//////////////////This program is written by Lutz Tautenhahn, Chemnitz 1995.
////////////////////////////////You may use this code for your own purposes.
////////////////////////////////There are no conditions and no restrictions.
#include <graph.h>    
#include <math.h> 
#include <stdio.h> 
#include <stdlib.h> 
#include <string.h>  
#include "ltdiagrm.h" 

LTDiagram::LTDiagram(double theLeftX,
                     double theRightX,
                     double theBottomY,
                     double theTopY,
                     int    theLeft,
                     int    theTop,
                     int    theRight,
                     int    theBottom,
                     void*  theScaleX,
                     void*  theScaleY,
                     void*  theTitle)
{ xmin = theLeftX;
  xmax = theRightX;
  ymin = theBottomY;
  ymax = theTopY;
  left   = theLeft;
  right  = theRight;
  top    = theTop;
  bottom = theBottom; 
  sprintf(xtext,"%s", theScaleX);
  sprintf(ytext,"%s", theScaleY);
  sprintf(title,"%s", theTitle); 
}          
////////////////////////////////////////////////////////////////////////////
void LTDiagram::SetFrame (int theLeft, int theTop, 
                          int theRight, int theBottom)
{ left   = theLeft;
  right  = theRight;
  top    = theTop;
  bottom = theBottom;
}          
////////////////////////////////////////////////////////////////////////////
void LTDiagram::SetBorder(double theLeftX, double theRightX, 
                          double theBottomY, double theTopY)
{ xmin = theLeftX;
  xmax = theRightX;
  ymin = theBottomY;
  ymax = theTopY;
}          
////////////////////////////////////////////////////////////////////////////
void LTDiagram::SetText(void* theScaleX, void* theScaleY, void* theTitle)
{ xtext[0]='\0';
  ytext[0]='\0';                
  title[0]='\0';
  sprintf(xtext,"%s", theScaleX);
  sprintf(ytext,"%s", theScaleY); 
  sprintf(title,"%s", theTitle); 
}
////////////////////////////////////////////////////////////////////////////
int LTDiagram::ScreenX(double theRealX)
{
  return(round((theRealX-xmin)/(xmax-xmin)*(right-left)+left));
}  
////////////////////////////////////////////////////////////////////////////
int LTDiagram::ScreenY(double theRealY)
{           
  return(round((ymax-theRealY)/(ymax-ymin)*(bottom-top)+top));
}  
////////////////////////////////////////////////////////////////////////////
double LTDiagram::RealX(int theScreenX)
{
  return(xmin+(xmax-xmin)*(theScreenX-left)/(right-left));
}  
////////////////////////////////////////////////////////////////////////////
double LTDiagram::RealY(int theScreenY)
{
  return(ymax-(ymax-ymin)*(theScreenY-top)/(bottom-top));
}  
////////////////////////////////////////////////////////////////////////////
int LTDiagram::sign(double rr)
{
  if (rr<0) return(-1); else return(1);
}                                                           
////////////////////////////////////////////////////////////////////////////
int LTDiagram::round( double xx)
{ if (xx < 0.0) xx -= 0.5;
  if (xx > 0.0) xx += 0.5;
  return(int(xx));
}
////////////////////////////////////////////////////////////////////////////
void LTDiagram::Draw(int DrawColor, int TextColor, int ZeroColor, 
                     boolean  isGrid, boolean isScaleText)
{ const int hh=15;
  int x0,y0,i,j,maxpix,itext,ltext,hfont;
  double x,y,r,dx,dy,xl,yl,xr,yr,invdifx,invdify,deltax,deltay;   
  char atext[StringLength];
  struct _fontinfo fi;

  _setgtextvector( 1, 0 );        
  if (_getfontinfo(&fi)<0)
  { _outtext("Error, no font! First use 'setfont'!");
    exit(1);
  }   
  hfont=fi.pixheight/4;   
////////////this seems to be a good fit for small fonts//////////////////////

