#include "kottui/kottui.h"
#include "tier0/lib.h"
#include "tier0/mem.h"
#include "tier1/utlstring.h"
#include "tier2/ifilesystem.h"
#include "tier2/fileformats/json.h"
#include "trig.h"

struct GlyphData_t
{
	uint32_t m_uCharacter;
	float m_fX;
	float m_fY;
	float m_fWidth;
	float m_fHeight;
};

class CKotRenderFont: public IKotRenderFont
{
public:
	virtual IImage *GetAtlas() override;
	virtual bool IsLetterPresent( uint32_t letter ) override;
	virtual float GetLetterX( uint32_t letter ) override;
	virtual float GetLetterY( uint32_t letter ) override;
	virtual float GetWidth( uint32_t letter ) override;
	virtual float GetHeight( uint32_t letter ) override;

	virtual bool IsMono() override;
	virtual uint32_t GetLetterWidth() override;
	virtual uint32_t GetLetterHeight() override;

	GlyphData_t *m_glyphs;
	uint32_t m_uGlyphCount;
	IImage *m_pAtlas;
};

class CKotUIBuffer: public IKotUIBuffer
{
public:
	virtual void SetPosition( int iY, int iX ) override;

	virtual void Move( int iY, int iX ) override;

	virtual void SetColor( char c ) override;
	virtual void Clear( char c ) override;

	virtual void PutChar( char c ) override;
	virtual void Printf(const char *szFormat, ...) override;

	virtual void Draw( IImage *pImage ) override;

	virtual void SetTextSize( int iY, int iX ) override;
	virtual void SetTextFont( IKotRenderFont *pFont ) override;

	uint32_t *m_buffer;
	ColorAlpha *m_primaryColor;
	ColorAlpha *m_secondaryColor;
	int m_iWidth = 0;
	int m_iHeight = 0;
	IBuffer *m_pDataBuffer;

	IMaterial *m_pMaterial;
	IRenderContext *m_pRenderContext;
	IKotRenderFont *m_pFont;

	uint32_t m_uCursor = 0;
};

class CKotUIManager: public IKotUIManager
{
public:
	virtual void Init() override;
	virtual void Shutdown() override;
	virtual void ConnectInterface( void *pIface, const char *szName ) override;

	virtual IKotRenderFont *LoadFont( const char *szPath ) override;

	virtual IKotUIBuffer *CreateBuffer( int iWidth, int iHeight ) override;
	virtual void DeleteBuffer( IKotUIBuffer *pBuffer ) override;


	IRenderContext *m_pRenderContext;
	ITextureArray *m_pFonts;
};

static IShader *s_pShader;
static CKotUIManager s_kotUIManager;
static IVertexBuffer *s_pGlyphBuffer;

IKotUIManager *KotUIManager()
{
	return &s_kotUIManager;
}
EXPOSE_INTERFACE_FN(KotUIManager, IKotUIManager, KOT_UI_INTEFACE_VERSION);

IImage *CKotRenderFont::GetAtlas()
{
	return m_pAtlas;
}

bool CKotRenderFont::IsLetterPresent( uint32_t letter )
{
	for ( int i = 0; i < m_uGlyphCount; i++ )
	{
		GlyphData_t g =  m_glyphs[i];
		if (g.m_uCharacter == letter)
			return true;
	}
	return false;
}

float CKotRenderFont::GetLetterX( uint32_t letter )
{
	for ( int i = 0; i < m_uGlyphCount; i++ )
	{
		GlyphData_t g =  m_glyphs[i];
		if (g.m_uCharacter == letter)
			return g.m_fX;
	}
	return 0;
}

float CKotRenderFont::GetLetterY( uint32_t letter )
{
	for ( int i = 0; i < m_uGlyphCount; i++ )
	{
		GlyphData_t g =  m_glyphs[i];
		if (g.m_uCharacter == letter)
			return g.m_fY;
	}
	return 0;
}

float CKotRenderFont::GetWidth( uint32_t letter )
{	
	for ( int i = 0; i < m_uGlyphCount; i++ )
	{
		GlyphData_t g =  m_glyphs[i];
		if (g.m_uCharacter == letter)
			return g.m_fWidth;
	}
	return 0;
}

float CKotRenderFont::GetHeight( uint32_t letter )
{
	for ( int i = 0; i < m_uGlyphCount; i++ )
	{
		GlyphData_t g =  m_glyphs[i];
		if (g.m_uCharacter == letter)
			return g.m_fHeight;
	}
	return 0;
}



void CKotUIBuffer::SetPosition( int iY, int iX )
{

}

void CKotUIBuffer::Move( int iY, int iX )
{
	m_uCursor = iY*m_iWidth+iX;
	m_uCursor = m_uCursor % (m_iWidth * m_iHeight);
}

void CKotUIBuffer::SetColor( char c )
{

}

void CKotUIBuffer::Clear( char c )
{

}

void CKotUIBuffer::PutChar( char c )
{
	m_buffer[m_uCursor] = c;
	Move(0, m_uCursor+1);

