWindow::paint (Graphics& g)
{
    auto& lf = getLookAndFeel();
    lf.drawAlertBox (g, *this, textArea, textLayout);

    g.setColour (findColour (textColourId));
    g.setFont (lf.getAlertWindowFont());

    for (int i = textBoxes.size(); --i >= 0;)
    {
        auto* te = textBoxes.getUnchecked(i);

        g.drawFittedText (textboxNames[i],
                          te->getX(), te->getY() - 14,
                          te->getWidth(), 14,
                          Justification::centredLeft, 1);
    }

    for (int i = comboBoxNames.size(); --i >= 0;)
    {
        auto* cb = comboBoxes.getUnchecked(i);

        g.drawFittedText (comboBoxNames[i],
                          cb->getX(), cb->getY() - 14,
                          cb->getWidth(), 14,
                          Justification::centredLeft, 1);
    }

    for (auto* c : customComps)
        g.drawFittedText (c->getName(),
                          c->getX(), c->getY() - 14,
                          c->getWidth(), 14,
                          Justification::centredLeft, 1);
}

void AlertWindow::updateLayout (const bool onlyIncreaseSize)
{
    const int titleH = 24;
    const int iconWidth = 80;

    auto& lf = getLookAndFeel();
    auto messageFont (lf.getAlertWindowMessageFont());

    auto wid = jmax (messageFont.getStringWidth (text),
                     messageFont.getStringWidth (getName()));

    auto sw = (int) std::sqrt (messageFont.getHeight() * (float) wid);
    auto w = jmin (300 + sw * 2, (int) ((float) getParentWidth() * 0.7f));
    const int edgeGap = 10;
    const int labelHeight = 18;
    int iconSpace = 0;

    AttributedString attributedText;
    attributedText.append (getName(), lf.getAlertWindowTitleFont());

    if (text.isNotEmpty())
        attributedText.append ("\n\n" + text, messageFont);

    attributedText.setColour (findColour (textColourId));

    if (alertIconType == NoIcon)
    {
        attributedText.setJustification (Justification::centredTop);
        textLayout.createLayoutWithBalancedLineLengths (attributedText, (float) w);
    }
    else
    {
        attributedText.setJustification (Justification::topLeft);
        textLayout.createLayoutWithBalancedLineLengths (attributedText, (float) w);
        iconSpace = iconWidth;
    }

    w = jmax (350, (int) textLayout.getWidth() + iconSpace + edgeGap * 4);
    w = jmin (w, (int) ((float) getParentWidth() * 0.7f));

    auto textLayoutH = (int) textLayout.getHeight();
    auto textBottom = 16 + titleH + textLayoutH;
    int h = textBottom;

    int buttonW = 40;

    for (auto* b : buttons)
        buttonW += 16 + b->getWidth();

    w = jmax (buttonW, w);

    h += (textBoxes.size() + comboBoxes.size() + progressBars.size()) * 50;

    if (auto* b = buttons[0])
        h += 20 + b->getHeight();

    for (auto* c : customComps)
    {
        w = jmax (w, (c->getWidth() * 100) / 80);
        h += 10 + c->getHeight();

        if (c->getName().isNotEmpty())
            h += labelHeight;
    }

    for (auto* tb : textBlocks)
        w = jmax (w, static_cast<const AlertTextComp*> (tb)->bestWidth);

    w = jmin (w, (int) ((float) getParentWidth() * 0.7f));

    for (auto* tb : textBlocks)
    {
        auto* ac = static_cast<AlertTextComp*> (tb);
        ac->updateLayout ((int) ((float) w * 0.8f));
        h += ac->getHeight() + 10;
    }

    h = jmin (getParentHeight() - 50, h);

    if (onlyIncreaseSize)
    {
        w = jmax (w, getWidth());
        h = jmax (h, getHeight());
    }

    if (! isVisible())
        centreAroundComponent (associatedComponent, w, h);
    else
        setBounds (getBounds().withSizeKeepingCentre (w, h));

    textArea.setBounds (edgeGap, edgeGap, w - (edgeGap * 2), h - edgeGap);
    accessibleMessageLabel.setBounds (textArea);

    const int spacer = 16;
    int totalWidth = -spacer;

    for (auto* b : buttons)
        totalWidth += b->getWidth() + spacer;

    auto x = (w - totalWidth) / 2;
    auto y = (int) ((float) getHeight() * 0.95f);

    for (auto* c : buttons)
    {
        int ny = proportionOfHeight (0.95f) - c->getHeight();
        c->setTopLeftPosition (x, ny);
        if (ny < y)
            y = ny;

        x += c->getWidth() + spacer;

        c->toFront (false);
    }

    y = textBottom;

    for (auto* c : allComps)
    {
        h = 22;

        const int comboIndex = comboBoxes.indexOf (dynamic_cast<ComboBox*> (c));
        if (comboIndex >= 0 && comboBoxNames [comboIndex].isNotEmpty())
            y += labelHeight;

