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

Return to Castle Wolfenstein single player GPL Source Code
Copyright (C) 1999-2010 id Software LLC, a ZeniMax Media company. 

This file is part of the Return to Castle Wolfenstein single player GPL Source Code (RTCW SP Source Code).  

RTCW SP Source Code is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

RTCW SP Source Code is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with RTCW SP Source Code.  If not, see <http://www.gnu.org/licenses/>.

In addition, the RTCW SP Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the RTCW SP Source Code.  If not, please request a copy in writing from id Software at the address below.

If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.

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

// tr_font.c
//
//
// The font system uses FreeType 2.x to render TrueType fonts for use within the game.
// As of this writing ( Nov, 2000 ) Team Arena uses these fonts for all of the ui and
// about 90% of the cgame presentation. A few areas of the CGAME were left uses the old
// fonts since the code is shared with standard Q3A.
//
// If you include this font rendering code in a commercial product you MUST include the
// following somewhere with your product, see www.freetype.org for specifics or changes.
// The Freetype code also uses some hinting techniques that MIGHT infringe on patents
// held by apple so be aware of that also.
//
// As of Q3A 1.25+ and Team Arena, we are shipping the game with the font rendering code
// disabled. This removes any potential patent issues and it keeps us from having to
// distribute an actual TrueTrype font which is 1. expensive to do and 2. seems to require
// an act of god to accomplish.
//
// What we did was pre-render the fonts using FreeType ( which is why we leave the FreeType
// credit in the credits ) and then saved off the glyph data and then hand touched up the
// font bitmaps so they scale a bit better in GL.
//
// There are limitations in the way fonts are saved and reloaded in that it is based on
// point size and not name. So if you pre-render Helvetica in 18 point and Impact in 18 point
// you will end up with a single 18 point data file and image set. Typically you will want to
// choose 3 sizes to best approximate the scaling you will be doing in the ui scripting system
//
// In the UI Scripting code, a scale of 1.0 is equal to a 48 point font. In Team Arena, we
// use three or four scales, most of them exactly equaling the specific rendered size. We
// rendered three sizes in Team Arena, 12, 16, and 20.
//
// To generate new font data you need to go through the following steps.
// 1. delete the fontImage_x_xx.tga files and fontImage_xx.dat files from the fonts path.
// 2. in a ui script, specificy a font, smallFont, and bigFont keyword with font name and
//    point size. the original TrueType fonts must exist in fonts at this point.
// 3. run the game, you should see things normally.
// 4. Exit the game and there will be three dat files and at least three tga files. The
//    tga's are in 256x256 pages so if it takes three images to render a 24 point font you
//    will end up with fontImage_0_24.tga through fontImage_2_24.tga
// 5. You will need to flip the tga's in Photoshop as the tga output code writes them upside
//    down.
// 6. In future runs of the game, the system looks for these images and data files when a s
//    specific point sized font is rendered and loads them for use.
// 7. Because of the original beta nature of the FreeType code you will probably want to hand
//    touch the font bitmaps.
//
// Currently a define in the project turns on or off the FreeType code which is currently
// defined out. To pre-render new fonts you need enable the define ( BUILD_FREETYPE ) and
// uncheck the exclude from build check box in the FreeType2 area of the Renderer project.



#include "tr_local.h"
#include "../qcommon/qcommon.h"

//#define BUILD_FREETYPE
#ifdef BUILD_FREETYPE
#include "../ft2/fterrors.h"
#include "../ft2/ftsystem.h"
#include "../ft2/ftimage.h"
#include "../ft2/freetype.h"
#include "../ft2/ftoutln.h"

#define _FLOOR( x )  ( ( x ) & - 64 )
#define _CEIL( x )   ( ( ( x ) + 63 ) & - 64 )
#define _TRUNC( x )  ( ( x ) >> 6 )

FT_Library ftLibrary = NULL;
#endif

#define MAX_FONTS 6
static int registeredFontCount = 0;
static fontInfo_t registeredFont[MAX_FONTS];

