#include <stdarg.h>
#include "glbase.h"
#include "glfont.h"
#include "Input.h"

Uint8 prescale2[4] = { 0, 85, 170, 255 }, prescale3[8] = { 0, 36, 72, 109, 145, 182, 218, 255 };

#define DEBUG 1
#define STRBUFSIZ 512

/*

font file format
================

off|siz|description
---+---+-------------------------------
 0 | 2 | Number of entries = nbentries
 2 | 1 | Flags
 3 | 1 | maxX (maximum width)
 4 | 1 | maxY (maximum height)
 5 | 1 | base (bottom line from top)
 6 | 1 | inter (size of the interline)
 7 | X | char entries
7+X| Y | char map

X = (maxX * maxY + 1) * nbentries
Y = nbentries * 4


Flags:
=====

0000000R

R = RGBA (=1) or Alpha (=0)

RGBA in 1232 format:
ABBGGGRR


Each entries:
============

off|siz|description
---+---+-------------------------------
 0 | 1 | True size of the entry
 1 | Z | Datas

Z = maxX * maxY
Datas are stored in order X first, then Y.

Char map:
========

nbentries entries, each entry = 4 bytes = 2 uint16

off|siz|description
---+---+-------------------------------
 0 | 2 | Unicode (?)
 2 | 2 | Corresponding char entry

I'm not sure about my word 'Unicode'. I write this only to say it's an attempt
to make the fonts "internationals". If the "unicode" is < 255, then it should
match only one byte in the string. Otherwise, it should match two bytes.


Variables comments
==================

nbcU = number of chars on X by texture
nbcV = number of chars on Y by texture
nbcT = number of char by texture
nbT  = number of textures

*/

mogltk::font::font(Handle * ffont) : textcolor(255, 255, 255, 255) {
    int i;
    
    ffont->read(&nbentries, 2);
    ffont->read(&flags, 1);
    ffont->read(&maxX, 1);
    ffont->read(&maxY, 1);
    ffont->read(&base, 1);
    ffont->read(&inter, 1);

    nbcU = 256 / maxX;
    nbcV = 256 / maxY;
    
    nbcT = nbcU * nbcV;
    
    nbT = nbentries / nbcT;
    
    if (nbentries % nbcT) {
	nbT++;
    }
    
#ifdef DEBUG
    printm(M_INFO, "Creating font texture: %i entries, flags = 0x%02x, maxX = %i, maxY = %i\n", nbentries, flags, maxX, maxY);
    printm(M_INFO, "Which makes %i texture(s), with %i char by texture, %i on X, and %i on Y\n", nbT, nbcT, nbcU, nbcV);
#endif
    
    fonttex = (texture **) malloc(nbT * sizeof(texture *));
    
    for (i = 0; i < nbT; i++) {
	fonttex[i] = new texture(256, 256, true);
    }
    
    sizes = (Uint8 *) malloc(nbentries * sizeof(Uint8));

    Uint8 * curtex = (Uint8 *) fonttex[0]->GetSurface()->pixels;
    Uint32 curU = 0, curV = 0, curT = 0;
    for (int i = 0; i < nbentries; i++) {
	ffont->read(&sizes[i], 1);
	for (int v = 0; v < maxY; v++) {
	    for (int u = 0; u < maxX; u++) {
		Uint8 f;
		ffont->read(&f, 1);
		if (flags & 1) {
		    Uint8 r, g, b, a;
		    r = f & 3;
		    g = (f >> 2) & 7;
		    b = (f >> 5) & 3;
		    a = (f >> 7) & 1;
		    curtex[(curU + u + (curV + v) * 256) * 4 + 0] = prescale2[r];
		    curtex[(curU + u + (curV + v) * 256) * 4 + 1] = prescale3[g];
		    curtex[(curU + u + (curV + v) * 256) * 4 + 2] = prescale2[b];
		    curtex[(curU + u + (curV + v) * 256) * 4 + 3] = a ? 255 : 0;
		} else {
		    curtex[(curU + u + (curV + v) * 256) * 4 + 0] = 255;
		    curtex[(curU + u + (curV + v) * 256) * 4 + 1] = 255;
		    curtex[(curU + u + (curV + v) * 256) * 4 + 2] = 255;
		    curtex[(curU + u + (curV + v) * 256) * 4 + 3] = f;
		}
	    }
	}
	if (((curU += maxX) + maxX) >= 256) {
	    curU = 0;
	    if (((curV += maxY) + maxY) >= 256) {
		curV = 0;
		if ((curT + 1) != nbT)
		    curtex = (Uint8 *) fonttex[++curT]->GetSurface()->pixels;
	    }
	}
    }

    corresp = (Uint16 *) malloc(nbentries * 2 * sizeof(Uint16));
    
    ffont->read(corresp, 2 * sizeof(Uint16) * nbentries);
}

mogltk::font::~font() {
    int i;
    for (i = 0; i < nbT; i++) {
	delete fonttex[i];
    }
    
    free((void *) fonttex);
    free(sizes);
}

void mogltk::font::drawentry(Uint16 entry, int x, int y, Color c) {
    bool was2D;
    int trueentry, cx, cy, px, py;
    
    was2D = mogltk::glbase::is2D();
    
    if (!was2D) {
	mogltk::glbase::Enter2DMode();
    }
    
    if (shadow) {
	int os = shadow;
	shadow = 0;
	
	drawentry(entry, x + os, y + os, BLACK);
	
	shadow = os;
    }
    
    y -= base;
    
    Bind(entry / nbcT);
    c.Bind();
    trueentry = entry % nbcT;
    cx = trueentry % nbcU;
    cy = trueentry / nbcU;
    px = cx * maxX;
    py = cy * maxY;
    
    glBegin(GL_TRIANGLE_STRIP);
    glTexCoord2i(px           , py           ); glVertex2i(x           , y           );
    glTexCoord2i(px + maxX - 1, py           ); glVertex2i(x + maxX - 1, y           );
    glTexCoord2i(px           , py + maxY - 1); glVertex2i(x           , y + maxY - 1);
    glTexCoord2i(px + maxX - 1, py + maxY - 1); glVertex2i(x + maxX - 1, y + maxY - 1);
    glEnd();
    
    if (!was2D) {
	mogltk::glbase::Leave2DMode();
    }
}

void mogltk::font::Bind(int index) {
    fonttex[index]->Bind();
}

void mogltk::font::putcursor(int x, int y) {
    cx = ox = x;
    cy = y;
}

void mogltk::font::putentry(Uint16 entry, Color c) {
    drawentry(entry, cx, cy, c);
    cx += sizes[entry];
}

void mogltk::font::putchar(char ch, Color c) {
    Uint16 * p;
    int i;

    for (i = 0, p = corresp; i < nbentries; i++, p++) {
	if (*(p++) == ch) {
	    putentry(*p, c);
	    return;
	}
    }
}

void mogltk::font::newline(void) {
    cx = ox;
    cy += inter;
}

int mogltk::font::printf(const String & m, ...) {
    static char buffer[STRBUFSIZ + 1];
    va_list ap;
    char * p;
    int r;
    
    va_start(ap, m);    
    r = vsnprintf(buffer, STRBUFSIZ, m.to_charp(), ap);
    va_end(ap);
    
    for (p = buffer; *p; p++) {
	if (*p == '\n') {
	    newline();
	} else {
	    putchar(*p, textcolor);
	}
    }
    
    return r;
}

void mogltk::font::setcolor(Color c) {
    textcolor = c;
}

void mogltk::font::setshadow(int s) {
    shadow = s;
}