        const int tbIndex = textBoxes.indexOf (dynamic_cast<TextEditor*> (c));
        if (tbIndex >= 0 && textboxNames[tbIndex].isNotEmpty())
            y += labelHeight;

        if (customComps.contains (c))
        {
            if (c->getName().isNotEmpty())
                y += labelHeight;

            c->setTopLeftPosition (proportionOfWidth (0.1f), y);
            h = c->getHeight();
        }
        else if (textBlocks.contains (c))
        {
            c->setTopLeftPosition ((getWidth() - c->getWidth()) / 2, y);
            h = c->getHeight();
        }
        else
        {
            c->setBounds (proportionOfWidth (0.1f), y, proportionOfWidth (0.8f), h);
        }

        y += h + 10;
    }

    setWantsKeyboardFocus (getNumChildComponents() == 0);
}

bool AlertWindow::containsAnyExtraComponents() const
{
    return allComps.size() > 0;
}

//==============================================================================
void AlertWindow::mouseDown (const MouseEvent& e)
{
    dragger.startDraggingComponent (this, e);
}

void AlertWindow::mouseDrag (const MouseEvent& e)
{
    dragger.dragComponent (this, e, &constrainer);
}

bool AlertWindow::keyPressed (const KeyPress& key)
{
    for (auto* b : buttons)
    {
        if (b->isRegisteredForShortcut (key))
        {
            b->triggerClick();
            return true;
        }
    }

    if (key.isKeyCode (KeyPress::escapeKey) && escapeKeyCancels)
    {
        exitModalState (0);
        return true;
    }

    if (key.isKeyCode (KeyPress::returnKey) && buttons.size() == 1)
    {
        buttons.getUnchecked(0)->triggerClick();
        return true;
    }

    return false;
}

void AlertWindow::lookAndFeelChanged()
{
    const int newFlags = getLookAndFeel().getAlertBoxWindowFlags();

    setUsingNativeTitleBar ((newFlags & ComponentPeer::windowHasTitleBar) != 0);
    setDropShadowEnabled (isOpaque() && (newFlags & ComponentPeer::windowHasDropShadow) != 0);
    updateLayout (false);
}

int AlertWindow::getDesktopWindowStyleFlags() const
{
    return getLookAndFeel().getAlertBoxWindowFlags();
}

enum class Async { no, yes };

//==============================================================================
class AlertWindowInfo
{
public:
    AlertWindowInfo (const MessageBoxOptions& opts,
                     std::unique_ptr<ModalComponentManager::Callback>&& cb,
                     Async showAsync)
        : options (opts),
          callback (std::move (cb)),
          async (showAsync)
    {
    }

    int invoke() const
    {
        MessageManager::getInstance()->callFunctionOnMessageThread (showCallback, (void*) this);
        return returnValue;
    }

private:
    static void* showCallback (void* userData)
    {
        static_cast<AlertWindowInfo*> (userData)->show();
        return nullptr;
    }

    void show()
    {
        auto* component = options.getAssociatedComponent();

        auto& lf = (component != nullptr ? component->getLookAndFeel()
                                         : LookAndFeel::getDefaultLookAndFeel());

        std::unique_ptr<AlertWindow> alertBox (lf.createAlertWindow (options.getTitle(), options.getMessage(),
                                                                     options.getButtonText (0), options.getButtonText (1), options.getButtonText (2),
                                                                     options.getIconType(), options.getNumButtons(), component));

        jassert (alertBox != nullptr); // you have to return one of these!

        alertBox->setAlwaysOnTop (juce_areThereAnyAlwaysOnTopWindows());

       #if JUCE_MODAL_LOOPS_PERMITTED
        if (async == Async::no)
            returnValue = alertBox->runModalLoop();
        else
       #endif
        {
            ignoreUnused (async);

            alertBox->enterModalState (true, callback.release(), true);
            alertBox.release();
        }
    }

    MessageBoxOptions options;
    std::unique_ptr<ModalComponentManager::Callback> callback;
    const Async async;
    int returnValue = 0;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (AlertWindowInfo)
};

namespace AlertWindowMappings
{
    static int messageBox (int)               { return 0; }
    static int okCancel (int buttonIndex)     { return buttonIndex == 0 ? 1 : 0; }
    static int yesNoCancel (int buttonIndex)  { return buttonIndex == 2 ? 0 : buttonIndex + 1; }

