#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include "bmplib.h"

Font::Font(string stfn)
{ const char *fn=stfn.c_str();
  char fn1[100], fn2[100];
  strcpy(fn1, "/usr/local/fonts/");
  strcat(fn1, fn);
  for (int i=0; 1; i+=1)
  { char c=fn1[i];
    if (c==0) break;
    if (c>='A' && c<='Z')
      fn1[i]=c+32; }
  strcpy(fn2, fn1);
  strcat(fn1, ".fom");
  strcat(fn2, ".fon");
  ok=0;
  baseline=0;
  int fom=open(fn1, O_RDONLY);
  int fon=open(fn2, O_RDONLY);
  for (int i=0; i<128; i+=1)
    font[i]=NULL;
  if (fom<0 || fon<0)
  { fprintf(stderr, "Can't find font '%s'\n", fn);
    return; }
  byte bb[20];
  while (1)
  { int n=read(fom, bb, 10);
    if (n!=10) break;
    charinfo * ci= new charinfo;
    font[bb[0]]=ci;
    ci->width=bb[1];
    ci->height=bb[2];
    ci->ascent=bb[3];
    baseline=bb[3];
    ci->blanks=bb[4];
    ci->rows=bb[5];
    ci->bytesperrow=bb[6];
    ci->offset=bb[7] | (bb[8]<<8) | (bb[9]<<16);
    int size=ci->rows*ci->bytesperrow;
    byte * pp = new byte[size];
    if (size>0)
    { lseek(fon, ci->offset, SEEK_SET);
      read(fon, pp, size); }
    ci->pattern=pp; }
  close(fom);
  close(fon);
  ok=1; }

Font::~Font(void)
{ for (int i=0; i<128; i+=1)
  { if (font[i]!=NULL)
    { delete[] font[i]->pattern;
      delete font[i]; } } }

void Font::MeasureString(string st, int & w, int & h)
{ h=0;
  w=0;
  const char * s=st.c_str();
  for (int i=0; 1; i+=1)
  { int c=s[i];
    if (c==0) break;
    if (c<0 || c>127) continue;
    if (font[c]==NULL) continue;
    h=font[c]->height;
    w+=font[c]->width; } }

Picture::Picture(int w, int h, int bgcol=0xFFFFFF)
{ int size=w*h;
  thefont=NULL;
  paper=new unsigned int[size];
  if (paper==NULL)
  { paperw=0;
    paperh=0;
    paper=dummypaper;
    return; }
  for (int i=0; i<size; i+=1)
    paper[i]=bgcol;
  curcol=0;
  thefont=new Font("times-20");
  origfont=1;
  paperw=w;
  paperh=h; }

Picture::~Picture(void)
{ if (paper!=dummypaper)
  { delete[] paper;
    paper=dummypaper;
    paperw=0;
    paperh=0; }
  if (origfont)
    delete thefont; }

void Picture::SetColour(int c)
{ curcol=c; }

void Picture::SetFont(Font *f)
{ origfont=0;
  thefont=f; }

int MakeRGB(int r, int g, int b)
{ return ((b&0xFF)<<16) | ((g&0xFF)<<8) | (r&0xFF); }

int Picture::GetPixel(int x, int y)
{ if (x<0 || y<0 || x>=paperw || y>=paperh)
    return 0;
  return paper[y*paperw+x]; }

void Picture::SetPixel(int x, int y, int c)
{ if (x<0 || y<0 || x>=paperw || y>=paperh)
    return;
  paper[y*paperw+x]=c; }

void Picture::SetPixel(int x, int y)
{ if (x<0 || y<0 || x>=paperw || y>=paperh)
    return;
  paper[y*paperw+x]=curcol; }

void Picture::FillRectangle(int x, int y, int w, int h, int c)
{ if (x<0) { w+=x; x=0; }
  if (y<0) { h+=y; y=0; }
  int maxx=x+w, maxy=y+h;
  if (maxx>paperw) maxx=paperw;
  if (maxy>paperh) maxy=paperh;
  for (int i=y; i<maxy; i+=1)
  { int y0=i*paperw;
    for (int j=x; j<maxx; j+=1)
      paper[y0+j]=c; } }

void Picture::FillRectangle(int x, int y, int w, int h)
{ FillRectangle(x, y, w, h, curcol); }

void Picture::DrawRectangle(int x, int y, int w, int h)
{ if (x<0) { w+=x; x=0; }
  if (y<0) { h+=y; y=0; }
  int maxx=x+w, maxy=y+h;
  if (maxx>paperw) maxx=paperw;
  if (maxy>paperh) maxy=paperh;
  w=maxx-x;
  h=maxy-y;
  if (w<0) w=0;
  if (h<0) h=0;
  int p0=y*paperw;
  for (int j=x; j<maxx; j+=1)
    paper[p0+j]=curcol;
  p0=(y+h-1)*paperw;
  for (int j=x; j<maxx; j+=1)
    paper[p0+j]=curcol;
  p0=y*paperw+x;
  for (int j=0; j<h; j+=1)
  { paper[p0]=curcol;
    p0+=paperw; }
  p0=y*paperw+x+w-1;
  for (int j=0; j<h; j+=1)
  { paper[p0]=curcol;
    p0+=paperw; } }

