#ifndef _TEXTLISTCOMPONENT_H_
#define _TEXTLISTCOMPONENT_H_

#include "../Renderer.h"
#include "../resources/Font.h"
#include "../GuiComponent.h"
#include "../InputManager.h"
#include <vector>
#include <string>
#include <memory>
#include "../Sound.h"
#include "../Log.h"
#include "../ThemeData.h"
#include <functional>

//A graphical list. Supports multiple colors for rows and scrolling.
template <typename T>
class TextListComponent : public GuiComponent
{
public:
	TextListComponent(Window* window);
	virtual ~TextListComponent();

	bool input(InputConfig* config, Input input) override;
	void update(int deltaTime) override;
	void render(const Eigen::Affine3f& parentTrans) override;
	void applyTheme(const std::shared_ptr<ThemeData>& theme, const std::string& view, const std::string& element, unsigned int properties) override;

	struct ListRow
	{
		std::string name;
		T object;
		unsigned int colorId;
		std::shared_ptr<TextCache> textCache;
	};

	void add(const std::string& name, const T& obj, unsigned int colorId);
	void remove(const T& obj);
	void clear();

	inline const std::string& getSelectedName() const { return mRowVector.at(mCursor).name; }
	inline T getSelected() const { return mRowVector.at(mCursor).object; }
	inline const std::vector<ListRow>& getList() const { return mRowVector; }

	void setCursor(const T& select);
	void setCursor(typename std::vector<ListRow>::const_iterator& it);

	void stopScrolling();
	inline bool isScrolling() const { return mScrollDir != 0; }

	enum CursorState
	{
		CURSOR_STOPPED,
		CURSOR_SCROLLING
	};

	enum Alignment
	{
		ALIGN_LEFT,
		ALIGN_CENTER,
		ALIGN_RIGHT
	};

	inline void setAlignment(Alignment align) { mAlignment = align; }

	inline void setCursorChangedCallback(const std::function<void(CursorState state)>& func) { mCursorChangedCallback = func; }

	inline void setFont(const std::shared_ptr<Font>& font)
	{
		mFont = font;
		for(auto it = mRowVector.begin(); it != mRowVector.end(); it++)
			it->textCache.reset();
	}

	inline void setSelectorColor(unsigned int color) { mSelectorColor = color; }
	inline void setSelectedColor(unsigned int color) { mSelectedColor = color; }
	inline void setScrollSound(const std::shared_ptr<Sound>& sound) { mScrollSound = sound; }
	inline void setColor(unsigned int id, unsigned int color) { mColors[id] = color; }
	inline void setSound(const std::shared_ptr<Sound>& sound) { mScrollSound = sound; }

private:
	static const int MARQUEE_DELAY = 900;
	static const int MARQUEE_SPEED = 16;
	static const int MARQUEE_RATE = 3;

	static const int SCROLL_DELAY = 507;
	static const int SCROLL_TIME = 150;

	void scroll(); //helper method, scrolls in whatever direction scrollDir is
	void setScrollDir(int val); //helper method, set mScrollDir as well as reset marquee stuff
	void onCursorChanged(CursorState state);

	int mScrollDir, mScrollAccumulator;

	int mMarqueeOffset;
	int mMarqueeTime;

	Alignment mAlignment;
	float mHorizontalMargin;

	std::vector<ListRow> mRowVector;
	int mCursor;

	std::function<void(CursorState state)> mCursorChangedCallback;

	std::shared_ptr<Font> mFont;
	unsigned int mSelectorColor;
	unsigned int mSelectedColor;
	std::shared_ptr<Sound> mScrollSound;
	static const unsigned int COLOR_ID_COUNT = 2;
	unsigned int mColors[COLOR_ID_COUNT];
};

template <typename T>
TextListComponent<T>::TextListComponent(Window* window) : 
	GuiComponent(window)
{
	mCursor = 0;
	mScrollDir = 0;
	mScrollAccumulator = 0;

	mMarqueeOffset = 0;
	mMarqueeTime = -MARQUEE_DELAY;

	mHorizontalMargin = 0;
	mAlignment = ALIGN_CENTER;

	mFont = Font::get(FONT_SIZE_MEDIUM);
	mSelectorColor = 0x000000FF;
	mSelectedColor = 0;
	mColors[0] = 0x0000FFFF;
	mColors[1] = 0x00FF00FF;
}

template <typename T>
TextListComponent<T>::~TextListComponent()
{
}

template <typename T>
void TextListComponent<T>::render(const Eigen::Affine3f& parentTrans)
{
	Eigen::Affine3f trans = parentTrans * getTransform();
	
	std::shared_ptr<Font>& font = mFont;

	const int cutoff = 0;
	const int entrySize = font->getHeight() + 5;

	int startEntry = 0;