    ModalComponentManager::Callback* getWrappedCallback (ModalComponentManager::Callback* callbackIn,
                                                         std::function<int (int)> mapFn)
    {
        if (callbackIn == nullptr)
            return nullptr;

        auto wrappedCallback = [innerCallback = rawToUniquePtr (callbackIn), mapFn] (int buttonIndex)
        {
            innerCallback->modalStateFinished (mapFn (buttonIndex));
        };

        return ModalCallbackFunction::create (std::move (wrappedCallback));
    }
}

#if JUCE_MODAL_LOOPS_PERMITTED
void AlertWindow::showMessageBox (MessageBoxIconType iconType,
                                  const String& title,
                                  const String& message,
                                  const String& buttonText,
                                  Component* associatedComponent)
{
    show (MessageBoxOptions()
            .withIconType (iconType)
            .withTitle (title)
            .withMessage (message)
            .withButton (buttonText.isEmpty() ? TRANS("OK") : buttonText)
            .withAssociatedComponent (associatedComponent));
}

int AlertWindow::show (const MessageBoxOptions& options)
{
    if (LookAndFeel::getDefaultLookAndFeel().isUsingNativeAlertWindows())
        return NativeMessageBox::show (options);

    AlertWindowInfo info (options, nullptr, Async::no);
    return info.invoke();
}
#endif

void AlertWindow::showAsync (const MessageBoxOptions& options, ModalComponentManager::Callback* callback)
{
    if (LookAndFeel::getDefaultLookAndFeel().isUsingNativeAlertWindows())
    {
        NativeMessageBox::showAsync (options, callback);
    }
    else
    {
        AlertWindowInfo info (options, rawToUniquePtr (callback), Async::yes);
        info.invoke();
    }
}

void AlertWindow::showAsync (const MessageBoxOptions& options, std::function<void (int)> callback)
{
    showAsync (options, ModalCallbackFunction::create (callback));
}

void AlertWindow::showMessageBoxAsync (MessageBoxIconType iconType,
                                       const String& title,
                                       const String& message,
                                       const String& buttonText,
                                       Component* associatedComponent,
                                       ModalComponentManager::Callback* callback)
{
    if (LookAndFeel::getDefaultLookAndFeel().isUsingNativeAlertWindows())
        callback = AlertWindowMappings::getWrappedCallback (callback, AlertWindowMappings::messageBox);

    showAsync (MessageBoxOptions()
                 .withIconType (iconType)
                 .withTitle (title)
                 .withMessage (message)
                 .withButton (buttonText.isEmpty() ? TRANS("OK") : buttonText)
                 .withAssociatedComponent (associatedComponent),
               callback);
}

static int showMaybeAsync (const MessageBoxOptions& options,
                           std::unique_ptr<ModalComponentManager::Callback> callback)
{
    const auto showAsync = (callback != nullptr ? Async::yes
                                                : Async::no);

    if (LookAndFeel::getDefaultLookAndFeel().isUsingNativeAlertWindows())
    {
       #if JUCE_MODAL_LOOPS_PERMITTED
        if (showAsync == Async::no)
            return NativeMessageBox::show (options);
       #endif

        NativeMessageBox::showAsync (options, callback.release());
        return false;
    }

    AlertWindowInfo info (options, std::move (callback), showAsync);
    return info.invoke();
}

bool AlertWindow::showOkCancelBox (MessageBoxIconType iconType,
                                   const String& title,
                                   const String& message,
                                   const String& button1Text,
                                   const String& button2Text,
                                   Component* associatedComponent,
                                   ModalComponentManager::Callback* callback)
{
    if (LookAndFeel::getDefaultLookAndFeel().isUsingNativeAlertWindows())
        callback = AlertWindowMappings::getWrappedCallback (callback, AlertWindowMappings::okCancel);

    return showMaybeAsync (MessageBoxOptions()
                             .withIconType (iconType)
                             .withTitle (title)
                             .withMessage (message)
                             .withButton (button1Text.isEmpty() ? TRANS("OK")     : button1Text)
                             .withButton (button2Text.isEmpty() ? TRANS("Cancel") : button2Text)
                             .withAssociatedComponent (associatedComponent),
                           rawToUniquePtr (callback)) == 1;
}

int AlertWindow::showYesNoCancelBox (MessageBoxIconType iconType,
                                     const String& title,
                                     const String& message,
                                     const String& button1Text,
                                     const String& button2Text,
                                     const String& button3Text,
                                     Component* associatedComponent,
                                     ModalComponentManager::Callback* callback)
{
    if (LookAndFeel::getDefaultLookAndFeel().isUsingNativeAlertWindows())
        callback = AlertWindowMappings::getWrappedCallback (callback, AlertWindowMappings::yesNoCancel);

    return showMaybeAsync (MessageBoxOptions()
                             .withIconType (iconType)
                             .withTitle (title)
                             .withMessage (message)
                             .withButton (button1Text.isEmpty() ? TRANS("Yes")    : button1Text)
                             .withButton (button2Text.isEmpty() ? TRANS("No")     : button2Text)
                             .withButton (button3Text.isEmpty() ? TRANS("Cancel") : button3Text)
                             .withAssociatedComponent (associatedComponent),
                           rawToUniquePtr (callback));
}

//==============================================================================
std::unique_ptr<AccessibilityHandler> AlertWindow::createAccessibilityHandler()
{
    return std::make_unique<AccessibilityHandler> (*this, AccessibilityRole::dialogWindow);
}

} // namespace juce