#ifdef BUILD_FREETYPE
void R_GetGlyphInfo( FT_GlyphSlot glyph, int *left, int *right, int *width, int *top, int *bottom, int *height, int *pitch ) {

	*left  = _FLOOR( glyph->metrics.horiBearingX );
	*right = _CEIL( glyph->metrics.horiBearingX + glyph->metrics.width );
	*width = _TRUNC( *right - *left );

	*top    = _CEIL( glyph->metrics.horiBearingY );
	*bottom = _FLOOR( glyph->metrics.horiBearingY - glyph->metrics.height );
	*height = _TRUNC( *top - *bottom );
	*pitch  = ( qtrue ? ( *width + 3 ) & - 4 : ( *width + 7 ) >> 3 );
}


FT_Bitmap *R_RenderGlyph( FT_GlyphSlot glyph, glyphInfo_t* glyphOut ) {

	FT_Bitmap  *bit2;
	int left, right, width, top, bottom, height, pitch, size;

	R_GetGlyphInfo( glyph, &left, &right, &width, &top, &bottom, &height, &pitch );

	if ( glyph->format == ft_glyph_format_outline ) {
		size   = pitch * height;

		bit2 = Z_Malloc( sizeof( FT_Bitmap ) );

		bit2->width      = width;
		bit2->rows       = height;
		bit2->pitch      = pitch;
		bit2->pixel_mode = ft_pixel_mode_grays;
		//bit2->pixel_mode = ft_pixel_mode_mono;
		bit2->buffer     = Z_Malloc( pitch * height );
		bit2->num_grays = 256;

		Com_Memset( bit2->buffer, 0, size );

		FT_Outline_Translate( &glyph->outline, -left, -bottom );

		FT_Outline_Get_Bitmap( ftLibrary, &glyph->outline, bit2 );

		glyphOut->height = height;
		glyphOut->pitch = pitch;
		glyphOut->top = ( glyph->metrics.horiBearingY >> 6 ) + 1;
		glyphOut->bottom = bottom;

		return bit2;
	} else {
		ri.Printf( PRINT_ALL, "Non-outline fonts are not supported\n" );
	}
	return NULL;
}

void WriteTGA( char *filename, byte *data, int width, int height ) {
	byte    *buffer;
	int i, c;

	buffer = Z_Malloc( width * height * 4 + 18 );
	Com_Memset( buffer, 0, 18 );
	buffer[2] = 2;      // uncompressed type
	buffer[12] = width & 255;
	buffer[13] = width >> 8;
	buffer[14] = height & 255;
	buffer[15] = height >> 8;
	buffer[16] = 32;    // pixel size

	// swap rgb to bgr
	c = 18 + width * height * 4;
	for ( i = 18 ; i < c ; i += 4 )
	{
		buffer[i] = data[i - 18 + 2];       // blue
		buffer[i + 1] = data[i - 18 + 1];     // green
		buffer[i + 2] = data[i - 18 + 0];     // red
		buffer[i + 3] = data[i - 18 + 3];     // alpha
	}

	ri.FS_WriteFile( filename, buffer, c );

	//f = fopen (filename, "wb");
	//fwrite (buffer, 1, c, f);
	//fclose (f);

	Z_Free( buffer );
}

static glyphInfo_t *RE_ConstructGlyphInfo( unsigned char *imageOut, int *xOut, int *yOut, int *maxHeight, FT_Face face, const unsigned char c, qboolean calcHeight ) {
	int i;
	static glyphInfo_t glyph;
	unsigned char *src, *dst;
	float scaled_width, scaled_height;
	FT_Bitmap *bitmap = NULL;

	Com_Memset( &glyph, 0, sizeof( glyphInfo_t ) );
	// make sure everything is here
	if ( face != NULL ) {
		FT_Load_Glyph( face, FT_Get_Char_Index( face, c ), FT_LOAD_DEFAULT );
		bitmap = R_RenderGlyph( face->glyph, &glyph );
		if ( bitmap ) {
			glyph.xSkip = ( face->glyph->metrics.horiAdvance >> 6 ) + 1;
		} else {
			return &glyph;
		}

		if ( glyph.height > *maxHeight ) {
			*maxHeight = glyph.height;
		}

		if ( calcHeight ) {
			Z_Free( bitmap->buffer );
			Z_Free( bitmap );
			return &glyph;
		}