	//number of entries that can fit on the screen simultaniously
	int screenCount = (int)mSize.y() / entrySize;
	
	if((int)mRowVector.size() >= screenCount)
	{
		startEntry = mCursor - (int)(screenCount * 0.5);
		if(startEntry < 0)
			startEntry = 0;
		if(startEntry >= (int)mRowVector.size() - screenCount)
			startEntry = mRowVector.size() - screenCount;
	}

	float y = (float)cutoff;

	if(mRowVector.size() == 0)
	{
		font->drawCenteredText("The list is empty.", 0, y, 0xFF0000FF);
		return;
	}

	int listCutoff = startEntry + screenCount;
	if(listCutoff > (int)mRowVector.size())
		listCutoff = mRowVector.size();

	Eigen::Vector3f dim(getSize().x(), getSize().y(), 0);
	dim = trans * dim - trans.translation();
	Renderer::pushClipRect(Eigen::Vector2i((int)trans.translation().x(), (int)trans.translation().y()), Eigen::Vector2i((int)dim.x(), (int)dim.y()));

	for(int i = startEntry; i < listCutoff; i++)
	{
		//draw selector bar
		if(mCursor == i)
		{
			Renderer::setMatrix(trans);
			Renderer::drawRect(0, (int)y, (int)getSize().x(), font->getHeight(), mSelectorColor);
		}

		ListRow& row = mRowVector.at((unsigned int)i);

		unsigned int color;
		if(mCursor == i && mSelectedColor)
			color = mSelectedColor;
		else
			color = mColors[row.colorId];

		if(!row.textCache)
			row.textCache = std::unique_ptr<TextCache>(font->buildTextCache(row.name, 0, 0, 0x000000FF));

		row.textCache->setColor(color);

		Eigen::Vector3f offset(0, y, 0);

		switch(mAlignment)
		{
		case ALIGN_LEFT:
			offset[0] = mHorizontalMargin;
			break;
		case ALIGN_CENTER:
			offset[0] = (mSize.x() - row.textCache->metrics.size.x()) / 2;
			if(offset[0] < 0)
				offset[0] = 0;
			break;
		case ALIGN_RIGHT:
			offset[0] = (mSize.x() - row.textCache->metrics.size.x());
			offset[0] -= mHorizontalMargin;
			if(offset[0] < 0)
				offset[0] = 0;

			break;
		}
		
		if(mCursor == i)
			offset[0] -= mMarqueeOffset;
		
		Eigen::Affine3f drawTrans = trans;
		drawTrans.translate(offset);
		Renderer::setMatrix(drawTrans);

		font->renderTextCache(row.textCache.get());
		
		y += entrySize;
	}

	Renderer::popClipRect();

	GuiComponent::renderChildren(trans);
}

template <typename T>
bool TextListComponent<T>::input(InputConfig* config, Input input)
{
	if(mRowVector.size() > 0)
	{
		if(input.value != 0)
		{
			if(config->isMappedTo("down", input))
			{
				setScrollDir(1);
				scroll();
				return true;
			}

			if(config->isMappedTo("up", input))
			{
				setScrollDir(-1);
				scroll();
				return true;
			}
			if(config->isMappedTo("pagedown", input))
			{
				setScrollDir(10);
				scroll();
				return true;
			}

			if(config->isMappedTo("pageup", input))
			{
				setScrollDir(-10);
				scroll();
				return true;
			}
		}else{
			if(config->isMappedTo("down", input) || config->isMappedTo("up", input) || 
				config->isMappedTo("pagedown", input) || config->isMappedTo("pageup", input))
			{
				stopScrolling();
			}
		}
	}

	return GuiComponent::input(config, input);
}

template <typename T>
void TextListComponent<T>::setScrollDir(int val)
{
	mScrollDir = val;
	mMarqueeOffset = 0;
	mMarqueeTime = -MARQUEE_DELAY;
	mScrollAccumulator = -SCROLL_DELAY;
}

template <typename T>
void TextListComponent<T>::stopScrolling()
{
	mScrollAccumulator = 0;
	mScrollDir = 0;
	onCursorChanged(CURSOR_STOPPED);
}

template <typename T>
void TextListComponent<T>::update(int deltaTime)
{
	if(mScrollDir != 0)
	{
		mScrollAccumulator += deltaTime;

		while(mScrollAccumulator >= SCROLL_TIME)
		{
			mScrollAccumulator -= SCROLL_TIME;
			scroll();
		}

	}else{
		//if we're not scrolling and this object's text goes outside our size, marquee it!
		std::string text = getSelectedName();

		Eigen::Vector2f textSize = mFont->sizeText(text);

