#include "BsEditorWidgetManager.h"
#include "BsEditorWidget.h"
#include "BsEditorWindow.h"
#include "BsEditorWidgetContainer.h"
#include "BsEditorWindowManager.h"
#include "BsMainEditorWindow.h"
#include "BsEditorWidgetLayout.h"
#include "BsDockManager.h"
#include "BsException.h"

namespace BansheeEngine
{
	Stack<std::pair<String, std::function<EditorWidgetBase*(EditorWidgetContainer&)>>> EditorWidgetManager::QueuedCreateCallbacks;

	EditorWidgetManager::EditorWidgetManager()
	{
		while(!QueuedCreateCallbacks.empty())
		{
			std::pair<String, std::function<EditorWidgetBase*(EditorWidgetContainer&)>> curElement = QueuedCreateCallbacks.top();
			QueuedCreateCallbacks.pop();

			registerWidget(curElement.first, curElement.second);
		}
	}

	void EditorWidgetManager::registerWidget(const String& name, std::function<EditorWidgetBase*(EditorWidgetContainer&)> createCallback)
	{
		auto iterFind = mCreateCallbacks.find(name);

		if(iterFind != mCreateCallbacks.end())
			BS_EXCEPT(InvalidParametersException, "Widget with the same name is already registered. Name: \"" + name + "\"");

		mCreateCallbacks[name] = createCallback;
	}

	EditorWidgetBase* EditorWidgetManager::open(const String& name)
	{
		auto iterFind = mActiveWidgets.find(name);

		if(iterFind != mActiveWidgets.end())
			return iterFind->second;

		EditorWindow* window = EditorWindow::create();
		EditorWidgetBase* newWidget = create(name, window->widgets());
		if(newWidget == nullptr)
		{
			window->close();
			return nullptr;
		}

		return newWidget;
	}

	void EditorWidgetManager::close(EditorWidgetBase* widget)
	{
		auto findIter = std::find_if(mActiveWidgets.begin(), mActiveWidgets.end(),
			[&] (const std::pair<String, EditorWidgetBase*>& entry) { return entry.second == widget; });

		if(findIter != mActiveWidgets.end())
			mActiveWidgets.erase(findIter);

		if(widget->mParent != nullptr)
			widget->mParent->_notifyWidgetDestroyed(widget);

		EditorWidgetBase::destroy(widget);
	}

	EditorWidgetBase* EditorWidgetManager::create(const String& name, EditorWidgetContainer& parentContainer)
	{
		auto iterFind = mActiveWidgets.find(name);

		if(iterFind != mActiveWidgets.end())
		{
			EditorWidgetBase* existingWidget = iterFind->second;
			if(existingWidget->_getParent() != nullptr && existingWidget->_getParent() != &parentContainer)
				existingWidget->_getParent()->remove(*existingWidget);

			if(existingWidget->_getParent() != &parentContainer)
				parentContainer.add(*iterFind->second);

			return iterFind->second;
		}

		auto iterFindCreate = mCreateCallbacks.find(name);
		if(iterFindCreate == mCreateCallbacks.end())
			return nullptr;

		EditorWidgetBase* newWidget = mCreateCallbacks[name](parentContainer);
		parentContainer.add(*newWidget);

		if(newWidget != nullptr)
			mActiveWidgets[name] = newWidget;

		return newWidget;
	}

	EditorWidgetLayoutPtr EditorWidgetManager::getLayout() const
	{
		auto GetWidgetNamesInContainer = [&] (const EditorWidgetContainer* container)
		{
			Vector<String> widgetNames;
			if(container != nullptr)
			{
				UINT32 numWidgets = container->getNumWidgets();

				for(UINT32 i = 0; i < numWidgets; i++)
				{
					EditorWidgetBase* widget = container->getWidget(i);
					widgetNames.push_back(widget->getName());
				}				
			}

			return widgetNames;
		};

		MainEditorWindow* mainWindow = EditorWindowManager::instance().getMainWindow();
		DockManager& dockManager = mainWindow->getDockManager();
		EditorWidgetLayoutPtr layout = bs_shared_ptr<EditorWidgetLayout>(dockManager.getLayout());

		Vector<EditorWidgetLayout::Entry>& layoutEntries = layout->getEntries();
		UnorderedSet<EditorWidgetContainer*> widgetContainers;

		for(auto& widget : mActiveWidgets)
		{
			widgetContainers.insert(widget.second->_getParent());
		}

		for(auto& widgetContainer : widgetContainers)
		{
			if(widgetContainer == nullptr)
				continue;

			layoutEntries.push_back(EditorWidgetLayout::Entry());
			EditorWidgetLayout::Entry& entry = layoutEntries.back();

			entry.widgetNames = GetWidgetNamesInContainer(widgetContainer);

			EditorWindow* parentWindow = widgetContainer->getParentWindow();
			entry.isDocked = parentWindow == nullptr;
			
			if(!entry.isDocked)
			{
				entry.x = parentWindow->getLeft();
				entry.y = parentWindow->getTop();
				entry.width = parentWindow->getWidth();
				entry.height = parentWindow->getHeight();
			}
		}

		return layout;
	}

	void EditorWidgetManager::setLayout(const EditorWidgetLayoutPtr& layout)
	{
		// Unparent all widgets
		Vector<EditorWidgetBase*> unparentedWidgets;
		for(auto& widget : mActiveWidgets)
		{
			if(widget.second->_getParent() != nullptr)
				widget.second->_getParent()->remove(*(widget.second));

			unparentedWidgets.push_back(widget.second);
		}

		// Restore floating widgets
		for(auto& entry : layout->getEntries())
		{
			if(entry.isDocked)
				continue;

			EditorWindow* window = EditorWindow::create();
			for(auto& widgetName : entry.widgetNames)
			{
				create(widgetName, window->widgets());
			}

			window->setPosition(entry.x, entry.y);
			window->setSize(entry.width, entry.height);

			if(window->widgets().getNumWidgets() == 0)
				window->close();
		}

		// Restore docked widgets
		MainEditorWindow* mainWindow = EditorWindowManager::instance().getMainWindow();
		DockManager& dockManager = mainWindow->getDockManager();

		dockManager.setLayout(layout->getDockLayout());

		// Destroy any widgets that are no longer have parents
		for(auto& widget : unparentedWidgets)
		{
			if(widget->_getParent() == nullptr)
				widget->close();
		}
	}

	void EditorWidgetManager::preRegisterWidget(const String& name, std::function<EditorWidgetBase*(EditorWidgetContainer&)> createCallback)
	{
		QueuedCreateCallbacks.push(std::pair<String, std::function<EditorWidgetBase*(EditorWidgetContainer&)>>(name, createCallback));
	}
}