/*
	// need to convert to power of 2 sizes so we do not get
	// any scaling from the gl upload
	for (scaled_width = 1 ; scaled_width < glyph.pitch ; scaled_width<<=1)
		;
	for (scaled_height = 1 ; scaled_height < glyph.height ; scaled_height<<=1)
		;
*/

		scaled_width = glyph.pitch;
		scaled_height = glyph.height;

		// we need to make sure we fit
		if ( *xOut + scaled_width + 1 >= 255 ) {
			if ( *yOut + *maxHeight + 1 >= 255 ) {
				*yOut = -1;
				*xOut = -1;
				Z_Free( bitmap->buffer );
				Z_Free( bitmap );
				return &glyph;
			} else {
				*xOut = 0;
				*yOut += *maxHeight + 1;
			}
		} else if ( *yOut + *maxHeight + 1 >= 255 ) {
			*yOut = -1;
			*xOut = -1;
			Z_Free( bitmap->buffer );
			Z_Free( bitmap );
			return &glyph;
		}


		src = bitmap->buffer;
		dst = imageOut + ( *yOut * 256 ) + *xOut;

		if ( bitmap->pixel_mode == ft_pixel_mode_mono ) {
			for ( i = 0; i < glyph.height; i++ ) {
				int j;
				unsigned char *_src = src;
				unsigned char *_dst = dst;
				unsigned char mask = 0x80;
				unsigned char val = *_src;
				for ( j = 0; j < glyph.pitch; j++ ) {
					if ( mask == 0x80 ) {
						val = *_src++;
					}
					if ( val & mask ) {
						*_dst = 0xff;
					}
					mask >>= 1;

					if ( mask == 0 ) {
						mask = 0x80;
					}
					_dst++;
				}

				src += glyph.pitch;
				dst += 256;

			}
		} else {
			for ( i = 0; i < glyph.height; i++ ) {
				memcpy( dst, src, glyph.pitch );
				src += glyph.pitch;
				dst += 256;
			}
		}

		// we now have an 8 bit per pixel grey scale bitmap
		// that is width wide and pf->ftSize->metrics.y_ppem tall

		glyph.imageHeight = scaled_height;
		glyph.imageWidth = scaled_width;
		glyph.s = (float)*xOut / 256;
		glyph.t = (float)*yOut / 256;
		glyph.s2 = glyph.s + (float)scaled_width / 256;
		glyph.t2 = glyph.t + (float)scaled_height / 256;

		*xOut += scaled_width + 1;
	}

	Z_Free( bitmap->buffer );
	Z_Free( bitmap );

	return &glyph;
}
#endif

static int fdOffset;
static byte *fdFile;

int readInt() {
	int i = fdFile[fdOffset] + ( fdFile[fdOffset + 1] << 8 ) + ( fdFile[fdOffset + 2] << 16 ) + ( fdFile[fdOffset + 3] << 24 );
	fdOffset += 4;
	return i;
}

typedef union {
	byte fred[4];
	float ffred;
} poor;

float readFloat() {
	poor me;
#ifdef idppc
	me.fred[0] = fdFile[fdOffset + 3];
	me.fred[1] = fdFile[fdOffset + 2];
	me.fred[2] = fdFile[fdOffset + 1];
	me.fred[3] = fdFile[fdOffset + 0];
#else
	me.fred[0] = fdFile[fdOffset + 0];
	me.fred[1] = fdFile[fdOffset + 1];
	me.fred[2] = fdFile[fdOffset + 2];
	me.fred[3] = fdFile[fdOffset + 3];
#endif
	fdOffset += 4;
	return me.ffred;
}

