Grid Game

///////////////////////////////////////////////////////////////////////////////
// Grid Game
///////////////////////////////////////////////////////////////////////////////
// Grid game board program that lets users move a cursor around on a board
///////////////////////////////////////////////////////////////////////////////

#include <stdio.h>      // For I/O
#include <stdlib.h>     // For rand
#include <time.h>       // For seeding Rand
#include <string>     // For memset

// Need to include windows so that we can capture key presses properly
#if defined _WIN32 || defined __CYGWIN__
#include <windows.h>
#endif

#define USE_SEPARATE_FILES
#ifdef USE_SEPARATE_FILES
#include "RenderContext.h"
#include "I_Drawable.h"
#include "GameBoard.h"
#ifdef WIN32
#include "CmdPromptHelper.h"
#endif
#else

// RenderContext
#ifndef USE_SEPARATE_FILES
// Class that acts a canvas for things to draw to
class RenderContext {
private:
   int m_width, m_height; // Width and Height of this canvas
   char* m_renderBuffer; // Array to hold "pixels" of canvas
   char m_clearChar; // What to clear the array to

public:
   // Empty Constructor
   RenderContext() : m_width(50), m_height(20), m_clearChar(' ') {
      m_renderBuffer = new char[m_width * m_height];
   }

   // Construct to specify width and height of canvas
   RenderContext(int width, int height) : m_width(width), m_height(height), m_clearChar(' ') {
      m_renderBuffer = new char[m_width * m_height];
   }

   // Destructor
   ~RenderContext() {
      if (m_renderBuffer) {
         delete m_renderBuffer;
      }
   }

   // Get a specific "pixel" on a canvas
   char getContentAt(int x, int y) {
      if (((0 <= x) && (x < m_width)) && ((0 <= y) && (y < m_height))) {
         return m_renderBuffer[(x + (y * m_width))];
      }
   }

   // Fill a specific "pixel" on the canvas
   void setContentAt(int x, int y, char val) {
      if (((0 <= x) && (x < m_width)) && ((0 <= y) && (y < m_height))) {
         m_renderBuffer[(x + (y * m_width))] = val;
      }
   }

   // Change what this canvas is flooded with when cleared
   void setClearChar(char clearChar) {
      m_clearChar = clearChar;
   }

   // Paint the canvas to the shell
   void render() {
      int row, column;
      for (row = 0; row < m_height; row++) {
         for (column = 0; column < m_width; column++) {
            printf("%c", getContentAt(column, row));
         }
         printf("\n");
      }
   }

   // Clear the canvas
   void clear() {
      memset(m_renderBuffer, m_clearChar, m_width * m_height);
   }
};
#endif

// I_Drawable
#ifndef USE_SEPARATE_FILES
// Interface that allows objects to draw to the canvas
class I_Drawable {
public:
   // Virtual function that draws to the canvas
   virtual void draw(RenderContext&) = 0;
};
#endif

// Marker
#ifndef USE_SEPARATE_FILES
// Class representing the cursor that selects objects on a game board
class Marker : public I_Drawable {
private:
   int m_xPos, m_yPos; // Position of cursor
public:
   // Empty constructor
   Marker() : m_xPos(0), m_yPos(0) {
   }
   // Parameterized constructor allowing for setting of initial position
   Marker(int xPos, int yPos) : m_xPos(xPos), m_yPos(yPos) {
   }
   // Draw the cursor to the canvas
   void draw(RenderContext& renderTarget) {

      // Adjust marker by board spacing
      // (This is kind of a hack and should be changed)
      int tmpX, tmpY;
      tmpX = ((m_xPos * 5) + 1);
      tmpY = ((m_yPos * 3) + 1);

      // Set surrounding elements
      renderTarget.setContentAt(tmpX - 0, tmpY - 1, '-');
      renderTarget.setContentAt(tmpX - 1, tmpY - 0, '|');
      renderTarget.setContentAt(tmpX - 0, tmpY + 1, '-');
      renderTarget.setContentAt(tmpX + 1, tmpY - 0, '|');
   }
   // Get x position
   int getXPos() {
      return m_xPos;
   }
   // Get y position
   int getYPos() {
      return m_yPos;
   }
   // Set x position
   void setXPos(int xPos) {
      m_xPos = xPos;
   }
   // Set y position
   void setYPos(int yPos) {
      m_yPos = yPos;
   }
};
#endif

