#include <iostream.h>

#include "CPstring.h"
#include "observer.h"
#include "walk.h"

// constants define the size of the observing window
// and the size of the rectangle that shows a walker

// MAX_Y = range in Y direction: [-MAX_Y .. MAX_Y]
//         e.g., [-100..100] for MAX_Y = 100
// MAX_X = range in X direction
//
// RECT_HEIGHT = height of rectangle that represents walker
//               graphically
// RECT_WIDTH  =  width of rectangle for walker
//

const int MAX_Y       = 100;     
const int MAX_X       = 100;
const int RECT_HEIGHT = 20;
const int REC_WIDTH   = 20;

// DRAW_WIDTH  =  width used by samba to draw (done in terms of RECT_WIDTH)
// DRAW_HEIGHT =  height used by samba to draw (done in terms of RECT_HEIGHT)

const double  DRAW_WIDTH  = REC_WIDTH;
const double  DRAW_HEIGHT = 3.0 * RECT_HEIGHT / 4.0;


// table of colors (can have more values for more colors)
// also set number of colors = MAX_COLORS

const char * colorTable[] =
{"red","orange", "yellow", "green",
 "cyan","blue", "black", "brown"
};

const int MAX_COLORS = sizeof colorTable / sizeof colorTable[0];

WalkObserver::WalkObserver(ostream & OutputStream, int maxWalkers)
  : myOutputStream(OutputStream)
// postcondition: all fields initizlied
{
    InitializeStream(maxWalkers); // set up animation        
}


void WalkObserver::Update(RandomWalk & walker)
// postcondition: animation/observation is updated for walker     
{
    int id;
    int x;
    int y;
    
    id = walker.GetID();	// the walker's id #
    x  = walker.GetPosition();	// the walker's X-coordinate
    y  = GetYFromID(id);	// the walker's Y-coordinate
    
    MoveRectangle(id, x, y);	// animator command
}

void WalkObserver::InitializeStream(int maxWalkers)
// postcondition: myOutputStream initialized for animation     
{
    int k;
    
    myOutputStream.precision(1);         // show one decimal point for
    myOutputStream.setf(ios::fixed);     // all numbers
    myOutputStream.setf(ios::showpoint);
    
    // initialize coordinates in samba
    
    myOutputStream << "coords " << -MAX_X << " " << -MAX_Y
                   << " "       <<  MAX_X << " " <<  MAX_Y << endl;
    
    // draw a shape (rectangle) for each walker
    
    for (k = 0 ; k < maxWalkers; k++)
    {
	double xStart = 0.0;                   // x-coordinate, bottom left
	double yStart = GetYFromID(k);         // y-coordinate, bottom left
	DrawRectangle(k, xStart, yStart);
    }
    
}

void WalkObserver::DrawRectangle(int id, double x, double y)
// postcondition: rectangle drawn (using Samba)
{
    myOutputStream << "rectangle RECT" << id << " " << x << " " 
	<< y << " " << DRAW_WIDTH << " "  <<  DRAW_HEIGHT  << " " 
	<< GetColorFromID(id) << " solid" << endl; 
}


void WalkObserver::MoveRectangle (int id, double x, double y)
// postcondition: rectangle for a particular walker is moved     
{
    myOutputStream << "move RECT" << id << " " << x << " " << y << endl;
}


string WalkObserver::GetColorFromID (int ColorID)
// postcondition: returns a string that represents a color
//                for drawing in Samba     
{        
    return colorTable[ColorID % MAX_COLORS];    
}

int WalkObserver::GetYFromID(int id)
// postcondition: returns a y-coordinate for walker with id     
{
    return (-MAX_Y + id * RECT_HEIGHT);
}