void RE_RegisterFont( const char *fontName, int pointSize, fontInfo_t *font ) {
#ifdef BUILD_FREETYPE
	FT_Face face;
	int j, k, xOut, yOut, lastStart, imageNumber;
	int scaledSize, newSize, maxHeight, left, satLevels;
	unsigned char *out, *imageBuff;
	glyphInfo_t *glyph;
	image_t *image;
	qhandle_t h;
	float max;
#endif
	void *faceData;
	int i, len;
	char name[1024];
	float dpi = 72;                                         //
	float glyphScale =  72.0f / dpi;        // change the scale to be relative to 1 based on 72 dpi ( so dpi of 144 means a scale of .5 )

	if ( pointSize <= 0 ) {
		pointSize = 12;
	}
	// we also need to adjust the scale based on point size relative to 48 points as the ui scaling is based on a 48 point font
	glyphScale *= 48.0f / pointSize;

	// make sure the render thread is stopped
	R_SyncRenderThread();

	if ( registeredFontCount >= MAX_FONTS ) {
		ri.Printf( PRINT_ALL, "RE_RegisterFont: Too many fonts registered already.\n" );
		return;
	}

	Com_sprintf( name, sizeof( name ), "fonts/fontImage_%i.dat",pointSize );
	for ( i = 0; i < registeredFontCount; i++ ) {
		if ( Q_stricmp( name, registeredFont[i].name ) == 0 ) {
			memcpy( font, &registeredFont[i], sizeof( fontInfo_t ) );
			return;
		}
	}

	len = ri.FS_ReadFile( name, NULL );
	if ( len == sizeof( fontInfo_t ) ) {
		ri.FS_ReadFile( name, &faceData );
		fdOffset = 0;
		fdFile = faceData;
		for ( i = 0; i < GLYPHS_PER_FONT; i++ ) {
			font->glyphs[i].height      = readInt();
			font->glyphs[i].top         = readInt();
			font->glyphs[i].bottom      = readInt();
			font->glyphs[i].pitch       = readInt();
			font->glyphs[i].xSkip       = readInt();
			font->glyphs[i].imageWidth  = readInt();
			font->glyphs[i].imageHeight = readInt();
			font->glyphs[i].s           = readFloat();
			font->glyphs[i].t           = readFloat();
			font->glyphs[i].s2          = readFloat();
			font->glyphs[i].t2          = readFloat();
			font->glyphs[i].glyph       = readInt();
			memcpy( font->glyphs[i].shaderName, &fdFile[fdOffset], 32 );
			fdOffset += 32;
		}
		font->glyphScale = readFloat();
		memcpy( font->name, &fdFile[fdOffset], MAX_QPATH );

//		memcpy(font, faceData, sizeof(fontInfo_t));
		Q_strncpyz( font->name, name, sizeof( font->name ) );
		for ( i = GLYPH_START; i < GLYPH_END; i++ ) {
			font->glyphs[i].glyph = RE_RegisterShaderNoMip( font->glyphs[i].shaderName );
		}
		memcpy( &registeredFont[registeredFontCount++], font, sizeof( fontInfo_t ) );
		return;
	}

#ifndef BUILD_FREETYPE
	ri.Printf( PRINT_ALL, "RE_RegisterFont: FreeType code not available\n" );
#else
	if ( ftLibrary == NULL ) {
		ri.Printf( PRINT_ALL, "RE_RegisterFont: FreeType not initialized.\n" );
		return;
	}

	len = ri.FS_ReadFile( fontName, &faceData );
	if ( len <= 0 ) {
		ri.Printf( PRINT_ALL, "RE_RegisterFont: Unable to read font file\n" );
		return;
	}

	// allocate on the stack first in case we fail
	if ( FT_New_Memory_Face( ftLibrary, faceData, len, 0, &face ) ) {
		ri.Printf( PRINT_ALL, "RE_RegisterFont: FreeType2, unable to allocate new face.\n" );
		return;
	}


	if ( FT_Set_Char_Size( face, pointSize << 6, pointSize << 6, dpi, dpi ) ) {
		ri.Printf( PRINT_ALL, "RE_RegisterFont: FreeType2, Unable to set face char size.\n" );
		return;
	}

