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

   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
{

class KeyMappingEditorComponent::ChangeKeyButton  : public Button
{
public:
    ChangeKeyButton (KeyMappingEditorComponent& kec, CommandID command,
                     const String& keyName, int keyIndex)
        : Button (keyName),
          owner (kec),
          commandID (command),
          keyNum (keyIndex)
    {
        setWantsKeyboardFocus (false);
        setTriggeredOnMouseDown (keyNum >= 0);

        setTooltip (keyIndex < 0 ? TRANS("Adds a new key-mapping")
                                 : TRANS("Click to change this key-mapping"));
    }

    void paintButton (Graphics& g, bool /*isOver*/, bool /*isDown*/) override
    {
        getLookAndFeel().drawKeymapChangeButton (g, getWidth(), getHeight(), *this,
                                                 keyNum >= 0 ? getName() : String());
    }

    void clicked() override
    {
        if (keyNum >= 0)
        {
            Component::SafePointer<ChangeKeyButton> button (this);
            PopupMenu m;

            m.addItem (TRANS("Change this key-mapping"),
                       [button]
                       {
                           if (button != nullptr)
                               button.getComponent()->assignNewKey();
                       });

            m.addSeparator();

            m.addItem (TRANS("Remove this key-mapping"),
                       [button]
                       {
                           if (button != nullptr)
                               button->owner.getMappings().removeKeyPress (button->commandID,
                                                                           button->keyNum);
                       });

            m.showMenuAsync (PopupMenu::Options().withTargetComponent (this));
        }
        else
        {
            assignNewKey();  // + button pressed..
        }
    }

    using Button::clicked;

    void fitToContent (const int h) noexcept
    {
        if (keyNum < 0)
            setSize (h, h);
        else
            setSize (jlimit (h * 4, h * 8, 6 + Font (h * 0.6f).getStringWidth (getName())), h);
    }

    //==============================================================================
    class KeyEntryWindow  : public AlertWindow
    {
    public:
        KeyEntryWindow (KeyMappingEditorComponent& kec)
            : AlertWindow (TRANS("New key-mapping"),
                           TRANS("Please press a key combination now..."),
                           AlertWindow::NoIcon),
              owner (kec)
        {
            addButton (TRANS("OK"), 1);
            addButton (TRANS("Cancel"), 0);

            // (avoid return + escape keys getting processed by the buttons..)
            for (auto* child : getChildren())
                child->setWantsKeyboardFocus (false);

            setWantsKeyboardFocus (true);
            grabKeyboardFocus();
        }

        bool keyPressed (const KeyPress& key) override
        {
            lastPress = key;
            String message (TRANS("Key") + ": " + owner.getDescriptionForKeyPress (key));

            auto previousCommand = owner.getMappings().findCommandForKeyPress (key);

            if (previousCommand != 0)
                message << "\n\n("
                        << TRANS("Currently assigned to \"CMDN\"")
                            .replace ("CMDN", TRANS (owner.getCommandManager().getNameOfCommand (previousCommand)))
                        << ')';

            setMessage (message);
            return true;
        }

        bool keyStateChanged (bool) override
        {
            return true;
        }

        KeyPress lastPress;

    private:
        KeyMappingEditorComponent& owner;

        JUCE_DECLARE_NON_COPYABLE (KeyEntryWindow)
    };

    static void assignNewKeyCallback (int result, ChangeKeyButton* button, KeyPress newKey)
    {
        if (result != 0 && button != nullptr)
            button->setNewKey (newKey, true);
    }

    void setNewKey (const KeyPress& newKey, bool dontAskUser)
    {
        if (newKey.isValid())
        {
            auto previousCommand = owner.getMappings().findCommandForKeyPress (newKey);

            if (previousCommand == 0 || dontAskUser)
            {
                owner.getMappings().removeKeyPress (newKey);

                if (keyNum >= 0)
                    owner.getMappings().removeKeyPress (commandID, keyNum);

                owner.getMappings().addKeyPress (commandID, newKey, keyNum);
            }
            else
            {
                AlertWindow::showOkCancelBox (AlertWindow::WarningIcon,
                                              TRANS("Change key-mapping"),
                                              TRANS("This key is already assigned to the command \"CMDN\"")
                                                  .replace ("CMDN", owner.getCommandManager().getNameOfCommand (previousCommand))
                                                + "\n\n"
                                                + TRANS("Do you want to re-assign it to this new command instead?"),
                                              TRANS("Re-assign"),
                                              TRANS("Cancel"),
                                              this,
                                              ModalCallbackFunction::forComponent (assignNewKeyCallback,
                                                                                   this, KeyPress (newKey)));
            }
        }
    }