// MoveDirection
#ifndef USE_SEPARATE_FILES
// Enumeration to hold directions a cursor can move
typedef enum {
   MD_UP,
   MD_DOWN,
   MD_LEFT,
   MD_RIGHT
} MoveDirection;
#endif

// GameBoard
#ifndef USE_SEPARATE_FILES
// Class to represent the board of a game being played
class GameBoard : public I_Drawable {
private:
   int m_width, m_height; // Width and height of the board
   int m_verticalSpacing, m_horizontalSpacing; // Spaces between each element on the board
   Marker m_marker; // The cursor that will draw on this board
   int* m_board; // Array of elements on this board

   // Set a value at a spot on this board
   // (There is no actual padding on the board, so do not include vertical/horizontal spacing)
   void setAtPos(int x, int y, int val) {
      if (((0 <= x) && (x < m_width)) && ((0 <= y) && (x < m_height))) {
         m_board[(x + (y * m_width))] = val;
      }
   }

   // Actually create the board
   void generateBoard() {
      int row, column, randomNumber, valToLeft, valToTop;

      // Iterate over all rows and columns
      for (row = 0; row < m_height; row++) {
         for (column = 0; column < m_width; column++) {
            // Get the previous elements
            valToLeft = getAtPos(column - 1, row);
            valToTop = getAtPos(column, row - 1);

            // Generate random numbers until we have one
            // that is not the same as an adjacent element
            do {
               randomNumber = (2 + (rand() % 7));
            } while ((valToLeft == randomNumber) || (valToTop == randomNumber));
            setAtPos(column, row, randomNumber);
         }
      }
   }

public:
   // Empty Constructor
   GameBoard() : m_width(10), m_height(10), m_verticalSpacing(5), m_horizontalSpacing(3), m_marker(Marker()) {
      m_board = new int[m_width * m_height];
      generateBoard();
   }

   // Constructor that takes a width and height of a board
   GameBoard(int width, int height) : m_width(width), m_height(height), m_verticalSpacing(5), m_horizontalSpacing(3), m_marker(Marker()) {
      m_board = new int[m_width * m_height];
      generateBoard();
   }

   // Destructor
   ~GameBoard() {
      if (m_board) {
         delete m_board;
      }
   }

   // Function to get an element on the board
   // I would say overload operator() but it's often overkill
   // and can lead to hard to find bugs
   int getAtPos(int x, int y) {
      if (((0 <= x) && (x < m_width)) && ((0 <= y) && (x < m_height))) {
         return m_board[(x + (y * m_width))];
      }
   }

   // Function to draw to the canvas
   void draw(RenderContext& renderTarget) {
      int row, column;
      char buffer[8];

      // Iterate over every element
      for (row = 0; row < m_height; row++) {
         for (column = 0; column < m_width; column++) {

            // Convert the integer to a char
            sprintf(buffer, "%d", getAtPos(column, row));

            // Set the canvas "pixel" to the char at the
            // desired position including the padding
            renderTarget.setContentAt(
                    ((column * m_verticalSpacing) + 1),
                    ((row * m_horizontalSpacing) + 1),
                    buffer[0]);
         }
      }

      // Draw the marker
      m_marker.draw(renderTarget);
   }

   // Function to move the cursor around depending on input
   // (Does not allow the cursor to move off of the board)
   void handleInput(MoveDirection moveDirection) {
      switch (moveDirection) {
         case MD_UP:
            if (m_marker.getYPos() > 0) {
               m_marker.setYPos(m_marker.getYPos() - 1);
            }
            break;
         case MD_DOWN:
            if (m_marker.getYPos() < m_height - 1) {
               m_marker.setYPos(m_marker.getYPos() + 1);
            }
            break;
         case MD_LEFT:
            if (m_marker.getXPos() > 0) {
               m_marker.setXPos(m_marker.getXPos() - 1);
            }
            break;
         case MD_RIGHT:
            if (m_marker.getXPos() < m_width - 1) {
               m_marker.setXPos(m_marker.getXPos() + 1);
            }
            break;
      }
   }