}

void CKotUIBuffer::Printf(const char *szFormat, ...)
{

	va_list vlArgs;
	va_start(vlArgs, szFormat);
	va_list vlArgs2;
	va_copy(vlArgs2, vlArgs);

	size_t nSize = V_vsnprintf(NULL, 0, szFormat, vlArgs2);
	va_end(vlArgs2);
	char *psz = (char*)V_malloc(nSize+1);
	va_copy(vlArgs2, vlArgs);
	V_vsnprintf(psz, nSize+1, szFormat, vlArgs2);
	for ( size_t u = 0, i = m_uCursor; u < nSize; u++, i = (i + 1 % (m_iWidth * m_iHeight)) )
	{
		m_buffer[i] = psz[u];
	}
	va_end(vlArgs2);
	V_free(psz);
	va_end(vlArgs);
	Move(0, m_uCursor+1);

}

struct TextDrawData_t
{
	float m_vTexcoordOffsetX;
	float m_vTexcoordOffsetY;
	float m_vTexcoordSizeX;
	float m_vTexcoordSizeY;
	float m_fPosX;
	float m_fPosY;
	float m_fSizeX;
	float m_fSizeY;
	float m_fColor[4];
	float m_fColor2[4];
};

struct ScreenData_t
{
	float m_fScreenSizeX;
	float m_fScreenSizeY;
};

void CKotUIBuffer::Draw( IImage *pImage )
{
	uint32_t uGlyphCount = m_iWidth*m_iHeight;
	uint32_t uRealGlyphCount = 0;

	IRenderCommandList *pList = m_pRenderContext->CreateCommandList();
	pList->StartRecording();

	m_pDataBuffer->Lock();
	TextDrawData_t *pData = (TextDrawData_t*)m_pDataBuffer->Map();
	for ( uint32_t i = 0; i < uGlyphCount; i++ )
	{
		uint32_t l = m_buffer[i];
		if ( !m_pFont->IsLetterPresent(l) )
			continue;
		pData[uRealGlyphCount].m_vTexcoordOffsetX = m_pFont->GetLetterX(l);
		pData[uRealGlyphCount].m_vTexcoordOffsetY = m_pFont->GetLetterY(l);
		pData[uRealGlyphCount].m_vTexcoordSizeX = m_pFont->GetWidth(l);
		pData[uRealGlyphCount].m_vTexcoordSizeY = m_pFont->GetHeight(l);
		pData[uRealGlyphCount].m_fSizeX = 16;
		pData[uRealGlyphCount].m_fSizeY = 16;
		pData[uRealGlyphCount].m_fPosX = i%m_iWidth*16;
		pData[uRealGlyphCount].m_fPosY = i/m_iWidth*16;
		uRealGlyphCount++;
	}
	m_pDataBuffer->Unmap();
	m_pDataBuffer->Unlock();
	
	IBuffer *pScreenBuffer = m_pRenderContext->CreateConstantBuffer(sizeof(ScreenData_t));
	pScreenBuffer->Lock();
	ScreenData_t *pScreenData = (ScreenData_t*)pScreenBuffer->Map();
	pScreenData->m_fScreenSizeX = pImage->GetImageWidth();
	pScreenData->m_fScreenSizeY = pImage->GetImageHeight();
	pScreenBuffer->Unmap();
	pScreenBuffer->Unlock();

	m_pMaterial = m_pRenderContext->CreateMaterial(s_pShader);
	m_pMaterial->PSSetShaderResource(0, m_pDataBuffer);
	m_pMaterial->PSSetShaderResource(1, pScreenBuffer);
	m_pMaterial->PSSetTexture(2, m_pFont->GetAtlas());
	m_pMaterial->PSSetSampler(3, m_pRenderContext->GetDefaultSampler());


	pList->SetRenderTarget(0, pImage);
	pList->SetLoadStoreModes(0, LOAD_MODE_LOAD, STORE_MODE_STORE);
	pList->SetRenderResolution(pImage->GetImageWidth(), pImage->GetImageHeight());

	pList->SetMaterial(m_pMaterial);
	pList->SetVertexBuffer(0, s_pGlyphBuffer);
	pList->DrawPrimitives(6, 0, uRealGlyphCount, 0);

	pList->EndRecording();
	m_pRenderContext->SubmitCommandList(pList);

}

void CKotUIBuffer::SetTextSize( int iY, int iX )
{
	

}

void CKotUIBuffer::SetTextFont( IKotRenderFont *pFont )
{
	m_pFont = pFont;