	//*font = &registeredFonts[registeredFontCount++];

	// make a 256x256 image buffer, once it is full, register it, clean it and keep going
	// until all glyphs are rendered

	out = Z_Malloc( 1024 * 1024 );
	if ( out == NULL ) {
		ri.Printf( PRINT_ALL, "RE_RegisterFont: Z_Malloc failure during output image creation.\n" );
		return;
	}
	Com_Memset( out, 0, 1024 * 1024 );

	maxHeight = 0;

	for ( i = GLYPH_START; i < GLYPH_END; i++ ) {
		glyph = RE_ConstructGlyphInfo( out, &xOut, &yOut, &maxHeight, face, (unsigned char)i, qtrue );
	}

	xOut = 0;
	yOut = 0;
	i = GLYPH_START;
	lastStart = i;
	imageNumber = 0;

	while ( i <= GLYPH_END ) {

		glyph = RE_ConstructGlyphInfo( out, &xOut, &yOut, &maxHeight, face, (unsigned char)i, qfalse );

		if ( xOut == -1 || yOut == -1 || i == GLYPH_END ) {
			// ran out of room
			// we need to create an image from the bitmap, set all the handles in the glyphs to this point
			//

			scaledSize = 256 * 256;
			newSize = scaledSize * 4;
			imageBuff = Z_Malloc( newSize );
			left = 0;
			max = 0;
			satLevels = 255;
			for ( k = 0; k < ( scaledSize ) ; k++ ) {
				if ( max < out[k] ) {
					max = out[k];
				}
			}

			if ( max > 0 ) {
				max = 255 / max;
			}

			for ( k = 0; k < ( scaledSize ) ; k++ ) {
				imageBuff[left++] = 255;
				imageBuff[left++] = 255;
				imageBuff[left++] = 255;

				imageBuff[left++] = ( (float)out[k] * max );
			}

			Com_sprintf( name, sizeof( name ), "fonts/fontImage_%i_%i.tga", imageNumber++, pointSize );
			if ( r_saveFontData->integer ) {
				WriteTGA( name, imageBuff, 256, 256 );
			}

			//Com_sprintf (name, sizeof(name), "fonts/fontImage_%i_%i", imageNumber++, pointSize);
			image = R_CreateImage( name, imageBuff, 256, 256, qfalse, qfalse, GL_CLAMP );
			h = RE_RegisterShaderFromImage( name, LIGHTMAP_2D, image, qfalse );
			for ( j = lastStart; j < i; j++ ) {
				font->glyphs[j].glyph = h;
				Q_strncpyz( font->glyphs[j].shaderName, name, sizeof( font->glyphs[j].shaderName ) );
			}
			lastStart = i;
			Com_Memset( out, 0, 1024 * 1024 );
			xOut = 0;
			yOut = 0;
			Z_Free( imageBuff );
			i++;
		} else {
			memcpy( &font->glyphs[i], glyph, sizeof( glyphInfo_t ) );
			i++;
		}
	}

	registeredFont[registeredFontCount].glyphScale = glyphScale;
	font->glyphScale = glyphScale;
	memcpy( &registeredFont[registeredFontCount++], font, sizeof( fontInfo_t ) );

	if ( r_saveFontData->integer ) {
		ri.FS_WriteFile( va( "fonts/fontImage_%i.dat", pointSize ), font, sizeof( fontInfo_t ) );
	}

	Z_Free( out );

	ri.FS_FreeFile( faceData );
#endif
}



void R_InitFreeType() {
#ifdef BUILD_FREETYPE
	if ( FT_Init_FreeType( &ftLibrary ) ) {
		ri.Printf( PRINT_ALL, "R_InitFreeType: Unable to initialize FreeType.\n" );
	}
#endif
	registeredFontCount = 0;
}


void R_DoneFreeType() {
#ifdef BUILD_FREETYPE
	if ( ftLibrary ) {
		FT_Done_FreeType( ftLibrary );
		ftLibrary = NULL;
	}
#endif
	registeredFontCount = 0;
}

