//
//  BitmapHandler.cpp
//  vcmieditor
//
//  Created by nordsoft on 29.08.2022.
//

#include "BitmapHandler.h"

#include "StdInc.h"

#include "../lib/filesystem/Filesystem.h"
#include "BitmapHandler.h"

#include <QBitmap>
#include <QImage>
#include <QPixmap>

namespace BitmapHandler
{
	QImage loadH3PCX(ui8 * data, size_t size);
	
	QImage loadBitmapFromDir(std::string path, std::string fname, bool setKey=true);
}

bool isPCX(const ui8 *header)//check whether file can be PCX according to header
{
	ui32 fSize  = read_le_u32(header + 0);
	ui32 width  = read_le_u32(header + 4);
	ui32 height = read_le_u32(header + 8);
	return fSize == width*height || fSize == width*height*3;
}

enum Epcxformat
{
	PCX8B,
	PCX24B
};

QImage BitmapHandler::loadH3PCX(ui8 * pcx, size_t size)
{
	//SDL_Surface * ret;
	
	Epcxformat format;
	int it=0;
	
	ui32 fSize = read_le_u32(pcx + it); it+=4;
	ui32 width = read_le_u32(pcx + it); it+=4;
	ui32 height = read_le_u32(pcx + it); it+=4;
	
	if (fSize==width*height*3)
		format=PCX24B;
	else if (fSize==width*height)
		format=PCX8B;
	else
		return QImage();
	
	QSize qsize(width, height);
	
	if (format==PCX8B)
	{
		it = 0xC;
		//auto bitmap = QBitmap::fromData(qsize, pcx + it);
		QImage image(pcx + it, width, height, QImage::Format_Indexed8);
		
		//palette - last 256*3 bytes
		QVector<QRgb> colorTable;
		it = (int)size-256*3;
		for (int i=0;i<256;i++)
		{
			char bytes[3];
			bytes[0] = pcx[it++];
			bytes[1] = pcx[it++];
			bytes[2] = pcx[it++];
			colorTable.append(qRgb(bytes[0], bytes[1], bytes[2]));
		}
		image.setColorTable(colorTable);
		return image;
	}
	else
	{
		QImage image(pcx + it, width, height, QImage::Format_RGB32);
		return image;
	}
}

QImage BitmapHandler::loadBitmapFromDir(std::string path, std::string fname, bool setKey)
{
	if(!fname.size())
	{
		logGlobal->warn("Call to loadBitmap with void fname!");
		return QImage();
	}
	if (!CResourceHandler::get()->existsResource(ResourceID(path + fname, EResType::IMAGE)))
	{
		return QImage();
	}
	
	auto fullpath = CResourceHandler::get()->getResourceName(ResourceID(path + fname, EResType::IMAGE));
	auto readFile = CResourceHandler::get()->load(ResourceID(path + fname, EResType::IMAGE))->readAll();
	
	if (isPCX(readFile.first.get()))
	{//H3-style PCX
		auto image = loadH3PCX(readFile.first.get(), readFile.second);
		if(!image.isNull())
		{
			if(image.bitPlaneCount() == 1 && setKey)
			{
				QVector<QRgb> colorTable = image.colorTable();
				colorTable[0] = qRgba(255, 255, 255, 0);
				image.setColorTable(colorTable);
			}
		}
		else
		{
			logGlobal->error("Failed to open %s as H3 PCX!", fname);
		}
		return image;
	}
	else
	{ //loading via SDL_Image
		QImage image(QString::fromStdString(fullpath->native()));
		if(!image.isNull())
		{
			if(image.bitPlaneCount() == 1)
			{
				//set correct value for alpha\unused channel
				QVector<QRgb> colorTable = image.colorTable();
				for(auto & c : colorTable)
					c = qRgb(qRed(c), qGreen(c), qBlue(c));
				image.setColorTable(colorTable);
			}
		}
		else
		{
			logGlobal->error("Failed to open %s via QImage", fname);
			return image;
		}
	}
	return QImage();
	// When modifying anything here please check two use cases:
	// 1) Vampire mansion in Necropolis (not 1st color is transparent)
	// 2) Battle background when fighting on grass/dirt, topmost sky part (NO transparent color)
	// 3) New objects that may use 24-bit images for icons (e.g. witchking arts)
	/*if (ret->format->palette)
	{
		CSDL_Ext::setDefaultColorKeyPresize(ret);
	}
	else if (ret->format->Amask)
	{
		SDL_SetSurfaceBlendMode(ret, SDL_BLENDMODE_BLEND);
	}
	else // always set
	{
		CSDL_Ext::setDefaultColorKey(ret);
	}
	return ret;*/
}

QImage BitmapHandler::loadBitmap(std::string fname, bool setKey)
{
	QImage image = loadBitmapFromDir("DATA/", fname, setKey);
	if(image.isNull())
	{
		image = loadBitmapFromDir("SPRITES/", fname, setKey);
		if(image.isNull())
		{
			logGlobal->error("Error: Failed to find file %s", fname);
		}
	}
	return image;
}