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

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2020 - Raw Material Software Limited

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

   For this technical preview, this file is not subject to commercial licensing.

   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
{

const char* const Toolbar::toolbarDragDescriptor = "_toolbarItem_";

//==============================================================================
class Toolbar::Spacer  : public ToolbarItemComponent
{
public:
    Spacer (int itemID, float sizeToUse, bool shouldDrawBar)
        : ToolbarItemComponent (itemID, {}, false),
          fixedSize (sizeToUse),
          drawBar (shouldDrawBar)
    {
        setWantsKeyboardFocus (false);
    }

    bool getToolbarItemSizes (int toolbarThickness, bool /*isToolbarVertical*/,
                              int& preferredSize, int& minSize, int& maxSize) override
    {
        if (fixedSize <= 0)
        {
            preferredSize = toolbarThickness * 2;
            minSize = 4;
            maxSize = 32768;
        }
        else
        {
            maxSize = roundToInt (toolbarThickness * fixedSize);
            minSize = drawBar ? maxSize : jmin (4, maxSize);
            preferredSize = maxSize;

            if (getEditingMode() == editableOnPalette)
                preferredSize = maxSize = toolbarThickness / (drawBar ? 3 : 2);
        }

        return true;
    }

    void paintButtonArea (Graphics&, int, int, bool, bool) override
    {
    }

    void contentAreaChanged (const Rectangle<int>&) override
    {
    }

    int getResizeOrder() const noexcept
    {
        return fixedSize <= 0 ? 0 : 1;
    }

    void paint (Graphics& g) override
    {
        auto w = getWidth();
        auto h = getHeight();

        if (drawBar)
        {
            g.setColour (findColour (Toolbar::separatorColourId, true));

            auto thickness = 0.2f;

            if (isToolbarVertical())
                g.fillRect (w * 0.1f, h * (0.5f - thickness * 0.5f), w * 0.8f, h * thickness);
            else
                g.fillRect (w * (0.5f - thickness * 0.5f), h * 0.1f, w * thickness, h * 0.8f);
        }

        if (getEditingMode() != normalMode && ! drawBar)
        {
            g.setColour (findColour (Toolbar::separatorColourId, true));

            auto indentX = jmin (2, (w - 3) / 2);
            auto indentY = jmin (2, (h - 3) / 2);
            g.drawRect (indentX, indentY, w - indentX * 2, h - indentY * 2, 1);

            if (fixedSize <= 0)
            {
                float x1, y1, x2, y2, x3, y3, x4, y4, hw, hl;

                if (isToolbarVertical())
                {
                    x1 = w * 0.5f;
                    y1 = h * 0.4f;
                    x2 = x1;
                    y2 = indentX * 2.0f;

                    x3 = x1;
                    y3 = h * 0.6f;
                    x4 = x1;
                    y4 = h - y2;

                    hw = w * 0.15f;
                    hl = w * 0.2f;
                }
                else
                {
                    x1 = w * 0.4f;
                    y1 = h * 0.5f;
                    x2 = indentX * 2.0f;
                    y2 = y1;

                    x3 = w * 0.6f;
                    y3 = y1;
                    x4 = w - x2;
                    y4 = y1;

                    hw = h * 0.15f;
                    hl = h * 0.2f;
                }

                Path p;
                p.addArrow ({ x1, y1, x2, y2 }, 1.5f, hw, hl);
                p.addArrow ({ x3, y3, x4, y4 }, 1.5f, hw, hl);
                g.fillPath (p);
            }
        }
    }

private:
    const float fixedSize;
    const bool drawBar;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (Spacer)
};

//==============================================================================
class Toolbar::MissingItemsComponent  : public PopupMenu::CustomComponent
{
public:
    MissingItemsComponent (Toolbar& bar, int h)
        : PopupMenu::CustomComponent (true),
          owner (&bar),
          height (h)
    {
        for (int i = bar.items.size(); --i >= 0;)
        {
            auto* tc = bar.items.getUnchecked(i);

            if (dynamic_cast<Spacer*> (tc) == nullptr && ! tc->isVisible())
            {
                oldIndexes.insert (0, i);
                addAndMakeVisible (tc, 0);
            }
        }

        layout (400);
    }

    ~MissingItemsComponent() override
    {
        if (owner != nullptr)
        {
            for (int i = 0; i < getNumChildComponents(); ++i)
            {
                if (auto* tc = dynamic_cast<ToolbarItemComponent*> (getChildComponent (i)))
                {
                    tc->setVisible (false);
                    auto index = oldIndexes.removeAndReturn (i);
                    owner->addChildComponent (tc, index);
                    --i;
                }
            }

