//===========================================================================
//                                                      CONWAY'S GAME OF LIFE
//                                                            Version 23 FAST
//                                                          19 September 2012
//                                                               Nick Gessler
//                                                        Fast: using TBitmap
//===========================================================================

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;

//===========================================================================
//                                                                   DEFINES
//===========================================================================

#define DEAD 0
#define ALIVE 1
#define RANDOM 2
#define REMEMBEREDWORLD 3

//===========================================================================
//                                                                  VARIABLES
//===========================================================================

bool thisWorld[100][100];
bool nextWorld[100][100];
bool rememberedWorld[100][100];
bool stop = true;
int iterations;
int e, s;    // east & south coordinates of a cell or agent
int nE, nS;  // east & south coordinates of a neighbor of that cell
int livingNeighbors;

Graphics::TBitmap* worldBMP = new Graphics::TBitmap();

//===========================================================================
//                                                                  FUNCTIONS
//===========================================================================

//------------------------ make coordinate valid for a toroidal wrapped world
int w (int coordinate) {
	return (100 + coordinate) % 100;
}

//----------------------------------------------------------- Show This World
void showThisWorld (void) {
	for (int i = 0; i < 100; i++) {
		for (int j = 0; j < 100; j++) {
			if (thisWorld[i][j] == DEAD) {
				worldBMP->Canvas->Brush->Color = clRed;
				worldBMP->Canvas->Pen->Color = clRed;
			}
			if (thisWorld[i][j] == ALIVE) {
				worldBMP->Canvas->Brush->Color = clLime;
				worldBMP->Canvas->Pen->Color = clLime;
			}
			worldBMP->Canvas->
				Rectangle(i * 5, j * 5, i * 5 + 5, j * 5 + 5);
		}
	}
	Form1->PaintBox1->Canvas->Draw(0, 0, worldBMP);
}

//------------------------------------------------------------- Show Changes
void showChanges (void) {
	for (int i = 0; i < 100; i++) {
		for (int j = 0; j < 100; j++) {
			if (thisWorld[i][j] != nextWorld[i][j]) {
				if (nextWorld[i][j] == DEAD) {
					worldBMP->Canvas->Brush->Color = clRed;
					worldBMP->Canvas->Pen->Color = clRed;
				}
				if (nextWorld[i][j] == ALIVE) {
					worldBMP->Canvas->Brush->Color = clLime;
					worldBMP->Canvas->Pen->Color = clLime;
				}
				worldBMP->Canvas->
					Rectangle(i * 5, j * 5, i * 5 + 5, j * 5 + 5);
			}
		}
	}
	Form1->PaintBox1->Canvas->Draw(0, 0, worldBMP);
}

//--------------------------------------------------------------------  Reset
void reset (int choice) {
	iterations = 0;
	for (int i = 0; i < 100; i++) {
		for (int j = 0; j < 100; j++) {
			if (choice == RANDOM) {
				thisWorld[i][j] = random(2);
			}
			if (choice == DEAD) {
				thisWorld[i][j] = DEAD;
			}
			if (choice == REMEMBEREDWORLD) {
            	thisWorld[i][j] = rememberedWorld[i][j];
			}
		}
	}
	showThisWorld();
	Form1->EditIterations->Text = iterations;
}

//---------------------------------------- Copy thisWorld to rememberedWorld
void copyThisWorldToRememberedWorld (void) {
	for (int i = 0; i < 100; i++) {
		for (int j = 0; j < 100; j++) {
			 rememberedWorld[i][j] = thisWorld[i][j];
		}
	}
}

//---------------------------------------------- Copy nextWorld to thisWorld
void copyNextWorldToThisWorld (void) {
	for (int i = 0; i < 100; i++) {
		for (int j = 0; j < 100; j++) {
			thisWorld[i][j] = nextWorld[i][j];
		}
	}
}

//--------------------------------------------------- Count Living Neighbors
int countLivingNeighbors (void) {
	int neighbors = 0;
	for (nE = e - 1; nE <= e + 1; nE++) {
		for (nS = s -1; nS <= s + 1; nS++) {
			if (nE == e && nS == s) {
				continue;
			}
			if (thisWorld[w(nE)][w(nS)] == ALIVE) {
				neighbors++;
			}
		}
	}
	return neighbors;
}

//------------------------------------------------------- Compute Next World
void computeNextWorld (void) {
	for (e = 0; e < 100; e++) {
		for (s = 0; s < 100; s++) {
			livingNeighbors = countLivingNeighbors();
			switch (thisWorld[e][s]) {
				case DEAD:
					if (livingNeighbors == 3) {
						nextWorld[e][s] = ALIVE;
					}
					else {
						nextWorld[e][s] = DEAD;
					}
					break;
				case ALIVE:
					if (livingNeighbors == 3 || livingNeighbors == 2) {
						nextWorld[e][s] = ALIVE;
					}
					else {
						nextWorld[e][s] = DEAD;
					}
					break;
			}
		}
	}
}



//--------------------------------------------------------------------- Step
void step (void) {
	iterations++;
	computeNextWorld();
	showChanges();
	copyNextWorldToThisWorld();
	Form1->EditIterations->Text = iterations;
}

//---------------------------------------------------------------------- Run
void run (void) {
	if (iterations == 0) {
		copyThisWorldToRememberedWorld();
	}
	while(stop == false) {
		step();
		Application->ProcessMessages();
    }
}

//===========================================================================
// 															   EVENT HANDLERS
//===========================================================================

//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
	: TForm(Owner)
{
	randomize();
	reset(RANDOM);
	worldBMP->Height = Form1->PaintBox1->Height;
	worldBMP->Width = Form1->PaintBox1->Width;
}

//---------------------------------------------------------------- Form Paint
void __fastcall TForm1::FormPaint(TObject *Sender)
{
	showThisWorld();
}

//------------------------------------------------------- PaintBox Mouse Down
void __fastcall TForm1::PaintBox1MouseDown(TObject *Sender, TMouseButton
		Button, TShiftState Shift, int X, int Y)
{
	thisWorld[X/5][Y/5] = !thisWorld[X/5][Y/5];
	showThisWorld();
}

//---------------------------------------------------------------- Run Button

void __fastcall TForm1::ButtonRunClick(TObject *Sender)
{
	stop = false;
	run();
}

//--------------------------------------------------------------- Step Button

void __fastcall TForm1::ButtonStepClick(TObject *Sender)
{
	stop = true;   // do we really need this?
	step();
}

//--------------------------------------------------------------- Stop Button

void __fastcall TForm1::ButtonStopClick(TObject *Sender)
{
	stop = true;
}

//------------------------------------------------------- Reset Random Button
void __fastcall TForm1::ButtonRandomClick(TObject *Sender)
{
	reset(RANDOM);
}

//--------------------------------------------------------- Reset Dead Button
void __fastcall TForm1::ButtonDeadClick(TObject *Sender)
{
	reset(DEAD);
}

//----------------------------------------------------- Reset Remember Button
void __fastcall TForm1::ButtonRememberClick(TObject *Sender)
{
	reset(REMEMBEREDWORLD);
}
//---------------------------------------------------------------------------

void __fastcall TForm1::FormClose(TObject *Sender, TCloseAction &Action)
{
	delete worldBMP;
}
//---------------------------------------------------------------------------