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

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

   JUCE is an open source framework subject to commercial or open source
   licensing.

   By downloading, installing, or using the JUCE framework, or combining the
   JUCE framework with any other source code, object code, content or any other
   copyrightable work, you agree to the terms of the JUCE End User Licence
   Agreement, and all incorporated terms including the JUCE Privacy Policy and
   the JUCE Website Terms of Service, as applicable, which will bind you. If you
   do not agree to the terms of these agreements, we will not license the JUCE
   framework to you, and you must discontinue the installation or download
   process and cease use of the JUCE framework.

   JUCE End User Licence Agreement: https://juce.com/legal/juce-8-licence/
   JUCE Privacy Policy: https://juce.com/juce-privacy-policy
   JUCE Website Terms of Service: https://juce.com/juce-website-terms-of-service/

   Or:

   You may also use this code under the terms of the AGPLv3:
   https://www.gnu.org/licenses/agpl-3.0.en.html

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

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

namespace juce
{

KeyPressMappingSet::KeyPressMappingSet (ApplicationCommandManager& cm)
    : commandManager (cm)
{
    Desktop::getInstance().addFocusChangeListener (this);
}

KeyPressMappingSet::KeyPressMappingSet (const KeyPressMappingSet& other)
    : KeyListener(), ChangeBroadcaster(), FocusChangeListener(), commandManager (other.commandManager)
{
    Desktop::getInstance().addFocusChangeListener (this);
}

KeyPressMappingSet::~KeyPressMappingSet()
{
    Desktop::getInstance().removeFocusChangeListener (this);
}

//==============================================================================
Array<KeyPress> KeyPressMappingSet::getKeyPressesAssignedToCommand (const CommandID commandID) const
{
    for (int i = 0; i < mappings.size(); ++i)
        if (mappings.getUnchecked (i)->commandID == commandID)
            return mappings.getUnchecked (i)->keypresses;

    return {};
}

void KeyPressMappingSet::addKeyPress (const CommandID commandID, const KeyPress& newKeyPress, int insertIndex)
{
    // If you specify an upper-case letter but no shift key, how is the user supposed to press it!?
    // Stick to lower-case letters when defining a keypress, to avoid ambiguity.
    jassert (! (CharacterFunctions::isUpperCase (newKeyPress.getTextCharacter())
                 && ! newKeyPress.getModifiers().isShiftDown()));

    if (findCommandForKeyPress (newKeyPress) != commandID)
    {
        if (newKeyPress.isValid())
        {
            for (int i = mappings.size(); --i >= 0;)
            {
                if (mappings.getUnchecked (i)->commandID == commandID)
                {
                    mappings.getUnchecked (i)->keypresses.insert (insertIndex, newKeyPress);

                    sendChangeMessage();
                    return;
                }
            }

            if (const ApplicationCommandInfo* const ci = commandManager.getCommandForID (commandID))
            {
                CommandMapping* const cm = new CommandMapping();
                cm->commandID = commandID;
                cm->keypresses.add (newKeyPress);
                cm->wantsKeyUpDownCallbacks = (ci->flags & ApplicationCommandInfo::wantsKeyUpDownCallbacks) != 0;

                mappings.add (cm);
                sendChangeMessage();
            }
            else
            {
                // If you hit this, you're trying to attach a keypress to a command ID that
                // doesn't exist, so the key is not being attached.
                jassertfalse;
            }
        }
    }
}

static void addKeyPresses (KeyPressMappingSet& set, const ApplicationCommandInfo* const ci)
{
    for (int j = 0; j < ci->defaultKeypresses.size(); ++j)
        set.addKeyPress (ci->commandID, ci->defaultKeypresses.getReference (j));
}

void KeyPressMappingSet::resetToDefaultMappings()
{
    mappings.clear();

    for (int i = 0; i < commandManager.getNumCommands(); ++i)
        addKeyPresses (*this, commandManager.getCommandForIndex (i));

    sendChangeMessage();
}

void KeyPressMappingSet::resetToDefaultMapping (const CommandID commandID)
{
    clearAllKeyPresses (commandID);

    if (const ApplicationCommandInfo* const ci = commandManager.getCommandForID (commandID))
        addKeyPresses (*this, ci);
}

void KeyPressMappingSet::clearAllKeyPresses()
{
    if (mappings.size() > 0)
    {
        sendChangeMessage();
        mappings.clear();
    }
}