  invdifx=(right-left)/(xmax-xmin);
  invdify=(bottom-top)/(ymax-ymin);
  _setcolor(DrawColor);
  for (i=left; i<=right; i++)
  { _setpixel(i,top);
    _setpixel(i,bottom);
  }
  for (i=top; i<= bottom; i++)
  { _setpixel(left,i);
    _setpixel(right,i);
  }
///////////////////////////Draw X-Grid//////////////////////////////////////
  dx=(xmax-xmin);
  if (fabs(dx)>0)
  { r=1;
    while (fabs(dx)>=100)
    {
      dx/=10;
      r*=10;
    }
    while (fabs(dx)<10) 
    { dx*=10;
      r/=10;
    };
    if (fabs(dx)>=50) deltax=10*r*sign(dx);
    else 
    { if (fabs(dx)>=20) deltax=5*r*sign(dx);
      else deltax=2*r*sign(dx);
    }     
    x=int(xmin/deltax)*deltax;
    itext=0;
    for (j=12; j>= -1; j--)
    { xr=x+j*deltax;
      xl=left+(-xmin+x+j*deltax)*invdifx;
      x0=round(xl);
      if ((x0>=left)&(x0<=right))
      { itext++;
        _setcolor(TextColor);
        if ((itext!=2)|(!isScaleText)) 
        {  ltext=MinLength(xr);
           sprintf(atext,  "%f", xr);  
           atext[ltext]='\0';
           _moveto(x0- _getgtextextent(atext)/2, bottom+hh);
           _outgtext(atext);
        } 
        else
        {  _moveto(x0- _getgtextextent(xtext)/2, bottom+hh);
           _outgtext(xtext);
        }
        if (isGrid) maxpix=top; else maxpix=bottom-6;                
        _setcolor(DrawColor);
        for (i=maxpix; i<=bottom+6; i++) _setpixel(x0,i);
      }
    }
    x0=round(left-xmin*invdifx);
    if ((x0>=left)&(x0<=right))         
    { _setcolor(ZeroColor);
      for (i=top; i<=bottom; i++) _setpixel(x0,i);
    }
  }
///////////////////////////Draw Y-Grid//////////////////////////////////////
  dy=ymax-ymin;
  if (fabs(dy)>0)
  { r=1;
    while (fabs(dy)>=100)
    { dy/=10;
      r*=10;
    }
    while (fabs(dy)<10)
    { dy*=10;
      r/=10;
    }
    if (fabs(dy)>=50) deltay=10*r*sign(dy);
    else 
    { if (fabs(dy)>=20) deltay=5*r*sign(dy);
      else deltay=2*r*sign(dy);
    }
    y=int(ymax/deltay)*deltay;
    itext=0;
    for (j=-1; j<=12; j++)
    { yr=y-j*deltay;
      yl=top+(ymax-y+j*deltay)*invdify;
      y0=round(yl);
      if ((y0>=top)&(y0<=bottom))
      { itext++;
        _setcolor(TextColor);   
        if ((itext!=2)|(!isScaleText))
        {  ltext=MinLength(yr);
           sprintf(atext,  "%f", yr);  
           atext[ltext]='\0';
           _moveto(left-hh- _getgtextextent(atext),y0-hfont); 
           _outgtext(atext);
        } 
        else 
        { _moveto(left-hh- _getgtextextent(ytext),y0-hfont);  
          _outgtext(ytext);
        }  
        if (isGrid) maxpix=right; else maxpix=left+6; 
        _setcolor(DrawColor);
        for (i=left-6; i<=maxpix; i++) _setpixel(i,y0);
      }
    }
    y0=round(top+ymax*invdify);
    if ((y0>=top)&(y0<=bottom))
    { _setcolor(ZeroColor);
      for (i=left; i<=right; i++) _setpixel(i,y0);
    }
  }
  _setcolor(TextColor);
  _moveto((left+right-hh- _getgtextextent(title))/2, top-hh-2*hfont);
  _outgtext(title);
}                                          
///////////////////////////////////////////////////////////////////////////
int LTDiagram::MinLength(double theValue)
{ boolean isPoint=false;        
  int aOldLength, aNewLength; 
  char aValueChar[20];
  sprintf(aValueChar,  "%f", theValue); 
  aOldLength=strlen(aValueChar);
  aNewLength=aOldLength;
  for(int ii = 0; ii < aOldLength; ii++)   
    if (aValueChar[ii]=='.') isPoint=true;
  if (isPoint==true)       
  { for(int ii = aOldLength-1; ii >= 0; ii--)   
    { if ((isPoint)&((aValueChar[ii]=='0')^(aValueChar[ii]=='.')))
        aNewLength--;
      else isPoint=false;
      if (aValueChar[ii]=='.') isPoint=false;
    }
  }
  return(aNewLength);
}