            owner->resized();
        }
    }

    void layout (const int preferredWidth)
    {
        const int indent = 8;
        auto x = indent;
        auto y = indent;
        int maxX = 0;

        for (auto* c : getChildren())
        {
            if (auto* tc = dynamic_cast<ToolbarItemComponent*> (c))
            {
                int preferredSize = 1, minSize = 1, maxSize = 1;

                if (tc->getToolbarItemSizes (height, false, preferredSize, minSize, maxSize))
                {
                    if (x + preferredSize > preferredWidth && x > indent)
                    {
                        x = indent;
                        y += height;
                    }

                    tc->setBounds (x, y, preferredSize, height);

                    x += preferredSize;
                    maxX = jmax (maxX, x);
                }
            }
        }

        setSize (maxX + 8, y + height + 8);
    }

    void getIdealSize (int& idealWidth, int& idealHeight) override
    {
        idealWidth = getWidth();
        idealHeight = getHeight();
    }

private:
    Component::SafePointer<Toolbar> owner;
    const int height;
    Array<int> oldIndexes;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (MissingItemsComponent)
};


//==============================================================================
Toolbar::Toolbar()
{
    missingItemsButton.reset (getLookAndFeel().createToolbarMissingItemsButton (*this));
    addChildComponent (missingItemsButton.get());

    missingItemsButton->setAlwaysOnTop (true);
    missingItemsButton->onClick = [this] { showMissingItems(); };
}

Toolbar::~Toolbar()
{
    items.clear();
}

void Toolbar::setVertical (const bool shouldBeVertical)
{
    if (vertical != shouldBeVertical)
    {
        vertical = shouldBeVertical;
        resized();
    }
}

void Toolbar::clear()
{
    items.clear();
    resized();
}

ToolbarItemComponent* Toolbar::createItem (ToolbarItemFactory& factory, const int itemId)
{
    if (itemId == ToolbarItemFactory::separatorBarId)    return new Spacer (itemId, 0.1f, true);
    if (itemId == ToolbarItemFactory::spacerId)          return new Spacer (itemId, 0.5f, false);
    if (itemId == ToolbarItemFactory::flexibleSpacerId)  return new Spacer (itemId, 0.0f, false);

    return factory.createItem (itemId);
}

void Toolbar::addItemInternal (ToolbarItemFactory& factory,
                               const int itemId,
                               const int insertIndex)
{
    // An ID can't be zero - this might indicate a mistake somewhere?
    jassert (itemId != 0);

    if (auto* tc = createItem (factory, itemId))
    {
       #if JUCE_DEBUG
        Array<int> allowedIds;
        factory.getAllToolbarItemIds (allowedIds);

        // If your factory can create an item for a given ID, it must also return
        // that ID from its getAllToolbarItemIds() method!
        jassert (allowedIds.contains (itemId));
       #endif

        items.insert (insertIndex, tc);
        addAndMakeVisible (tc, insertIndex);
    }
}

void Toolbar::addItem (ToolbarItemFactory& factory, int itemId, int insertIndex)
{
    addItemInternal (factory, itemId, insertIndex);
    resized();
}

void Toolbar::addDefaultItems (ToolbarItemFactory& factoryToUse)
{
    Array<int> ids;
    factoryToUse.getDefaultItemSet (ids);

    clear();

    for (auto i : ids)
        addItemInternal (factoryToUse, i, -1);

    resized();
}

void Toolbar::removeToolbarItem (const int itemIndex)
{
    items.remove (itemIndex);
    resized();
}

ToolbarItemComponent* Toolbar::removeAndReturnItem (const int itemIndex)
{
    if (auto* tc = items.removeAndReturn (itemIndex))
    {
        removeChildComponent (tc);
        resized();
        return tc;
    }

    return nullptr;
}

int Toolbar::getNumItems() const noexcept
{
    return items.size();
}

int Toolbar::getItemId (const int itemIndex) const noexcept
{
    if (auto* tc = getItemComponent (itemIndex))
        return tc->getItemId();

    return 0;
}

ToolbarItemComponent* Toolbar::getItemComponent (const int itemIndex) const noexcept
{
    return items[itemIndex];
}