    static void keyChosen (int result, ChangeKeyButton* button)
    {
        if (button != nullptr && button->currentKeyEntryWindow != nullptr)
        {
            if (result != 0)
            {
                button->currentKeyEntryWindow->setVisible (false);
                button->setNewKey (button->currentKeyEntryWindow->lastPress, false);
            }

            button->currentKeyEntryWindow.reset();
        }
    }

    void assignNewKey()
    {
        currentKeyEntryWindow.reset (new KeyEntryWindow (owner));
        currentKeyEntryWindow->enterModalState (true, ModalCallbackFunction::forComponent (keyChosen, this));
    }

private:
    KeyMappingEditorComponent& owner;
    const CommandID commandID;
    const int keyNum;
    std::unique_ptr<KeyEntryWindow> currentKeyEntryWindow;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (ChangeKeyButton)
};

//==============================================================================
class KeyMappingEditorComponent::ItemComponent  : public Component
{
public:
    ItemComponent (KeyMappingEditorComponent& kec, CommandID command)
        : owner (kec), commandID (command)
    {
        setInterceptsMouseClicks (false, true);

        const bool isReadOnly = owner.isCommandReadOnly (commandID);

        auto keyPresses = owner.getMappings().getKeyPressesAssignedToCommand (commandID);

        for (int i = 0; i < jmin ((int) maxNumAssignments, keyPresses.size()); ++i)
            addKeyPressButton (owner.getDescriptionForKeyPress (keyPresses.getReference (i)), i, isReadOnly);

        addKeyPressButton (String(), -1, isReadOnly);
    }

    void addKeyPressButton (const String& desc, const int index, const bool isReadOnly)
    {
        auto* b = new ChangeKeyButton (owner, commandID, desc, index);
        keyChangeButtons.add (b);

        b->setEnabled (! isReadOnly);
        b->setVisible (keyChangeButtons.size() <= (int) maxNumAssignments);
        addChildComponent (b);
    }

    void paint (Graphics& g) override
    {
        g.setFont (getHeight() * 0.7f);
        g.setColour (owner.findColour (KeyMappingEditorComponent::textColourId));

        g.drawFittedText (TRANS (owner.getCommandManager().getNameOfCommand (commandID)),
                          4, 0, jmax (40, getChildComponent (0)->getX() - 5), getHeight(),
                          Justification::centredLeft, true);
    }

    void resized() override
    {
        int x = getWidth() - 4;

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

            b->fitToContent (getHeight() - 2);
            b->setTopRightPosition (x, 1);
            x = b->getX() - 5;
        }
    }

private:
    KeyMappingEditorComponent& owner;
    OwnedArray<ChangeKeyButton> keyChangeButtons;
    const CommandID commandID;

    enum { maxNumAssignments = 3 };

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (ItemComponent)
};

//==============================================================================
class KeyMappingEditorComponent::MappingItem  : public TreeViewItem
{
public:
    MappingItem (KeyMappingEditorComponent& kec, CommandID command)
        : owner (kec), commandID (command)
    {}

    String getUniqueName() const override         { return String ((int) commandID) + "_id"; }
    bool mightContainSubItems() override          { return false; }
    int getItemHeight() const override            { return 20; }
    Component* createItemComponent() override     { return new ItemComponent (owner, commandID); }

private:
    KeyMappingEditorComponent& owner;
    const CommandID commandID;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (MappingItem)
};


//==============================================================================
class KeyMappingEditorComponent::CategoryItem  : public TreeViewItem
{
public:
    CategoryItem (KeyMappingEditorComponent& kec, const String& name)
        : owner (kec), categoryName (name)
    {}

    String getUniqueName() const override       { return categoryName + "_cat"; }
    bool mightContainSubItems() override        { return true; }
    int getItemHeight() const override          { return 22; }

    void paintItem (Graphics& g, int width, int height) override
    {
        g.setFont (Font (height * 0.7f, Font::bold));
        g.setColour (owner.findColour (KeyMappingEditorComponent::textColourId));

        g.drawText (TRANS (categoryName), 2, 0, width - 2, height, Justification::centredLeft, true);
    }

    void itemOpennessChanged (bool isNowOpen) override
    {
        if (isNowOpen)
        {
            if (getNumSubItems() == 0)
                for (auto command : owner.getCommandManager().getCommandsInCategory (categoryName))
                    if (owner.shouldCommandBeIncluded (command))
                        addSubItem (new MappingItem (owner, command));
        }
        else
        {
            clearSubItems();
        }
    }

private:
    KeyMappingEditorComponent& owner;
    String categoryName;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (CategoryItem)
};