void KeyPressMappingSet::clearAllKeyPresses (const CommandID commandID)
{
    for (int i = mappings.size(); --i >= 0;)
    {
        if (mappings.getUnchecked (i)->commandID == commandID)
        {
            mappings.remove (i);
            sendChangeMessage();
        }
    }
}

void KeyPressMappingSet::removeKeyPress (const KeyPress& keypress)
{
    if (keypress.isValid())
    {
        for (int i = mappings.size(); --i >= 0;)
        {
            CommandMapping& cm = *mappings.getUnchecked (i);

            for (int j = cm.keypresses.size(); --j >= 0;)
            {
                if (keypress == cm.keypresses [j])
                {
                    cm.keypresses.remove (j);
                    sendChangeMessage();
                }
            }
        }
    }
}

void KeyPressMappingSet::removeKeyPress (const CommandID commandID, const int keyPressIndex)
{
    for (int i = mappings.size(); --i >= 0;)
    {
        if (mappings.getUnchecked (i)->commandID == commandID)
        {
            mappings.getUnchecked (i)->keypresses.remove (keyPressIndex);
            sendChangeMessage();
            break;
        }
    }
}

//==============================================================================
CommandID KeyPressMappingSet::findCommandForKeyPress (const KeyPress& keyPress) const noexcept
{
    for (int i = 0; i < mappings.size(); ++i)
        if (mappings.getUnchecked (i)->keypresses.contains (keyPress))
            return mappings.getUnchecked (i)->commandID;

    return 0;
}

bool KeyPressMappingSet::containsMapping (const CommandID commandID, const KeyPress& keyPress) const noexcept
{
    for (int i = mappings.size(); --i >= 0;)
        if (mappings.getUnchecked (i)->commandID == commandID)
            return mappings.getUnchecked (i)->keypresses.contains (keyPress);

    return false;
}

void KeyPressMappingSet::invokeCommand (const CommandID commandID,
                                        const KeyPress& key,
                                        const bool isKeyDown,
                                        const int millisecsSinceKeyPressed,
                                        Component* const originatingComponent) const
{
    ApplicationCommandTarget::InvocationInfo info (commandID);

    info.invocationMethod = ApplicationCommandTarget::InvocationInfo::fromKeyPress;
    info.isKeyDown = isKeyDown;
    info.keyPress = key;
    info.millisecsSinceKeyPressed = millisecsSinceKeyPressed;
    info.originatingComponent = originatingComponent;

    commandManager.invoke (info, false);
}

//==============================================================================
bool KeyPressMappingSet::restoreFromXml (const XmlElement& xmlVersion)
{
    if (xmlVersion.hasTagName ("KEYMAPPINGS"))
    {
        if (xmlVersion.getBoolAttribute ("basedOnDefaults", true))
        {
            // if the XML was created as a set of differences from the default mappings,
            // (i.e. by calling createXml (true)), then we need to first restore the defaults.
            resetToDefaultMappings();
        }
        else
        {
            // if the XML was created calling createXml (false), then we need to clear all
            // the keys and treat the xml as describing the entire set of mappings.
            clearAllKeyPresses();
        }

        for (auto* map : xmlVersion.getChildIterator())
        {
            const CommandID commandId = map->getStringAttribute ("commandId").getHexValue32();

            if (commandId != 0)
            {
                auto key = KeyPress::createFromDescription (map->getStringAttribute ("key"));

                if (map->hasTagName ("MAPPING"))
                {
                    addKeyPress (commandId, key);
                }
                else if (map->hasTagName ("UNMAPPING"))
                {
                    for (auto& m : mappings)
                        if (m->commandID == commandId)
                            m->keypresses.removeAllInstancesOf (key);
                }
            }
        }

        return true;
    }

    return false;
}

std::unique_ptr<XmlElement> KeyPressMappingSet::createXml (const bool saveDifferencesFromDefaultSet) const
{
    std::unique_ptr<KeyPressMappingSet> defaultSet;

    if (saveDifferencesFromDefaultSet)
    {
        defaultSet = std::make_unique<KeyPressMappingSet> (commandManager);
        defaultSet->resetToDefaultMappings();
    }

    auto doc = std::make_unique<XmlElement> ("KEYMAPPINGS");

    doc->setAttribute ("basedOnDefaults", saveDifferencesFromDefaultSet);