ToolbarItemComponent* Toolbar::getNextActiveComponent (int index, const int delta) const
{
    for (;;)
    {
        index += delta;

        if (auto* tc = getItemComponent (index))
        {
            if (tc->isActive)
                return tc;
        }
        else
        {
            return nullptr;
        }
    }
}

void Toolbar::setStyle (const ToolbarItemStyle& newStyle)
{
    if (toolbarStyle != newStyle)
    {
        toolbarStyle = newStyle;
        updateAllItemPositions (false);
    }
}

String Toolbar::toString() const
{
    String s ("TB:");

    for (int i = 0; i < getNumItems(); ++i)
        s << getItemId(i) << ' ';

    return s.trimEnd();
}

bool Toolbar::restoreFromString (ToolbarItemFactory& factoryToUse,
                                 const String& savedVersion)
{
    if (! savedVersion.startsWith ("TB:"))
        return false;

    StringArray tokens;
    tokens.addTokens (savedVersion.substring (3), false);

    clear();

    for (auto& t : tokens)
        addItemInternal (factoryToUse, t.getIntValue(), -1);

    resized();
    return true;
}

void Toolbar::paint (Graphics& g)
{
    getLookAndFeel().paintToolbarBackground (g, getWidth(), getHeight(), *this);
}

int Toolbar::getThickness() const noexcept
{
    return vertical ? getWidth() : getHeight();
}

int Toolbar::getLength() const noexcept
{
    return vertical ? getHeight() : getWidth();
}

void Toolbar::setEditingActive (const bool active)
{
    if (isEditingActive != active)
    {
        isEditingActive = active;
        updateAllItemPositions (false);
    }
}

//==============================================================================
void Toolbar::resized()
{
    updateAllItemPositions (false);
}

void Toolbar::updateAllItemPositions (bool animate)
{
    if (getWidth() > 0 && getHeight() > 0)
    {
        StretchableObjectResizer resizer;

        for (auto* tc : items)
        {
            tc->setEditingMode (isEditingActive ? ToolbarItemComponent::editableOnToolbar
                                                : ToolbarItemComponent::normalMode);

            tc->setStyle (toolbarStyle);

            auto* spacer = dynamic_cast<Spacer*> (tc);

            int preferredSize = 1, minSize = 1, maxSize = 1;

            if (tc->getToolbarItemSizes (getThickness(), isVertical(),
                                         preferredSize, minSize, maxSize))
            {
                tc->isActive = true;
                resizer.addItem (preferredSize, minSize, maxSize,
                                 spacer != nullptr ? spacer->getResizeOrder() : 2);
            }
            else
            {
                tc->isActive = false;
                tc->setVisible (false);
            }
        }

        resizer.resizeToFit (getLength());

        int totalLength = 0;

        for (int i = 0; i < resizer.getNumItems(); ++i)
            totalLength += (int) resizer.getItemSize (i);

        const bool itemsOffTheEnd = totalLength > getLength();

        auto extrasButtonSize = getThickness() / 2;
        missingItemsButton->setSize (extrasButtonSize, extrasButtonSize);
        missingItemsButton->setVisible (itemsOffTheEnd);
        missingItemsButton->setEnabled (! isEditingActive);

        if (vertical)
            missingItemsButton->setCentrePosition (getWidth() / 2,
                                                   getHeight() - 4 - extrasButtonSize / 2);
        else
            missingItemsButton->setCentrePosition (getWidth() - 4 - extrasButtonSize / 2,
                                                   getHeight() / 2);

        auto maxLength = itemsOffTheEnd ? (vertical ? missingItemsButton->getY()
                                                    : missingItemsButton->getX()) - 4
                                        : getLength();

        int pos = 0, activeIndex = 0;

        for (auto* tc : items)
        {
            if (tc->isActive)
            {
                auto size = (int) resizer.getItemSize (activeIndex++);

                Rectangle<int> newBounds;

                if (vertical)
                    newBounds.setBounds (0, pos, getWidth(), size);
                else
                    newBounds.setBounds (pos, 0, size, getHeight());

                auto& animator = Desktop::getInstance().getAnimator();

                if (animate)
                {
                    animator.animateComponent (tc, newBounds, 1.0f, 200, false, 3.0, 0.0);
                }
                else
                {
                    animator.cancelAnimation (tc, false);
                    tc->setBounds (newBounds);
                }

                pos += size;
                tc->setVisible (pos <= maxLength
                                 && ((! tc->isBeingDragged)
                                      || tc->getEditingMode() == ToolbarItemComponent::editableOnPalette));
            }
        }
    }
}