//==============================================================================
class KeyMappingEditorComponent::TopLevelItem   : public TreeViewItem,
                                                  private ChangeListener
{
public:
    TopLevelItem (KeyMappingEditorComponent& kec)   : owner (kec)
    {
        setLinesDrawnForSubItems (false);
        owner.getMappings().addChangeListener (this);
    }

    ~TopLevelItem() override
    {
        owner.getMappings().removeChangeListener (this);
    }

    bool mightContainSubItems() override             { return true; }
    String getUniqueName() const override            { return "keys"; }

    void changeListenerCallback (ChangeBroadcaster*) override
    {
        const OpennessRestorer opennessRestorer (*this);
        clearSubItems();

        for (auto category : owner.getCommandManager().getCommandCategories())
        {
            int count = 0;

            for (auto command : owner.getCommandManager().getCommandsInCategory (category))
                if (owner.shouldCommandBeIncluded (command))
                    ++count;

            if (count > 0)
                addSubItem (new CategoryItem (owner, category));
        }
    }

private:
    KeyMappingEditorComponent& owner;
};

static void resetKeyMappingsToDefaultsCallback (int result, KeyMappingEditorComponent* owner)
{
    if (result != 0 && owner != nullptr)
        owner->getMappings().resetToDefaultMappings();
}

//==============================================================================
KeyMappingEditorComponent::KeyMappingEditorComponent (KeyPressMappingSet& mappingManager,
                                                      const bool showResetToDefaultButton)
    : mappings (mappingManager),
      resetButton (TRANS ("reset to defaults"))
{
    treeItem.reset (new TopLevelItem (*this));

    if (showResetToDefaultButton)
    {
        addAndMakeVisible (resetButton);

        resetButton.onClick = [this]
        {
            AlertWindow::showOkCancelBox (AlertWindow::QuestionIcon,
                                          TRANS("Reset to defaults"),
                                          TRANS("Are you sure you want to reset all the key-mappings to their default state?"),
                                          TRANS("Reset"),
                                          {}, this,
                                          ModalCallbackFunction::forComponent (resetKeyMappingsToDefaultsCallback, this));
        };
    }

    addAndMakeVisible (tree);
    tree.setColour (TreeView::backgroundColourId, findColour (backgroundColourId));
    tree.setRootItemVisible (false);
    tree.setDefaultOpenness (true);
    tree.setRootItem (treeItem.get());
    tree.setIndentSize (12);
}

KeyMappingEditorComponent::~KeyMappingEditorComponent()
{
    tree.setRootItem (nullptr);
}

//==============================================================================
void KeyMappingEditorComponent::setColours (Colour mainBackground,
                                            Colour textColour)
{
    setColour (backgroundColourId, mainBackground);
    setColour (textColourId, textColour);
    tree.setColour (TreeView::backgroundColourId, mainBackground);
}

void KeyMappingEditorComponent::parentHierarchyChanged()
{
    treeItem->changeListenerCallback (nullptr);
}

void KeyMappingEditorComponent::resized()
{
    int h = getHeight();

    if (resetButton.isVisible())
    {
        const int buttonHeight = 20;
        h -= buttonHeight + 8;
        int x = getWidth() - 8;

        resetButton.changeWidthToFitText (buttonHeight);
        resetButton.setTopRightPosition (x, h + 6);
    }

    tree.setBounds (0, 0, getWidth(), h);
}

//==============================================================================
bool KeyMappingEditorComponent::shouldCommandBeIncluded (const CommandID commandID)
{
    auto* ci = mappings.getCommandManager().getCommandForID (commandID);

    return ci != nullptr && (ci->flags & ApplicationCommandInfo::hiddenFromKeyEditor) == 0;
}

bool KeyMappingEditorComponent::isCommandReadOnly (const CommandID commandID)
{
    auto* ci = mappings.getCommandManager().getCommandForID (commandID);

    return ci != nullptr && (ci->flags & ApplicationCommandInfo::readOnlyInKeyEditor) != 0;
}

String KeyMappingEditorComponent::getDescriptionForKeyPress (const KeyPress& key)
{
    return key.getTextDescription();
}

} // namespace juce