		//it's long enough to marquee
		if(textSize.x() - mMarqueeOffset > getSize().x() - 12 - (mAlignment != ALIGN_CENTER ? mHorizontalMargin : 0))
		{
			mMarqueeTime += deltaTime;
			while(mMarqueeTime > MARQUEE_SPEED)
			{
				mMarqueeOffset += MARQUEE_RATE;
				mMarqueeTime -= MARQUEE_SPEED;
			}
		}
	}

	GuiComponent::update(deltaTime);
}

template <typename T>
void TextListComponent<T>::scroll()
{
	mCursor += mScrollDir;

	if(mCursor < 0)
	{
		if(mScrollDir < -1)
			mCursor = 0;
		else
			mCursor += mRowVector.size();
	}
	if(mCursor >= (int)mRowVector.size())
	{
		if(mScrollDir > 1)
			mCursor = (int)mRowVector.size() - 1;
		else
			mCursor -= mRowVector.size();
	}

	onCursorChanged(CURSOR_SCROLLING);

	if(mScrollSound)
		mScrollSound->play();
}

//list management stuff
template <typename T>
void TextListComponent<T>::add(const std::string& name, const T& obj, unsigned int color)
{
	assert(color < COLOR_ID_COUNT);

	ListRow row = {name, obj, color};
	mRowVector.push_back(row);
}

template <typename T>
void TextListComponent<T>::remove(const T& obj)
{
	for(auto it = mRowVector.begin(); it != mRowVector.end(); it++)
	{
		if((*it).object == obj)
		{
			if(mCursor > 0 && it - mRowVector.begin() >= mCursor)
			{
				mCursor--;
				onCursorChanged(CURSOR_STOPPED);
			}

			mRowVector.erase(it);
			return;
		}
	}

	LOG(LogError) << "Tried to remove an object we couldn't find";
}

template <typename T>
void TextListComponent<T>::clear()
{
	mRowVector.clear();
	mCursor = 0;
	mScrollDir = 0;
	mMarqueeOffset = 0;
	mMarqueeTime = -MARQUEE_DELAY;
	onCursorChanged(CURSOR_STOPPED);
}

template <typename T>
void TextListComponent<T>::setCursor(const T& obj)
{
	for(auto it = mRowVector.begin(); it != mRowVector.end(); it++)
	{
		if((*it).object == obj)
		{
			mCursor = it - mRowVector.begin();
			onCursorChanged(CURSOR_STOPPED);
			return;
		}
	}

	LOG(LogError) << "Tried to set cursor to object we couldn't find";
}


template <typename T>
void TextListComponent<T>::setCursor(typename std::vector<ListRow>::const_iterator& it)
{
	assert(it != mRowVector.end());
	mCursor = it - mRowVector.begin();
	onCursorChanged(CURSOR_STOPPED);
}

template <typename T>
void TextListComponent<T>::onCursorChanged(CursorState state)
{
	if(mCursorChangedCallback)
		mCursorChangedCallback(state);
}

template <typename T>
void TextListComponent<T>::applyTheme(const std::shared_ptr<ThemeData>& theme, const std::string& view, const std::string& element, unsigned int properties)
{
	GuiComponent::applyTheme(theme, view, element, properties);

	const ThemeData::ThemeElement* elem = theme->getElement(view, element, "textlist");
	if(!elem)
		return;

	using namespace ThemeFlags;
	if(properties & COLOR)
	{
		if(elem->has("selectorColor"))
			setSelectorColor(elem->get<unsigned int>("selectorColor"));
		if(elem->has("selectedColor"))
			setSelectedColor(elem->get<unsigned int>("selectedColor"));
		if(elem->has("primaryColor"))
			setColor(0, elem->get<unsigned int>("primaryColor"));
		if(elem->has("secondaryColor"))
			setColor(1, elem->get<unsigned int>("secondaryColor"));
	}

	setFont(Font::getFromTheme(elem, properties, mFont));
	
	if(properties & SOUND && elem->has("scrollSound"))
		setSound(Sound::get(elem->get<std::string>("scrollSound")));

	if(properties & ALIGNMENT)
	{
		if(elem->has("alignment"))
		{
			const std::string& str = elem->get<std::string>("alignment");
			if(str == "left")
				setAlignment(ALIGN_LEFT);
			else if(str == "center")
				setAlignment(ALIGN_CENTER);
			else if(str == "right")
				setAlignment(ALIGN_RIGHT);
			else
				LOG(LogError) << "Unknown TextListComponent alignment \"" << str << "\"!";
		}
		if(elem->has("horizontalMargin"))
		{
			mHorizontalMargin = elem->get<float>("horizontalMargin") * (mParent ? mParent->getSize().x() : (float)Renderer::getScreenWidth());
		}
	}
}

#endif