//==============================================================================
void Toolbar::showMissingItems()
{
    jassert (missingItemsButton->isShowing());

    if (missingItemsButton->isShowing())
    {
        PopupMenu m;
        auto comp = std::make_unique<MissingItemsComponent> (*this, getThickness());
        m.addCustomItem (1, std::move (comp));
        m.showMenuAsync (PopupMenu::Options().withTargetComponent (missingItemsButton.get()));
    }
}

//==============================================================================
bool Toolbar::isInterestedInDragSource (const SourceDetails& dragSourceDetails)
{
    return dragSourceDetails.description == toolbarDragDescriptor && isEditingActive;
}

void Toolbar::itemDragMove (const SourceDetails& dragSourceDetails)
{
    if (auto* tc = dynamic_cast<ToolbarItemComponent*> (dragSourceDetails.sourceComponent.get()))
    {
        if (! items.contains (tc))
        {
            if (tc->getEditingMode() == ToolbarItemComponent::editableOnPalette)
            {
                if (auto* palette = tc->findParentComponentOfClass<ToolbarItemPalette>())
                    palette->replaceComponent (*tc);
            }
            else
            {
                jassert (tc->getEditingMode() == ToolbarItemComponent::editableOnToolbar);
            }

            items.add (tc);
            addChildComponent (tc);
            updateAllItemPositions (true);
        }

        auto& animator = Desktop::getInstance().getAnimator();

        for (int i = getNumItems(); --i >= 0;)
        {
            auto currentIndex = items.indexOf (tc);
            auto newIndex = currentIndex;

            auto dragObjectLeft = vertical ? (dragSourceDetails.localPosition.getY() - tc->dragOffsetY)
                                           : (dragSourceDetails.localPosition.getX() - tc->dragOffsetX);
            auto dragObjectRight = dragObjectLeft + (vertical ? tc->getHeight() : tc->getWidth());

            auto current = animator.getComponentDestination (getChildComponent (newIndex));

            if (auto* prev = getNextActiveComponent (newIndex, -1))
            {
                auto previousPos = animator.getComponentDestination (prev);

                if (std::abs (dragObjectLeft - (vertical ? previousPos.getY() : previousPos.getX()))
                     < std::abs (dragObjectRight - (vertical ? current.getBottom() : current.getRight())))
                {
                    newIndex = getIndexOfChildComponent (prev);
                }
            }

            if (auto* next = getNextActiveComponent (newIndex, 1))
            {
                auto nextPos = animator.getComponentDestination (next);

                if (std::abs (dragObjectLeft - (vertical ? current.getY() : current.getX()))
                     > std::abs (dragObjectRight - (vertical ? nextPos.getBottom() : nextPos.getRight())))
                {
                    newIndex = getIndexOfChildComponent (next) + 1;
                }
            }

            if (newIndex == currentIndex)
                break;

            items.removeObject (tc, false);
            removeChildComponent (tc);
            addChildComponent (tc, newIndex);
            items.insert (newIndex, tc);
            updateAllItemPositions (true);
        }
    }
}

void Toolbar::itemDragExit (const SourceDetails& dragSourceDetails)
{
    if (auto* tc = dynamic_cast<ToolbarItemComponent*> (dragSourceDetails.sourceComponent.get()))
    {
        if (isParentOf (tc))
        {
            items.removeObject (tc, false);
            removeChildComponent (tc);
            updateAllItemPositions (true);
        }
    }
}

void Toolbar::itemDropped (const SourceDetails& dragSourceDetails)
{
    if (auto* tc = dynamic_cast<ToolbarItemComponent*> (dragSourceDetails.sourceComponent.get()))
        tc->setState (Button::buttonNormal);
}

void Toolbar::mouseDown (const MouseEvent&) {}

//==============================================================================
class Toolbar::CustomisationDialog   : public DialogWindow
{
public:
    CustomisationDialog (ToolbarItemFactory& factory, Toolbar& bar, int optionFlags)
        : DialogWindow (TRANS("Add/remove items from toolbar"), Colours::white, true, true),
          toolbar (bar)
    {
        setContentOwned (new CustomiserPanel (factory, toolbar, optionFlags), true);
        setResizable (true, true);
        setResizeLimits (400, 300, 1500, 1000);
        positionNearBar();
    }