void Picture::DrawLine(int x0, int y0, int x1, int y1, int w=1)
{ double distx=x1-x0, disty=y1-y0;
  double dist=sqrt(distx*distx+disty*disty);
  double dx=distx/dist, dy=disty/dist;
  double normx=-dy, normy=dx;
  if (dist<0.4) return;
  for (int line=1-w; line<=w-1; line+=2)
  { double shove=0.5*line;
    double x=x0+shove*normx, y=y0+shove*normy;
    for (int i=0; i<=dist; i+=1)
    { SetPixel((int)(x+0.5), (int)(y+0.5));
      x+=dx;
      y+=dy; } } }

void Picture::DrawArrow(int x, int y, int dx, int dy, int size, int fatness=1)
{ if (size==0) return;
  double magd=sqrt(dx*dx+dy*dy);
  if (magd==0) return;
  double dirx=dx/magd, diry=dy/magd;
  double normx=-diry, normy=dirx;
  DrawLine(x+(int)(size*(normx-dirx)+0.5), y+(int)(size*(normy-diry)+0.5), x, y, fatness);
  DrawLine(x+(int)(size*(-normx-dirx)+0.5), y+(int)(size*(-normy-diry)+0.5), x, y, fatness); }

void Picture::LeftOf(int x, int y, int dx, int dy, int dist, int & xx, int & yy)
{ double magd=sqrt(dx*dx+dy*dy);
  if (magd==0.0) { xx=x-dist; yy=y; return; }
  double dirx=dx/magd, diry=dy/magd;
  xx=(int)(x+dist*diry+0.5);
  yy=(int)(y-dist*dirx+0.5); }

int Picture::DrawChar(int x, int y, int c)
{ if (c<0 || c>127) return 0;
  charinfo * ci=thefont->font[c];
  if (ci==NULL) return 0;
  int rr=ci->rows, cc=ci->bytesperrow;
  byte * pp=ci->pattern;
  for (int r=0; r<rr; r+=1)
  { int yp=y+r+ci->blanks;
    for (int c=0; c<cc; c+=1)
    { byte b=pp[r*cc+c];
      int xp=x+(c<<3);
      for (int i=0; i<8; i+=1)
      { if (b&0x80)
          SetPixel(xp+i, yp);
        b<<=1; } } }
  return ci->width; }

int Picture::DrawString(int x, int y, string st)
{ const char *s=st.c_str();
  int len=0;
  for (int i=0; 1; i+=1)
  { char c=s[i];
    if (c==0) break;
    len+=DrawChar(x+len, y, c); }
  return len; }

struct BMPHeader
{ short int rubbish;
  char letterB;
  char letterM;
  int filesize;
  int reserved;
  int dataoffset; };

struct BMPInfoHeader
{ int forty;
  int width;
  int height;
  short int planes;
  short int bitsperpixel;
  int compression;
  int imagesize;
  int xpixelspermetre;
  int ypixelspermetre;
  int numcolours;
  int numimportantcolours; };

int Picture::SaveAsBMP(string fname)
{ FILE *f=fopen(fname.c_str(), "w");
  if (f==NULL) return 0;
  int x=0, y=0, w=paperw, h=paperh;
  BMPHeader h1;
  h1.letterB='B';
  h1.letterM='M';
  int bytesperline=3*w;
  int extraperline=(4-(bytesperline&3))&3;
  bytesperline+=extraperline;
  int filesize=54+bytesperline*h;
  int extrafile=(4-(filesize&3))&3;
  h1.filesize=filesize+extrafile;
  h1.reserved=0;
  h1.dataoffset=54;
  fwrite(&h1.letterB, 14, 1, f);
  BMPInfoHeader h2;
  h2.forty=40;
  h2.width=w;
  h2.height=h;
  h2.planes=1;
  h2.bitsperpixel=24;
  h2.compression=0;
  h2.imagesize=0;
  h2.xpixelspermetre=3936;
  h2.ypixelspermetre=3936;
  h2.numcolours=0;
  h2.numimportantcolours=0;
  fwrite(&h2, 40, 1, f);
  for (int yc=y+h-1; yc>=y; yc-=1)
  { for (int xc=x; xc<x+w; xc+=1)
    { int c=GetPixel(xc, yc);
      int v=(c>>16)|(c&0xFF00)|((c&0xFF)<<16);
      fwrite(&v, 3, 1, f); }
    if (extraperline>0)
    { int n=0;
      fwrite(&n, extraperline, 1, f); } }
  if (extrafile>0)
  { int n=0;
    fwrite(&n, extrafile, 1, f); }
  fclose(f);
  return 1; }