   // Get the width of the board
   int getWidth() {
      return m_width;
   }

   // Get the height of the board
   int getHeight() {
      return m_height;
   }
};
#endif

// CmdPromptHelper
#ifndef USE_SEPARATE_FILES
// This class is only useful if we are building on windows
#ifdef WIN32

// Class to help with drawing on the windows command prompt
class CmdPromptHelper {
private:
   DWORD inMode; // Attributes of std::in before we change them
   DWORD outMode; // Attributes of std::out before we change them
   HANDLE hstdin; // Handle to std::in
   HANDLE hstdout; // Handle to std::out
public:
   // Empty constructor
   CmdPromptHelper() {
      // Get a handle to input of prompt
      hstdin = GetStdHandle(STD_INPUT_HANDLE);
      if ((hstdin == INVALID_HANDLE_VALUE)
              || !GetConsoleMode(hstdin, &inMode)
              || !SetConsoleMode(hstdin, 0)) {
         return;
      }

      // Get handle for output of prompt
      hstdout = GetStdHandle(STD_OUTPUT_HANDLE);
      if ((hstdout == INVALID_HANDLE_VALUE)
              || !GetConsoleMode(hstdout, &outMode)) {
         return;
      }
   }

   // Revert the console
   void reset() {
      SetConsoleMode(hstdin, inMode);
   }

   // See what key is pressed by the user and return it
   WORD getKeyPress() {
      if (hstdin != INVALID_HANDLE_VALUE) {
         DWORD count;
         INPUT_RECORD inrec;

         // Get Key Press
         ReadConsoleInput(hstdin, &inrec, 1, &count);

         // Return key
         if (inrec.Event.KeyEvent.bKeyDown) {
            return inrec.Event.KeyEvent.wVirtualKeyCode;
         }

         // Flush input
         FlushConsoleInputBuffer(hstdin);
      } else {
         return 0;
      }
   }

   // Flood the console with empty space so that we can
   // simulate single buffering (I have no idea how to double buffer this)
   void clearScreen() {
      if (hstdout != INVALID_HANDLE_VALUE) {
         CONSOLE_SCREEN_BUFFER_INFO csbi;
         DWORD cellCount; // How many cells to paint
         DWORD count; // How many we painted
         COORD homeCoord = {0, 0}; // Where to put the cursor when we're done

         // Get console info
         if (!GetConsoleScreenBufferInfo(hstdout, &csbi)) {
            return;
         }

         // Get cell count
         cellCount = csbi.dwSize.X * csbi.dwSize.Y;

         // Fill the screen with spaces
         FillConsoleOutputCharacter(
                 hstdout,
                 (TCHAR) ' ',
                 cellCount,
                 homeCoord,
                 &count
                 );

         // Set cursor position
         SetConsoleCursorPosition(hstdout, homeCoord);
      }
   }
};
#endif

#endif

#endif
// Entry point of program
int main() {
   // Create a game board
   GameBoard gb(5, 5);

   // Create something to render to
   RenderContext rc(25, 15);
   rc.setClearChar('.');
   rc.clear();

   // If on windows, we can animate
#ifdef WIN32
   // Make a helper
   CmdPromptHelper cph;

   // Variable to hold key presses
   WORD key;

   // Play Game
   do {
      // Draw the board to the render object
      gb.draw(rc);

      // Draw the render object
      rc.render();

      // Get Key Press
      key = cph.getKeyPress();

      // Handle the key press
      switch (key) {
         case VK_UP:
            gb.handleInput(MD_UP);
            break;
         case VK_DOWN:
            gb.handleInput(MD_DOWN);
            break;
         case VK_LEFT:
            gb.handleInput(MD_LEFT);
            break;
         case VK_RIGHT:
            gb.handleInput(MD_RIGHT);
            break;
      }

      // Clear Screen
      rc.clear();
      cph.clearScreen();

   } while (key != VK_ESCAPE);

   // Reset console
   cph.reset();

   // If we aren't on windows, we can't animate and have
   // to write OS specific code to handle key presses
#else

   // Variable to hold key presses
   char key;

   // Play Game
   do {
      // Draw the board to the render object
      gb.draw(rc);

      // Draw the render object
      rc.render();

      // Get Key Press
      key = getchar();

   } while (key != 0);

#endif
}

// EoF