    ~CustomisationDialog() override
    {
        toolbar.setEditingActive (false);
    }

    void closeButtonPressed() override
    {
        setVisible (false);
    }

    bool canModalEventBeSentToComponent (const Component* comp) override
    {
        return toolbar.isParentOf (comp)
                 || dynamic_cast<const ToolbarItemComponent::ItemDragAndDropOverlayComponent*> (comp) != nullptr;
    }

    void positionNearBar()
    {
        auto screenSize = toolbar.getParentMonitorArea();
        auto pos = toolbar.getScreenPosition();
        const int gap = 8;

        if (toolbar.isVertical())
        {
            if (pos.x > screenSize.getCentreX())
                pos.x -= getWidth() - gap;
            else
                pos.x += toolbar.getWidth() + gap;
        }
        else
        {
            pos.x += (toolbar.getWidth() - getWidth()) / 2;

            if (pos.y > screenSize.getCentreY())
                pos.y -= getHeight() - gap;
            else
                pos.y += toolbar.getHeight() + gap;
        }

        setTopLeftPosition (pos);
    }

private:
    Toolbar& toolbar;

    class CustomiserPanel  : public Component
    {
    public:
        CustomiserPanel (ToolbarItemFactory& tbf, Toolbar& bar, int optionFlags)
           : factory (tbf), toolbar (bar), palette (tbf, bar),
             instructions ({}, TRANS ("You can drag the items above and drop them onto a toolbar to add them.")
                                 + "\n\n"
                                 + TRANS ("Items on the toolbar can also be dragged around to change their order, or dragged off the edge to delete them.")),
             defaultButton (TRANS ("Restore to default set of items"))
        {
            addAndMakeVisible (palette);

            if ((optionFlags & (Toolbar::allowIconsOnlyChoice
                                 | Toolbar::allowIconsWithTextChoice
                                 | Toolbar::allowTextOnlyChoice)) != 0)
            {
                addAndMakeVisible (styleBox);
                styleBox.setEditableText (false);

                if ((optionFlags & Toolbar::allowIconsOnlyChoice) != 0)     styleBox.addItem (TRANS("Show icons only"), 1);
                if ((optionFlags & Toolbar::allowIconsWithTextChoice) != 0) styleBox.addItem (TRANS("Show icons and descriptions"), 2);
                if ((optionFlags & Toolbar::allowTextOnlyChoice) != 0)      styleBox.addItem (TRANS("Show descriptions only"), 3);

                int selectedStyle = 0;
                switch (bar.getStyle())
                {
                    case Toolbar::iconsOnly:      selectedStyle = 1; break;
                    case Toolbar::iconsWithText:  selectedStyle = 2; break;
                    case Toolbar::textOnly:       selectedStyle = 3; break;
                    default:                      break;
                }

                styleBox.setSelectedId (selectedStyle);

                styleBox.onChange = [this] { updateStyle(); };
            }

            if ((optionFlags & Toolbar::showResetToDefaultsButton) != 0)
            {
                addAndMakeVisible (defaultButton);
                defaultButton.onClick = [this] { toolbar.addDefaultItems (factory); };
            }

            addAndMakeVisible (instructions);
            instructions.setFont (Font (13.0f));

            setSize (500, 300);
        }

        void updateStyle()
        {
            switch (styleBox.getSelectedId())
            {
                case 1:   toolbar.setStyle (Toolbar::iconsOnly); break;
                case 2:   toolbar.setStyle (Toolbar::iconsWithText); break;
                case 3:   toolbar.setStyle (Toolbar::textOnly); break;
                default:  break;
            }

            palette.resized(); // to make it update the styles
        }

        void paint (Graphics& g) override
        {
            Colour background;

            if (auto* dw = findParentComponentOfClass<DialogWindow>())
                background = dw->getBackgroundColour();

            g.setColour (background.contrasting().withAlpha (0.3f));
            g.fillRect (palette.getX(), palette.getBottom() - 1, palette.getWidth(), 1);
        }

        void resized() override
        {
            palette.setBounds (0, 0, getWidth(), getHeight() - 120);
            styleBox.setBounds (10, getHeight() - 110, 200, 22);

            defaultButton.changeWidthToFitText (22);
            defaultButton.setTopLeftPosition (240, getHeight() - 110);

            instructions.setBounds (10, getHeight() - 80, getWidth() - 20, 80);
        }

    private:
        ToolbarItemFactory& factory;
        Toolbar& toolbar;

        ToolbarItemPalette palette;
        Label instructions;
        ComboBox styleBox;
        TextButton defaultButton;
    };
};

void Toolbar::showCustomisationDialog (ToolbarItemFactory& factory, const int optionFlags)
{
    setEditingActive (true);

    (new CustomisationDialog (factory, *this, optionFlags))
        ->enterModalState (true, nullptr, true);
}

} // namespace juce