    for (int i = 0; i < mappings.size(); ++i)
    {
        auto& cm = *mappings.getUnchecked (i);

        for (int j = 0; j < cm.keypresses.size(); ++j)
        {
            if (defaultSet == nullptr
                 || ! defaultSet->containsMapping (cm.commandID, cm.keypresses.getReference (j)))
            {
                auto map = doc->createNewChildElement ("MAPPING");

                map->setAttribute ("commandId", String::toHexString ((int) cm.commandID));
                map->setAttribute ("description", commandManager.getDescriptionOfCommand (cm.commandID));
                map->setAttribute ("key", cm.keypresses.getReference (j).getTextDescription());
            }
        }
    }

    if (defaultSet != nullptr)
    {
        for (int i = 0; i < defaultSet->mappings.size(); ++i)
        {
            auto& cm = *defaultSet->mappings.getUnchecked (i);

            for (int j = 0; j < cm.keypresses.size(); ++j)
            {
                if (! containsMapping (cm.commandID, cm.keypresses.getReference (j)))
                {
                    auto map = doc->createNewChildElement ("UNMAPPING");

                    map->setAttribute ("commandId", String::toHexString ((int) cm.commandID));
                    map->setAttribute ("description", commandManager.getDescriptionOfCommand (cm.commandID));
                    map->setAttribute ("key", cm.keypresses.getReference (j).getTextDescription());
                }
            }
        }
    }

    return doc;
}

//==============================================================================
bool KeyPressMappingSet::keyPressed (const KeyPress& key, Component* const originatingComponent)
{
    bool commandWasDisabled = false;

    for (int i = 0; i < mappings.size(); ++i)
    {
        CommandMapping& cm = *mappings.getUnchecked (i);

        if (cm.keypresses.contains (key))
        {
            if (const ApplicationCommandInfo* const ci = commandManager.getCommandForID (cm.commandID))
            {
                if ((ci->flags & ApplicationCommandInfo::wantsKeyUpDownCallbacks) == 0)
                {
                    ApplicationCommandInfo info (0);

                    if (commandManager.getTargetForCommand (cm.commandID, info) != nullptr)
                    {
                        if ((info.flags & ApplicationCommandInfo::isDisabled) == 0)
                        {
                            invokeCommand (cm.commandID, key, true, 0, originatingComponent);
                            return true;
                        }

                        commandWasDisabled = true;
                    }
                }
            }
        }
    }

    if (originatingComponent != nullptr && commandWasDisabled)
        originatingComponent->getLookAndFeel().playAlertSound();

    return false;
}

bool KeyPressMappingSet::keyStateChanged (const bool /*isKeyDown*/, Component* originatingComponent)
{
    bool used = false;
    const uint32 now = Time::getMillisecondCounter();

    for (int i = mappings.size(); --i >= 0;)
    {
        CommandMapping& cm = *mappings.getUnchecked (i);

        if (cm.wantsKeyUpDownCallbacks)
        {
            for (int j = cm.keypresses.size(); --j >= 0;)
            {
                const KeyPress key (cm.keypresses.getReference (j));
                const bool isDown = key.isCurrentlyDown();

                int keyPressEntryIndex = 0;
                bool wasDown = false;

                for (int k = keysDown.size(); --k >= 0;)
                {
                    if (key == keysDown.getUnchecked (k)->key)
                    {
                        keyPressEntryIndex = k;
                        wasDown = true;
                        used = true;
                        break;
                    }
                }

                if (isDown != wasDown)
                {
                    int millisecs = 0;

                    if (isDown)
                    {
                        KeyPressTime* const k = new KeyPressTime();
                        k->key = key;
                        k->timeWhenPressed = now;

                        keysDown.add (k);
                    }
                    else
                    {
                        const uint32 pressTime = keysDown.getUnchecked (keyPressEntryIndex)->timeWhenPressed;

                        if (now > pressTime)
                            millisecs = (int) (now - pressTime);

                        keysDown.remove (keyPressEntryIndex);
                    }

                    invokeCommand (cm.commandID, key, isDown, millisecs, originatingComponent);
                    used = true;
                }
            }
        }
    }

    return used;
}

void KeyPressMappingSet::globalFocusChanged (Component* focusedComponent)
{
    if (focusedComponent != nullptr)
        focusedComponent->keyStateChanged (false);
}

} // namespace juce