}


void CKotUIManager::Init()
{
	s_pShader = m_pRenderContext->CreateShader("game/core/shaders/kottui.shader_c");
	s_pShader->AddLayout(0, 8);
	s_pShader->AddAttribute(0, 0, VERTEX_FORMAT_XY32_SFLOAT, 0);
	s_pShader->AddOutputImage(0, IMAGE_FORMAT_RGBA8_UNORM);
	s_pShader->Build();
	s_pGlyphBuffer = m_pRenderContext->CreateVertexBuffer(sizeof(float)*12);
	void *pBuffer = s_pGlyphBuffer->Map();
	float vertices[12] = {
		0, 0,
		0, 1,
		1, 0,
		1, 0,
		0, 1,
		1, 1,
	};
	V_memcpy(pBuffer, vertices, sizeof(vertices));
	s_pGlyphBuffer->Unmap();

	m_pFonts = m_pRenderContext->CreateTextureArray();
	

}

void CKotUIManager::Shutdown()
{

}

void CKotUIManager::ConnectInterface( void *pFace, const char *psz )
{
	if (!V_strcmp(psz, RENDER_CONTEXT_INTERFACE_VERSION))
		m_pRenderContext = (IRenderContext*)pFace;
}

IKotRenderFont *CKotUIManager::LoadFont( const char *szPath )
{
	CUtlString szAtlas = CUtlString("%s.png", szPath);
	CUtlString szMeta = CUtlString("%s.fmd", szPath);

	IFileHandle *pMetadataFile = filesystem->Open(szMeta, FILEMODE_READ);
	if (!pMetadataFile)
		return NULL;
	const char *szMetadata = filesystem->ReadString(pMetadataFile);
	filesystem->Close(pMetadataFile);


	IJSONValue *pValue = JSONManager()->ReadString(szMetadata);
	IJSONArray *pGlyphs = pValue->GetObject()->GetValue("glyphs")->GetArray();
	uint32_t uAtlas = m_pFonts->LoadTexture(szAtlas);

	CKotRenderFont *pFont = new CKotRenderFont;
	pFont->m_pAtlas = pFont->m_pAtlas = m_pFonts->GetTexture(uAtlas);
	uint32_t atlasWidth = pValue->GetObject()->GetValue("atlas")->GetObject()->GetValue("width")->GetNumberValue();
	uint32_t atlasHeight = pValue->GetObject()->GetValue("atlas")->GetObject()->GetValue("height")->GetNumberValue();

	pFont->m_uGlyphCount = 0;
	pFont->m_glyphs = (GlyphData_t*)V_malloc(sizeof(GlyphData_t)*pGlyphs->GetCount());
	for ( uint32_t i = 0; i < pGlyphs->GetCount(); i++ )
	{
		GlyphData_t glyph = {};
		IJSONObject *pGlyph = pGlyphs->GetParameter(i)->GetObject();
		if (pGlyph->GetValue("atlasBounds") == NULL)
			continue;
		IJSONObject *pAtlasBounds = pGlyph->GetValue("atlasBounds")->GetObject();
		glyph.m_uCharacter = pGlyph->GetValue("unicode")->GetNumberValue();
		glyph.m_fX = pAtlasBounds->GetValue("left")->GetNumberValue()/atlasWidth;
		glyph.m_fY = 1-(pAtlasBounds->GetValue("bottom")->GetNumberValue()/atlasHeight);
		glyph.m_fWidth = (
				pAtlasBounds->GetValue("right")->GetNumberValue()
				- pAtlasBounds->GetValue("left")->GetNumberValue()
				) / atlasWidth;
		glyph.m_fHeight = (
				pAtlasBounds->GetValue("bottom")->GetNumberValue()
				- pAtlasBounds->GetValue("top")->GetNumberValue()
				) / atlasHeight;
		pFont->m_glyphs[pFont->m_uGlyphCount++] = glyph;
	}
	return pFont;

}

IKotUIBuffer *CKotUIManager::CreateBuffer( int iWidth, int iHeight )
{
	CKotUIBuffer *pBuffer = new CKotUIBuffer;
	pBuffer->m_pRenderContext = m_pRenderContext;
	pBuffer->m_buffer = (uint32_t*)V_malloc(sizeof(uint32_t)*iWidth*iHeight);
	V_memset(pBuffer->m_buffer, 0, sizeof(uint32_t)*iWidth*iHeight);
	pBuffer->m_iWidth = iWidth;
	pBuffer->m_iHeight = iHeight;

	pBuffer->m_pDataBuffer = m_pRenderContext->CreateStorageBuffer(sizeof(TextDrawData_t)*iWidth*iHeight);
	return pBuffer;
}

void CKotUIManager::DeleteBuffer( IKotUIBuffer *pBuffer )
{

}